A5025947831- Marine animal studies overview
- Arctic and Antarctic ice dynamics
- Isotope Analysis in Ecology
- Marine and fisheries research
- Cryospheric studies and observations
- Arctic and Russian Policy Studies
- Fish Ecology and Management Studies
- Marine Bivalve and Aquaculture Studies
- Indigenous Studies and Ecology
- Avian ecology and behavior
- Species Distribution and Climate Change
- Mercury impact and mitigation studies
- Wildlife Ecology and Conservation
- Underwater Acoustics Research
- Marine and coastal plant biology
- Geology and Paleoclimatology Research
- Environmental DNA in Biodiversity Studies
- Cephalopods and Marine Biology
- Ocean Acidification Effects and Responses
- Ichthyology and Marine Biology
- Animal Vocal Communication and Behavior
- Animal Behavior and Reproduction
- Medical Imaging Techniques and Applications
- Fish biology, ecology, and behavior
- Data Analysis with R
University of Manitoba
2016-2025
Fisheries and Oceans Canada
2016-2025
University of Winnipeg
2022
University of Windsor
2013-2018
To assess whether demographic declines of Arctic species at the southern limit their range will be gradual or punctuated, we compared large-scale environmental patterns including sea ice dynamics to ringed seal ( Pusa hispida ) reproduction, body condition, recruitment, and stress in Hudson Bay from 2003 2013. Aerial surveys suggested a decline density 1995 2013, with lowest occurring Body condition decreased (cortisol) increased over time relation longer open water periods. The 2010 period...
Climate change is leading to northward shifts in species distributions that altering interspecific interactions at low- and mid-trophic levels. However, little attention has been focused on the effects of redistributions trophic ecology a high trophic-level predator assemblage. Here, during 22-year period (1990-2012) increasing sea temperature (1.0°C) decreasing ice extent (12%) Cumberland Sound, Nunavut, Canada, we examined structure near-apex assemblage before (1990-2002) after (2005-2012)...
Abstract Individual specialization ( IS ), where individuals within populations irrespective of age, sex, and body size are either specialized or generalized in terms resource use, has implications on ecological niches food web structure. Niche degree near‐top trophic‐level marine predators have been little studied polar regions with latitude. We quantified the large‐scale latitudinal variation population‐ individual‐level niche ringed seals Pusa hispida ) beluga whales Delphinapterus leucas...
Abstract Arctic sea ice loss has direct consequences for predators. Climate‐driven distribution shifts of native and invasive prey species may exacerbate these consequences. We assessed potential changes by modelling the base a widely distributed predator (ringed seal; Pusa hispida ) in sentinel area change (Hudson Bay) under high‐ low‐greenhouse gas emission scenarios from 1950 to 2100. All were relatively negligible low‐emission scenario, but high‐emission we projected 50% decline...
Climate-driven alterations of the marine environment are most rapid in Arctic and subarctic regions, including Hudson Bay northern Canada, where declining sea ice, warming surface waters ocean acidification occurring at alarming rates. These changes altering primary production patterns that will ultimately cascade up through food web. Here, we investigated (i) vertical trophic structure Southampton Island ecosystem Bay, (ii) contribution benthic pelagic-derived prey to higher level species,...
Animal movement data are regularly used to infer foraging behaviour and relationships environmental characteristics, often help identify critical habitat. To characterize foraging, models make a set of assumptions rooted in theory, for example, time spent an area increases with higher prey density.We assessed the validity these by associating horizontal diving satellite-telemetered ringed seals (Pusa hispida)-an opportunistic predator-in Hudson Bay, Canada, modelled proxies.Modelled biomass...
State-space models (SSM) are often used for analyzing complex ecological processes that not observed directly, such as marine animal movement. When outliers present in the measurements, special care is needed analysis to obtain reliable location and process estimates. Here we recommend using Laplace approximation combined with automatic differentiation (as implemented novel R package Template Model Builder; TMB) fast fitting of continuous-time multivariate non-Gaussian SSMs. Through Argos...
Management boundaries that define populations or stocks of fish form the basis fisheries planning. In Arctic, decreasing sea ice extent is driving increasing development, highlighting need for ecological data to inform management. Cumberland Sound, southwest Baffin Island, an indigenous community fishery was established in 1987 targeting Greenland halibut (Reinhardtius hippoglossoides) through ice. Following its Sound Boundary (CSMB) designated and a total allowable catch (TAC) assigned...
Polar bears (Ursus maritimus) rely upon Arctic sea ice as a physical habitat. Consequently, conservation assessments of polar identify the ongoing reduction in to represent significant threat their survival. However, additional role potential, indirect, source energy has been overlooked. Here we used highly branched isoprenoid lipid biomarker-based index (H-Print) approach combination with quantitative fatty acid signature analysis show that sympagic (sea ice-associated), rather than...
Abstract Aim Climate change is altering marine ecosystems worldwide and most pronounced in the Arctic. Economic development increasing leading to more disturbances pressures on Arctic wildlife. Identifying areas that support higher levels of predator abundance biodiversity important for implementation targeted conservation measures across Location Primarily Canadian waters but also parts United States, Greenland Russia. Methods We compiled largest data set existing telemetry predators North...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 634:175-197 (2020) - DOI: https://doi.org/10.3354/meps13195 Depth and temperature preference of anadromous Arctic char Salvelinus alpinus in Kitikmeot Sea, a shallow low-salinity area Canadian Les N. Harris1,*, David J. Yurkowski1,2, Matthew H. Gilbert3, Brent G. T. Else4, Patrick Duke4, Mohamed M. Ahmed4,...
Abstract Sea ice primary production is considered a valuable energy source for Arctic marine food webs, yet the extent remains unclear through existing methods. Here we quantify algal carbon signatures using unique lipid biomarkers in over 2300 samples from 155 species including invertebrates, fish, seabirds, and mammals collected across shelves. Ice were present within 96% of organisms investigated, year-round January to December, suggesting continuous utilization this resource despite its...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 562:237-250 (2016) - DOI: https://doi.org/10.3354/meps11950 Influence of sea ice phenology on movement ecology ringed seals across their latitudinal range David J. Yurkowski1,*, Christina A. D. Semeniuk1, Lois Harwood2, Aqqalu Rosing-Asvid3, Rune Dietz4, Tanya M. Brown5, Sydney Clackett1, Alice...
A large reef manta ray (Manta alfredi) aggregation has been observed off the north Sudanese Red Sea coast since 1950s. Sightings have predominantly within boundaries of a marine protected area (MPA), which was designated UNESCO World Heritage Site in July 2016. Contrasting economic development trajectories proposed for (small-scale ecotourism and large-scale island development). To examine space-use, Wildlife Computers® SPOT 5 tags were secured to three rays. two-state switching Bayesian...
Abstract Cambridge Bay, Nunavut, hosts Canada’s largest Arctic Char Salvelinus alpinus commercial fishery with waterbody-specific quotas managed under one Integrated Fisheries Management Plan that emphasizes ecosystem-based management and the need to understand bycatch in fishery. Bycatch reporting fishery, however, remains deficient. In this study, we report on fish, invertebrate, marine mammal recorded logbooks from 2012-2018 at two waterbodies fished using weirs (Halokvik, Jayko) gillnets...
Satellite-linked time-depth recorders were deployed on 17 ringed seals in early summer 1999, 2000, and 2010, near the Inuvialuit community of Ulukhaktok, Northwest Territories, Canada. The main objective was to investigate movements diving behaviour Prince Albert Sound (PAS) eastern Amundsen Gulf (EAG) regions relation season, sex, age-class. Tags performed well 16 tagged seals, with average tracking periods 256 d (SD 69, range: 134 – 352). Adult subadult traveled considerable distances...
The Arctic is changing rapidly due to climate change, which allowing unprecedented levels of vessel traffic transit the region. Vessel can negatively affect marine wildlife in a number ways, particularly areas where vessels overlap with high concentrations ecologically important species, and significance these impacts are increased concern when also culturally important. Tallurutiup Imanga National Marine Conservation Area, located Lancaster Sound, Nunavut, Canada, at eastern entrance...
Abstract Aim Identify hotspots and areas of high species richness for Arctic marine mammals. Location Circumpolar Arctic. Methods A total 2115 biologging devices were deployed on mammals from 13 in the 2005 to 2019. Getis‐Ord G i * calculated based number individuals grid cells each phylogenetic groups (nine pinnipeds, three cetaceans, all species) with identified summer (Jun‐Nov), winter (Dec‐May) entire year. Seasonal habitat differences among species’ investigated using Principal...
Abstract Narwhal and beluga whales are important species to Arctic ecosystems, including subsistence hunting by Inuit, little is understood about their mating ecology. Reproductive tract metrics vary across in relation strategy, have been used infer tracts from narwhal were collected between 1997 2008 five stocks two the Canadian Arctic. Tract length for males females, relative testes mass males, tusk male measured. We assessed variation species, body size, stock, maturity, season....