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Similar to many freshwater ecosystems, the Laurentian Great Lakes of North America have undergone numerous anthropogenic stressors resulting in considerable loss of biodiversity and habitat. Among Great Lakes fishes, the coregonine sub-family has endured the most extensive declines, including extinction of several species (Coregonus johannae, C. alpenae, and C. kiyi orientalis) and at least 10 instances of local extirpations of other species (C. nigripinnis, C. reighardi, C. zenithicus, C. hoyi, and C. artedi) across all 5 lakes, much of which occurred prior to the 1960s owing to overfishing, interactions with non-indigenous species, and habitat loss. Despite these declines, no federal-, provincial-, or state-mandated actions were ever implemented to conserve coregonine diversity, potentially because so much of the coregonine declines occurred prior to the enactment of federal conservation legislation. Possible explanations for inaction since enactment of that legislation include insufficient data on biological vulnerability or threats, unresolved taxonomy, and limited support from the fishery management agencies and their stakeholders prior to the 2000s. In recent decades, however, several fishery management agencies have undertaken efforts to re-introduce coregonine diversity. These efforts helped lead to development of a science-based framework to restore coregonines that was universally endorsed by fishery managers representing eight U.S. states, four U.S. tribal organizations, and the province of ON, Canada, in May 2018. The basin-wide framework is based on principles of conservation biology and adaptive management. We describe details of its key steps, including planning, restoring, and evaluating, while also describing recent implementation efforts to develop methods, improve available resources, and enhance coordination across the basin. Although our paper describes a regional effort to restore native coregonines, our adaptive-management approach could be used by other multi-agency stakeholders seeking to conserve or restore native fishes. [ABSTRACT FROM AUTHOR]

Amid Earth's ongoing sixth mass extinction event, numerous measures have been proposed to recover the populations of species at risk of extinction. However, the methods and objectives of different species' recovery plans sometimes conflict with each other, causing a conundrum we refer to as recovery–action antagonism. Recovery–action antagonism reduces the cost‐effectiveness of conservation programs and can increase the extinction risk of nontarget species. We describe a method to identify interactions between recovery actions, including antagonisms proposed for different at‐risk species in a given location. The method includes a process to evaluate potential drivers of recovery‐action antagonism and other interaction types using principal coordinates analysis and distance‐based redundancy analysis. We illustrate various applications of the method through case studies performed in Pelee Island and Rouge National Urban Park, two biodiverse areas in Ontario, Canada. Potential antagonism was identified between 1.5% (Pelee) and 5% (Rouge) of the evaluated recovery actions. Although the rate of antagonism was low in our case studies, the method allows the identification of a variety of interactions, which can help to prioritize similar and complementary actions that will benefit a large number of species while minimizing actions that may have competing outcomes. [ABSTRACT FROM AUTHOR]

Aim: Recent studies have found that local‐scale plots measured through time exhibit marked variation in the change in species richness. However, the overall effect often reveals no net change. Most studies to date have been agnostic about the identities of the species lost/gained and about the processes that might lead to these changes. Generalist traits might be crucial in allowing species to colonize new plots or remain resilient in situ, whereas environmental filtering might remove specialists. We test whether plots are changing in species richness, whether they are becoming more similar (i.e., becoming homogenized) through time and whether several generalist traits can predict gains or losses from local plots. Location: Canada. Time period: 1945–2015. Major taxa studied: Two hundred and sixty‐five species of butterflies. Methods: We measured change in species richness and pairwise beta diversity across 96 well‐sampled 10 km × 10 km plots across Canada between two time periods: 1945–1975 and 1985–2015. We looked at the effects of wing span, mobility, dietary breadth and range size on the number of grid cells each species gained and lost between time periods. Results: We observed a slight increase in plot‐level species richness, and that these communities are becoming homogenized through time. We note that most butterfly species in Canada have large North American ranges. The species with the widest ranges are better able to colonize new plots than species with narrower ranges, but also experience higher frequencies of local extinctions. In sum, the median range size of species within a plot increased through time. Main conclusions: We highlight that, even when local species richness exhibits very little change, other potentially important changes in biodiversity can occur, such as geographical homogenization attributable to the colonization dynamics of species that are already widely distributed. Such patterns can reconcile observed global losses of species with the simultaneous lack of change in local diversity. [ABSTRACT FROM AUTHOR]

Endangered species legislation in the United States and Canada aims to prevent extinction of species, in part by designating and protecting critical habitats essential to ensure survival and recovery. These strict laws prohibit adverse modification or destruction of critical habitat, respectively. Defining thresholds for such effects is challenging, especially for wholly aquatic taxa. Destruction of critical habitat (e.g. prey reduction and ocean noise) threatens the survival and recovery of the 75 members of the endangered southern resident killer whale population found in transboundary (Canada–United States) Pacific waters. The population's dynamics are now driven largely by the cumulative effects of prey limitation (e.g. the endangered Chinook salmon), anthropogenic noise and disturbance (e.g. reducing prey accessibility), and toxic contaminants, which are all forms of habitat degradation. It is difficult to define a single threshold beyond which habitat degradation becomes destruction, but multiple lines of evidence suggest that line may have been crossed already. [ABSTRACT FROM AUTHOR]

Habitat loss and degradation have led to the extinction of many species worldwide. The endangered Blanding's Turtle (Emydoidea blandingii (Holbrook, 1838)), a semi-aquatic freshwater turtle, occupies a wide range of wetlands and landscapes primarily in southeastern Canada and the Great Lakes region of the United States. We explored whether the probability of wetland occupancy by Blanding's Turtles is affected by the surrounding landscape. We used visual surveys, environmental DNA, and Atlas data to document the presence of Blanding's Turtles in wetlands in Ottawa, Ontario, Canada. We tabulated landscape composition at multiple scales surrounding the wetlands to determine whether landscape composition can predict wetland occupancy. Generally, wetlands surrounded by forest and other undisturbed lands were most likely to harbour Blanding's Turtles, whereas those surrounded by more human-disturbed lands were least likely to harbour Blanding's Turtles. Larger wetlands and a high proportion of wetlands in the surrounding landscape also increased the probability of occupancy by Blanding's Turtles. Finally, older wetlands were more likely to be occupied by Blanding's Turtles. The ability to estimate a species' probability of occupancy can aid in conservation efforts, such as critical habitat delineation. [ABSTRACT FROM AUTHOR]

Shifts in species ranges and viability introduced by climate change are creating difficult challenges for scientists and citizens. In many cases, the seriousness of threats to endangered species is forcing policy makers and resource managers to consider novel species protection strategies, either to complement or replace existing conservation approaches. This paper seeks to deepen understanding of public views on a range of conventional and novel management initiatives designed to protect species under the threat of extinction, based on results from an online survey conducted in the USA and Canada. Participants first selected a preferred intervention strategy and were then presented with a series of scenarios, focused on protection of the endangered bristlecone pine, which allowed them to explore their willingness to shift to a new policy regime with a better chance of protecting the species. The use of a decision-pathways survey design allowed us to examine the strength of the nudge required to elicit a shift in their position and the reasoning underlying selection of a preferred management alternative. Results generally support the conclusion that, so long as a clear rationale is provided, there exists surprisingly widespread support for the adoption of novel management approaches to save threatened or endangered species even if this requires more intensive genetic and transformational interventions that are costly or ethically challenging. [ABSTRACT FROM AUTHOR]

Extinction rates are expected to increase during the Anthropocene. Current extinction rates of plants and many animals remain unknown. We quantified extinctions among the vascular flora of the continental United States and Canada since European settlement. We compiled data on apparently extinct species by querying plant conservation databases, searching the literature, and vetting the resulting list with botanical experts. Because taxonomic opinion varies widely, we developed an index of taxonomic uncertainty (ITU). The ITU ranges from A to F, with A indicating unanimous taxonomic recognition and F indicating taxonomic recognition by only a single author. The ITU allowed us to rigorously evaluate extinction rates. Our data suggest that 51 species and 14 infraspecific taxa, representing 33 families and 49 genera of vascular plants, have become extinct in our study area since European settlement. Seven of these taxa exist in cultivation but are extinct in the wild. Most extinctions occurred in the west, but this outcome may reflect the timing of botanical exploration relative to settlement. Sixty‐four percent of extinct plants were single‐site endemics, and many occurred outside recognized biodiversity hotspots. Given the paucity of plant surveys in many areas, particularly prior to European settlement, the actual extinction rate of vascular plants is undoubtedly much higher than indicated here. Article impact statement: The number of presumed extinct plants from the continental United States and Canada is much greater than previously recognized. [ABSTRACT FROM AUTHOR]

The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) has assessed the Lake Sturgeon (Acipenser fulvescens) across 4 designatable units (DU) as Endangered in DUs 1 and 2, Threatened in DU 4 and Special Concern in DU 3. Here population modelling, using a female only matrix model, is presented to determine population-based recovery targets, assess the impact of anthropogenic harm, and conduct long-term projections of population recovery in support of a recovery potential assessment (RPA) for Lake Sturgeon populations in Canada. Simulations were conducted for populations with 5 distinct growth patterns characterized by their rate of growth and maximum size to incorporate the diversity in life-history characteristics expected across Canada. Populations with slower growth were estimated to have greater adult survival rates (~ 95%) and resultantly greater generation times (> 50 years) relative to faster growth sturgeon populations (~ 92% and ~ 30 years). Patterns in elasticity estimates were similar across growth types. Under most scenarios population growth rate (λ) was most sensitive to changes to survival of young adults (age 26-62). The exception to this was populations experiencing continued reduced adult survival (leading to population decline); which were most sensitive to changes to the survival rate of older juveniles (age 13-25). This indicates the importance of understanding the current stresses and the age distribution of a population when considering harm or determining what recovery actions to take. To achieve demographic sustainability, (i.e., a self-sustaining population over the long term) under conditions with a catastrophe probability of 0.15/generation and a quasi-extinction threshold of 25 adult females at a 1% probability of extinction over 250 years, population sizes ranging from 1,255-4,840 adult females were required. Populations with faster growth required larger population sizes (~ 5,000) to achieve demographic sustainability as their lower generation times resulted in increased frequency of catastrophic population decline (a 50% decline every 200-250 years compared to 340-360 years for slow growth Lake Sturgeon). MVP population size required between 550->13,000 ha of lake habitat and 162-3,800 ha of river habitat (inclusive of both sexes and all age classes). Recovery times are variable, dependent on initial population size and the rate of population growth. [ABSTRACT FROM AUTHOR]

In Genesis 2, Adam was given the task of naming the animals. Naming is a relational activity that promotes stewardship - we protect what we name. The naming of food products derived from these creatures is more complex, entailing both the common and scientific names of the species as well as cultural, commercial, and legal naming practices. This complexity of naming can result in the mislabeling of foods: "what you bought" is not "what you got." Fish are particularly prone to mislabeling, not least because North Americans are typically unconcerned with fish biodiversity, and those features that permit species identification are often removed during processing. The recent collapse of many fish stocks has given correct naming of the fishes a new urgency. A dataset generated by students taking a Principles of Genetics class at faith-based Ambrose University in Calgary, Alberta, demonstrates that mislabeling rates can be high-from 20% to 35% offish products from a dataset of nearly three hundred were mislabeled. However, there is more to naming than mislabeling. Legally permissible names excluded culturally significant sources of cuisine, conflating the mislabeling problem and distracting from the true sources of mislabeling. Legally ambiguous labeling, in which one market name is legally applied to several species, appeared to facilitate mislabeling and hid the sale of species at risk of extinction, hinting at how both consumers and regulators could reduce the impact on endangered species. Naming is a type of knowledge; we need to develop a greater knowledge of the fish we are eating in order to better fulfill God's blessing to the fishes. [ABSTRACT FROM AUTHOR]

Declines in Arctic sea ice associated with climate change have resulted in habitat loss for ice-adapted species, while facilitating increased human development at higher latitudes. Development increases land-use and shipping traffic, which can threaten ecologically and culturally important species. Female polar bears (Ursus maritimus) and cubs are susceptible to disturbance during denning; a better understanding of denning habitat distribution may aid management. We compiled existing location data on polar bear denning (n = 64 sources) in Canada between 1967 and 2018, including traditional ecological knowledge (TEK) studies, government and consultant reports, peer-reviewed scientific articles, and unpublished data acquired through data-sharing agreements. We synthesized these data to create a map of known denning locations. Most coastal regions in northern Canada supported denning, but large areas exist where denning is unreported. Gaps remain in the knowledge of polar bear denning in Canada and filling these will aid the conservation and management of polar bears in a changing Arctic. [ABSTRACT FROM AUTHOR]

Biodiversity loss has accelerated over the past century and freshwater species overall are among those experiencing greatest declines. Genetic resources have the potential to help evaluate the full magnitude of this loss and represent a key tool to effectively allocate conservation resources and monitor the success of restoration efforts. The full power of genetic resources will be realized when the daunting task of referencing all DNA sequences of freshwater organisms is complete. Here, we quantified the availability and distribution of barcode and genome data for freshwater macroscopic organisms in Canada, a country rich in inland water resources and thus particularly vulnerable to aquatic species losses. Impressively, most inland water species (86 %) were represented by barcodes recorded in the BOLD Systems database, while very few had full genomes available (<4 %) in the NCBI database. We identified barcode data deficiencies in northern regions and for taxa assessed as most at risk or without sufficient information for conservation status classification. As expected, the speciose insect group had a lower-than-average number of records per species and a high proportion of data deficient species without adequate barcode coverage. This study highlights where future sequencing resources should be prioritized within initiatives such as the Canada BioGenome Project and BIOSCAN Canada and provides a workflow that could be applied internationally to inform conservation management plans and to mitigate biodiversity loss. • Paucity of monitoring data limits conservation status assessment of freshwater taxa. • We compiled barcodes and genomes for Canadian inland water-reliant macroorganisms. • 86 % of species had barcodes, however data deficiencies spanned all domains of life. • Insects and species at risk have been under-sampled, especially in Northern regions. • We provide a list of taxa to prioritize future sequencing efforts on. [ABSTRACT FROM AUTHOR]

Multiple natural and anthropogenic stressors pose a serious threat to the health and diversity of biological communities. A growing body of research suggests that one consequence of these stressors has been a regional-scale loss of crayfish populations across south-central Ontario. The mechanisms contributing to the imperilment of crayfish probably include historical acidification and metal contamination, shoreline development and habitat loss, increased water temperature, declining [Ca] in lake water, and invasion by nonnative species (i.e., Smallmouth Bass and the rusty crayfish). Long-term monitoring data of crayfish populations in Algonquin Provincial Park (Ontario) have documented marked declines in Cambarus bartonii abundance despite the relatively isolated nature of the study lakes. Furthermore, monitoring data indicate that the onset of this decline may predate the monitoring record, thereby creating a need for the use of paleolimnological techniques to infer past conditions. We used a multiple proxy approach (i.e., diatoms and cladocerans) to reconstruct key environmental variables (e.g., pH) and long-term changes in lake chemistry (e.g., [Ca]) as they pertain to crayfish population loss. We found that interactions between pH and [Ca] have led to the decline in crayfish abundance and to the continued lack of recovery of these populations. Furthermore, lake-water [Ca] in all 4 Algonquin Park lakes are now <2.0 mg/L, the lowest hypothesized requirement for freshwater crayfish (2–10 mg/L), suggesting that short-term recovery of crayfish populations is unlikely, despite pH recovery. [ABSTRACT FROM AUTHOR]

Habitat change is a major driver of species distribution and persistence, but there have been few recorded extinction events for terrestrial mammals across Canada. Currently, we are observing the decline, extirpation, and perhaps extinction of several evolutionarily significant units of woodland caribou ( Rangifer tarandus caribou ), an iconic and cultural keystone species. We used an extensive set of caribou locations (5 subpopulations, 102 animals, 270,808 GPS-collar locations) collected over 11 years within the Central Mountain Designatable Unit to develop species distribution models that quantified avoidance by caribou of anthropogenic and natural disturbance features. Those empirical relationships allowed us to measure the loss of habitat over a 22-year period and correlate habitat change with measured population decline. The disturbance responses for caribou were complex and varied by season and subpopulation. We modelled a zone of influence for roads (1.75 km), seismic and pipelines (2.5 km), oil and gas features (4.25 km), cutblocks (5.5 km), burns (8.0 km), and coal mines (3.0 km). When the distribution models for each subpopulation were applied to the respective seasonal ranges, we measured a maximum loss in high-quality habitat of 65.9%. The reduction in habitat was strongly correlated with the annual multiplicative growth rate of 5 subpopulations of caribou. At current rates of habitat loss and population decline, these caribou, a significant component of Canada’s biodiversity, are unlikely to persist. Although the factors leading to extinction are complex, the cumulative impacts of industrial development are a correlative if not causative factor. [ABSTRACT FROM AUTHOR]

Protecting and promoting recovery of species at risk of extinction is a critical component of biodiversity conservation. In Canada, the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) determines whether species are at risk of extinction or extirpation, and has conducted these assessments since 1977. We examined trends in COSEWIC assessments to identify whether at-risk species that have been assessed more than once tended to improve, remain constant, or deteriorate in status, as a way of assessing the effectiveness of biodiversity conservation in Canada. Of 369 species that met our criteria for examination, 115 deteriorated, 202 remained unchanged, and 52 improved in status. Only 20 species (5.4%) improved to the point where they were ‘not at risk’, and five of those were due to increased sampling efforts rather than an increase in population size. Species outcomes were also dependent on the severity of their initial assessment; for example, 47% of species that were initially listed as special concern deteriorated between assessments. After receiving an at-risk assessment by COSEWIC, a species is considered for listing under the federal Species at Risk Act (SARA), which is the primary national tool that mandates protection for at-risk species. We examined whether SARA-listing was associated with improved COSEWIC assessment outcomes relative to unlisted species. Of 305 species that had multiple assessments and were SARA-listed, 221 were listed at a level that required identification and protection of critical habitat; however, critical habitat was fully identified for only 56 of these species. We suggest that the Canadian government should formally identify and protect critical habitat, as is required by existing legislation. In addition, our finding that at-risk species in Canada rarely recover leads us to recommend that every effort be made to actively prevent species from becoming at-risk in the first place. [ABSTRACT FROM AUTHOR]

Studies of biodiversity dynamics have been cast on either long (systematics) or short (ecology) time scales, leaving a gap in coverage for moderate time scales of decades to centuries. Large-scale biodiversity information resources now available offer opportunities to fill this gap for many parts of the world via detailed, quantitative comparisons of assemblage composition, particularly for regions without rich time series datasets. We explore the possibility that such changes in avifaunas across the United States and Canada before and after the first three decades of marked global change (i.e., prior to 1980 versus after 2010) can be reconstructed and characterized from existing primary biodiversity data. As an illustration of the potential of this methodology for sites even in regions not as well sampled as the United States and Canada, we also explored changes at a single site in Mexico (Chichén-Itzá). We analyzed two large-scale datasets: one summarizing bird records in the United States and Canada before 1980, and one for the same region after 2010. We used probabilistic inventory completeness analyses to identify sites that have avifaunas that have likely been inventoried more or less completely. We prepared detailed comparisons between the two time periods to analyze species showing distributional changes over the time period analyzed. We identified 139 sites on a 0.05° grid that were demonstrably well-inventoried before 1980 in the United States and Canada, of which 108 were also well-inventoried after 2010. Comparing presence/absence patterns between the two time periods for 601 bird species, we found significant spatial autocorrelation in overall avifaunal turnover (species gained and lost), but not in numbers of species lost. We noted potential northward retractions of ranges of several species with high-latitude (boreal) distributions, while other species showed dominant patterns of population loss, either rangewide (e.g., Tympanuchus cupido) or regionally (e.g., Thryomanes bewickii). We developed linear models to explore a suite of potential drivers of species loss at relatively fine-grained resolutions (<6 ​km), finding significant effects of precipitation increase, particularly on the eastern border of the United States and Canada. Our exploration of biotic change in Chichén-Itzá included 265 species and showed intriguing losses from the local avifauna (e.g., Patagioenas speciosa), as well as vagrant and recent invasive species in the Yucatán Peninsula. The present work documents both the potential for and the problems involved in an approach integrating primary biodiversity data across time periods. This method potentially allows researchers to assess intermediate-time-scale biodiversity dynamics that can reveal patterns of change in biodiversity-rich regions that lack extensive time-series information. [ABSTRACT FROM AUTHOR]

We conducted 3,050 point counts from 2005-2009 (May-Jul) in 82 wetlands in three Canadian provinces (Ontario, Québec, and Manitoba) to quantify colonization and extinction dynamics of Least Bittern (Ixobrychus exilis) populations to detect geographic variations across provinces and to analyze effects of weather conditions, date, and survey methodology that may affect detection probability of Least Bitterns. Least Bitterns were detected at 773 (25%) of the 3,050 point counts with birds detected in 25, 26, and 28% of all point counts in Ontario, Quebec, and Manitoba, respectively. Occupancy probability in the first year of the study was lower in Quebec sites (0.26) compared to Manitoba sites (0.53). However, Quebec sites had higher probabilities of colonization (0.67) than Ontario (0.32) and Manitoba (0.27). Probabilities of extinction did not differ across provinces but varied across years. Detection probability did not vary with weather variables (cloud cover, wind speed, air temperature - linear or quadratic effect) but decreased from mid-May (0.19) to mid-July (0.09). Detection probability was lower (0.13) for the first passive listening period than the call-broadcast period (0.28) and the second passive listening period (0.33). Observed differences in extinction and colonization probability between provinces and years show that occupancy dynamics vary both temporally and geographically, stressing the need to continue long-term monitoring of Least Bittern populations across the breeding range to detect geographic variation and changes in occupancy. We recommend Least Bittern surveys begin in mid-May at higher latitudes and use a second passive listening period following the call-broadcast period to increase detection of the species. [ABSTRACT FROM AUTHOR]

Abundance indices of southern Gulf Leucoraja ocellata residing in Northumberland Strait, Canada, declined from 2001 to 2005, but increased during 2006 to 2008. Catch rates in 2009 were the lowest in the time series. The size of the area occupied in Northumberland Strait varied with changes in the abundance indices. Leucoraja ocellata were primarily caught in the north-west half of the strait over sandy to gravelly seabed; a near total absence was documented from the eastern half despite suitable habitat and a previously established presence documented during research surveys conducted before 2000. In Northumberland Strait, L. ocellata occupied shallow (50% cumulative occurrence = 12 m) and warm (50% cumulative occurrence = 16·5° C) coastal waters and were not present in the cold (<1° C, >35 m) intermediate layer. Abundance and distribution data highlight the need for continuing studies to monitor the status of this population, which is classified as endangered by the IUCN and Committee on the Status of Endangered Wildlife in Canada. [ABSTRACT FROM AUTHOR]

A sedimentary record from the Buchanan Lake section, Canadian High Arctic, shows anomalous high levels of mercury (Hg) during the latest Permian extinction (LPE) on northwest Pangea. Significant influx of Hg progressively overwhelmed the marine system. Major disruption of the organic matter-mediated Hg drawdown process resulted in accumulation of dissolved Hg to maximum levels at the LPE boundary, affecting an already stressed global ecosystem. A switch to euxinic marine conditions at the LPE boundary led to chemical drawdown of Hg sulfides, as marked by progressive Hg mitigation. This allowed self-recovery from toxic Hg conditions, and ultimately led to reestablishment of the internal Hg-organic matter drawdown process. We hypothesize that anomalous Hg levels may be attributed to the significant natural atmospheric emissions caused by catastrophic Siberian Traps volcanic eruptions. [ABSTRACT FROM AUTHOR]

Boreal caribou were extirpated from the Charlevoix region (Québec) in the 1920s because of hunting and poaching. In 1965, the Québec government initiated a caribou reintroduction program in Charlevoix. During the winters of 1966 and 1967, a total of 48 boreal caribou were captured, translocated by plane, and released within enclosures; only their offspring (82 individuals) were released in the wild. Between 1967 and 1980, a wolf control program was applied to support caribou population growth. The caribou population, however, remained relatively stable at 45-55 individuals during this period. During the 1980s, the population grew slowly at a rate of approximately 5% each year to reach a peak of 126 individuals in 1992. At that time, Bergerud & Mercer (1989) reported that the Charlevoix experiment was the only successful attempt at caribou reintroduction in the presence of predators (in North America). Afterwards, the population declined and since then it has been relatively stable at about 80 individuals. Here we reviewed the literature regarding the ecology and population dynamics of the Charlevoix caribou herd since its reintroduction, in an attempt to critically assess the value of reintroduction as a conservation tool for this species. Indeed, the Charlevoix caribou herd is now considered at very high risk of extinction mostly because of its small size, its isolation from other caribou populations, and low recruitment. The Charlevoix region has been heavily impacted by forestry activities since the early 1980s. Recent studies have indicated that these habitat modifications may have benefited populations of wolves and black bears--two predators of caribou--and that caribou range fidelity may have exposed caribou to higher predation risk via maladaptive habitat selection. As females are ageing, and females and calves suffer high predation pressure from wolves and bears respectively, we suggest that the future of this reintroduced herd is in question and that they are facing a high probability of extinction in the near future if further action is not taken. [ABSTRACT FROM AUTHOR]

The reported decline of the Bathurst herd has caused considerable concern and has raised rumours of a "crisis" in which there is a possibility of extinction. This paper reflects on relevant lessons learned from the officially declared "crisis" of population decline in 1955/56 and a second crisis of overpopulation identified by the author a decade later. [ABSTRACT FROM AUTHOR]

Species status assessments are often hindered by a paucity of demographic, abundance, or distributional data. Although extinction-risk correlates have been identified, their wide applicability may be compromised by differences in the variables examined, modeling technique, and phylogenetic or distributional scale. Here, we apply a common analytical approach to examine 14 possible extinction-risk correlates for mammals, fishes, and birds throughout Canada. Among mammals, risk is positively and strongly correlated with road density and age at maturity for land animals and weakly with body size for sea dwellers. Delayed maturity is of primary importance to predicting risk status in fishes, with small body size of secondary importance in freshwater environments. For birds, road density is the dominant correlate of risk. Logistic regression in a multimodel framework offers an instructive means of identifying risk correlates and of applying them in a practicable, empirically defensible manner, thus enhancing support for species-independent risk criteria. [ABSTRACT FROM AUTHOR]

Abstract: This study investigates differences in the δ13Ccol, δ15N, δ13Csc, δ18Osc, Sr/Ca, and Ba/Ca values of juvenile and adult woolly mammoths (Mammuthus primigenius) from Old Crow, Yukon, Canada. The data indicate that nursing in woolly mammoths lasted at least three years, and was associated with minimal decreases in δ13Ccol (~0.2‰), large decreases in δ13Csc (~1.5‰), and large increases in δ15N (~2‰) and δ18Osc (~2‰) values. Sr/Ca and Ba/Ca ratios suggest that woolly mammoth juveniles began consuming plant foods between 2 and 3 “African Elephant Years” of age, much later than the initiation of weaning in modern elephants. We hypothesize that delayed weaning was an adaptation to increased predation risk and decreased food quality/quantity during the extended hours of darkness that occur in winter at high latitudes. Prolonged nursing and delayed weaning may have made mammoths particularly vulnerable to climatic stressors or human hunting. [ABSTRACT FROM AUTHOR]

The article discusses climate change and the peripheral populations' conservation in Canada. It notes the debate that has sparked over the inclusion of peripheral populations in the national species conservation and the three population-level responses such as range migration, adaptation, and extirpation. It indicates that the range of species maybe squeezed if the leading edge of peripheral populations is threatened by other anthropogenic pressures. It proposes that better understanding of the dynamic processes of conservation biology and the practice of conservation is important in conserving the at-risk species in the country.

Aim Anthropogenic habitat loss is usually cited as the most important cause of recent species’ extinctions. We ask whether species losses are in fact more closely related to habitat loss than to any other aspect of human activity such as use of agricultural pesticides, or human population density (which reflects urbanization). Location Canada. Methods We statistically compared areas in Canada where imperiled species currently occur, versus areas where they have been lost. Using multiple regressions, we relate the numbers of species that had suffered range reductions in an ecoregion to variables that represent present habitat loss, pesticide use and human population density. Results We find high losses of imperiled species in regions with high proportions of agricultural land cover. However, losses of imperiled species are significantly more strongly related to the proportion of the region treated with agricultural pesticides. The relationship between species losses and area treated with pesticides remains significant after controlling for area in agriculture. Main conclusions Our results are consistent with the hypothesis that agricultural pesticide use, or something strongly collinear with it (perhaps intensive agriculture more generally), has contributed significantly to the decline of imperiled species in Canada. Habitat conversion per se may be a less important cause of species declines than how that converted habitat is used. [ABSTRACT FROM AUTHOR]

Changes in the composition of local communities through time (i.e. species turnover) is a common phenomenon in insular biology. However, the mechanisms promoting variation in species turnover, both among islands and among species, are poorly understood. In an effort to better understand the causes of variation in species turnover, we evaluated the colonization and extinction dynamics of plant populations on 18 small islands off the west coast of Canada. In 1997, we quantified total population sizes of 10 woody angiosperm species. A decade later, we resampled islands to test whether: 1) species turnover occurred, 2) colonization events were offset by extinction events, 2) variation in extinction rates among islands was associated with population sizes, average plant heights, island area, island isolation or each island's exposure to ocean-born disturbances, and 3) variation in extinction rates among species was associated with plant life history traits. Results showed that extinction events outnumbered colonization events, suggesting that the metacommunity is in ‘disequilibrium’. Variation in extinction rates among islands was unrelated to island area and isolation. However, extinction rates increased with exposure to ocean-born disturbances and decreased with both initial population sizes and average plant heights. Species with thicker, tougher leaves (i.e. high leaf mass per area) were less prone to extinction than species with thinner, more papery leaves. Overall results indicate that species turnover is common and that it is generated primarily by extinction. Variation in extinction rates appears to result from an interaction between among-island effects (exposure, population size and plant stature) and among-species effects (leaf toughness), suggesting that ocean-born disturbances play a key role in determining metacommunity structure. [ABSTRACT FROM AUTHOR]

Background: Categories of imperilment like the global IUCN Red List have been transformed to probabilities of extinction and used to rank species by the amount of imperiled evolutionary history they represent (e.g. by the Edge of Existence programme). We investigate the stability of such lists when ranks are converted to probabilities of extinction under different scenarios. Methodology and Principal Findings: Using a simple example and computer simulation, we show that preserving the categories when converting such list designations to probabilities of extinction does not guarantee the stability of the resulting lists. Significance: Care must be taken when choosing a suitable transformation, especially if conservation dollars are allocated to species in a ranked fashion. We advocate routine sensitivity analyses. [ABSTRACT FROM AUTHOR]

1. We surveyed 62 Canadian Shield lakes (<50 ha) to determine the relationship between factors related to isolation and extinction and the occurrence of brook trout (BT) ( Salvelinus fontinalis), for which local extinctions have been documented over the last century in half of the lakes. 2. Logistic regression and information–theoretic model selection were used to determine the importance for the occupancy of BT of (i) isolation factors (degree of lake connectivity and the proximity of source populations of BT in neighbouring bodies of water) and (ii) extinction factors (lake morphometry and trophic status, as proxies of the risk of lake anoxia; predation and competition; and flooding caused by beaver ( Castor canadensis) dams, which could potentially increase the risk of anoxia). 3. Isolation factors were the best predictors of the absence of BT in these lakes. Among extinction factors, only the impact of beaver dams (as measured by an index of increased water level and mortality of shrubs and trees in the littoral zone) improved model fits. Beaver dams were present at the outlets of all study lakes, but extensive mortality of riparian trees and shrubs was more common in lakes where BT populations were extinct. 4. Taken together, these results suggest that recolonization is a major factor determining the occurrence of BT while flooding caused by beaver dams might contribute to BT extinction by increasing the likelihood of winterkill in these small lakes. [ABSTRACT FROM AUTHOR]

Spatial distribution, patchy environments, and population turnover have many fundamental implications for conservation ecology. Common eider (Somateria mollissima L., 1758) population processes were investigated in Labrador, Canada, between 1998 and 2003. We predicted that local colonies would exhibit population turnover, that extinction would be negatively related to colony and patch size, that colonization would be negatively related to island isolation, and that intraspecific incidence–abundance relationships would be positive. We found that small colonies were prone to extinction, but patch size was not a significant predictor of extinction, nor was colonization related to isolation. The overall observed annual extinction and colonization rates were 0.11 ± 0.02 and 0.41 ± 0.06, respectively, and showed variation across archipelagos. At two spatial scales we found that mean colony size was a positive predictor of island occupancy (incidence), and these relationships were maintained across years. Our findings show that common eider colonies in Labrador are dynamic and have greater turnover rates than previously expected in a species that is considered highly philopatric. Our findings support the notion that highly mobile organisms such as migratory birds can exhibit characteristics associated with metapopulation processes. [ABSTRACT FROM AUTHOR]

Farmed salmon strains have been selected to improve growth rates as well as other traits of commercial interest but the 2 million farmed salmon escaping annually may enhance the risk of extinction of wild populations through genetic and ecological interactions. Here, we compare the transcription profiles of 3557 genes in the progeny of farmed and wild Atlantic salmon from Norway and Canada grown in controlled conditions, and demonstrate that five to seven generations of artificial selection led to heritable changes in gene transcription profiles, the average magnitude of the differences being 25% and 18% for at least 1.4% and 1.7% of the expressed genes in juvenile salmon from Norway and Canada, respectively. Moreover, genes showing significant transcription profile differences in both farmed strains (16%) all exhibited parallel changes. These findings, along with the identification of several genes whose expression profiles were modified through artificial selection, provide new insights into the molecular basis of parallel evolution, and suggest how gene flow from farmed escapees may affect the genetic integrity of wild populations. [ABSTRACT FROM AUTHOR]

Species status assessment and the conservation of biological diversity may require defining units below the species level to portray probabilities of extinction accurately and to help set priorities for conservation efforts. What those units should be has been debated in the scientific literature largely in terms of evolutionarily significant units (ESUs), but this discourse has had little impact on government policy with regard to status assessment. As with species concepts, the variously proposed ESU concepts have not been resolvable into a single approach. The need for a practicable procedure to identify infraspecific entities for status assignment is the motivation behind employing designatable units (DUs). In aid of a policy to prevent elements of biodiversity from becoming extinct or extirpated, DUs are determined during the process of resolving a species' conservation status according to broadly applicable guidelines. The procedure asks whether putative DUs are distinguishable based on a reliably established taxonomy or a well-corroborated phylogeny, compelling evidence of genetic distinction, range disjunction, and/or biogeographic distinction as long as extinction probabilities also differ. The language of the DU approach avoids wording that implies value judgments concerning evolutionary importance or significance. Because species conservation status assessment is not science but, rather, the use of science to further policy, DUs contribute to a precautionary approach to listing whereby status may be assessed even though knowledge of systematic relationships below the species level may be lacking or unresolved. The pragmatic approach of using DUs has been adopted by the Committee on the Status of Endangered Wildlife in Canada for status assessment of species under the Canadian Species at Risk Act. [ABSTRACT FROM AUTHOR]

Canada is one of the last places on earth with extensive wilderness areas, yet the number of Canadian species threatened with extinction continues to rise every year. Using satellite-derived land use data, we find that habitat loss explains most of the variation in numbers of endangered species across Canada. Habitat loss within species ranges is, therefore, likely to be the leading factor inhibiting their recovery. We measured habitat loss individually within the known ranges of 243 terrestrial species at risk of extinction across Canada. Recovery potential, as measured by extent of natural habitat within each species’ range, is bimodally distributed, but less than 50% of the range of the majority of Canada's species at risk is natural habitat and there is no detectable habitat remaining for 16 of the 243 species at risk. There were no differences in the recovery potential of species categorized either by threat level (special concern, threatened, or endangered) or taxon. Despite having extensive wilderness areas, Canada has similar rates of endangerment to other countries in the Americas, underlining the effect of severe habitat loss to intensive agriculture that has occurred in Canada's most biologically diverse regions. Improvements to protected areas networks and especially cooperative conservation activities with private landowners will do the most to improve the recovery prospects of species at risk in Canada. [ABSTRACT FROM AUTHOR]

Microbial precipitation of calcium carbonate has played a vital role in the development of carbonate platforms since their initiation in the Proterozoic. We report here the varied roles that microbial carbonates played in Late Devonian carbonate platforms in the Alberta basin, Canada. We recognize microbial carbonates as important contributors within the carbonate system during times of major environmental change including transgressive events in platform environments and the recovery interval following the Frasnian–Famennian mass extinction. Detailed sequence stratigraphic analysis of two isolated platforms in the Canadian Rockies was used to document their evolution from a regional ramp to isolated platforms with phases of progradation, aggradation and backstepping, and renewed progradation related to rates of second-order and third-order sea-level change and basin infill. The carbonate system was reorganized following annihilation of many carbonate-producing biota during the Frasnian–Famennian mass extinction. Microbial carbonates figure prominently in both Frasnian platform development and the Famennian recovery of the carbonate system following the Frasnian–Famennian mass extinction. During transgressive platform phases deeper-water facies with a crinoid, rugose coral, and microbe dominated biota abruptly overlie prograding stromatoporoid framestones. Microbial carbonates consist of abundant Girvinellid oncoids that nucleated around other fossil clasts. The temporary replacement of stromatoporoid communities during transgression implies a shift from oligotrophic to mesotrophic conditions and the microbes likely capitalized on the change in nutrient supply. Microbes played a significant role in highstand reef margin facies where Renalcis was a binder and cementer in stromatoporoid framestones and downslope rugose coral/stromatoporoid mounds. Microbially laminated carbonates also form stromatolitic mats in peritidal shallowing-upward cycles and repetitive stromatolitic intervals commonly indicate sea-level lowstands associated with the development of sequence boundaries. Stromatoporoid reefs and their associated reef interior facies indicate an oligotrophic ecosystem where microbial carbonates were relegated mainly to cryptic or stressed marine habitats. An end-Frasnian sea-level lowstand exposed the isolated carbonate platforms. Transgression and mass extinction characterize the Frasnian–Famennian boundary event and microbial carbonates occur at this horizon in western Canada. Stromatolites, oncoids, and large-scale microbial thrombolites appear to be opportunistic taxa temporarily filling unoccupied ecological niches immediately above the extinction boundary. The paucity of megafauna implies that few metazoans remained to exploit available food and nutrient sources and the stratigraphic position of these microbial carbonates supports their interpretation as ‘disaster forms’. Microbial carbonates thus play several significant roles in the development of Late Devonian carbonate systems in western Canada. Microbial carbonates occur at important sequence stratigraphic and paleoecologic horizons indicating changes in sea level, nutrient supply, and biotic assemblages. These examples indicate that microbial carbonates can be important indicators of environmental and ecological change within carbonate systems. [Copyright &y& Elsevier]

Studies the home ranges and seasonal movements of 20 wood turtles Clemmys insculpta living near the northern limit of their distribution in Mauricie, Quebec. The wood turtle is irregularly distributed in northeastern North America. Wood turtles seem to demonstrate great fidelity in the use of their home range. Illegal collecting, habitat destruction, fragmentation, and recreational activities are the greatest causes of wood turtle decline and disappearance. It is hypothesized that home ranges would be larger in the northern population than in more southerly ones, since home range will increase with increasing latitude.

With global biodiversity declines, government regulations protecting wildlife serve a key role in species persistence. Despite its importance, planning for protection can be a slow process, taking up to several decades. Such delays have led to species declines and extinction. Here, we investigate the factors driving time between conservation listing and the creation of a plan to support species recovery. Using Canada's Species at Risk Act as a case study, we used Cox proportional-hazards models to test how quickly a species designatable unit (DU) would receive a recovery plan given the reasons for its designation, conservation status, taxon, sociopolitical climate, the extent of scientific research, and public awareness. AIC model selection revealed that sociopolitical factors best explained how quickly a DU would receive a plan. We found that the time for a DU to receive a plan decreased the more often a majority government was in power, the fewer environmental bills passed, and the lower average GDP growth rate during planning. Our results highlight the need for greater consistency in species recovery planning based on conservation needs and status, regardless of sociopolitical climate. We recommend further examination of the relationship between time for recovery planning and plan effectiveness to elucidate how planning delays impact species recovery. [Display omitted] • Delays in conservation planning are common but detrimental to species persistence. • We examined if recovery planning is guided by conservation needs or other biases. • Planning timelines were best explained by sociopolitical factors. • Jurisdictional presence and majority governments speed up planning timelines. • Environmental legislation and GDP growth slow down planning timelines. [ABSTRACT FROM AUTHOR]

A major need in migratory game bird management in North America has been improved data on the annual harvest. Two large-scale surveys are being annually conducted in the United States and Canada as part of the monitoring program to assist management in the use of shooting regulations, since loss to hunting is an important factor affecting such populations. The main objectives of the harvest survey are to provide at both the provincial and national levels reliable estimates of the following characteristics of the annual harvest in an attempt to preserve breeding populations and permit a reasonable annual harvest. The surveys are also intended to provide estimates of change in activity and kill between seasons and provinces with accuracy adequate for purposes of waterfowl management. Another important objective of the surveys is to provide information needed for research on various problems, such as effects of changes in shooting regulations on waterfowl hunting activity and harvest. Estimates of kill and activity in Canadian mail surveys of migratory game birds have been subject to considerable survey errors. This article reviews the design of the surveys and describes the studies undertaken to estimate and correct for these errors.

• Continent-wide study on effects of agriculture in forest and prairie ecosystems. • Greater biodiversity loss with higher contrast of agricultural and natural land cover. • Functionally redundant species lost first as agriculture expands. • Numerical compensation following species loss in both ecosystems. The impact of agriculture on biodiversity depends on the extent and types of agriculture and the degree to which agricultural land contrasts with the natural ecosystem. Most research on the latter comes from studies on the influence of different agricultural types within a single ecosystem with far less study on how the natural ecosystem context shapes the response of biodiversity to agricultural production. We used citizen science data from agricultural areas in Canada's Eastern Hardwood-Boreal (forest ecosystem, n=108 landscapes) and Prairie Pothole (prairie ecosystem, n=99) regions to examine how ecosystem context shapes the response of avian species diversity, functional diversity and abundance to the amount of arable crop and pastoral agriculture at landscape scales. Avian surveys were conducted along 8km transects of Breeding Bird Survey routes with land cover assembled within a 20km2 landscape around each transect. The amount of agriculture at which species diversity peaked differed between the forest (15%) and prairie (51%) ecosystems, indicating that fewer species tolerated the expansion of agriculture in the former. In both ecosystems, functional diversity initially increased with agriculture and peaked at higher amounts (forest: 42%, prairie: 77%) than species diversity suggesting that functional redundancy was lost first as agriculture increased. Species turnover with increasing agriculture was primarily among functional groups in forest where a shift from a low to a high agriculture landscape led to a decline in the percent of the community represented by Neotropical migrants, insectivores, upper foliage gleaners and bark foragers, and an increase in the percent of the community represented by short-distance migrants, granivores, omnivores and ground gleaners. There were few distinct shifts in the percent of the community represented by different functional groups in the prairie ecosystem. Total abundance was the least sensitive measure examined in both ecosystems and indicated that species losses with agriculture are likely followed by numerical compensation from agriculture tolerant species. Our results highlight the importance of ecosystem context for understanding how biodiversity is affected by agricultural production with declines in diversity occurring at lower agricultural extents in ecosystems with lower similarity between natural and agricultural land covers. These findings allow for more specific conservation recommendations including managing for species intolerant to agriculture in prairie ecosystems and limiting the expansion of high contrast agriculture and the loss of semi-natural habitat, such as hedge rows, in historically forested ecosystems. [ABSTRACT FROM AUTHOR]