| Summary: | Although noninvasive genetic surveys play an increasing role in monitoring polar bear population dynamics, genetic methods of identifying age await development. Telomeres––repetitive DNA sequences at chromosome ends––may indicate biological senescence and chronological aging. In some taxa, telomere length has been shown to decline with chronological age, but may vary with tissue, sex, and environmental variation and even within and among individuals of the same age. This thesis evaluates patterns of variation in telomeres as a function of chronological age by i) developing a telomere restriction fragment (TRF) assay in grizzly bears to examine how telomere length varies with age sex, and stress in this taxa and ii) using a quantitative polymerase chain reaction (qPCR) to determine how telomere length varies with tissue, age, sex, and population in harvested polar bears. I also examine iii) Inuit methods of identifying polar bear characteristics to enrich interpretations of these patterns and iv) Inuit perspectives of research and management for insight into long-term community-level monitoring. TRF assays in grizzly bears are able to detect age and sex effects on telomere length, yet these findings are inconclusive. Future work using a larger sample can confirm these relationships. For heart, muscle, and skin salvaged from polar bears, significant differences in telomere length occur among populations and these involve differences in age and sex in muscle and potentially skin. Telomeres will likely serve as a better indicator of biological versus chronological aging. Inuit across Nunavut continue to share methods in identifying sex, age, body size and health of encountered polar bears and their knowledge could inform polar bear surveys. Unfortunately, not all Inuit support current research and management practices, suggesting there is a need to improve collaborative relationships. Including Inuit in monitoring programs can highlight unique, novel methods of monitoring a high profile at-risk species. Ph.D.
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