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Notaro M.,University of Wisconsin - Madison | Lorenz D.,University of Wisconsin - Madison | Schummer M.,Long Point Waterfowl | Schummer M.,State University of New York at Oswego
Journal of Climate | Year: 2014

Statistically downscaled climate projections fromnine global climatemodels (GCMs) are used to force a snow accumulation and ablation model (SNOW-17) across the central-eastern North American Landscape Conservation Cooperatives (LCCs) to develop high-resolution projections of snowfall, snow depth, and winter severity index (WSI) by themiddle and late twenty-first century.Here, projections of a cumulativeWSI (CWSI) known to influence autumn-winter waterfowl migration are used to demonstrate the utility of SNOW-17 results. The application of statistically downscaled climate data and a snow model leads to a better representation of lake processes in the Great Lakes basin, topographic effects in the Appalachian Mountains, and spatial patterns of climatological snowfall, compared to the original GCMs.Annual mean snowfall is simulated to decline across the region, particularly in earlywinter (December-January), leading to a delay in themean onset of the snow season. Because of a warming-induced acceleration of snowmelt, the percentage loss in snow depth exceeds that of snowfall. Across the Plains and Prairie Potholes LCC and the Upper Midwest and Great Lakes LCC, daily snowfall events are projected to become less common butmore intense. The greatest reductions in the number of days per year with a present snowpack are expected close to the historical position of the -5°C isotherm in December-March, around 44°N. The CWSI is projected to decline substantially during December-January, leading to increased likelihood of delays in timing and intensity of autumn-winter waterfowl migrations. © 2014 American Meteorological Society.


Brady C.,University of Western Ontario | Petrie S.,Long Point Waterfowl | Schummer M.,Long Point Waterfowl | Badzinski S.,Long Point Waterfowl | And 2 more authors.
Environmental Pollution | Year: 2013

Accumulation of selenium (Se) by lesser and greater scaup (Aythya affinis, A. marila) at staging and wintering areas could have contributed to the decline in their continental population. We exposed lesser scaup to background (0.8 μg/g), moderate (8.1 μg/g) and high (20.7 μg/g) levels of dietary Se in captivity and measured survival rates and indices of health in relation to hepatic Se concentrations. There was 100% survival in scaup exposed to Se for 10-weeks (average staging duration at Great Lakes), but ducks in the high treatment group had less lipids. There was 93% survival after 23-weeks (average wintering duration at Great Lakes), but no differences among treatment groups in body composition. There were no effects of Se on oxidative stress and cell-mediated immunity; rather we recorded immuno-stimulatory effects on antibody production. Results from our captive study suggest Se alone did not cause the continental decline in scaup populations. © 2012 Elsevier Ltd. All rights reserved.


Schummer M.L.,Long Point Waterfowl | Schummer M.L.,Mississippi State University | Badzinski S.S.,Long Point Waterfowl | Petrie S.A.,Long Point Waterfowl | And 2 more authors.
Archives of Environmental Contamination and Toxicology | Year: 2010

Numbers of wintering sea ducks, including buffleheads (Bucephala albeola; BUFF), common goldeneyes (Bucephala clangula; COGO), and long-tailed ducks (Clangula hyemalis; LTDU), increased substantially at Lake Ontario after Dreissenid mussels (Dreissena bugensis and D. polymorpha) colonized the Great Lakes. Invertebrates, including Dreissenid mussels, are major diving duck prey items that can transfer some trace elements, such as selenium (Se) to higher trophic levels. Se can be problematic for waterfowl and it often has been detected at elevated levels in organisms using the Great Lakes. There are, however, few data on hepatic Se concentrations in sea ducks, particularly during the winter at Lake Ontario. In this study, we evaluated interspecific differences and temporal trends in hepatic Se concentrations among BUFF (n = 77), COGO (n = 77), and LTDU (n = 79) wintering at Lake Ontario. All three species accumulated Se throughout winter, but COGO did so at a higher rate than did BUFF and LTDU. Overall, Se concentrations were higher in LTDU [x̄= 22.7; 95% CI = 20.8-24.8 μg/g dry weight (dw)] than in BUFF (x̄= 1 2.3; 95% CI = 11.6-13.1 μg/g dw) and COGO (x̄= 12.0; 95% CI = 10.7-3.5 μg/g dw) throughout the winter. Se concentrations were deemed elevated (>33 μg/g dw) in 0%, 5%, and 19% of BUFF, COGO, and LTDU, respectively. Presently there are no data on Se toxicity end points for these species, so it is unclear how acquiring concentrations of these magnitudes affect their short- and long-term health or reproduction. © 2009 Springer Science+Business Media, LLC.


Schummer M.L.,Long Point Waterfowl | Petrie S.A.,Long Point Waterfowl | Badzinski S.S.,Long Point Waterfowl | Deming M.,University of Western Ontario | And 2 more authors.
Archives of Environmental Contamination and Toxicology | Year: 2011

Contaminant inputs to the lower Great Lakes (LGL) have decreased since the 1960s and 1970s, but elemental contaminants continue to enter the LGL watershed at levels that are potentially deleterious to migratory waterfowl. Mute swans (Cygnus olor) using the LGL primarily eat plants, are essentially nonmigratory, forage exclusively in aquatic systems, and have increased substantially in number in the last few decades. Therefore, mute swans are an ideal sentinel species for monitoring elemental contaminants available to herbivorous and omnivorous waterfowl that use the LGL. We investigated hepatic concentrations, seasonal dynamics, and correlations of elements in mute swans (n = 50) collected at Long Point, Lake Erie, and Lake St. Clair from 2001 to 2004. Elements detected in liver at levels potentially harmful to waterfowl were copper (Cu) [range 60.3 to 6063.0 μg g -1 dry weight (dw)] and selenium (SE; range 1.6 to 37.3 μg g -1 dw). Decreases in aluminum, Se, and mercury (Hg) concentrations were detected from spring (nesting) through winter (nonbreeding). Elemental contaminants may be more available to waterfowl during spring than fall and winter, but study of seasonal availability of elements within LGL aquatic systems is necessary. From April to June, 68% of mute swans had Se levels >10 μg g -1, whereas only 18% of swans contained these elevated levels of Se from July to March. An increase in the number of mute swans at the LGL despite elevated levels of Cu and Se suggests that these burdens do not substantially limit their reproduction or survival. Se was correlated with Cu (r = 0.85, p < 0.01) and Hg (r = 0.65, p < 0.01), which might indicate interaction between these elements. Some element interactions decrease the toxicity of both elements involved in the interaction. We recommend continued research of elemental contaminant concentrations, including detailed analyses of biological pathways and element forms (e.g., methylmercury) in LGL waterfowl to help determine the role of element interactions on their toxicity in waterfowl. © 2011 Springer Science+Business Media, LLC.


Ware L.L.,University of Western Ontario | Petrie S.A.,Long Point Waterfowl | Badzinski S.S.,Long Point Waterfowl | Bailey R.C.,Cape Breton University
Archives of Environmental Contamination and Toxicology | Year: 2011

One hypothesis for the decline of the North American greater (Aythya marila) and lesser (A. affinis) scaup population is that contaminant burdens acquired on wintering or staging areas impair reproduction or cause lethal or sublethal health effects. Recent studies have found increased selenium (Se) concentrations in scaup but have focused on the fall and spring staging periods. From January to March 2006 and December to March 2006 and 2007, we analyzed liver tissues collected from greater scaup wintering in western Lake Ontario for 16 trace elements. We also measured Se concentrations in greater scaup blood and Dreissenid mussel tissue. Se was the only trace element that occurred at increased concentrations (>10 μg/g liver dry weight) in a substantial proportion (99%) of greater scaup livers. We also found that hepatic Se concentrations increased throughout winter and were increased in nearly all birds from January to March, suggesting that accumulation of this trace element occurred soon after their arrival in fall. Se concentrations were similar in male and female birds, but juvenile birds had higher concentrations than did adults. Blood Se concentrations were correlated to liver Se concentrations in 2006 only, suggesting that blood Se concentration is an unreliable predictor of liver concentration. Se in Dreissenid mussels generally decreased with mussel size and did not change throughout winter. Overall, our results suggest that greater scaup wintering on western Lake Ontario acquire sufficiently high Se concentrations to potentially impact their health. Thus, several indicators of health and survival should be examined in relation to Se concentrations in wintering scaup. © 2010 Springer Science+Business Media, LLC.


Meyer S.W.,University of Western Ontario | Meyer S.W.,Environment Canada | Badzinski S.S.,Long Point Waterfowl | Petrie S.A.,Long Point Waterfowl | Ankney C.D.,University of Western Ontario
Journal of Wildlife Management | Year: 2010

Common reed (Phragmites australis) forms dense stands with deep layers of residual organic matter that negatively affects plant diversity and possibly habitat use by wetland birds. We sought to determine whether seasonal relative abundance and species richness of birds varied among 3 habitat types in Great Lakes coastal wetland complexes recently invaded by common reed. We used fixed-distance point counts to determine species relative abundances and species richness in edge and interior locales within common reed, cattail (Typha spp.), and meadow marsh habitats of various sizes during 2 summers (2001 and 2002) and 1 autumn (2001) at Long Point, Lake Erie, Ontario, Canada. We found that total relative abundance and species richness of birds were greater in common reed habitat compared to cattail or meadow marsh habitats. However, we also found that relative abundance of marsh-nesting birds was greater in meadow marsh habitat than in cattail and common reed during summer. Lastly, we found that, irrespective of habitat type, habitat edges had higher total relative abundance and species richness of birds than did habitat interiors. Our results show that common reed provides suitable habitat for a diversity of landbirds during summer and autumn but only limited habitat for many marsh-nesting birds during summer. Based on these results, we recommend restoration of meadow marsh habitat through reduction of common reed in Great Lakes wetlands where providing habitat for breeding marsh-nesting birds is an objective. Managers also might consider reducing the size of nonnative common reed stands to increase edge effect and use by birds, possibly including wetland birds. © 2010 The Wildlife Society.


Ashley P.,Long Point Waterfowl | Hobson K.A.,Environment Canada | van Wilgenburg S.L.,Environment Canada | North N.,Natural Resources Canada | Petrie S.A.,Long Point Waterfowl
Avian Conservation and Ecology | Year: 2010

Understanding source-sink dynamics of game birds is essential to harvest and habitat management but acquiring this information is often logistically and financially challenging using traditional methods of population surveys and banding studies. This is especially true for species such as the American Black Duck (Anas rubripes), which have low breeding densities and extensive breeding ranges that necessitate extensive surveys and banding programs across eastern North America. Despite this effort, the contribution of birds fledged from various landscapes and habitat types within specific breeding ranges to regional harvest is largely unknown but remains an important consideration in adaptive harvest management and targeted habitat conservation strategies. We investigated if stable isotope (δD, δ13C, δ15N) could augment our present understanding of connectivity between breeding and harvest areas and so provide information relevant to the two main management strategies for black ducks, harvest and habitat management. We obtained specimens from 200 hatch-year Black Duck wings submitted to the Canadian Wildlife Service Species Composition Survey. Samples were obtained from birds harvested in Western, Central, and Eastern breeding/harvest subregions to provide a sample representative of the range and harvest rate of birds harvested in Canada. We sampled only hatch-year birds to provide an unambiguous and direct link between production and harvest areas. Marine origins were assigned to 12%, 7%, and 5% of birds harvested in the Eastern, Central, and Western subregions, respectively. In contrast, 32%, 9%, and 5% of birds were assigned, respectively, to agricultural origins. All remaining birds were assigned to nonagricultural origins. We portrayed probability of origin using a combination of Bayesian statistical and GIS methods. Placement of most eastern birds was western Nova Scotia, eastern New Brunswick, Prince Edward Island, and southern Newfoundland. Agricultural birds from the Central region were consistent with the Saguenay region of Québec and the eastern claybelt with nonagricultural birds originating in the boreal. Western nonagricultural birds were associated with broad boreal origins from southern James Bay to Lake of the Woods and east to Cochrane, Ontario. Our work shows that the geographic origins, landscape, and habitat associations of hatch-year Black Ducks can be inferred using this technique and we recommend that a broad-scale isotopic study using a large sample of Canadian and US harvested birds be implemented to provide a continental perspective of source-sink population dynamics. © 2010 by the author(s).


Schummer M.L.,Long Point Waterfowl | Petrie S.A.,Long Point Waterfowl | Badzinski S.S.,Long Point Waterfowl | Badzinski S.S.,Environment Canada | And 2 more authors.
Archives of Environmental Contamination and Toxicology | Year: 2012

Common loons (Gavia immer) are piscivorous, high-trophic level feeders that bioaccumulate inorganic contaminants at concentrations that can negatively impact their health and reproduction. Concentrations of inorganic contaminants, especially mercury (Hg), in blood, organs, and muscle have been quantified in common loons on breeding grounds, but these data are limited for migrating loons. We investigated sex- and age-related hepatic concentrations of inorganic contaminants in common loons (n = 53) that died from botulism and were salvaged at a Great Lakes staging area (i.e., Long Point, Lake Erie) during November 2005. We also investigated if hepatic concentrations of inorganic contaminants influenced lipid, protein, and mineral in our sample of migrant common loons. Last, we determined if there was correlation between Hg and selenium (Se). Consistent with data from breeding grounds, mean concentrations of Hg in liver were approximately 2.5 times greater in adult (x̄ = 14.64 ± 16.69 μg g -1) compared with juvenile birds (x̄ = 3.99 ± 2.27 μg g -1). Elements detected in liver at potentially harmful levels were Hg and Se, of which lipid reserves varied negatively with Hg concentrations but positively with Se concentrations. In addition, Hg and Se were correlated (r = 0.65) at greater then a demethylation threshold (total Hg ≥ 8.5 μg g -1 dw) but not lower than that. Concentrations of inorganic contaminants did not influence protein and mineral levels in our sample of common loons. Our results suggest that Hg accumulation negatively affects lipid levels in migrant common loons. Results are also consistent with a nontoxic Hg-Se protein complex protecting loons migrating through areas that are relatively Se rich. Although the acquisition of Se during the nonbreeding season may decrease the toxicity of Hg, future research should consider the synergistic Hg-Se effect on reproduction in common loons that migrate through Se-rich locales, such as the Great Lakes. © Springer Science+Business Media, LLC 2011.


Jobin B.,Environment Canada | Mazerolle M.J.,University of Québec | Bartok N.D.,Long Point Waterfowl | Bazin R.,Environment Canada
Wilson Journal of Ornithology | Year: 2013

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, Québec, and Manitoba, respectively. Occupancy probability in the first year of the study was lower in Québec sites (0.26) compared to Manitoba sites (0.53). However, Québec 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. © 2013 by the Wilson Ornithological Society.


Schummer M.L.,University of Western Ontario | Petrie S.A.,Long Point Waterfowl | Bailey R.C.,University of Western Ontario | Badzinski S.S.,Long Point Waterfowl | Badzinski S.S.,Environment Canada
Condor | Year: 2012

To identify factors potentially limiting the abundance of ducks at the northern latitude of Lake Ontario, we investigated whether the lipid levels and foraging behavior of sea ducks wintering there were best explained by endogenous or exogenous mechanisms. We used an information-theoretic approach to evaluate if date (14 December-15 March; endogenous mechanism), percentage ice cover of Lake Ontario (long-term exogenous mechanism), short-term ambient temperature (exogenous mechanism), or some combination of these factors best explained variation in lipid reserves and foraging effort of the Bufflehead (Bucephala albeola), Common Goldeneye (B. clangula), and Long-tailed Duck (Clangula hyemalis). In the Long-tailed Duck, date explained lipid declines best, whereas in the Bufflehead and Common Goldeneye lipid reserves varied negatively with percentage ice cover. Conditions at our study site appeared to necessitate foraging because all species foraged, on average, ≥69% of daylight hours, and they increased foraging through the winter and when temperatures decreased. We calculated the number of days until lipid reserves should reach zero (i.e., fasting potential). Fasting potential differed in December, when Buffleheads (11 fasting days) had proportionately more lipid than did Common Goldeneyes (8 days) and Long-tailed Ducks (5 days). By March, the fasting potentials of the three species were similar (4 days), suggesting their survival strategies during similar winter conditions differed. Spatial and temporal modeling of temperature and ice cover with sea duck abundance at Lake Ontario and other Great Lakes may clarify factors that limit sea duck use of the region during winter. © The Cooper Ornithological Society 2012.

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