Environmental and life-history factors influence multidimensional niche metrics (δ13C, δ15N, Hg)

• Main Authors: 3rd World Seabird Conference 2021, Smith, Reyd
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Underline Science Inc. 2021
• Subjects: Toxicogenomics; Ecosystem; Environmental Engineering; FOS Environmental engineering; Water Pollution; Canada; Kyle; ice algae; Sea ice; Somateria mollissima
• Online Access: https://dx.doi.org/10.48448/4wtf-6x63; https://underline.io/lecture/34545-environmental-and-life-history-factors-influence-multidimensional-niche-metrics

Abstract: Climate change and wide-scale environmental shifts are modifying oceanic patterns, sea ice phenology and abundance, ultimately with implications on food web dynamics. These changes alter the abundance and distribution of primary producers such as ice algae and phytoplankton, with cascading effects at higher trophic levels. Mercury (Hg) is an endocrine disrupting compound that biomagnifies in animals as a result of prey choice. As such, uptake is affected by altered food web dynamics and environmental conditions, which adds an important risk-based dimension in studies of foraging ecology. Multidimensional niche dynamics (δ13C, δ15N, THg; total mercury) were determined among female common eiders (Somateria mollissima) from 10 breeding colonies in areas within North America, Europe, and Russia. Results showed high variation in colony niche dynamics, indicated by niche size and ranges in δ13C, δ15N and THg values in relation to sea-ice presence and colony migratory status. Colonies with higher sea-ice cover during the pre-incubation period had higher median colony δ13C, δ15N and THg. Individuals at migratory colonies had relatively higher THg and δ15N, as well as lower δ13C, suggesting a greater Hg exposure, higher trophic position, and a greater reliance on phytoplankton-based prey. We concluded that variation in multidimensional niche dynamics exists amongst eider colonies which influenced THg concentrations. Further exploration of spatial ecotoxicology and niche dynamics at individual colonies is important to examine the relationships between anthropogenic pressures, foraging behaviour, and the related risks of contaminant exposure at even low concentrations which cumulatively may contribute to negative effects on population stability. Overall, multidimensional niche analysis that incorporates multiple isotopic and contaminant metrics presents an opportunity to help identify populations at risk to rapidly altered food web dynamics. Authors: Reyd Smith¹, David Yurkowski², Kyle Parkinson¹, Jérôme Fort³, Holly Hennin⁴, H. Grant Gilchrist⁴, Oliver Love¹ ¹University of Windsor, ²Fisheries and Oceans Canada, ³Littoral, Environnement et Sociétés (LIENSs), ⁴Environment and Climate Change Canada