UW Aquatic & Fishery Sciences Quantitative Seminar

Neala Kendall

UW School of Aquatic & Fishery Sciences

Understanding age and size at maturation of sockeye salmon spawning populations of Bristol Bay, Alaska using probabilistic maturation reaction norms (AKA, How I spent my summer vacation)

Abstract

First I will talk briefly about IIASA and the Young Scientist Summer Program I participated in this past summer. Then, I will present the following: Locally adapted populations may exhibit differences in life history traits, such as age and size at maturation. Environmental variation can lead to life history polymorphisms, including different maturation schedules. Humans can also influence maturation through selective processes such as fishing. Probabilistic maturation reaction norms (PMRNs) aim to disentangle phenotypic plasticity associated with different growth and mortality conditions from potential genetic changes influencing age and size maturation. In this project, I used Bristol Bay sockeye salmon data from 1946-present to calculate PMRNs for length and age at maturation of 17 locally adapted sockeye spawning populations with distinct maturation patterns. Bristol Bay, Alaska is an ideal study site as it has one of the most diverse and abundant sockeye salmon populations in the world and a large commercial gillnet fishery. Our PMRNs can help to elucidate what processes may have caused differences in maturation trends between these populations, and specifically if fisheries induced evolution, due to the differential harvest on the populations, may have impacted these fish.