Can we relate animal migration histories with past changes in climate. Developments in paeoenvironmental studies. Part II


Here I present a combination of paleoenvironmental approaches to examine the centennial- -scale dynamics of the world’s largest colony of the declining and vulnerable Leach’s Storm-petrel (Hydrobates leucorhous) on Baccalieu Island. These data corroborate recent surveys indicating population declines in this species since the 1980s. I also present results from a 10,000 year sediment record tracking the presence of seabirds at Baccalieu Island to show how populations fluctuated in response to the Holocene Thermal Maximum and other climatic anomalies over this time span, including recent population fluctuations coinciding with the two phases of the North Atlantic Oscillation. These results challenge notions that seabird colonies are generally stable in the absence of anthropogenic stressors. I also show new approaches to reconstruct Pacific salmon dynamics based on lake sediment core records, and show how salmon populations in Alaska and British Columbia have varied historically in relation to the warm and cool phases of the Pacific Decadal Oscillation.

Jules Blais
Salle Darcy,
Vendredi, 20 mai, 2022 - 12:00