Robertson G.J.,Environment Canada |
Fifield D.A.,Environment Canada |
Montevecchi W.A.,Memorial University of Newfoundland |
Gaston A.J.,Environment Canada |
And 12 more authors.
Journal of Ocean Technology | Year: 2012
Obtaining useful information on marine birds that can aid in oil spill (and other hydrocarbon release) risk and damage assessments in offshore environments is challenging. Technological innovations in miniaturization have allowed archival data loggers to be deployed successfully on marine birds vulnerable to hydrocarbons on water. A number of species, including murres (both Common, Uria aalge, and Thick-billed, U. lomvia) have been tracked using geolocation devices in eastern Canada, increasing our knowledge of the seasonality and colony-specific nature of their susceptibility to oil on water in offshore hydrocarbon production areas and major shipping lanes. Archival data tags are starting to resolve questions around behaviour of vulnerable seabirds at small spatial scales relevant to oil spill impact modelling, specifically to determine the duration and frequency at which birds fly at sea. Advances in data capture methods using voice activated software have eased the burden on seabird observers who are collecting increasingly more detailed information on seabirds during ship-board and aerial transects. Computer programs that integrate seabird density and bird behaviour have been constructed, all with a goal of creating more credible seabird oil spill risk and damage assessments. In this paper, we discuss how each of these technological and computing innovations can help define critical inputs into seabird risk and damage assessments, and when combined, can provide a more realistic understanding of the impacts to seabirds from any hydrocarbon release.
Andres B.A.,U.S. Fish and Wildlife Service |
Smith P.A.,Smith and Associates Ecological Research Ltd |
Morrison R.I.G.,Carleton University |
Gratto-Trevor C.L.,Environment Canada |
And 2 more authors.
Wader Study Group Bulletin | Year: 2012
We re-assessed the population size and trend of 52 species and 75 taxa of shorebirds that occur in North America by reviewing published papers, soliciting unpublished data, and seeking the opinions of experts. New information resulted in changing population estimates for 35 of the 71 taxa that could be compared directly to the estimates published in 2006; from this comparison, 28 estimates increased and seven decreased. Almost all of the increases (88%) were the result of more comprehensive surveys being conducted or re-analyses of existing data rather than actual increases in numbers. Retaining the previous estimate was almost always due to a lack of new information. Recent trend analysis indicates that many shorebird populations have stabilized in recent years after large declines during the early 1980s and mid-1990s. Although many shorebird populations listed as threatened or endangered by the U.S. and Canadian governments have increasing population trends, none have reached recovery targets. Information on population trends remains virtually unknown for 25% of the shorebirds occurring in North America, and surveys are needed to determine the state of these populations.
How well do regional or national breeding bird survey data predict songbird population trends at an intact boreal site? [Les données régionales et nationales du relevé des oiseaux nicheurs permettent-elles de bien prédire la tendance des populations de passereaux dans un secteur boréal vierge?]
Machtans C.S.,Environment Canada |
Kardynal K.J.,Environment Canada |
Smith P.A.,Smith and Associates Ecological Research Ltd
Avian Conservation and Ecology | Year: 2014
A study to monitor boreal songbird trends was initiated in 1998 in a relatively undisturbed and remote part of the boreal forest in the Northwest Territories, Canada. Eight years of point count data were collected over the 14 years of the study, 1998-2011. Trends were estimated for 50 bird species using generalized linear mixed-effects models, with random effects to account for temporal (repeat sampling within years) and spatial (stations within stands) autocorrelation and variability associated with multiple observers. We tested whether regional and national Breeding Bird Survey (BBS) trends could, on average, predict trends in our study area. Significant increases in our study area outnumbered decreases by 12 species to 6, an opposite pattern compared to Alberta (6 versus 15, respectively) and Canada (9 versus 20). Twenty-two species with relatively precise trend estimates (precision to detect > 30% decline in 10 years; observed SE ≤ 3.7%/year) showed nonsignificant trends, similar to Alberta (24) and Canada (20). Precision-weighted trends for a sample of 19 species with both reliable trends at our site and small portions of their range covered by BBS in Canada were, on average, more negative for Alberta (1.34% per year lower) and for Canada (1.15% per year lower) relative to Fort Liard, though 95% credible intervals still contained zero. We suggest that part of the differences could be attributable to local resource pulses (insect outbreak). However, we also suggest that the tendency for BBS route coverage to disproportionately sample more southerly, developed areas in the boreal forest could result in BBS trends that are not representative of range-wide trends for species whose range is centred farther north. © 2014 by the author(s).
Smith P.A.,Smith and Associates Ecological Research Ltd. |
Gratto-Trevor C.L.,Environment Canada |
Collins B.T.,Environment Canada |
Fellows S.D.,U.S. Fish and Wildlife Service |
And 8 more authors.
Waterbirds | Year: 2012
Counts of Semipalmated Sandpiper (Calidris pusilla) at some migratory stopover sites have shown pronounced declines over the last 35 years. Counts from breeding grounds avoid sources of bias that have proven troublesome for trends estimated from migration surveys. Published and unpublished data were reviewed to examine trends in densities of Semipalmated Sandpipers at breeding sites across Alaska and arctic Canada. Information was sparse, and some comparisons are tenuous because methods varied over time. Valid time series were obtained for 13 sites across the species' range. In Alaska, Semipalmated Sandpipers either increased or were at least stable at six sites and decreased at one site. Surveys at both sites in the central portion of the range suggested no change in abundance. In the eastern portion of the range, trends were variable: decreases were observed at two sites, a possible increase at one site, and no change at another. Thus, the species was generally increasing or stable in the western and central portions of the range and had an uncertain status in the east. Also, trends in presence/absence data were analyzed from the Northwest Territories and Nunavut Checklist Survey. The species was observed at 345 sites, and results suggested that birds increased significantly in prevalence (assumed here to be correlated with abundance) across arctic Canada between 1987 and 2007. Overall, data from the breeding grounds do not support a range-wide decline in the abundance of Semipalmated Sandpipers, although data are insufficient for the long-billed population from the eastern Arctic for which specific conservation concerns exist.
Bolduc E.,University of Quebec at Rimouski |
Casajus N.,University of Quebec at Rimouski |
Legagneux P.,University of Quebec at Rimouski |
McKinnon L.,University of Quebec at Rimouski |
And 7 more authors.
Canadian Entomologist | Year: 2013
Arctic arthropods are essential prey for many vertebrates, including birds, but arthropod populations and phenology are susceptible to climate change. The objective of this research was to model the relationship between seasonal changes in arthropod abundance and weather variables using data from a collaborative pan-Canadian (Southampton, Herschel, Bylot, and Ellesmere Islands) study on terrestrial arthropods. Arthropods were captured with passive traps that provided a combined measure of abundance and activity (a proxy for arthropod availability to foraging birds). We found that 70% of the deviance in daily arthropod availability was explained by three temperature covariates: mean daily temperature, thaw degree-day, and thaw degree-day2. Models had an adjusted R 2 of 0.29-0.95 with an average among sites and arthropod families of 0.67. This indicates a moderate to strong fit to the raw data. The models for arthropod families with synchronous emergence, such as Tipulidae (Diptera), had a better fit (average adjusted R 2 of 0.80) than less synchronous taxa, such as Araneae (R 2 = 0.60). Arthropod abundance was typically higher in wet than in mesic habitats. Our models will serve as tools for researchers who want to correlate insectivorous bird breeding data to arthropod availability in the Canadian Arctic. Copyright © 2013 Entomological Society of Canada.
Dickson D.L.,Environment Canada |
Smith P.A.,Smith and Associates Ecological Research Ltd.
Journal of Wildlife Management | Year: 2013
The southeast Beaufort Sea is a critical spring staging area for common and king eiders (Somateria mollissima v-nigrum, S. spectabilis), and is for many the final stop before they reach their breeding grounds throughout the western Canadian Arctic. The region also has significant oil and gas potential, and the recent approval of a pipeline through the Mackenzie Valley may make development of these resources economically viable. We used satellite telemetry to determine the distribution and habitat use of eiders staging in the southeast Beaufort Sea in spring, and the overlap of eiders with oil and gas exploration. From 2004 to 2009, we monitored 51 eiders equipped with platform terminal transmitters (PTTs) throughout spring migration (May-June). We compared the marine habitats used by each species, and evaluated habitat preferences using resource selection functions. The location and extent of the flaw lead (open water along the interface between mobile pack ice and stationary landfast ice) at the time when eiders were staging varied among years, but both species showed a strong preference for use of flaw lead habitats. This preference was stronger for common eiders than for king eiders, which also used pack ice extensively. Common eiders generally occurred near the landfast ice edge, whereas king eiders were just as often nearer to the pack ice edge of the flaw lead. Average water depth (±SE) for common eiders was 22 ± 2 m compared to 30 ± 1 m for king eiders. Kernel density estimators showed that eiders generally occurred in lower densities in areas of otherwise suitable habitat off the Mackenzie River delta. We suggest that this is a result of the highly turbid water discharged by the Mackenzie River, which limits visibility. Oil and gas exploration overlapped significantly with the areas used by eiders. The high density of birds using the restricted and ice-rich flaw lead habitats indicates that an accidental spill in the region could be catastrophic for Canada's western Arctic eider populations. © 2013 The Wildlife Society.
Kenyon Ross R.,Environment Canada |
Smith P.A.,Smith and Associates Ecological Research Ltd. |
Campbell B.,Environment Canada |
Friis C.A.,Environment Canada |
Guy Morrison R.I.,Carleton University
Waterbirds | Year: 2012
Shorebirds are thought to be declining across North America but trend analyses for migrant shorebirds at interior sites in eastern North America have not been updated since the late 1990s. Data from a volunteer-based survey at stopover sites throughout Ontario were used to assess population trends of shorebirds over the period 19742009. Surveyors carried out 7,135 surveys of 258 sites and recorded 538,744 individuals of 43 shorebird species. Of 19 taxa for which trends were estimated, 17 appeared to be declining in abundance. Precision of the trend estimates was generally poor and only three declines were significant at ? = 0.05. Total numbers of shorebirds recorded on surveys declined by four per cent per year, resulting in an estimated decrease in abundance of greater than 75% over the 35 years of observation. Rate of decline may be increasing for some species as declines for twelve species were larger for the period 19892009 vs. 19741989, and six species showed significant declines in the latter period whereas none did in the former period. Relating these declines in abundance at the surveyed sites to population declines is complicated by several potential sources of survey bias including changes in turnover rates and in migration timing and distributions of the species. However, given that these results are consistent with those of other migration surveys as well as those on the breeding and the wintering grounds, the most parsimonious explanation remains a widespread decline in shorebird populations.