Otters do not have blubber like other marine mammals, such as whales. Establish information management and retrieval systems .....55 5. Abstract. Sea otter populations in Southeast Alaska, USA, have increased dramatically from just over 400 translocated animals in the late 1960s to >8,000 by 2003. Trends in Sea Otter Population Abundance in Western Prince William Sound, Alaska: Progress Toward Recovery Following the 1989 Exxon Valdez Oil Spill By J.L. schools, special events, Tribal and community meetings. As mammals, sea otters have hair and feed their babies milk. We fit models using the age distributions of both living and dying animals and estimates of sea otter population size to predict the number of sea otters in the hypothesized sink population and the number lost to this sink due to chronic exposure to residual oil. Despite difficulties with implementation, no alternatives have arisen to replace this paradigm for marine mammal conservation. During most of the 20th century, through protection and reintroduction, sea otter populations generally increased in abundance and distribution such that most of their range in Alaska, with the exception of southeast Alaska, was occupied by 2000. The student measured the kelp abundance at 4 different sites, then spent a day at each site and marked whether otters were present or absent every 5 minutes during daylight hours. Protect habitats used by sea otters .....55 4. 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. We provide comments on resource and conservation plans i.e. animals caught during 2004, when the population density was very low, were precluded by a small sample size and consequently only examined incidentally to the main growth curves. Although population abundance data are incomplete, there is evidence of increasing, stable and declining sea otter populations in different areas within their range. Our approach provides guidance for the acquisition of further data and a means of forecasting the consequence of specific management actions. are a salient example of a keystone species exerting top‐down control on ecosystem community structure. 13 No. Similarly, we observed higher than expected energy intake rates ranging from 21.20 kcal/min to 27.71 kcal/min for sea otters foraging south of the core area, compared to the typical 12-21 kcal/min. 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. Behaviors were classified as foraging (diving to the bottom), other diving (traveling, grooming, interacting), and nondiving (assumed resting). However, the, Join ResearchGate to discover and stay up-to-date with the latest research from leading experts in, Access scientific knowledge from anywhere. The fundamental force behind population change is the balance between age-specific survival and reproductive rates. Often data can be collected easily, and they usually reflect current environmental conditions for assessing human-induced changes in the environment. The source of PCBs to the Aleutian Islands remains unclear and vital to understanding the potential impacts to sea otters. Underneath the guard hair is another layer of fur that stays completely dry. Using demography and movement behavior to predict range expansion of the Southern Sea Otter, Activity Budgets Derived From Time‐Depth Recorders in a Diving Mammal. 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