Measuring wildlife population demographics can be challenging especially in remote areas such as Katmai National Park, Alaska. Here concerns over dramatic changes in number of brown bears (Ursus arctos) seen using Brooks River have led to questions about whether the population has changed. Fortunately, individual bears congregating on salmon spawning streams can be identified by unique physical and behavioral features, which has allowed creation of a long-term, non-invasive record of individual brown bears using Brooks River.We used these bear identification records from 2000-2018 in a mark-recapture framework to estimate age-sex specific survival. We found no changes in survival or relationship between survival and sockeye salmon (Oncorhynchus nerka) escapement. We then used the bear records as a time series of counts in a state-space model to estimate abundance and productivity from 2000-2019. Bear abundance was positively related to sockeye salmon escapement in previous years. However, only some age-sex groups exhibited this relationship. Abundance of breeding females and their cubs was positively related to salmon escapement from the same year, which may indicate they were avoiding Brooks River during years when escapement was low and competition among bears was high. The relationship between annual escapement and productivity measures were not significant, although there were signs that a change in productivity may have occurred.
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