BRS Trevor Price: Evolution of elevational range limits in a changing world

host: Dolph Schluter

zoom recording: https://ubc.zoom.us/rec/share/xKvWSfCH1RGx8BaNNgaOfxV3bLHDW30B8OSzhLuf3Y2uVHdWUkkFwyWc0e7a9q_e.XnZkBUSL9woctk2k

Passcode: Isi2.dda 

Speaker:   Dr. Trevor Price, Professor of Ecology and Evolution, The University of Chicago

Title: Range limits, breeding times, and population size of migratory species in the west Himalaya

Abstract: In mountains in temperate North America, species are tracking climate by moving upslope and by breeding earlier. Earlier breeding accounts for a much greater proportion of climate matching than upslope movements, for reasons that are unclear. Reflecting this pattern, over a 30-year study on a single migratory species in the west Himalaya, elevational shifts have been small and inconsistent, whereas breeding times have differed by as much as 20 days. I show for this species (1) variation in breeding times across years is closely correlated with spring temperatures; (2) this plastic response can affect selection under climate change, through early spring ice storms and late spring heavy rainfall; (3) while breeding season selection may be operating to affect breeding times, habitat availability in the non-breeding season likely plays an overwhelming role in determining population sizes. Ultimately breeding elevational ranges are constrained by habitat, climate, competition, etc., whereas breeding times by constraints on arrival at the breeding grounds, accumulation of resources for breeding, and the disappearance of snow. While substantial elevational shifts are likely to impose fitness costs, alteration of breeding time matches appearance of resources, and advancements, at least under limited climate change, are likely to be positive.