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Coasts & Oceans
A timely opportunity to protect North Atlantic Right Whales in Canada
March 3, 2017Brillant et al. 2017. A timely opportunity to protect North Atlantic Right Whales in Canada. - Quantitative risk analysis of entanglement.
Aquaculture Manual
Aquaculture is the farming of aquatic wildlife like fish, crustaceans, molluscs and aquatic plants. As opposed to commercial fishing, in which fishermen harvest wild fish, aquaculture grows freshwater and saltwater species in controlled conditions. There are various kinds of aquaculture, but the two types of aquaculture this report will highlight in particular are: ■■Closed-containment finfish aquaculture (CCFA)■■Open-pen finfish aquaculture (OPFA)
Assessing the Fate of Returning Upper Yukon River Chinook Salmon - 2017
January 1, 2017To assess the behavior of Chinook Salmon (Oncorhynchus tshawytscha) migrating past the Whitehorse Hydro Plant (WHP), 68 fish were gastrically implanted with acoustic transmitters in 2017. Twenty acoustic receivers were deployed between Lake Laberge and the spawning grounds in the Michie Creek – M’Clintock River system. Forty-eight fish were captured in the Whitehorse Rapids Fishladder viewing chamber, acoustically tagged, and released there.
Assessing the Fate of Returning Upper Yukon River Chinook Salmon - 2018
January 1, 2018A 50-receiver acoustic telemetry array was deployed throughout the Upper Yukon River and supporting tributaries to identify spawning locations of Chinook Salmon (Oncorhynchus tshawytscha) upstream of Lake Laberge, YT.
Assessing the lethality of ship strikes on whales using simple biophysical models
January 1, 2020Studies of ship strikes on whales often focus on large vessels (>20 m), with attention to their speeds and the resulting risk of lethality. Smaller coastal vessels also co-occur with whales, resulting in collisions that merit study. To cast light on injuries caused by vessels of all sizes, we used knowledge of right whale anatomy and Newtonian mechanics to construct simple models that predict the mechanical stresses experienced by whales during collisions. By comparing our predictions with published models and with data from ship strikes on various whale species, we developed a model for lethal injury as a function of several vessel and whale properties, finding that collisions that create stresses in excess of 0.241 MPa were likely to cause lethal injuries to large whales. Furthermore, this model has revealed that (1) vessels of all sizes can yield stresses higher than this critical level, and (2) large vessels produce stresses much larger than this even when travelling at reduced speeds (i.e., 10 knots). The model is fast enough to power an interactive GUI-based tool (in R) and flexible enough to simulate strikes by vessels of different masses and speeds upon whales of different species, sizes, and physical conditions.
Effects of time-area closures on the distribution of snow crab fishing effort with respect to entanglement threat to North Atlantic right whales
October 1, 2021Time-area closures are increasingly used to mitigate cetacean entanglement by temporarily excluding fishing effort from areas where high densities of cetaceans and fishing overlap. The effort displaced by these closures can be redistributed to the areas that remain open, changing the distribution and density of fishing effort outside the closures. These patterns were evaluated for the southern Gulf of St. Lawrence snow crab fishery by comparing recent years (–) with when time-area closures were implemented to protect North Atlantic right whales. A predictive model framework was created to test how well we could predict the response of fishers to closures. Approximately % of the total fishing effort was displaced by the closures, increasing effort density outside the closures by %. Displaced fishing effort shifted farther from the closures than predicted, into areas which, prior to , had low effort density, producing a higher threat of entanglement in these new areas. Fishing effort in remained as high as , despite a lower quota and reduced trap limit. Consequently, the resulting effects of time-area closures on fishing patterns outside of the closures cannot be discounted if entanglement threat to whales is to be successfully mitigated.
Establishing best practices for implanting Passive Integrated Transponder (PIT) tags in American Eel (Anguilla rostrata)
March 1, 2020Workshop Report Ontario Species at Risk Stewardship Program Project #18-19-CWF
Mass human-caused mortality spurs federal action to protect endangered North Atlantic right whales in Canada
October 31, 2012Davies & Brillant 2019. Mass human-caused mortality spurs federal action to protect endangered North Atlantic right whales in Canada. - Review of the new management measures put in place by Government of Canada to protect NARWs. Discusses the need for proactive governance, not reactive measures.
Monitoring North Atlantic right whale entanglement rates: a 30 yr retrospective. Analysis of entanglement rates.
February 18, 2019Knowlton et al. 2012. Monitoring North Atlantic right whale entanglement rates: a 30 yr retrospective. Analysis of entanglement rates. - This paper is the source of entanglement rate statistics. 82.5% of photo identified whales have been entangled at least once in their lifetime, while 59% have been entangled more than once.
Pathways of fish invasions in the Mid-Atlantic region of the United States
March 18, 2016Non-native fish introductions are a major threat to biodiversity and fisheries, and occur through numerous pathways that vary regionally in importance. A key strategy for managing invasions is to focus prevention efforts on pathways posing the greatest risk of future introductions. We identified high-risk pathways for fish establishment in the Mid-Atlantic region of the United States based on estimates of relative probability of establishment among pathways and records of previous introductions, which were considered in the context of emerging socioeconomic trends. We used estimates of propagule pressure, species’ environmental tolerance, and size of species pool to assess the risk of establishment by pathway.
Survey of Chinook Salmon (Oncorhynchus tshawytscha) carcasses in Whitehorse, Yukon - 2017
January 1, 2017Carcass surveys are a useful tool for fisheries management, especially for anadromous fish such as Pacific salmon (Oncorhynchus spp.). They are widely used to inform managers on topics such as escapement, run characteristics, and pre-spawn mortality (DeWeber et al. 2017; Rawding et al. 2014; Murdoch et al. 2010). However, outside of spawning grounds and natal streams, carcass surveys have been used sparsely.
Survey of Chinook Salmon (Oncorhynchus tshawytscha) carcasses in Whitehorse, Yukon - 2018
January 1, 2018Carcass surveys can provide valuable information on escapement, population characteristics, and run timing in anadromous fish stocks. During the 2018 Chinook Salmon (Oncorhynchus tshawytscha) run in the upper Yukon River, carcass surveys were completed daily to provide preliminary information on egg deposition rates and spawning escapement of Chinook Salmon downstream of the Whitehorse Hydro Plant (WHP) and refine carcass survey methods.
The recovery of North Atlantic right whales has been constrained by human-caused mortality
November 11, 2018Cockeron et al. 2018. The recovery of North Atlantic right whales has been constrained by human-caused mortality. - Comparison of population growth with Southern right whales, and the impacts of anthropogenic mortality.
Connecting With Nature
How Neonicotinoid Pesticides May Be Harming Bats
August 26, 2019There are over 1,300 bat species worldwide, 19 of which call Canada home. Our bats are incredibly important, not only to the environment but to the economy too. When the sun goes down, bats get to work eating the annoying pests in our backyards. They’re also extremely beneficial to the agricultural industry. In fact, bats save the agricultural industry in North America $3.7 billion every year.
Restoring habitat for Monarch in eastern Ontario
May 7, 2019Increasingly, private landowners are interested in restoring areas of their property to provide improved habitat for Monarch and other pollinators. While there is abundant information on small-scale gardening with native plants, there is far less information available for restoration plantings at a larger scale. Here is a brief introduction for landowners in eastern Ontario interested in restoring an area of an acre or in a cost-effective way. More detailed information is in progress, so keep in touch for updates. Another great resource from the Xerces Society is Establishing Pollinator Meadows from Seed.
Telemetry-Determined Habitat Use Informs Multi-Species Habitat Management in an Urban Harbour
September 26, 2016Widespread human development has led to impairment of freshwater coastal wetlands and embayments, which provide critical and unique habitat for many freshwater fish species. This is particularly evident in the Laurentian Great Lakes, where such habitats have been severely altered over the last century as a result of industrial activities, urbanization, dredging and infilling. In Toronto Harbour, extensive restoration efforts have been directed towards improving the amount and quality of aquatic habitat, especially for fishes.
Education & Leadership
Endangered Species & Biodiversity
A contemporary estimate for the abundance of juvenile American Eel Anguilla rostrata attempting to migrate past a barrier in the Ottawa River
July 17, 2022American Eel (Anguilla rostrata) travels from the Sargasso Sea to fresh waters of eastern North America and back in a lifetime, and once provided one of the most abundant eel fisheries in the world. Many American Eel populations are now at risk worldwide. Dams act as barriers to the upstream migration of juvenile American Eels, which can be partially mitigated by installing eel ladders. To inform mitigation decisions and provide baseline data, the number of eels approaching barriers should be estimated; however, estimation is difficult for this now rare and cryptic species, especially in large rivers. In St. Lawrence and Ottawa River system, American Eels are among the largest and most fecund of the species, and local populations in the Ottawa River are almost entirely composed of large, female eels. American Eel in this area has declined to less than 1% of historic abundance, yet no local population estimates are available to inform recovery strategies and management actions. We, therefore, evaluated data from an unpublished study to estimate the abundance of American Eel attempting to migrate upstream past a barrier. American Eels (n = 339) were captured at the Carillon Generating Station over 36 days (July 12, 2010–August 17, 2010). Results were fit to the POPAN Jolly-Seber model in program MARK. Future studies could be improved by sampling throughout the migration season and deploying multiple traps spanning downstream features. While confidence intervals in the best-fitting model were wide, the estimate nonetheless provides a baseline to inform future work and management.
A timely opportunity to protect North Atlantic Right Whales in Canada
March 3, 2017Brillant et al. 2017. A timely opportunity to protect North Atlantic Right Whales in Canada. - Quantitative risk analysis of entanglement.
Angler interactions with American eel (Anguilla rostrata): Exploring perspectives and behaviors toward an imperiled fish
November 5, 2020As aquatic biodiversity continues to decline, recreational anglers are interacting more frequently with imperiled species. As a result, management strategies must be developed to balance fisheries management and conservation objectives. Understanding the human dimensions of these encounters is important for both fisheries management and conservation objectives, because decisions made by anglers have a direct impact on the fish. This work explores angler perspectives and behaviors toward American Eel (Anguilla rostrata), a species listed as Endangered in the Canadian province of Ontario and globally (IUCN Red Listed as Endangered), and not typically targeted by recreational anglers in Ontario. Interviews with 48 anglers on the Ottawa River revealed that almost half had captured an eel at some point, but few had intentionally killed eels (in each case prior to the eel’s Endangered status listing in Ontario). However, a large proportion of respondents were, or would be, uncomfortable handling eels if captured, and almost half of respondents declared a limited or lack of knowledge about the species. These findings suggest that discomfort around eels and limited knowledge about their value (both ecological and economical) do not cause direct harm to eels but may impede full public support for conservation of the species.
Apparent winterkill of Painted Turtle
January 1, 2021Around the margin of an artificial pond in Ottawa, Ontario, we found 25 Painted Turtles (Chrysemys picta) that appeared to have died over the course of two winters (17 during the first winter and eight during the second). We examined meteorological data to try to determine the cause of the mortality. Summer and fall rains were only slightly below normal in both years, suggesting water levels should have been close to normal. The winter air temperature was warmer than normal and winter snowfall was slightly above normal in both years. Unseasonable weather does not appear to be responsible for the winter mortality and the pond’s maximum depth of 1.7 m should prevent freezing to the bottom. It is possible that the artificial nature of the pond creates suboptimal overwintering habitat, rendering the site an ecological trap; however, there is no direct evidence to support this theory. It is also possible that winter mortality of turtles is widespread at temperate wetlands, but that dead turtles were more detectable at this site because of the bare shoreline around the pond. Winter mass mortality events, if common, may represent an additional threat to turtle populations, which are declining from various anthropogenic threats.
Aquaculture Manual
Aquaculture is the farming of aquatic wildlife like fish, crustaceans, molluscs and aquatic plants. As opposed to commercial fishing, in which fishermen harvest wild fish, aquaculture grows freshwater and saltwater species in controlled conditions. There are various kinds of aquaculture, but the two types of aquaculture this report will highlight in particular are: ■■Closed-containment finfish aquaculture (CCFA)■■Open-pen finfish aquaculture (OPFA)
Assessing a proponent-driven process for endangered species threat mitigation: Ontario’s Endangered Species Act, American Eel, and hydropower
February 10, 2022American Eel (Anguilla rostrata) were used as a case study to assess whether Ontario’s Endangered Species Act proponent-driven regulatory approach resulted in successful imperilled species management outcomes. American Eel observation databases and proponent-prepared mitigation plans and monitoring data were used to assess whether: (i) facilities within the distribution range were registered, (ii) effects monitoring protocols were adequate to evaluate adverse effects of facilities, (iii) proponents implemented mitigation actions that followed best management practices (BMPs), and (iv) effectiveness monitoring designs were adequate to evaluate effectiveness of mitigation actions. Less than half of the facilities (8 of 17) within the extant species range were registered. Few eels were observed at each facility, precluding proponents from effectively evaluating the facilities’ effects. Mitigation actions following BMPs were only implemented for eel out-migration at three facilities. Half of the registered facilities implemented effectiveness monitoring, but experimental designs did not follow best practices and standards. To improve this proponent-driven approach, regulators could reduce ambiguity in regulation language and provide clearer, quantitative requirements for facility registration, effects monitoring, mitigation actions, and effectiveness monitoring. Proponents could improve monitoring efforts to establish species occurrence and generate baseline data to measure facility effects and mitigation action effectiveness.
Assessing terrestrial movements of Eastern Musk Turtle (Sternotherus odoratus) using iNaturalist Canada
July 1, 2024Eastern Musk Turtle (Sternotherus odoratus) is known to be a highly aquatic species, yet it is occasionally found away from waterbodies. If such movements are common, then road mortality may pose a substantial risk to the species. We examined iNaturalist Canada observations of Eastern Musk Turtle on roads and found 15 in which individuals were >25 m from water. The median distance to the nearest permanent waterbody was 100 m (range 30–330 m). All observations that were ≥100 m from the nearest waterbody occurred from mid-July onward, suggesting that the movements were not related to nesting activity. At least under some circumstances, Eastern Musk Turtle can move >100 m away from waterbodies increasing the risk of road mortality.
Assessing the fate of returning upper Yukon River Chinook salmon (2017-2020)
May 18, 2021Chinook salmon (Oncorhynchus tshawytscha) from the Upper Yukon River have faced severe declines relative to their estimated abundances several decades ago. To further our understanding of Chinook salmon spawning locations in this area, and potential factors limiting the recovery of this population, we completed a 4-year telemetry study from 2017-2020. Efforts were focused on understanding the effectiveness of the Whitehorse Rapids Fishladder at allowing salmon to pass upstream of the Whitehorse Hydro Plant. To answer these questions, a telemetry array was deployed throughout the upper Yukon River and supporting tributaries upstream of Lake Laberge, YT. Salmon of both wild and hatchery origin were gastrically implanted with acoustic/radio transmitters at the fish ladder viewing chamber or downstream following gill net capture to evaluate passage success and subsequent spawning locations. Over the course of four years, a total of 171 tagged salmon passed upstream of the Whitehorse Hydro Plant with 78% terminating in the Michie Creek - M’Clintock River system, with the remainder terminating in Wolf Creek, the Yukon River mainstem, the Takhini River, and the Southern Lakes. Salmon tagged below the hydro plant that approached the fish ladder often did not pass through the structure. Salmon ceased upstream migration at multiple points within the ladder, including the viewing chamber where a gate must be manually lifted by staff to allow salmon passage. Findings from this work may be used to inform future spawning ground surveys, restoration actions, and design and operational changes at the Whitehorse Rapids Fishladder.
Assessing the Fate of Returning Upper Yukon River Chinook Salmon - 2017
January 1, 2017To assess the behavior of Chinook Salmon (Oncorhynchus tshawytscha) migrating past the Whitehorse Hydro Plant (WHP), 68 fish were gastrically implanted with acoustic transmitters in 2017. Twenty acoustic receivers were deployed between Lake Laberge and the spawning grounds in the Michie Creek – M’Clintock River system. Forty-eight fish were captured in the Whitehorse Rapids Fishladder viewing chamber, acoustically tagged, and released there.
Assessing the Fate of Returning Upper Yukon River Chinook Salmon - 2018
January 1, 2018A 50-receiver acoustic telemetry array was deployed throughout the Upper Yukon River and supporting tributaries to identify spawning locations of Chinook Salmon (Oncorhynchus tshawytscha) upstream of Lake Laberge, YT.
Assessing the Fate of Returning upper Yukon River Chinook Salmon - 2019
June 1, 2021- This is the first of the three years of this study that fish have neither terminated in the Upper M’Clintock River above the confluence with Michie Creek nor in Wolf Creek. - Two fish terminated in the Southern Lakes (Marsh Lake and Tagish Lake south of Tutshi) with a potential third fish having terminated in Marsh Lake - Unique terminal locations were identified in Michie Creek using manual tracking
Assessing the Fate of Returning upper Yukon River Chinook Salmon - 2020
June 1, 2021- Fall back (or over shoot) after passing the Whitehorse Hydro Plant was substantial (31%) compared to previous years of study - Many fish migrating into Michie Creek ventured to the uppermost reaches of the creek and even Michie Lake - Recovery of a tagged female carcass revealed successful egg deposition in the Yukon River mainstem above the WHP
Backgrounder: CWF Fish Passage Projects 2019-2020
November 18, 2020The Canadian Wildlife Federation (CWF) is pleased to release details of 2019-2020 projects restoring fish passage in B.C. thanks to funding from the provincial and federal governments and the support of multiple partners.
Bats & Neonics Report
The purpose of the review by Pierre Mineau and CWF’s Carolyn Callaghan is to examine the various lines of evidence that new systemic insecticides may be putting Canadian bats at risk. Specifically, this review investigates the risk and magnitude of neonicotinoid exposure for bats foraging in agricultural landscapes, and assess the resulting direct risk to bats by constructing a formal risk assessment following an exhaustive review of what is known currently about the mammalian toxicology of neonics. The indirect effects of neonicotinoid insecticides in bats will also be explored by reviewing the case for insect declines and the probable involvement of neonicotinoid insecticides in these declines.
Bright spots for inland fish and fisheries to guide future hydropower development
January 24, 2022Hydropower production is one of the greatest threats to fluvial ecosystems and freshwater biodiversity. Now that we have entered the Anthropocene, there is an opportunity to reflect on what might constitute a ‘sustainable’ Anthropocene in the context of hydropower and riverine fish populations. Considering elements of existing practices that promote favorable social-ecological outcomes (i.e., ‘bright spots’) is timely given that there are plans to expand hydropower capacity in previously undammed rivers, intensify dam development in some of the world's largest river systems, and re-license existing facilities. We approach this from a pragmatic perspective: for the foreseeable future, hydropower will likely remain an important source of renewable electricity. To offer support for moving toward a more ‘sustainable’ Anthropocene, we provide syntheses of best practices during the siting, design, construction, operation, and compensation phases of hydropower development to minimize impacts on inland fish. For each phase, we offer positive examples (or what might be considered ‘bright spots’) pertaining to some of the approaches described within our syntheses, acknowledging that these projects may not be viewed as without ecological and (or) societal detriment by all stakeholders. Our findings underscore the importance of protecting critical habitat and free-flowing river reaches through careful site selection and basinscale planning, infrastructure designs that minimize reservoir effects and facilitate safe passage of fish, construction of hydropower plants using best practices that minimize long-term damage, operating guidelines that mimic natural flow conditions, and compensation that is lasting, effective, inclusive, and locally relevant. Learning from these ‘bright spots’ may require engagement of diverse stakeholders, professionals, and governments at scales that extend well beyond a given site, river, or even basin. Indeed
Bulkley River Watershed (Laxyip | Wedzin Kwah): Connectivity Remediation Plan: 2021 - 2031
August 1, 2021This plan represents the culmination of a collaborative planning process undertaken in the Bulkley River watershed over many months of work with a multi-partner planning team of individuals and groups passionate about the conservation and restoration of freshwater ecosystems and the species they support. Plan development was funded by the BC Salmon Restoration and Innovation Fund and the RBC Bluewater Project.
Developing a national level evidence-based toolbox for addressing freshwater biodiversity threats
March 30, 2022Freshwater biodiversity is in a state of crisis. The recent development of a global emergency recovery plan to “bend the curve” for freshwater biodiversity lacks the necessary details for implementation in a regional context. Using Canada as an example, we describe a toolbox intended to equip decision-makers and practitioners with evidence-based tools for addressing threats to freshwater biodiversity. The toolbox includes two rubric-based scoring tools to inform users about the level of the reliability (e.g., transparent methods, critical appraisal) and relevancy to Canadian freshwater systems (e.g., habitat, species) of an evidence synthesis. Those scoring tools were applied to 259 evidence syntheses, also included in the toolbox, across fifty freshwater management actions. Habitat Creation, Invasive Species Removal, and Revegetation were found to have reliable evidence syntheses but there remain several actions for which the syntheses are not robust and where the evidence base is unreliable. We suggest the need for more rigorously conducted empirical tests of freshwater management actions, further evidence synthesis, and clearer conveyance of implications for decision-makers and practitioners.
Do turtle warning signs reduce roadkill?
October 1, 2019Roadkill is a serious threat for many species of freshwater turtles. One of the most common road mitigation tools is wildlife warning signs to alert drivers. These warning signs have commonly been used for large mammals, although there is little evidence that they are effective in reducing roadkill. We tested the effectiveness of turtle warning signs at four known roadkill hotspots along a provincial highway in eastern Ontario and compared the results with four control sites on a nearby major road in a before-after-control-impact (BACI) study. We found 30 dead turtles in the four hotspots in 2017 before the signs were installed and 27 in 2018 after the signs were installed. The number of turtles killed on the road after the signs were installed did not change significantly (χ21 = 1.1, P > 0.2). Although turtle warning signs may alert some drivers, they should not be considered a replacement for more effective road mitigation tools, such as wildlife fencing and crossing structures.
Does catch-and-release angling pose a threat to American eel? A hooking mortality experiment
January 16, 2020Incidental capture of protected fishes usually calls for immediate release, however, post-release survival has not been investigated for many protected species. The American eel Anguilla rostrata is an example of an imperiled species that is incidentally captured by recreational anglers, but for which the impacts of catch and release are unknown. In this study, we examined the short-term (7 d) mortality and injury of American eels (n = 207) following simulated catch-and-release scenarios (involving manually embedded hooks) in a controlled experiment. Specifically, we compared the effects of cutting the line versus removing the hook, as well as shallow versus deep hooking, in holding tanks. No mortalities occurred in any of the groups during a 7 d monitoring period, and most eels exhibited little to mild injury. A high degree of hook shedding occurred in groups where the hook was shallowly embedded. Hooking depth was significantly related to hook-shedding rate, with 93.7% of hooks shed in the shallow-hook−line-cut group compared to 71.8% of hooks shed in the deep-hook−line-cut group. Our results suggest that recreationally captured American eels may be relatively resilient to catch and release, but validation of these results in a field setting is recommended.
Effects of rail infrastructure on Pacific salmon and steelhead habitat connectivity in British Columbia
February 1, 2024The effects of rail infrastructure on the connectivity of habitat for Chinook (Oncorhynchus tshawytscha), Coho (O. kisutch), Sockeye (O. nerka), Chum (O. keta), and Pink salmon (O. gorbuscha) and anadromous Rainbow Trout (O. mykiss) in British Columbia were estimated. Habitats upstream of major hydro dams lacking fishways were not considered. Natural habitat accessibility was modelled for each species based on swimming ability and stream gradient, excluding habitats upstream of steep gradients, large waterfalls, or areas with subsurface flows. Within these naturally accessible habitats, areas that may support spawning and rearing were identified using intrinsic potential models. Anthropogenic structures that may be barriers to fish movement were then overlaid to identify habitat that may be blocked. Similar estimates of lateral habitat fragmentation were made by modelling lateral habitat along the floodplain, overlaying rail-stream crossings and lines, and identifying areas that may be disconnected by them
Establishing best practices for implanting Passive Integrated Transponder (PIT) tags in American Eel (Anguilla rostrata)
March 1, 2020Workshop Report Ontario Species at Risk Stewardship Program Project #18-19-CWF
Fate of translocated American eel (Anguilla rostrata) in the lower Ottawa River and passage behavior at a multichannel barrier
January 1, 2021American eel (Anguilla rostrata) is considered endangered under the IUCN's red list. Hydropower facilities are considered a significant threat to American eel, impacting both the outmigration of adults and upstream migration of juveniles. To overcome upstream passage issues, juvenile eels may be trapped and transported around barriers as a mitigation strategy, though few studies have evaluated the efficacy of this approach. To understand the fate of transported eels, we monitored posttranslocation movements in a 110-km reach of the Ottawa River bounded by two hydropower facilities: Carillon Hydroelectric Generating Station (lower barrier) and Chaudière Falls Hydroelectric Facility (upper barrier). Additionally, we assessed the approach behavior of eels that reached the upper barrier, a multichannel facility, to assess potential fishway locations. To assess these objectives, 40 juvenile eels (440–640 mm) were implanted with acoustic transmitters and were transported and released either just upstream (6 km) of the lower barrier or just downstream of the upper barrier (2 km), approximately, 60 and 166 km from the capture site, respectively. Over the three-month study period, 78% of tagged eels remained upstream of the lower barrier. Of the nine eels that returned downstream of the lower barrier, seven were from the downstream release site; however, the proportion of eels that returned downstream of the lower barrier did not differ significantly between release sites. One eel passed the upper barrier despite no existing fish-passage structures. At the upper barrier, most eels visited just one of the five channels, suggesting that more than one passage structure may be necessary to allow eels entering different channels to pass upstream of the barrier. Findings from this work will help inform passage efforts for American eel, particularly in the Ottawa River where eel populations have declined severely from their historic abundance.
High egg retention in Chinook Salmon Oncorhynchus tshawytscha carcasses sampled downstream of a migratory barrier
January 1, 2021Barriers in rivers have the potential to severely decrease functional connectivity between habitats. Failure to pass barriers and reach natal spawning habitat may compromise individual reproductive success, particularly for semelparous, philopatric species that rely on free-flowing rivers to reach natal habitat during their once-in-alifetime spawning migrations. To investigate the consequences of in-river barriers on fish spawning success, we quantified egg retention and spawning effort (caudal fin wear) in female Chinook Salmon Oncorhynchus tshawytscha carcasses collected downstream of the Whitehorse Hydro Plant on the upper Yukon River and at a nearby free-flowing tributary (Teslin River) from 2018 to 2020 (2900 km migrations). Previous studies have demonstrated that a large proportion of fish attempting to reach spawning locations upstream of the hydro plant fail to pass the associated fishway. We estimated nearly all female salmon failing to pass the hydro plant attempted spawning in non-natal habitat downstream, but that these females retained 34% of their total fecundity compared to 6% in females from the free-flowing river. Females downstream of the hydro plant also had lower wear on their caudal fin, a characteristic that was correlated with increased egg deposition. Egg retention did not vary across years with different run sizes, and we propose that egg retention downstream of the hydro plant was not driven by density-dependent mechanisms. Findings from this work indicate that female Chinook Salmon can still deposit eggs following failed fish passage and failure to reach natal spawning sites, though egg retention rates are considerably higher and uncertainties remain about reproductive success. We encourage researchers to incorporate carcass surveys into fish passage evaluations for semelparous species to fully account for consequences of failed passage.
Horizon scan of conservation issues for inland waters in Canada
March 22, 2019Horizon scanning is a systematic approach increasingly used to explore emerging trends, issues, opportunities, and threats in conservation. We present the results from one such exercise aimed at identifying emerging issues that could have important scientific, social, technological, and managerial implications for the conservation of inland waters in Canada in the proximate future. We recognized six opportunities and nine challenges, for which we provide research implications and policy options, such that scientists, policy makers, and the Canadian society as a whole can prepare for a potential growth in each of the topic areas we identified. The issues spanned a broad range of topics, from recognizing the opportunities and challenges of community-enabled science and the need to consider the legal rights of nature, to the likely increase of pharmaceuticals in wastewater due to an aging population. These issues represent a first baseline that could help decision makers identify and prioritize efforts while simultaneously stimulate new research avenues. We hope our horizon scan will pave the way for similar exercises related to the conservation of biodiversity in Canada.
Horsefly River Watershed Secwepemcúl’ecw, Connectivity Remediation Plan: 2021 - 2040
August 1, 2021This plan represents the culmination of a collaborative planning process undertaken in the Horsefly River watershed over many months of work with a multi-partner planning team of individuals and groups passionate about the conservation and restoration of freshwater ecosystems and the species they support. Plan development was funded by the BC Salmon Restoration and Innovation Fund, Canada Nature Fund for Aquatic Species at Risk, and the RBC Bluewater Project. We were fortunate to benefit from the feedback, guidance, and wisdom of many groups and individuals who volunteered their time throughout this process — this publication would not have been possible without the engagement of our partners and the planning team (
Insights into Chinook salmon (Oncorhynchus tshawytscha) movement ecology in the terminal reaches of the upper Yukon River during the spawning migration
August 24, 2022Chinook salmon (Oncorhynchus tshawytscha (Walbaum, 1792)) from the upper Yukon River are highly unique, with some populations migrating nearly 3000 km to spawning habitat near the northern range limit for the species. We conducted a 4-year study to understand the behaviour of Chinook salmon in the terminal reaches of their migration by tagging salmon with acoustic and radio transmitters in Whitehorse, Yukon, Canada, ∼2800 km from the ocean. Various migration characteristics were quantified for Chinook salmon, including en route mortality, diel behaviour, migration rates, and homing patterns, and associations with salmon origin (wild vs. hatchery), sex, size, and migration timing were explored. Salmon had high survival to spawning grounds (>98%) and migrated throughout all hours of the day, with higher proportions of nighttime movements in a smaller spawning tributary than in the Yukon River mainstem. Migration rates were faster for larger salmon as well as latearriving salmon, which was likely necessary to ensure they had sufficient time and suitable conditions on spawning grounds to reproduce. Non-direct homing movements (e.g., tributary exploration) were more common in male salmon and considerably increased migration distance through the study area. Findings from this study may help to inform the complex international and inter-nation management of these increasingly threatened Chinook salmon populations
Joint Letter for the American Eel Timeline, February 26, 2017
February 24, 2017We are writing regarding your response, dated September 13th, 2016, to the letter sent by the Canadian Wildlife Federation, Ottawa Riverkeeper, Ontario Rivers Alliance and Ontario Nature on August 22nd, 2016 expressing concern over the delay by the Province of Ontario in producing a government response statement (GRS) following publication of the Recovery Strategy for American Eel. In your response, you indicated that a draft would be ready for public consultation this winter.
Joint Letter for the American Eel, August 22, 2016
August 22, 2016We are writing to express concern over the unlawful delay by the Province of Ontario in producing a government response statement following publication of the recovery strategy for American Eel. This recovery strategy was published on November 22nd, 2013, nearly five months past the legal deadline under Ontario’s Endangered Species Act (ESA). As of today, the response statement is now two years overdue. The Canadian Wildlife Federation wrote you regarding this issue on July 12th, 2016, but to date has received only an acknowledgement of the letter. The lack of communication from the Ontario Government regarding the cause of this delay and when the response statement will be issued is of great concern.
Landscape factors influencing roost site selection by monarch butterflies Danaus plexippus during fall migration in Ontario, Canada
April 1, 2023Worldwide, insect populations are declining, and the eastern migratory group of the monarch butterfly Danaus plexippus in North America has not escaped this fate. The conservation of this iconic species is an international priority but requires knowledge of how monarchs interact with the landscape during different stages of the annual cycle. To better understand habitat needs of monarchs departing their core breeding range in southern Ontario, Canada, we examined how various landscape features influenced roost site selection during fall migration—an instrumental resource link between the breeding and wintering grounds. Using dedicated fall migration surveys along the Great Lakes coastlines and a citizen science dataset collected across all of Ontario, we evaluated the relationship between roost site occupancy and 18 landscape variables using a boosted regression tree (BRT) modelling approach. Results suggest that a closer distance to the Great Lakes, increased goldenrod Solidago spp. cover, moderate forest cover, rural road cover, and urban land cover are all important to roosting site selection. Our research provides important insights into the habitat characteristics of stopover sites, which will help guide future investigations and conservation actions to preserve monarch butterflies and their migratory phenomenon.
Lower Nicola River Watershed, Connectivity Remediation Plan: 2021 - 2031
August 1, 2021This plan represents the culmination of a collaborative planning process undertaken in the Lower Nicola River watershed over many months of work with a multi-partner planning team of individuals and groups passionate about the conservation and restoration of freshwater ecosystems and the species they support. Plan development was funded by the BC Salmon Restoration and Innovation Fund, Canada Nature Fund for Aquatic Species at Risk, and the RBC Bluewater Project. We were fortunate to benefit from the feedback, guidance, and wisdom of many groups and individuals who volunteered their time throughout this process — this publication would not have been possible without the engagement of our partners and the planning team
Mass human-caused mortality spurs federal action to protect endangered North Atlantic right whales in Canada
October 31, 2012Davies & Brillant 2019. Mass human-caused mortality spurs federal action to protect endangered North Atlantic right whales in Canada. - Review of the new management measures put in place by Government of Canada to protect NARWs. Discusses the need for proactive governance, not reactive measures.
Monitoring North Atlantic right whale entanglement rates: a 30 yr retrospective. Analysis of entanglement rates.
February 18, 2019Knowlton et al. 2012. Monitoring North Atlantic right whale entanglement rates: a 30 yr retrospective. Analysis of entanglement rates. - This paper is the source of entanglement rate statistics. 82.5% of photo identified whales have been entangled at least once in their lifetime, while 59% have been entangled more than once.
Record longevity of a Spotted Turtle
Turtles are known for their longevity, but the maximum life span for many species remains unknown. Spotted Turtle (Clemmys guttata) can live for more than 30 years in the wild, but typical or maximum longevity has not been confirmed. As part of a long-term mark–recapture project in Ottawa, Ontario, near the species’ northern limit, an adult female was captured on 27 April 2017. It had first been marked on 11 June 1983, when it was an adult with 17 growth rings on its plastron. Based on the number of growth rings at first capture, and the intervening time, this turtle is a minimum of 51 years old, setting a longevity record for the species. Ten individuals in this population were at least 30 years old when last captured, including a male at least 41 years old. Few of these turtles have grown measurably since being marked in 1983, and it is likely that these minimum ages are underestimates of actual ages.
Regaining Lost Protections: Status of the Revisions to the Canadian Fisheries Act
January 1, 2021The Fisheries Act (Act), a long-standing Act protecting fisheries in Canada, was changed in 2012 to redefine its central purpose to the management of fisheries in Canada. Along with this refocus were changes that appeared to reduce protections for habitat and all fish. After an outcry by scientists, Indigenous peoples, and environmental organizations, the Act was revised in 2019 to “restore lost protections” thought to have been lost in the 2012 changes. To a large degree most of the “lost protections” have been restored, while other portions of the 2012 Act have been maintained. Challenges remain under the amended Act in efficiently implementing development and conservation projects while achieving the newly clarified purpose of the Act—the conservation and protection of fish and fish habitat.
Restoring habitat for Monarch in eastern Ontario
May 7, 2019Increasingly, private landowners are interested in restoring areas of their property to provide improved habitat for Monarch and other pollinators. While there is abundant information on small-scale gardening with native plants, there is far less information available for restoration plantings at a larger scale. Here is a brief introduction for landowners in eastern Ontario interested in restoring an area of an acre or in a cost-effective way. More detailed information is in progress, so keep in touch for updates. Another great resource from the Xerces Society is Establishing Pollinator Meadows from Seed.
Restoring Pollinator Habitat on Rights-of-Way Workshop Summary Report—Highlights and What We Heard
February 20, 2020On February 20, 2020, the Canadian Wildlife Federation and Toronto Region Conservation Authority hosted a workshop for Rights-of-Way Managers, native seed suppliers and environmental non-profit groups.
Revisiting the challenge: perspectives on Canada’s freshwater fisheries policies three decades after the Pearse Report
June 23, 2022A seminal report by Peter H. Pearse (1988; Rising to the Challenge: A New Policy for Canada’s Freshwater Fisheries, Canadian Wildlife Federation, Ottawa) outlined 62 policy recommendations focused on the management of Canada’s inland fisheries. Over three decades later, freshwater ecosystems and inland fisheries in Canada are still facing similar challenges with many emerging ones that could not have been foreseen. Here, we reflect on the contemporary relevance of the Pearse Report and propose recommendations that policy makers should consider. Broadly, our recommendations are: (1) manage fishes, fisheries, and habitat using a holistic co-management framework, with clearly defined fishery jurisdictions and partnerships with Indigenous governments; (2) engage in transparent, inclusive, and agile research to support decision-making; (3) facilitate knowledge co-production, involving interdisciplinary projects with diverse groups of actors and sectors including Indigenous Peoples, anglers, policy makers, scientists/researchers, governments, and the public; (4) embrace technological advances to support freshwater fisheries stock assessment and management; and (5) align policy and management activities in Canada with global initiatives related to increasing the sustainability of inland fisheries. We advocate for an updated comprehensive report such as the Pearse Report to ensure that we embrace robust, inclusive, and sustainable management strategies and policies for Canada’s inland fisheries for the next 30 years. It is time to again rise to the challenge.
Survey of Chinook Salmon (Oncorhynchus tshawytscha) carcasses in Whitehorse, Yukon - 2017
January 1, 2017Carcass surveys are a useful tool for fisheries management, especially for anadromous fish such as Pacific salmon (Oncorhynchus spp.). They are widely used to inform managers on topics such as escapement, run characteristics, and pre-spawn mortality (DeWeber et al. 2017; Rawding et al. 2014; Murdoch et al. 2010). However, outside of spawning grounds and natal streams, carcass surveys have been used sparsely.
Survey of Chinook Salmon (Oncorhynchus tshawytscha) carcasses in Whitehorse, Yukon - 2018
January 1, 2018Carcass surveys can provide valuable information on escapement, population characteristics, and run timing in anadromous fish stocks. During the 2018 Chinook Salmon (Oncorhynchus tshawytscha) run in the upper Yukon River, carcass surveys were completed daily to provide preliminary information on egg deposition rates and spawning escapement of Chinook Salmon downstream of the Whitehorse Hydro Plant (WHP) and refine carcass survey methods.
Survey of Chinook Salmon (Oncorhynchus tshawytscha) carcasses in Whitehorse, Yukon - 2019
June 1, 2021Carcass surveys can provide valuable information on spawning success, escapement, population characteristics, and run timing in anadromous fish stocks. During the 2019 Chinook Salmon (Oncorhynchus tshawytscha) run, carcass surveys were completed approximately daily to provide information on egg retention and spawning escapement of upper Yukon River Chinook Salmon downstream of the Whitehorse Hydro Plant (WHP). Carcasses were assessed for sex, size, and origin, and the total number of eggs remaining in the body cavity was estimated volumetrically. Surveys were also completed in the Teslin River downstream of Johnson’s Crossing to determine whether egg retention rates observed in Whitehorse are similar to those observed in other nearby populations.
Survey of Chinook Salmon (Oncorhynchus tshawytscha) carcasses in Whitehorse, Yukon - 2020
June 1, 2021Carcass surveys can provide valuable information on spawning success, escapement, population characteristics, and run timing in anadromous fish stocks. During the 2020 Chinook Salmon (Oncorhynchus tshawytscha) run, carcass surveys were completed approximately daily to provide information on egg retention of upper Yukon River Chinook Salmon downstream of the Whitehorse Hydro Plant (WHP). Carcasses were assessed for sex, size, and origin, and the total number of eggs remaining in the body cavity was estimated volumetrically
The alarming state of freshwater biodiversity in Canada
June 28, 2021Little is known about the current state of freshwater biodiversity in Canada, one of the countries with the greatest amount of surface waters in the world. To address this knowledge gap, we compiled a list of all available assessments of conservation status for freshwater species (over 3000 taxa) and further evaluated the overall status of six distinct taxonomic groups, focusing on organisms reliant on fresh waters (i.e., aquatic plants, invertebrates (with a focus on freshwater mussels), fishes, herpetofauna (reptiles and amphibians), birds, and mammals). Overall, 11.7% of all freshwater species of plants and animals assessed were found to be “at risk” (i.e., listed as “Threatened”, “Endangered”, or “Extirpated”) and 17.9% identified as “Special Concern”. We found that 37.9% of species lacked sufficient data to enable their status to be assessed. Data gaps in Canada’s assessment of its freshwater species were most prevalent in invertebrates (excluding freshwater mussels). Given the alarming state of freshwater biodiversity in Canada, we conclude by providing recommendations that focus on evaluating temporal trends and informing conservation actions.
The recovery of North Atlantic right whales has been constrained by human-caused mortality
November 11, 2018Cockeron et al. 2018. The recovery of North Atlantic right whales has been constrained by human-caused mortality. - Comparison of population growth with Southern right whales, and the impacts of anthropogenic mortality.
Forests & Fields
Application of land use simulation in Western Boreal
Avoided ecological loss is an appropriate measure of conservation effectiveness, but challenging to measure because it requires consideration of counterfactual conditions. Land-use simulation is a well suited but under-utilized tool in this regard.
Bats & Neonics Report
The purpose of the review by Pierre Mineau and CWF’s Carolyn Callaghan is to examine the various lines of evidence that new systemic insecticides may be putting Canadian bats at risk. Specifically, this review investigates the risk and magnitude of neonicotinoid exposure for bats foraging in agricultural landscapes, and assess the resulting direct risk to bats by constructing a formal risk assessment following an exhaustive review of what is known currently about the mammalian toxicology of neonics. The indirect effects of neonicotinoid insecticides in bats will also be explored by reviewing the case for insect declines and the probable involvement of neonicotinoid insecticides in these declines.
Do turtle warning signs reduce roadkill?
October 1, 2019Roadkill is a serious threat for many species of freshwater turtles. One of the most common road mitigation tools is wildlife warning signs to alert drivers. These warning signs have commonly been used for large mammals, although there is little evidence that they are effective in reducing roadkill. We tested the effectiveness of turtle warning signs at four known roadkill hotspots along a provincial highway in eastern Ontario and compared the results with four control sites on a nearby major road in a before-after-control-impact (BACI) study. We found 30 dead turtles in the four hotspots in 2017 before the signs were installed and 27 in 2018 after the signs were installed. The number of turtles killed on the road after the signs were installed did not change significantly (χ21 = 1.1, P > 0.2). Although turtle warning signs may alert some drivers, they should not be considered a replacement for more effective road mitigation tools, such as wildlife fencing and crossing structures.
How Neonicotinoid Pesticides May Be Harming Bats
August 26, 2019There are over 1,300 bat species worldwide, 19 of which call Canada home. Our bats are incredibly important, not only to the environment but to the economy too. When the sun goes down, bats get to work eating the annoying pests in our backyards. They’re also extremely beneficial to the agricultural industry. In fact, bats save the agricultural industry in North America $3.7 billion every year.
Landscape factors influencing roost site selection by monarch butterflies Danaus plexippus during fall migration in Ontario, Canada
April 1, 2023Worldwide, insect populations are declining, and the eastern migratory group of the monarch butterfly Danaus plexippus in North America has not escaped this fate. The conservation of this iconic species is an international priority but requires knowledge of how monarchs interact with the landscape during different stages of the annual cycle. To better understand habitat needs of monarchs departing their core breeding range in southern Ontario, Canada, we examined how various landscape features influenced roost site selection during fall migration—an instrumental resource link between the breeding and wintering grounds. Using dedicated fall migration surveys along the Great Lakes coastlines and a citizen science dataset collected across all of Ontario, we evaluated the relationship between roost site occupancy and 18 landscape variables using a boosted regression tree (BRT) modelling approach. Results suggest that a closer distance to the Great Lakes, increased goldenrod Solidago spp. cover, moderate forest cover, rural road cover, and urban land cover are all important to roosting site selection. Our research provides important insights into the habitat characteristics of stopover sites, which will help guide future investigations and conservation actions to preserve monarch butterflies and their migratory phenomenon.
Restoring habitat for Monarch in eastern Ontario
May 7, 2019Increasingly, private landowners are interested in restoring areas of their property to provide improved habitat for Monarch and other pollinators. While there is abundant information on small-scale gardening with native plants, there is far less information available for restoration plantings at a larger scale. Here is a brief introduction for landowners in eastern Ontario interested in restoring an area of an acre or in a cost-effective way. More detailed information is in progress, so keep in touch for updates. Another great resource from the Xerces Society is Establishing Pollinator Meadows from Seed.
Restoring Pollinator Habitat on Rights-of-Way Workshop Summary Report—Highlights and What We Heard
February 20, 2020On February 20, 2020, the Canadian Wildlife Federation and Toronto Region Conservation Authority hosted a workshop for Rights-of-Way Managers, native seed suppliers and environmental non-profit groups.
The changing agricultural landscape in Canada’s Mixedwood Plains Ecozone (2011–2022) and the implications for biodiversity
The prairies and savannahs historically found in the Mixedwood Plains Ecozone have been largely converted into farmland, the dominant present-day land cover. Consequently, many species native to these grasslands have shifted to inhabiting suitable agricultural lands. More recently, agricultural intensification has led to the conversion of pastures and hay fields to annual crops, further removing habitat suitable for the persistence of grassland species. We quantified the shift from pasture and forage to annual crops as well as the dynamics among agricultural lands and other land covers in the Mixedwood Plains Ecozone, predicting biodiversity implications by providing a case study on Eastern Meadowlark (Sturnella magna (Linnaeus, 1758)). The total agricultural land area changed little over the study period, but area of pasture and forage decreased while row crop area increased. The loss of agricultural lands to urbanization was partly offset by the conversion of forests and wetlands; however, the farmland gained was of lesser agricultural quality than the farmland lost. Declines in Eastern Meadowlark abundance correlated significantly with carrying capacity loss, suggesting that habitat availability is a limiting factor for this species.We highlight the importance of land management policies tominimize the impacts of land conversion on biodiversity and agricultural production.
The Future of Wildlife Conservation and Resource Development in the Western Boreal Forest
A technical report on cumulative effects modeling of future land use scenarios
Lakes & Rivers
Assessing terrestrial movements of Eastern Musk Turtle (Sternotherus odoratus) using iNaturalist Canada
July 1, 2024Eastern Musk Turtle (Sternotherus odoratus) is known to be a highly aquatic species, yet it is occasionally found away from waterbodies. If such movements are common, then road mortality may pose a substantial risk to the species. We examined iNaturalist Canada observations of Eastern Musk Turtle on roads and found 15 in which individuals were >25 m from water. The median distance to the nearest permanent waterbody was 100 m (range 30–330 m). All observations that were ≥100 m from the nearest waterbody occurred from mid-July onward, suggesting that the movements were not related to nesting activity. At least under some circumstances, Eastern Musk Turtle can move >100 m away from waterbodies increasing the risk of road mortality.
Effects of rail infrastructure on Pacific salmon and steelhead habitat connectivity in British Columbia
February 1, 2024The effects of rail infrastructure on the connectivity of habitat for Chinook (Oncorhynchus tshawytscha), Coho (O. kisutch), Sockeye (O. nerka), Chum (O. keta), and Pink salmon (O. gorbuscha) and anadromous Rainbow Trout (O. mykiss) in British Columbia were estimated. Habitats upstream of major hydro dams lacking fishways were not considered. Natural habitat accessibility was modelled for each species based on swimming ability and stream gradient, excluding habitats upstream of steep gradients, large waterfalls, or areas with subsurface flows. Within these naturally accessible habitats, areas that may support spawning and rearing were identified using intrinsic potential models. Anthropogenic structures that may be barriers to fish movement were then overlaid to identify habitat that may be blocked. Similar estimates of lateral habitat fragmentation were made by modelling lateral habitat along the floodplain, overlaying rail-stream crossings and lines, and identifying areas that may be disconnected by them
Insights into Chinook salmon (Oncorhynchus tshawytscha) movement ecology in the terminal reaches of the upper Yukon River during the spawning migration
August 24, 2022Chinook salmon (Oncorhynchus tshawytscha (Walbaum, 1792)) from the upper Yukon River are highly unique, with some populations migrating nearly 3000 km to spawning habitat near the northern range limit for the species. We conducted a 4-year study to understand the behaviour of Chinook salmon in the terminal reaches of their migration by tagging salmon with acoustic and radio transmitters in Whitehorse, Yukon, Canada, ∼2800 km from the ocean. Various migration characteristics were quantified for Chinook salmon, including en route mortality, diel behaviour, migration rates, and homing patterns, and associations with salmon origin (wild vs. hatchery), sex, size, and migration timing were explored. Salmon had high survival to spawning grounds (>98%) and migrated throughout all hours of the day, with higher proportions of nighttime movements in a smaller spawning tributary than in the Yukon River mainstem. Migration rates were faster for larger salmon as well as latearriving salmon, which was likely necessary to ensure they had sufficient time and suitable conditions on spawning grounds to reproduce. Non-direct homing movements (e.g., tributary exploration) were more common in male salmon and considerably increased migration distance through the study area. Findings from this study may help to inform the complex international and inter-nation management of these increasingly threatened Chinook salmon populations
A contemporary estimate for the abundance of juvenile American Eel Anguilla rostrata attempting to migrate past a barrier in the Ottawa River
July 17, 2022American Eel (Anguilla rostrata) travels from the Sargasso Sea to fresh waters of eastern North America and back in a lifetime, and once provided one of the most abundant eel fisheries in the world. Many American Eel populations are now at risk worldwide. Dams act as barriers to the upstream migration of juvenile American Eels, which can be partially mitigated by installing eel ladders. To inform mitigation decisions and provide baseline data, the number of eels approaching barriers should be estimated; however, estimation is difficult for this now rare and cryptic species, especially in large rivers. In St. Lawrence and Ottawa River system, American Eels are among the largest and most fecund of the species, and local populations in the Ottawa River are almost entirely composed of large, female eels. American Eel in this area has declined to less than 1% of historic abundance, yet no local population estimates are available to inform recovery strategies and management actions. We, therefore, evaluated data from an unpublished study to estimate the abundance of American Eel attempting to migrate upstream past a barrier. American Eels (n = 339) were captured at the Carillon Generating Station over 36 days (July 12, 2010–August 17, 2010). Results were fit to the POPAN Jolly-Seber model in program MARK. Future studies could be improved by sampling throughout the migration season and deploying multiple traps spanning downstream features. While confidence intervals in the best-fitting model were wide, the estimate nonetheless provides a baseline to inform future work and management.
Revisiting the challenge: perspectives on Canada’s freshwater fisheries policies three decades after the Pearse Report
June 23, 2022A seminal report by Peter H. Pearse (1988; Rising to the Challenge: A New Policy for Canada’s Freshwater Fisheries, Canadian Wildlife Federation, Ottawa) outlined 62 policy recommendations focused on the management of Canada’s inland fisheries. Over three decades later, freshwater ecosystems and inland fisheries in Canada are still facing similar challenges with many emerging ones that could not have been foreseen. Here, we reflect on the contemporary relevance of the Pearse Report and propose recommendations that policy makers should consider. Broadly, our recommendations are: (1) manage fishes, fisheries, and habitat using a holistic co-management framework, with clearly defined fishery jurisdictions and partnerships with Indigenous governments; (2) engage in transparent, inclusive, and agile research to support decision-making; (3) facilitate knowledge co-production, involving interdisciplinary projects with diverse groups of actors and sectors including Indigenous Peoples, anglers, policy makers, scientists/researchers, governments, and the public; (4) embrace technological advances to support freshwater fisheries stock assessment and management; and (5) align policy and management activities in Canada with global initiatives related to increasing the sustainability of inland fisheries. We advocate for an updated comprehensive report such as the Pearse Report to ensure that we embrace robust, inclusive, and sustainable management strategies and policies for Canada’s inland fisheries for the next 30 years. It is time to again rise to the challenge.
Impact of rail crossings on passage of Pacific salmon and steelhead in the Fraser River basin
June 16, 2022We examined the potential impact of railway infrastructure on the ability of Chinook Salmon (Oncorhychus tschawytscha), Coho Salmon (O. kisutch), Sockeye Salmon (O. nerka) and steelhead (O. mykiss) within the Fraser River basin to access habitat with the potential to provide important spawning and/or rearing habitat by using intrinsic potential-based modelling. We estimate that up to 1015 km of aquatic habitat with the potential to support spawning and/or rearing may be blocked, representing up to 1.4% of Chinook Salmon, 5.6% of Coho Salmon, 0.5% of Sockeye Salmon, and 6.1% of steelhead total rearing habitat within the project study area and 1.0% of Chinook Salmon, 2.8% of Coho Salmon, 0.9% of Sockeye Salmon, and 0.9% of steelhead spawning habitat in the project study area. In total, an estimated 282 closed-bottom rail crossings are located on streams with the potential to support salmonid spawning and/or rearing habitat.
Developing a national level evidence-based toolbox for addressing freshwater biodiversity threats
March 30, 2022Freshwater biodiversity is in a state of crisis. The recent development of a global emergency recovery plan to “bend the curve” for freshwater biodiversity lacks the necessary details for implementation in a regional context. Using Canada as an example, we describe a toolbox intended to equip decision-makers and practitioners with evidence-based tools for addressing threats to freshwater biodiversity. The toolbox includes two rubric-based scoring tools to inform users about the level of the reliability (e.g., transparent methods, critical appraisal) and relevancy to Canadian freshwater systems (e.g., habitat, species) of an evidence synthesis. Those scoring tools were applied to 259 evidence syntheses, also included in the toolbox, across fifty freshwater management actions. Habitat Creation, Invasive Species Removal, and Revegetation were found to have reliable evidence syntheses but there remain several actions for which the syntheses are not robust and where the evidence base is unreliable. We suggest the need for more rigorously conducted empirical tests of freshwater management actions, further evidence synthesis, and clearer conveyance of implications for decision-makers and practitioners.
Canadian Aquatic Barriers Database Overview
March 1, 2022All Canada’s aquatic barrier and connectivity information in one place – easily and openly accessible! Freshwater aquatic connectivity is an increasingly important, but underdeveloped area of focus in the study of ecosystem processes and conservation efforts at a national scale in Canada. Barriers to aquatic connectivity can include manmade infrastructure such as dams, weirs, and stream crossings (e.g., culverts), as well as natural features such as waterfalls. These include both barriers in the longitudinal plane (i.e., upstream-downstream), as well as lateral barriers disconnecting rivers and lakes from their riparian wetlands and floodplains. These barriers within freshwater systems limit the movements of aquatic species, many of which rely on annual migrations within or between freshwater and marine ecosystems to complete their life cycles, and disrupt ecological process including nutrient cycling, sediment flows, and temperature regulation.
Assessing a proponent-driven process for endangered species threat mitigation: Ontario’s Endangered Species Act, American Eel, and hydropower
February 10, 2022American Eel (Anguilla rostrata) were used as a case study to assess whether Ontario’s Endangered Species Act proponent-driven regulatory approach resulted in successful imperilled species management outcomes. American Eel observation databases and proponent-prepared mitigation plans and monitoring data were used to assess whether: (i) facilities within the distribution range were registered, (ii) effects monitoring protocols were adequate to evaluate adverse effects of facilities, (iii) proponents implemented mitigation actions that followed best management practices (BMPs), and (iv) effectiveness monitoring designs were adequate to evaluate effectiveness of mitigation actions. Less than half of the facilities (8 of 17) within the extant species range were registered. Few eels were observed at each facility, precluding proponents from effectively evaluating the facilities’ effects. Mitigation actions following BMPs were only implemented for eel out-migration at three facilities. Half of the registered facilities implemented effectiveness monitoring, but experimental designs did not follow best practices and standards. To improve this proponent-driven approach, regulators could reduce ambiguity in regulation language and provide clearer, quantitative requirements for facility registration, effects monitoring, mitigation actions, and effectiveness monitoring. Proponents could improve monitoring efforts to establish species occurrence and generate baseline data to measure facility effects and mitigation action effectiveness.
Bright spots for inland fish and fisheries to guide future hydropower development
January 24, 2022Hydropower production is one of the greatest threats to fluvial ecosystems and freshwater biodiversity. Now that we have entered the Anthropocene, there is an opportunity to reflect on what might constitute a ‘sustainable’ Anthropocene in the context of hydropower and riverine fish populations. Considering elements of existing practices that promote favorable social-ecological outcomes (i.e., ‘bright spots’) is timely given that there are plans to expand hydropower capacity in previously undammed rivers, intensify dam development in some of the world's largest river systems, and re-license existing facilities. We approach this from a pragmatic perspective: for the foreseeable future, hydropower will likely remain an important source of renewable electricity. To offer support for moving toward a more ‘sustainable’ Anthropocene, we provide syntheses of best practices during the siting, design, construction, operation, and compensation phases of hydropower development to minimize impacts on inland fish. For each phase, we offer positive examples (or what might be considered ‘bright spots’) pertaining to some of the approaches described within our syntheses, acknowledging that these projects may not be viewed as without ecological and (or) societal detriment by all stakeholders. Our findings underscore the importance of protecting critical habitat and free-flowing river reaches through careful site selection and basinscale planning, infrastructure designs that minimize reservoir effects and facilitate safe passage of fish, construction of hydropower plants using best practices that minimize long-term damage, operating guidelines that mimic natural flow conditions, and compensation that is lasting, effective, inclusive, and locally relevant. Learning from these ‘bright spots’ may require engagement of diverse stakeholders, professionals, and governments at scales that extend well beyond a given site, river, or even basin. Indeed
Horsefly River Watershed Secwepemcúl’ecw, Connectivity Remediation Plan: 2021 - 2040
August 1, 2021This plan represents the culmination of a collaborative planning process undertaken in the Horsefly River watershed over many months of work with a multi-partner planning team of individuals and groups passionate about the conservation and restoration of freshwater ecosystems and the species they support. Plan development was funded by the BC Salmon Restoration and Innovation Fund, Canada Nature Fund for Aquatic Species at Risk, and the RBC Bluewater Project. We were fortunate to benefit from the feedback, guidance, and wisdom of many groups and individuals who volunteered their time throughout this process — this publication would not have been possible without the engagement of our partners and the planning team (
Lower Nicola River Watershed, Connectivity Remediation Plan: 2021 - 2031
August 1, 2021This plan represents the culmination of a collaborative planning process undertaken in the Lower Nicola River watershed over many months of work with a multi-partner planning team of individuals and groups passionate about the conservation and restoration of freshwater ecosystems and the species they support. Plan development was funded by the BC Salmon Restoration and Innovation Fund, Canada Nature Fund for Aquatic Species at Risk, and the RBC Bluewater Project. We were fortunate to benefit from the feedback, guidance, and wisdom of many groups and individuals who volunteered their time throughout this process — this publication would not have been possible without the engagement of our partners and the planning team
Bulkley River Watershed (Laxyip | Wedzin Kwah): Connectivity Remediation Plan: 2021 - 2031
August 1, 2021This plan represents the culmination of a collaborative planning process undertaken in the Bulkley River watershed over many months of work with a multi-partner planning team of individuals and groups passionate about the conservation and restoration of freshwater ecosystems and the species they support. Plan development was funded by the BC Salmon Restoration and Innovation Fund and the RBC Bluewater Project.
The alarming state of freshwater biodiversity in Canada
June 28, 2021Little is known about the current state of freshwater biodiversity in Canada, one of the countries with the greatest amount of surface waters in the world. To address this knowledge gap, we compiled a list of all available assessments of conservation status for freshwater species (over 3000 taxa) and further evaluated the overall status of six distinct taxonomic groups, focusing on organisms reliant on fresh waters (i.e., aquatic plants, invertebrates (with a focus on freshwater mussels), fishes, herpetofauna (reptiles and amphibians), birds, and mammals). Overall, 11.7% of all freshwater species of plants and animals assessed were found to be “at risk” (i.e., listed as “Threatened”, “Endangered”, or “Extirpated”) and 17.9% identified as “Special Concern”. We found that 37.9% of species lacked sufficient data to enable their status to be assessed. Data gaps in Canada’s assessment of its freshwater species were most prevalent in invertebrates (excluding freshwater mussels). Given the alarming state of freshwater biodiversity in Canada, we conclude by providing recommendations that focus on evaluating temporal trends and informing conservation actions.
Survey of Chinook Salmon (Oncorhynchus tshawytscha) carcasses in Whitehorse, Yukon - 2020
June 1, 2021Carcass surveys can provide valuable information on spawning success, escapement, population characteristics, and run timing in anadromous fish stocks. During the 2020 Chinook Salmon (Oncorhynchus tshawytscha) run, carcass surveys were completed approximately daily to provide information on egg retention of upper Yukon River Chinook Salmon downstream of the Whitehorse Hydro Plant (WHP). Carcasses were assessed for sex, size, and origin, and the total number of eggs remaining in the body cavity was estimated volumetrically
Assessing the Fate of Returning upper Yukon River Chinook Salmon - 2020
June 1, 2021- Fall back (or over shoot) after passing the Whitehorse Hydro Plant was substantial (31%) compared to previous years of study - Many fish migrating into Michie Creek ventured to the uppermost reaches of the creek and even Michie Lake - Recovery of a tagged female carcass revealed successful egg deposition in the Yukon River mainstem above the WHP
Survey of Chinook Salmon (Oncorhynchus tshawytscha) carcasses in Whitehorse, Yukon - 2019
June 1, 2021Carcass surveys can provide valuable information on spawning success, escapement, population characteristics, and run timing in anadromous fish stocks. During the 2019 Chinook Salmon (Oncorhynchus tshawytscha) run, carcass surveys were completed approximately daily to provide information on egg retention and spawning escapement of upper Yukon River Chinook Salmon downstream of the Whitehorse Hydro Plant (WHP). Carcasses were assessed for sex, size, and origin, and the total number of eggs remaining in the body cavity was estimated volumetrically. Surveys were also completed in the Teslin River downstream of Johnson’s Crossing to determine whether egg retention rates observed in Whitehorse are similar to those observed in other nearby populations.
Assessing the Fate of Returning upper Yukon River Chinook Salmon - 2019
June 1, 2021- This is the first of the three years of this study that fish have neither terminated in the Upper M’Clintock River above the confluence with Michie Creek nor in Wolf Creek. - Two fish terminated in the Southern Lakes (Marsh Lake and Tagish Lake south of Tutshi) with a potential third fish having terminated in Marsh Lake - Unique terminal locations were identified in Michie Creek using manual tracking
Assessing the fate of returning upper Yukon River Chinook salmon (2017-2020)
May 18, 2021Chinook salmon (Oncorhynchus tshawytscha) from the Upper Yukon River have faced severe declines relative to their estimated abundances several decades ago. To further our understanding of Chinook salmon spawning locations in this area, and potential factors limiting the recovery of this population, we completed a 4-year telemetry study from 2017-2020. Efforts were focused on understanding the effectiveness of the Whitehorse Rapids Fishladder at allowing salmon to pass upstream of the Whitehorse Hydro Plant. To answer these questions, a telemetry array was deployed throughout the upper Yukon River and supporting tributaries upstream of Lake Laberge, YT. Salmon of both wild and hatchery origin were gastrically implanted with acoustic/radio transmitters at the fish ladder viewing chamber or downstream following gill net capture to evaluate passage success and subsequent spawning locations. Over the course of four years, a total of 171 tagged salmon passed upstream of the Whitehorse Hydro Plant with 78% terminating in the Michie Creek - M’Clintock River system, with the remainder terminating in Wolf Creek, the Yukon River mainstem, the Takhini River, and the Southern Lakes. Salmon tagged below the hydro plant that approached the fish ladder often did not pass through the structure. Salmon ceased upstream migration at multiple points within the ladder, including the viewing chamber where a gate must be manually lifted by staff to allow salmon passage. Findings from this work may be used to inform future spawning ground surveys, restoration actions, and design and operational changes at the Whitehorse Rapids Fishladder.
Breaking Down Barriers: A Practitioners' Guide to Watershed Connectivity Remediation Planning
May 7, 2021This guide outlines methods for assessing barriers to fish passage within a watershed and strategically planning for their remediation. It is based on the Conservation Standards, and describes processes to engage local partners, compile and analyze data, set connectivity goals, and identify strategic actions to achieve these goals. This process helps to ensure that the most important barriers are identified and remediated, focusing conservation efforts so that the greatest benefits are achieved.
Mobilizing practitioners to support the Emergency Recovery Plan for freshwater biodiversity
May 1, 2021Freshwater biodiversity loss is one of the greatest environmental threats in our changing world. Although declines have been reported extensively in the literature, much less attention has been devoted to solving the freshwater biodiversity crisis relative to other ecosystems. The recently proposed Emergency Recovery Plan for Freshwater Biodiversity (Tickner et al., 2020, BioScience, 70 (4), 330–342) outlines an ambitious but necessary set of overarching actions that can help “bend the curve” for freshwater biodiversity declines. This plan is timely given the present opportunity to adjust freshwater biodiversity targets in
Project Review Under Canada’s 2012 Fisheries Act: Risky Business for Fisheries Protection
March 1, 2021Canada's Fisheries Act provides essential protection for fish and their habitat. To manage thousands of projects a year, Fisheries and Oceans Canada implements a risk-based framework requiring authorization and offsetting for the highest risk projects. Projects considered lower risk proceed via letters of advice. Following changes to the Act in 2012, there were concerns about transparency and cumulative effects of low-risk projects. We used access to information requests to obtain documents and reviewed the department’s 2012–2019 risk-based framework. Projects reviewed in Manitoba in 2016 were examined and the amount of permanent alteration and destruction approved without authorization was quantified (23,881 m2 and 6,768 m2, respectively). The risk-based framework focused reviews and regulatory decisions on project-by-project effects, rather than cumulative risks
Canadian Aquatic Barriers Database: Project Background and Overview
January 28, 2021Freshwater aquatic connectivity is an increasingly important, but underdeveloped area of focus in the study of ecosystem processes and conservation efforts at a national scale in Canada. Barriers to aquatic connectivity can include manmade infrastructure such as dams, weirs, culverts, and roadstream crossings, as well as natural features such as waterfalls. These include both barriers in the longitudinal plane (i.e., upstream-downstream), as well as lateral barriers disconnecting rivers and lakes from their riparian wetlands and floodplains. These barriers within freshwater systems limit the movements of aquatic organisms, many of which rely on annual migrations within or between freshwater and marine ecosystems to complete their life cycles, and disrupt ecological process including nutrient cycling, sediment flows, and temperature regulation.
Apparent winterkill of Painted Turtle
January 1, 2021Around the margin of an artificial pond in Ottawa, Ontario, we found 25 Painted Turtles (Chrysemys picta) that appeared to have died over the course of two winters (17 during the first winter and eight during the second). We examined meteorological data to try to determine the cause of the mortality. Summer and fall rains were only slightly below normal in both years, suggesting water levels should have been close to normal. The winter air temperature was warmer than normal and winter snowfall was slightly above normal in both years. Unseasonable weather does not appear to be responsible for the winter mortality and the pond’s maximum depth of 1.7 m should prevent freezing to the bottom. It is possible that the artificial nature of the pond creates suboptimal overwintering habitat, rendering the site an ecological trap; however, there is no direct evidence to support this theory. It is also possible that winter mortality of turtles is widespread at temperate wetlands, but that dead turtles were more detectable at this site because of the bare shoreline around the pond. Winter mass mortality events, if common, may represent an additional threat to turtle populations, which are declining from various anthropogenic threats.
Fate of translocated American eel (Anguilla rostrata) in the lower Ottawa River and passage behavior at a multichannel barrier
January 1, 2021American eel (Anguilla rostrata) is considered endangered under the IUCN's red list. Hydropower facilities are considered a significant threat to American eel, impacting both the outmigration of adults and upstream migration of juveniles. To overcome upstream passage issues, juvenile eels may be trapped and transported around barriers as a mitigation strategy, though few studies have evaluated the efficacy of this approach. To understand the fate of transported eels, we monitored posttranslocation movements in a 110-km reach of the Ottawa River bounded by two hydropower facilities: Carillon Hydroelectric Generating Station (lower barrier) and Chaudière Falls Hydroelectric Facility (upper barrier). Additionally, we assessed the approach behavior of eels that reached the upper barrier, a multichannel facility, to assess potential fishway locations. To assess these objectives, 40 juvenile eels (440–640 mm) were implanted with acoustic transmitters and were transported and released either just upstream (6 km) of the lower barrier or just downstream of the upper barrier (2 km), approximately, 60 and 166 km from the capture site, respectively. Over the three-month study period, 78% of tagged eels remained upstream of the lower barrier. Of the nine eels that returned downstream of the lower barrier, seven were from the downstream release site; however, the proportion of eels that returned downstream of the lower barrier did not differ significantly between release sites. One eel passed the upper barrier despite no existing fish-passage structures. At the upper barrier, most eels visited just one of the five channels, suggesting that more than one passage structure may be necessary to allow eels entering different channels to pass upstream of the barrier. Findings from this work will help inform passage efforts for American eel, particularly in the Ottawa River where eel populations have declined severely from their historic abundance.
High egg retention in Chinook Salmon Oncorhynchus tshawytscha carcasses sampled downstream of a migratory barrier
January 1, 2021Barriers in rivers have the potential to severely decrease functional connectivity between habitats. Failure to pass barriers and reach natal spawning habitat may compromise individual reproductive success, particularly for semelparous, philopatric species that rely on free-flowing rivers to reach natal habitat during their once-in-alifetime spawning migrations. To investigate the consequences of in-river barriers on fish spawning success, we quantified egg retention and spawning effort (caudal fin wear) in female Chinook Salmon Oncorhynchus tshawytscha carcasses collected downstream of the Whitehorse Hydro Plant on the upper Yukon River and at a nearby free-flowing tributary (Teslin River) from 2018 to 2020 (2900 km migrations). Previous studies have demonstrated that a large proportion of fish attempting to reach spawning locations upstream of the hydro plant fail to pass the associated fishway. We estimated nearly all female salmon failing to pass the hydro plant attempted spawning in non-natal habitat downstream, but that these females retained 34% of their total fecundity compared to 6% in females from the free-flowing river. Females downstream of the hydro plant also had lower wear on their caudal fin, a characteristic that was correlated with increased egg deposition. Egg retention did not vary across years with different run sizes, and we propose that egg retention downstream of the hydro plant was not driven by density-dependent mechanisms. Findings from this work indicate that female Chinook Salmon can still deposit eggs following failed fish passage and failure to reach natal spawning sites, though egg retention rates are considerably higher and uncertainties remain about reproductive success. We encourage researchers to incorporate carcass surveys into fish passage evaluations for semelparous species to fully account for consequences of failed passage.
Regaining Lost Protections: Status of the Revisions to the Canadian Fisheries Act
January 1, 2021The Fisheries Act (Act), a long-standing Act protecting fisheries in Canada, was changed in 2012 to redefine its central purpose to the management of fisheries in Canada. Along with this refocus were changes that appeared to reduce protections for habitat and all fish. After an outcry by scientists, Indigenous peoples, and environmental organizations, the Act was revised in 2019 to “restore lost protections” thought to have been lost in the 2012 changes. To a large degree most of the “lost protections” have been restored, while other portions of the 2012 Act have been maintained. Challenges remain under the amended Act in efficiently implementing development and conservation projects while achieving the newly clarified purpose of the Act—the conservation and protection of fish and fish habitat.
Backgrounder: CWF Fish Passage Projects 2019-2020
November 18, 2020The Canadian Wildlife Federation (CWF) is pleased to release details of 2019-2020 projects restoring fish passage in B.C. thanks to funding from the provincial and federal governments and the support of multiple partners.
Angler interactions with American eel (Anguilla rostrata): Exploring perspectives and behaviors toward an imperiled fish
November 5, 2020As aquatic biodiversity continues to decline, recreational anglers are interacting more frequently with imperiled species. As a result, management strategies must be developed to balance fisheries management and conservation objectives. Understanding the human dimensions of these encounters is important for both fisheries management and conservation objectives, because decisions made by anglers have a direct impact on the fish. This work explores angler perspectives and behaviors toward American Eel (Anguilla rostrata), a species listed as Endangered in the Canadian province of Ontario and globally (IUCN Red Listed as Endangered), and not typically targeted by recreational anglers in Ontario. Interviews with 48 anglers on the Ottawa River revealed that almost half had captured an eel at some point, but few had intentionally killed eels (in each case prior to the eel’s Endangered status listing in Ontario). However, a large proportion of respondents were, or would be, uncomfortable handling eels if captured, and almost half of respondents declared a limited or lack of knowledge about the species. These findings suggest that discomfort around eels and limited knowledge about their value (both ecological and economical) do not cause direct harm to eels but may impede full public support for conservation of the species.
Establishing best practices for implanting Passive Integrated Transponder (PIT) tags in American Eel (Anguilla rostrata)
March 1, 2020Workshop Report Ontario Species at Risk Stewardship Program Project #18-19-CWF
Does catch-and-release angling pose a threat to American eel? A hooking mortality experiment
January 16, 2020Incidental capture of protected fishes usually calls for immediate release, however, post-release survival has not been investigated for many protected species. The American eel Anguilla rostrata is an example of an imperiled species that is incidentally captured by recreational anglers, but for which the impacts of catch and release are unknown. In this study, we examined the short-term (7 d) mortality and injury of American eels (n = 207) following simulated catch-and-release scenarios (involving manually embedded hooks) in a controlled experiment. Specifically, we compared the effects of cutting the line versus removing the hook, as well as shallow versus deep hooking, in holding tanks. No mortalities occurred in any of the groups during a 7 d monitoring period, and most eels exhibited little to mild injury. A high degree of hook shedding occurred in groups where the hook was shallowly embedded. Hooking depth was significantly related to hook-shedding rate, with 93.7% of hooks shed in the shallow-hook−line-cut group compared to 71.8% of hooks shed in the deep-hook−line-cut group. Our results suggest that recreationally captured American eels may be relatively resilient to catch and release, but validation of these results in a field setting is recommended.
The effectiveness of spawning habitat creation or enhancement for substrate‑spawning temperate fish: a systematic review
August 19, 2019Habitat is the foundation for healthy and productive fisheries. For fish that require substrate for spawning, lack of appropriate spawning substrate is inherently limiting and a lack of access to suitable spawning habitat will lead to population collapse. To ensure management resources are being allocated wisely and conservation targets are being achieved, there is an increased need to consider the effectiveness of techniques to enhance or create habitat that has been lost.
Horizon scan of conservation issues for inland waters in Canada
March 22, 2019Horizon scanning is a systematic approach increasingly used to explore emerging trends, issues, opportunities, and threats in conservation. We present the results from one such exercise aimed at identifying emerging issues that could have important scientific, social, technological, and managerial implications for the conservation of inland waters in Canada in the proximate future. We recognized six opportunities and nine challenges, for which we provide research implications and policy options, such that scientists, policy makers, and the Canadian society as a whole can prepare for a potential growth in each of the topic areas we identified. The issues spanned a broad range of topics, from recognizing the opportunities and challenges of community-enabled science and the need to consider the legal rights of nature, to the likely increase of pharmaceuticals in wastewater due to an aging population. These issues represent a first baseline that could help decision makers identify and prioritize efforts while simultaneously stimulate new research avenues. We hope our horizon scan will pave the way for similar exercises related to the conservation of biodiversity in Canada.
American Eel Listing Decision Letter, March 18, 2019
March 18, 2019We are writing to express concern regarding the long delay in attaining a decision by Cabinet on whether or not to add American Eel to Schedule 1 of the Species at Risk Act as a Threatened species as per the 2012 COSEWIC assessment. Our position is that American Eel should be listed. DFO’s public comment period closed two years ago yesterday, yet no proposed listing decision has been published in Canada Gazette Part I. We understand that DFO is in the final stages of developing listing advice, but the timeline to a final listing decision remains unclear. This uncertainty continues to hinder the creation of meaningful partnerships to advance the recovery of American Eel.
Diel Feeding and Movement Activity of Northern Snakehead
January 1, 2019Understanding the diel activity of a species can shed light on potential interactions with other species and inform management practices. To understand the diel activity of Northern Snakehead Channa argus, feeding habits and movement patterns were observed. Two hundred seventy-three Northern Snakehead were captured by boat electrofishing during May and June of 2007 and 2008.
Assessing occupancy of freshwater fishes in urban boat slips of Toronto Harbour
October 8, 2018Hardening of natural shorelines in urban aquatic ecosystems can result in a loss of fish habitat and productivity. The north shore of Toronto Harbour (Lake Ontario) has been converted to hardened boat slips for commercial, industrial and recreational purposes, but its potential utility as fish habitat has not been evaluated. The objective of this study was to determine whether fish frequented and utilized four slips in the Inner Harbour of Toronto.
Survey of Chinook Salmon (Oncorhynchus tshawytscha) carcasses in Whitehorse, Yukon - 2018
January 1, 2018Carcass surveys can provide valuable information on escapement, population characteristics, and run timing in anadromous fish stocks. During the 2018 Chinook Salmon (Oncorhynchus tshawytscha) run in the upper Yukon River, carcass surveys were completed daily to provide preliminary information on egg deposition rates and spawning escapement of Chinook Salmon downstream of the Whitehorse Hydro Plant (WHP) and refine carcass survey methods.
Assessing the Fate of Returning Upper Yukon River Chinook Salmon - 2018
January 1, 2018A 50-receiver acoustic telemetry array was deployed throughout the Upper Yukon River and supporting tributaries to identify spawning locations of Chinook Salmon (Oncorhynchus tshawytscha) upstream of Lake Laberge, YT.
Joint Letter for the American Eel Timeline, February 26, 2017
February 24, 2017We are writing regarding your response, dated September 13th, 2016, to the letter sent by the Canadian Wildlife Federation, Ottawa Riverkeeper, Ontario Rivers Alliance and Ontario Nature on August 22nd, 2016 expressing concern over the delay by the Province of Ontario in producing a government response statement (GRS) following publication of the Recovery Strategy for American Eel. In your response, you indicated that a draft would be ready for public consultation this winter.
The future of fish passage science, engineering, and practice
February 1, 2017Much effort has been devoted to developing, constructing and refining fish passage facilities to enable target species to pass barriers on fluvial systems, and yet, fishway science, engineering and practice remain imperfect. In this review, 17 experts from different fish passage research fields (i.e., biology, ecology, physiology, ecohydraulics, engineering) and from different continents (i.e., North and South America, Europe, Africa, Australia) identified knowledge gaps and provided a roadmap for research priorities and technical developments. Once dominated by an engineering-focused approach, fishway science today involves a wide range of disciplines from fish behaviour to socioeconomics to complex modelling of passage prioritization options in river networks. River barrier impacts on fish migration and dispersal are currently better understood than historically, but basic ecological knowledge underpinning the need for effective fish passage in many regions of the world, including in biodiversity hotspots (e.g., equatorial Africa, South-East Asia), remains largely unknown. Designing efficient
Survey of Chinook Salmon (Oncorhynchus tshawytscha) carcasses in Whitehorse, Yukon - 2017
January 1, 2017Carcass surveys are a useful tool for fisheries management, especially for anadromous fish such as Pacific salmon (Oncorhynchus spp.). They are widely used to inform managers on topics such as escapement, run characteristics, and pre-spawn mortality (DeWeber et al. 2017; Rawding et al. 2014; Murdoch et al. 2010). However, outside of spawning grounds and natal streams, carcass surveys have been used sparsely.
Assessing the Fate of Returning Upper Yukon River Chinook Salmon - 2017
January 1, 2017To assess the behavior of Chinook Salmon (Oncorhynchus tshawytscha) migrating past the Whitehorse Hydro Plant (WHP), 68 fish were gastrically implanted with acoustic transmitters in 2017. Twenty acoustic receivers were deployed between Lake Laberge and the spawning grounds in the Michie Creek – M’Clintock River system. Forty-eight fish were captured in the Whitehorse Rapids Fishladder viewing chamber, acoustically tagged, and released there.
Telemetry-Determined Habitat Use Informs Multi-Species Habitat Management in an Urban Harbour
September 26, 2016Widespread human development has led to impairment of freshwater coastal wetlands and embayments, which provide critical and unique habitat for many freshwater fish species. This is particularly evident in the Laurentian Great Lakes, where such habitats have been severely altered over the last century as a result of industrial activities, urbanization, dredging and infilling. In Toronto Harbour, extensive restoration efforts have been directed towards improving the amount and quality of aquatic habitat, especially for fishes.
Joint Letter for the American Eel, August 22, 2016
August 22, 2016We are writing to express concern over the unlawful delay by the Province of Ontario in producing a government response statement following publication of the recovery strategy for American Eel. This recovery strategy was published on November 22nd, 2013, nearly five months past the legal deadline under Ontario’s Endangered Species Act (ESA). As of today, the response statement is now two years overdue. The Canadian Wildlife Federation wrote you regarding this issue on July 12th, 2016, but to date has received only an acknowledgement of the letter. The lack of communication from the Ontario Government regarding the cause of this delay and when the response statement will be issued is of great concern.
Pathways of fish invasions in the Mid-Atlantic region of the United States
March 18, 2016Non-native fish introductions are a major threat to biodiversity and fisheries, and occur through numerous pathways that vary regionally in importance. A key strategy for managing invasions is to focus prevention efforts on pathways posing the greatest risk of future introductions. We identified high-risk pathways for fish establishment in the Mid-Atlantic region of the United States based on estimates of relative probability of establishment among pathways and records of previous introductions, which were considered in the context of emerging socioeconomic trends. We used estimates of propagule pressure, species’ environmental tolerance, and size of species pool to assess the risk of establishment by pathway.
Restoring aquatic ecosystem connectivity requires expanding inventories of both dams and road crossings
A key challenge in aquatic restoration efforts is documenting locations where ecological connectivity is disrupted in water bodies that are dammed or crossed by roads (road crossings). To prioritize actions aimed at restoring connectivity, we argue that there is a need for systematic inventories of these potential barriers at regional and national scales. Here, we address this limitation for the North American Great Lakes basin by compiling the best available spatial data on the locations of dams and road crossings. Our spatial database documents 38 times as many road crossings as dams in the Great Lakes basin, and case studies indicate that, on average, only 36% of road crossings in the area are fully passable to fish. It is therefore essential that decision makers account for both road crossings and dams when attempting to restore aquatic ecosystem connectivity. Given that road crossing structures are commonly upgraded as part of road maintenance, many opportunities exist to restore connections within aquatic ecosystems at minimal added cost by ensuring upgrade designs permit water flow and the passage of fish and other organisms. Our findings highlight the necessity for improved dam and road crossing inventories that traverse political boundaries to facilitate the restoration of aquatic ecosystem connectivity from local to global scales.
Record longevity of a Spotted Turtle
Turtles are known for their longevity, but the maximum life span for many species remains unknown. Spotted Turtle (Clemmys guttata) can live for more than 30 years in the wild, but typical or maximum longevity has not been confirmed. As part of a long-term mark–recapture project in Ottawa, Ontario, near the species’ northern limit, an adult female was captured on 27 April 2017. It had first been marked on 11 June 1983, when it was an adult with 17 growth rings on its plastron. Based on the number of growth rings at first capture, and the intervening time, this turtle is a minimum of 51 years old, setting a longevity record for the species. Ten individuals in this population were at least 30 years old when last captured, including a male at least 41 years old. Few of these turtles have grown measurably since being marked in 1983, and it is likely that these minimum ages are underestimates of actual ages.
