University of Alaska Fairbanks
Reproductive biology of marine mammals
Northern sea otters were extirpated from southeast Alaska in the late 1800's due to extensive hunting by fur traders. They were reintroduced successfully to the area from 1965 to 1969 and the current population continues to grow. Although it is thought that the growth rate is below the level at which a recolonizing population with suitable available habitat should be. In addition, northern southeast Alaska has a lower growth rate than that of southern southeast. Reproduction is one of the possible factors controlling population growth. The goal of this project is to determine the reproductive strategies of sea otters in southeast Alaska to better understand the dynamics of the population. This information will provide a vital component for accurately predicting population growth and can assist in determining what might be driving the lower growth rates and the differences in northern and southern southeast Alaska. Specific objectives of this study include: (1) determine age at first reproduction and age-specific pregnancy rates, (2) determine morphometric changes based on age and reproductive state in both male and female sea otters, and (3) identify endocrine profiles and ovarian morphology to determine the different homeostatic reproductive states for sea otters in southeast Alaska. Alaska native subsistence hunters from throughout southeast Alaska will collect samples from subsistence-hunted sea otters. Sea otters have a significant impact on their prey species and the structure of the entire community in which they live. Determining their reproductive strategies is a critical step in understanding the ecosystem dynamics and creating a more ecosystem-based approach to management. Defining reproductive characteristics of sea otters in southeast Alaska will provide valuable baseline data for modeling the population, assessing the effects of environmental changes, elucidating any differences between the northern and southern populations, and making crucial management and harvest decisions.
Data and Resources
Start Date: 2012/07/01
End Date: 2014/05/31