Seabirds of Newfoundland and Labrador: Using stable isotope techniques to investigate changing trophic position over ~120 years, and examining their influence on terrestrial coastal ecosystems ...

• Main Author: Morrissey, Molly M.
• Format: Text
• Language: English
• Published: Memorial University of Newfoundland 2023
• Subjects: Alca torda; Atlantic puffin; Common Murre; fratercula; Fratercula arctica; Newfoundland; North West Atlantic; Razorbill; Uria aalge; uria
• Online Access: https://dx.doi.org/10.48336/aaq6-5932; https://research.library.mun.ca/16136/

Seabirds breeding around Newfoundland and Labrador (NL) are facing multiple destabilizing trends in recent decades, including major fisheries collapses and increasingly erratic temperature cycling in the north-west Atlantic Ocean. Evidence suggests that these seabirds are foraging on poorer quality prey, which could have consequences for terrestrial ecosystems near seabird colonies, as seabirds are one of the major nutrient biovectors in the world. In this thesis I employ stable isotope analysis (SIA) to investigate temporal and spatial questions related to NL seabird ecology. In the first research chapter, I use stable isotopes of nitrogen (δ15N), as well as amino-acid specific stable isotopes of nitrogen (δ15NAA), as a proxy for seabird trophic level. I measured δ15N values in breast feathers of four common breeding NL seabirds (Atlantic puffin Fratercula arctica, Leach’s storm-petrel Hydrobates leucorhous, common murre Uria aalge, and razorbill Alca torda) over a period of 120+ years (1899-2021). The ...