Year of Award

2023

Document Type

Dissertation

Degree Type

Doctor of Philosophy (PhD)

Degree Name

Fish and Wildlife Biology

Department or School/College

W.A. Franke College of Forestry and Conservation

Committee Chair

Paul M. Lukacs

Commitee Members

L. Scott Mills, Joshua J. Millspaugh, Sarah N. Sells, Robert S. Suryan

Keywords

Alaska, integrated model, murrelet, population mismatch, seabird, temporary emigration

Publisher

University of Montana

Abstract

Mechanistic understanding of population dynamics requires linking population change and demographic processes. However, for some species, accurate estimation of population parameters can be difficult owing to their life histories, resulting in reduced or biased inference. Mobile species that are not territorial or use dynamic habitats are susceptible to estimation problems arising from variable exposure to sampling, or temporary emigration, and common approaches to account for it like robust design are not feasible. The outcome is a population mismatch whereby the statistical population, or what was sampled, is not aligned with the biological population, which is what we want to know about.

We explored the use of field and analytical methods to resolve population mismatches for the Kittlitz’s murrelet, an ice-associated seabird of conservation concern. This species has several unusual life history traits that complicate estimation of population dynamics, including dispersed nesting, propensity for nonbreeding, and use of dynamic marine habitats. Therefore, Kittlitz’s murrelet made an excellent study species for developing contemporary approaches to account for temporary emigration when traditional approaches are not possible.

In Chapter 1, we investigated ecological correlates of reproduction of Kittlitz’s murrelets. Our aim was to understand variation in breeding and, more importantly, nonbreeding, which was posited to be the primary source of among-year temporary emigration.

In Chapter 2, we developed an integrated model to estimate abundance of Kittlitz’s murrelets. By combining datasets from boat and telemetry surveys, we accounted for within-year temporary emigration from the statistical population and improved inference about the biological population.

In Chapter 3, we used an integrated population model to estimate population dynamics of Kittlitz’s murrelets, combining multiple datasets into a single analytical framework. By doing so, we were able to estimate annual site fidelity, or among-year temporary emigration, as a latent parameter and reduce unexplained variation in trend, further improving inference about the population of interest.

In Chapter 4, we developed and tested field techniques to aid in direct estimation of annual site fidelity for Kittlitz’s murrelets. Moreover, we advanced our knowledge about this species ecology to improve predictions of its response to projected environmental changes, notably loss of ice habitats.

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© Copyright 2023 Michelle Lynn Kissling