Naujokaitis-Lewis I.R.,University of Toronto |
Curtis J.M.R.,Canadian Department of Fisheries and Oceans |
Tischendorf L.,Consulting Inc. |
Badzinski D.,Bird Studies Canada |
And 2 more authors.
Diversity and Distributions | Year: 2013
Aim: Species distribution models (SDMs) coupled with metapopulation dynamics models can integrate multiple threats and population-level processes that influence species distributions. However, multiple sources of uncertainties could lead to substantial differences in model outputs and jeopardize risk assessments. We evaluate uncertainties in coupled species distribution-metapopulation dynamics models and focus on two often underappreciated sources of uncertainty: the choice of general circulation model (GCM) and demographic parameter uncertainty of the metapopulation model. We rank the risks associated with potential climate changes and habitat loss on projected range margin dynamics of the Hooded Warbler (Setophaga citrina). Location: Breeding range of the Hooded Warbler, North America. Methods: Using SDMs, we quantified variability in projected future distributions using four GCMs and a consensus model at the biogeographic scale and assessed the propagation of uncertainty through to metapopulation viability projections. We applied a global sensitivity analysis to the coupled species distribution-metapopulation models to rank the influence of choice of GCM, parameter uncertainty and simulated effects of habitat loss on metapopulation viability, thereby addressing error propagation through the whole modelling process. Results: The Hooded Warbler range was consistently projected to shift north: choice of GCMs influenced the magnitude of change, and variability was spatially structured. Variability in the choice of GCMs propagated through to metapopulation viability at the northern range boundary. Although viability measures were sensitive to the GCM used, measures of direct habitat loss were more influential. Despite the high ranking of vital rates in the global sensitivity analysis, direct habitat loss had a larger negative influence on extinction risk than potential future climate changes. Main conclusions: This work underscores the importance of a global sensitivity analysis framework applied to coupled models to disentangle the relative influence of uncertainties on projections. The use of multiple GCMs enabled the exploration of a range of possible outcomes relative to the consensus GCM, helping to inform risk estimates. Ranking uncertainties informs the prioritization of management actions for species affected by dynamic anthropogenic threats over multiple spatial scales. © 2013 John Wiley & Sons Ltd.
Gratto-Trevor C.L.,Environment Canada |
Abbott S.,Bird Studies Canada
Canadian Journal of Zoology | Year: 2011
There are only about 8000 Piping Plovers (Charadrius melodus Ord, 1834) in existence. Because they depend on environments that are under intense human pressures and controls in both their breeding and wintering grounds, these birds and their habitats are highly managed in many areas across their range. Efforts to recover this endangered and threatened species have engaged thousands of people from Newfoundland to the Caribbean, and have provoked a ground-swell of public support and, at times, fury, as well as a considerable body of research. Although populations have increased substantially in the U.S. Atlantic and U.S. Great Lakes, this is not true of all regions. Significant issues still exist with respect to the efficacy of predator management; need for more accurate model input information; effects of climate, pollutants, and water management; habitat loss and degradation from recreation and development; and whether the cost and effort of management for this species can be maintained or increased where needed.
Avery-Gomm S.,University of British Columbia |
O'Hara P.D.,Environment Canada |
Kleine L.,University of Puget Sound |
Bowes V.,Ministry of Agriculture Animal Health Center |
And 2 more authors.
Marine Pollution Bulletin | Year: 2012
Marine plastic debris is a global issue, which highlights the need for internationally standardized methods of monitoring plastic pollution. The stomach contents of beached northern fulmar (Fulmarus glacialis) have proven a cost-effective biomonitor in Europe. However, recent information on northern fulmar plastic ingestion is lacking in the North Pacific. We quantified the stomach contents of 67 fulmars from beaches in the eastern North Pacific in 2009-2010 and found that 92.5% of fulmars had ingested an average of 36.8 pieces, or 0.385. g of plastic. Plastic ingestion in these fulmars is among the highest recorded globally. Compared to earlier studies in the North Pacific, our findings indicate an increase in plastic ingestion over the past 40. years. This study substantiates the use of northern fulmar as biomonitors of plastic pollution in the North Pacific and suggests that the high levels of plastic pollution in this region warrant further monitoring. © 2012 Elsevier Ltd.
News Article | November 17, 2016
OTTAWA, ON--(Marketwired - November 16, 2016) - Canadian Geographic announced the gray jay as Canada's national bird at the annual dinner of the magazine's publisher, the Royal Canadian Geographical Society, at the Canadian War Museum in Ottawa. "We are proud and pleased to recommend the gray jay as the ideal candidate for a national bird for Canada," said Aaron Kylie, Canadian Geographic editor. "Canadians' overwhelming interest in choosing a national bird really impressed us. We are honoured to recommend the gray jay as a fresh symbol of our collective passion for natural environments, and our concern for their conservation and stewardship." The choice of the gray jay was the culmination of Canadian Geographic's nearly two-year-long National Bird Project. The gray Jay is truly Canada's bird with traits that symbolize the Canadian spirit. Their range is nearly exclusive to Canada, and is found in every province and territory. They are a tough bird. The gray jay thrives in winter, nesting in the harshest, darkest month of the year and has been recorded incubating eggs in snowstorms at temps as cold as -30C. The gray jay is extremely friendly and an intelligent bird. It enjoys the same brain-to-body ratio as dolphins and chimps -- nearly that of humans. It has been known for centuries as a companion to Indigenous Peoples, early explorers and outdoor enthusiasts. Its chattering and whistles are considered an early warning to hunters of nearby predators. There are stories of Gwich'in guides in the Yukon who tell of gray jays singing from tree to tree to lead a lost hunter home. Canadian Geographic's National Bird Project, launched in 2015, and attracted Canadians in surprisingly large numbers. The opportunity to cast a ballot for a favoured bird resulted in 50,000 votes, with many adding an essay or commentary. Canadian Geographic also sought the opinions of the leading experts and ornithologists in the country, including those of the its conservation partner, Bird Studies Canada. Five birds garnered the most votes, including three which are already provincial birds: Snowy owl (Quebec), black-capped chickadee (New Brunswick), common loon (Ontario), Canada goose and gray jay. In September, the Honorable Catherine McKenna, Minister of the Environment, addressed a panel debate where five impassioned Canadians advocated for one of final species. The following day the hashtag #CanadaBird trended number one in Canada. "Canadians' enthusiasm for the National Bird Project tapped into something beyond expressing a preference for a particular species," said the Honourable Catherine McKenna, Minister of the Environment. "The project ignited a groundswell of public support because those taking part recognized they were joining a movement to identify a new national symbol of pride, identity and belonging on the cusp of the country's 150th birthday."
Mcguire L.P.,University of Western Ontario |
Guglielmo C.G.,University of Western Ontario |
Mackenzie S.A.,University of Western Ontario |
Taylor P.D.,Bird Studies Canada |
Taylor P.D.,Acadia University
Journal of Animal Ecology | Year: 2012
Some bat species make long-distance latitudinal migrations between summer and winter grounds, but because of their elusive nature, few aspects of their biology are well understood. The need for migratory stopover sites to rest and refuel, such as used by birds, has been repeatedly suggested, but not previously tested empirically in bats. We studied migrating silver-haired bats (Lasionycteris noctivagans) at Long Point, ON, Canada. We used digital radio-transmitters to track 30 bats using an array of five towers that effectively covered the entire region (c. 20×40km). We measured stopover duration and departure direction, and documented movement patterns, foraging activity and roost sites. We measured body composition on arrival using quantitative magnetic resonance and simulated long-distance migration using observed body composition to predict migration range and rate. Migration occurred in two waves (late August and mid-September). Most bats stayed 1-2days, although two remained >2weeks. One third of the bats foraged while at the site, many foraging opportunistically on nights when rain precluded continued migration. Bats roosted in a variety of tree species and manmade structures in natural and developed areas. Half of the bats departed across Lake Erie (minimum crossing distance c. 38km) while half departed along the shoreline. Simulations predicted a migration rate of c. 250-275km per day and suggest that all but one of the bats in our study carried sufficient fuel stores to reach the putative wintering area (estimated distance 1500km) without further refuelling. Our results suggest that migrating bats stopover for sanctuary or short-term rest as opposed to extended rest and refuelling as in many songbirds. Daily torpor could reduce energy costs when not in flight, minimizing the need for extended stopovers and allowing bats to potentially complete their migration at a fraction of the time and energy cost of similar sized birds. © 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society.
Melles S.J.,University of Toronto |
Fortin,University of Toronto |
Lindsay K.,Natural Resources Canada |
Badzinski D.,Bird Studies Canada
Global Change Biology | Year: 2011
Species' ranges are dynamic, shifting in response to a large number of interrelated ecological and anthropogenic processes. Climate change is thought to be one of the most influential drivers of range shifts, but the effects of other confounded ecological processes are often ignored even though these processes may modify expected range responses to climate change. To determine the relative effects of climate, forest availability, connectivity, and biotic processes such as immigration and establishment, we examine range changes occurring in a species of bird, the Hooded Warbler (Wilsonia citrina). We focus predominantly on the periphery of the species' northern range in Canada but we also examine data from the entire species' range. Nesting records in southern Ontario were obtained from two breeding bird Atlases of Ontario separated by a period of 20 years (1981-1985 and 2001-2005), and the rate of range expansion was estimated by comparing the number of occupied areas in each Atlas. Twelve hypotheses of the relationship between the rate of range expansion and factors known to influence range change were examined using model-selection techniques and a mixed modeling approach (zero-inflated Poisson's regression). Cooler temperatures were positively related to a lack of range expansion indicating that climate constrained the species' distribution. Establishment probability (based on the number of occupied, neighboring Atlas squares) and immigration from populations to the south (estimated using independent data from the North American Breeding Bird Survey) were also important predictors of range expansion. These biotic process variables can mask the effects of forest availability and connectivity on range expansion. Expansion due to climate change may be slower in fragmented systems, but the rate of expansion will be influenced largely by biotic processes such as proximity to neighboring populations. © 2010 Blackwell Publishing Ltd.
Chin A.T.M.,York University |
Tozer D.C.,Bird Studies Canada |
Fraser G.S.,York University
Journal of Great Lakes Research | Year: 2014
Marsh bird habitats are influenced by water levels which may pose challenges for interpreting bird-based indices of wetland health. We determined how much fluctuating water levels and associated changes in emergent vegetation influence the Index of Marsh Bird Community Integrity (IMBCI) using data collected in Great Lakes coastal wetlands by participants in Bird Studies Canada's Great Lakes Marsh Monitoring Program. IMBCI scores for 90 wetlands in Lake Erie and 131 wetlands in Lake Ontario decreased with decreasing water levels due to decreasing number of marsh-dependent species in Lake Erie and perhaps also in Lake Ontario. The average magnitude of the decrease in scores between extremely high and low water periods for wetlands with sufficient data was 15% in Lake Erie where water dropped 0.9. m on average (n=11 wetlands) and 18% in Lake Ontario where water dropped 0.5. m (n=7). Scores in Lake Erie increased with increasing Typha due to increasing numbers of marsh-dependent species and decreased with increasing Phragmites due to increasing numbers of generalist species. The opposite was observed in Lake Ontario, perhaps due to denser Typha and sparser Phragmites. Scores were explained by the naturally fluctuating water levels of Lake Erie, which favored Phragmites expansion and the regulated water levels of Lake Ontario which promoted Typha expansion. Scores were influenced by fluctuating water levels and associated changes in emergent vegetation. Inter-annual water level fluctuations should be considered when interpreting any indicator of wetland health that is based on marsh-dependent bird species. © 2014 Elsevier B.V.
Nebel S.,University of Western Ontario |
Mills A.,Acadia University |
McCracken J.D.,Bird Studies Canada |
Taylor P.D.,Bird Studies Canada
Avian Conservation and Ecology | Year: 2010
North American birds that feed on aerial insects are experiencing widespread population declines. An analysis of the North American Breeding Bird Survey trend estimates for 1966 to 2006 suggests that declines in this guild are significantly stronger than in passerines in general. The pattern of decline also shows a striking geographical gradient, with aerial insectivore declines becoming more prevalent towards the northeast of North America. Declines are also more acute in species that migrate long distances compared to those that migrate short distances. The declines become manifest, almost without exception, in the mid 1980s. The taxonomic breadth of these downward trends suggests that declines in aerial insectivore populations are linked to changes in populations of flying insects, and these changes might be indicative of underlying ecosystem changes. © 2010 by the author(s).
Tozer D.C.,Bird Studies Canada
Journal of Great Lakes Research | Year: 2016
Using data from 21,546 point counts conducted by volunteers in Bird Studies Canada's Great Lakes Marsh Monitoring Program, I assessed whether occupancy of 15 breeding marsh bird species increased or decreased throughout the southern portion of the Great Lakes basin between 1996 and 2013. I accounted for differences in detection probability, addressed spatial autocorrelation, and assessed whether initial occupancy in 1996 and subsequent colonization or extinction at a site within and across species was influenced by site, wetland, and landscape scale covariates. Occupancy of 9 of 15 (60%) species significantly decreased, whereas occupancy of only 1 (7%) species significantly increased. The results show the power of citizen science and suggest that the largest number of decreasing marsh-dependent breeding bird species will benefit from conserving, restoring, or creating large wetlands surrounded by limited urban land use, and from addressing issues within International Joint Commission Areas of Concern. Plus, individual or smaller groups of decreasing species will also benefit from conserving, restoring, or creating robust-emergent-dominated but interspersed, purple loosestrife (Lythrum salicaria)-free, Phragmites-free wetlands surrounded by higher proportions of wetland cover in the surrounding landscape, and from addressing issues within Great Lakes coastal wetlands. These actions will help promote colonization or reduce extinction and help slow or maybe even reverse declining trends in occupancy among decreasing species across the southern portion of the Great Lakes basin. © 2015 International Association for Great Lakes Research.
Crewe T.L.,University of Western Ontario |
McCracken J.D.,Bird Studies Canada
Annals of the Entomological Society of America | Year: 2015
In Canada, the monarch butterfly, Danaus plexippus (L.), is designated a species of "special concern." During their southward journey each year, hundreds of thousands of monarchs funnel through Long Point, Lake Erie in Canada. Standardized daily counts of migrating monarchs have been conducted at two sites on Long Point for 20 consecutive years (1995-2014). Using a Bayesian framework, we estimated long-term trends in the number of migrants passing through Long Point. Over the 20-yr period, credible intervals for trends estimated at each site overlapped, with an estimated decline of 5.11%yr-1 across sites. However, trajectories differed between sites. At the more inland site, a more constant 7.78%yr-1 decline was detected, but at the tip of the peninsula, counts increased by 10.04%yr-1 from 1995-2005, followed by a decline of 11.9%yr-1 from 2004-2014. This resulted in an estimated 20-yr decline of 2.74%yr-1 at this site. Lower and less variable counts since 2010 appear to be driving the apparent long-term population declines. Relative to the tip site, counts from the more inland site are less likely to be biased by large accumulations of monarchs blown off-course during headwinds or stopping over to replenish fuel supplies. Trends from the more inland site also show strong correspondence with declines in egg production and milkweed abundance in the upper Midwest, which suggests that the number of individuals counted on migration is evidence of a potentially broader-scale condition. Additional years of data should be collected to determine whether the apparent decline will continue. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America.