Biology

Title

Influences of maternal stress on early life characteristics of offspring in threespine stickleback fish

Date of Award

2017

Degree Type

Thesis

Degree Name

Master of Science in Biology

Department

Biology

Chief Instructor

Susan A. Foster

Second Reader

John A. Baker

Third Reader

Philip P. Bergman

Abstract

Feeding performance in early life is predictive of individual survival and reproductive success. Here I take advantage of the broad geographical range inhabited by the threespine stickleback, Gasterosteus aculeatus , to consider how ecological factors might shape early life characteristics over evolutionary time. Additionally, with the application of maternal stressors, I investigate the extent to which offspring growth and behavior are plastically influenced by maternal condition. First generation lab-reared parents were studied, representing populations in British Columbia and Alaska. Gravid females received one of four treatments: acute stressor at ovulation, chronic stressor throughout clutch production, post-ovulatory egg retention (an ecologically relevant challenge) or minimal handling time at ovulation (control). Fry were reared under identical conditions and assayed for growth and feeding performance during the first three weeks post yolk absorption. Fry from the minimal stress treatment differed from those of the three applied stress treatments in terms of growth rate, but not in feeding performance. I discuss how early life traits are affected by maternal stressors, ecological conditions, parental rearing environment, and interactions among these factors.