Changing Ecosystems
Globally, natural ecosystems are facing multiple stressors—including climate change—that combine to affect the diversity of ecological services they provide and their ability to withstand further change. To support the conservation, protection, and recovery of Canada’s ecosystems, scientists and decision-makers need to better understand the cascading effects of environmental disturbance. Yet in many northern regions of Canada, including the boreal forest, a lack of studies limits our knowledge of ecosystem change.
To address knowledge gaps and enhance scientific understanding of impacts of climate change and other stressors on ecosystem health, our team leads field-based studies focused on migratory birds, freshwater wetlands, and trophic connections. Although we work primarily in Arctic and boreal regions, to help inform landscape and habitat management at a broader spatial scale, we are also conducting studies in the Canadian Prairies and with international partners.
Phenological responsiveness in shorebirds (Dr. Eveling Tavera Fernández, University of Saskatchewan, Arctic Shorebird Demographics Network, and others): We evaluated changes in timing of nesting for eight Arctic-breeding shorebird species at 18 sites over a 23-year period to test for factors that might determine how birds respond to changes in climate. Adjustments to nesting phenology most closely matched climate variation for species that migrate over long distances. Manuscript published.
Polycyclic aromatic compounds (PACs) in a northern freshwater ecosystem (Jordyn Stalwick and Dr. Philippe Thomas, Environment & Climate Change Canada; Gila Somers and Christopher Cunada, Government of the Northwest Territories; Dr. Kristin Eccles, Health Canada): Although little is known about PACs levels in high latitude freshwater systems, existing data suggest concentrations are either staying constant or increasing. To begin to fill knowledge gaps, we (i) assessed the relative abundance and concentrations of PACs in the Mackenzie River Basin and (ii) tested whether environmental factors (fire, snowmelt, proximity to oil infrastructure) influenced observed concentrations. We showed that concentrations of PACs were relatively low in this system and highlighted the importance of ongoing monitoring to better predict how environmental change will affect PACs levels in the basin. Manuscript published.
Time constraints and goose reproduction (Jordyn Stalwick and Dr. Ray Alisauskas, Environment & Climate Change Canada): To better understand spatial variation in avian reproductive traits, we analyzed Canada and cackling geese breeding data from 16 sites across a broad gradient of latitude. We found that these geese have flexibility in their reproductive strategies that may allow them to accommodate increases in climatic variability. Manuscript published. Blog published.
Legacy lead in freshwater ecosystems (Dr. John Chételat and Frank Baldwin, Environment & Climate Change Canada): Lead shot likely persists in aquatic environments, despite regulations prohibiting it’s use over water. To evaluate the extent to which aquatic birds (especially diving ducks) may be exposed to legacy lead, we are analyzing multiple tissues from harvested waterfowl, including canvasback and lesser scaup.
Arctic-nesting shorebird phylogenetics (Dr. Kees Wanders and Dr. Tamas Székely, University of Bath): To help improve predictions related to impacts of climate change on Arctic-breeding shorebirds, we are collaborating with researchers who are using genetics to identify the population structure and demographic history of key species.
Diet flexibility in lesser scaup (Adam DuBour, M.S., University of Alaska Fairbanks, co-advised with Dr. Mark Lindberg): Adam worked on the Yukon Flats National Wildlife Refuge in interior Alaska to better understand how changes in invertebrate prey resources affect diet selection and growth in lesser scaup ducklings. Defended in 2019. Manuscript submitted.
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Characterizing diets of Arctic shorebirds (Danielle Gerik, M.S., University of Alaska Fairbanks, advised by Dr. J. Lopez): To provide information on resource needs for chicks of Arctic-nesting shorebirds and evaluate potential trophic mismatch, Danielle used eDNA-based techniques to evaluate diet. Defended in 2018.
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Bugs, birds, and fire in Canada’s boreal (Moriah Tanguay, M.Sc., University of Saskatchewan): Working in the Sahtú, Moriah’s thesis was designed to predict impacts of ongoing environmental changes (specifically wildfire) on waterfowl food supplies in northern areas. To help identify key habitats for conservation of boreal waterfowl, Moriah also worked closely with the Canadian Wildlife Service, analyzing waterfowl survey data. Defended in 2021.
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Movement tracking, productivity, and diet of North American Black Terns (Nicholas Shephard, Ph.D. in progress, Advised by Dr. Ann McKellar, Environment & Climate Change Canada): To understand how changes in habitat quality (and consequently food sources) throughout the annual cycle might affect the individual success and survival of adult Black Terns, information on diet is needed. By analyzing and comparing diets of adult Black Terns on the breeding grounds, at staging sites during migration, and on wintering grounds, Nic will quantify differences in diet and trophic levels among adults at different stages of migration and identify potential impacts on productivity .
