Monster Seminar Jam - Open it and they will come: examples of salmon colonization from the Pacific Rim
Dr George Pess, Northwest Fisheries Science Center, NOAA Fisheries
Reproductive migration and homing behavior are characteristic and well-studied traits in salmonid fishes (/Salmo, Oncorhynchus, Salvelinus/ and related genera) and common, if perhaps less precise and less well known, in many other fishes as well. The philopatric nature of salmonids is well documented; however, the converse behavior of straying has allowed salmonid populations to colonize new habitats over their evolutionary history. Salmon can disperse and colonize new habitats, or recolonize formerly disconnected habitats quickly, establishing self-sustaining populations. Natal sites are not static because habitat is a shifting mosaic that changes with large-scale natural and anthropogenic disturbances that force dispersal and colonization of new habitats. Why do salmonids stray and what causes the strays to succeed and become colonists in some cases but not others? This presentation investigates how the establishment of self-sustaining salmonid populations in newly opened or reopened habitats is related to the compatibility between specific life history adaptations and geomorphic and ecological conditions that determine stream-habitat characteristics. In this manner, salmon straying can be thought of as active movement to a particular type of place rather than just random dispersal. The hypothesis helps us to focus on four specific factors that can influence successful colonization including: 1) distance from a source population, 2) different habitat preferences among species, 3) local adaptations within species, and 4) competition among and within species. I will present three salmonid colonization examples from across the Pacific Rim including Alaska, British Columbia, and Puget Sound that focus upon the preceding factors.The take home message from my talk is that salmonids simply need an opportunity to colonize newly created or opened habitats in order to successfully establish self-sustaining populations.
Date and Time:
April 1, 2010,
11:00 am - 12:00 pm