(The sea otter is an endangered species). Growth curves demonstrated a significant increase in body mass and body length at age in the 1990s. At the regional scale, the population increased from 13,221 otters in 2003 to 25,584 otters in 2011. In wildlife management, various indices of population status have been proposed or used. Studies in Avian Biology 15:119 – 133. Following a review of the history, utility, and potential of indirect methods for population assessment, we suggest that characteristics of populations, and the individuals within, give a better assessment of ecosystem conditions and relationships than can be achieved through direct measurement. The canopy forming kelps and eelgrass beds found in the nearshore provide primary production and structure to nursery habitats, and can dissipate wave energy, thus reducing coastal erosion, and serve as a carbon “sink” capable of storing substantial amounts of atmospheric carbon dioxide. Objectives of our sea otter population assessment studies include: 1) develop and test methods to identify the degree of population structuring among north Pacific sea otter populations, 2) develop and test techniques to accurately and precisely estimate the status of sea otter populations, 3) develop and test methods to identify cause(s) of change in the status and numeric trends of sea otter populations, 4) develop and test methods to determine the role of density dependent processes in affecting change in sea otter populations, and 5) evaluate the effects of population reductions and translocations on sea otter genetic variability. However, the, Join ResearchGate to discover and stay up-to-date with the latest research from leading experts in, Access scientific knowledge from anywhere. 12, Affiliation: U.S. 1995, Esslinger and Bodkin 2009). 2. Conservation of marine mammals as currently practiced protects populations roughly in proportion to the extent they are reduced. those typical of food-limited populations). The southern sea otter population, which once numbered about 16,000 animals, is hovering around 3,000 today. ForÂ, We monitor health, disease, and patterns of mortality for sea otters in Alaska by; assessing information from ‘healthy’ live-captured animals, assessing information from stranded animals, and conducting forensic necropsies on dead sea otters. We work with Industry (i.e. We provide comments on resource and conservation plans i.e. Although population abundance data are incomplete, there is evidence of increasing, stable and declining sea otter populations in different areas within their range. US Geological Survey conducts these surveys with teams of scientists’ part of the Western Ecological Research Center. Instead, they have an extremely thick coat of fur to keep warm - no animal has thicker fur. They estimated the impact of killer whales on sea otter populations by comparing trends in population size and survival rates of individually marked otters between two adjacent locations on Adak Island: Clam Lagoon and Kuluk Bay. Males (n = 5) and individuals residing in recently occupied habitat (n = 4) spent 0.28-0.30 of their time foraging (6.7-7.2 hr/d), 0.17-0.18 of their time in other diving behaviors (4.1-4.3 hr/d), and 0.53-0.54 of their time resting (12.7-13.0 hr/d). Often data can be collected easily, and they usually reflect current environmental conditions for assessing human-induced changes in the environment. In contrast, females (n = 9) and individuals residing in longer occupied habitat (n = 10) spent 0.40 of their time foraging (9.6 hr/d), 0.08-0.09 of their time in other diving behaviors (1.9-2.2 hr/d), and 0.51-0.52 of their time resting (12.2-12.5 hr/d). Quantitative models of range expansion have rarely been applied to large vertebrates, although such tools could be useful for restoration and management of many threatened but recovering populations. We respond to pollution events, such as boat wrecks and oil spills that may threaten sea otters. • Sea Otter Research o Sea otters are indicators of a healthy ecosystem. for the entire Southeast Alaska stock is 21,798 sea otters. Levels of PCBs in Aleutian and Californian otters are abnormally high when compared with southeast Alaskan otters. However, when we look only at those areas that were most severely affected by the spill, where sea otter mortality approached 90% and where much of the lingering oil has been located. We sit on expert panels to provide the most current information on sea otter management and research and provide peer reviews for reports and publications. This approach requires estimates of: (1) current population level, and (2) carrying capacity of the undisturbed habitat. In this regard, some species serve as indicators of trophic relationships and ecosystem state. The nearshore monitoring program focuses on the nearshore benthic food web in the northern Gulf of Alaska. Sea otter numbers have declined in southwestern Alaska over the past 20 years. Since the middle of the 20th century sea otter populations have been recovering previous habitats, due to natural dispersal and translocations. © 2008-2021 ResearchGate GmbH. In Alaska, there are areas that sea otters can expand into. We collected focal observations of sea otters foraging at sites across the gradient in varying habitat types between 2010 and 2017. Ogden A (1933) Russian sea otter and seal hunting on the California coast. schools, special events, Tribal and community meetings. 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