In wildlife management, various indices of population status have been proposed or used. Elevated mortality is the most likely reason for this depressed population growth rate; however, the cause or causes of elevated mortality remain unclear, The USGS, Alaska Science Center's Nearshore Marine Ecosystem Research program (https://www.usgs.gov/centers/asc/science/nearshore-marine-ecosystem-research?qt-science_center_objects=0#qt-science_ce, The goal of the Gulf Watch Project (https://gulfwatchalaska.org/monitoring/nearshore-ecosystems/) includes monitoring a wide variety of species inhabiting the nearshore system. Care must be taken to choose indices that reflect integration over sufficient time to avoid variation due to momentary conditions, such as annual weather cycles. 12, Affiliation: U.S. Sea otter numbers have declined in southwestern Alaska over the past 20 years. 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. During the absence of sea otters, many of their prey populations responded to reduced predation through increased densities and sizes. 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. food chains and web's worksheets, coral reef community coloring pages and ocean coral reef coloring page are three main things we want to present to you based on the. that the sea otter population in the Aleutian Islands of Alaska had crashed since 1990. Undertake research that will facilitate and enhance recovery efforts .....57 7. Scientists with, 1. Our findings are consistent with the hypothesis that the decline was caused by increased killer whale predation. 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. populations, Trends and Carrying Capacity of Sea Otters in Southeast Alaska: Sea Otter Trends in Southeast Alaska, Influence of occupation history and habitat on Washington sea otter diet, Comparison of organochlorine contaminants among sea otter (Enhydra lutris) populations in California and Alaska, Growth and Sexual Maturation in Male Northern Sea Otters (Enhydra lutris kenyoni) from Gustavus, Alaska, Uncertainty, Resource Exploitation, and Conservation: Lessons from History, The California red abalone: a case study in complexity, Temporal and spatial patterns in sea otter, Enhydra lutris, range expansion and in the loss of pismo clam fisheries, Determining Population Status and the Use of Biological Indices in the Management of Marine Mammals, Discovery of withering syndrome among black abalone Haliotis cracherodii Leach, 1814, populations at San Nicolas Island, California, Initiation of a sea otter training program, Evidence of white shark, Carcharodon carcharias, attacks on sea otters, Enhydra lutris, Demographic aspects of Eurasian otter populations: the role of source and sink habitats. Biochemical and gene techniques suggested that lingering oil may have contributed to a protracted recovery period for nearshore species. Consistent with these differences, sea otters residing in more recently occupied habitat captured more and larger clams (Saxidomus spp., Protothaca spp., Macoma spp., Mya spp., Clinocardium spp.) Join us every Monday for this new podcast, Reward Offered for Information Regarding Shooting of Bald Eagle, Proposed Incidental Harassment Authorization Available for Public Review and Comment, Happy 60th Birthday to Two Iconic Refuges, ANILCA at 40: Landmark Legislation for an Alaskan Conservation EthicÂ, USFWS Habitat Restoration Staff Part of Team to Receive National Chief's and Under Secretary's Honors Award for Customer Experience, Fish Camp and Family: Cora Demit shares her Alaska Native heritage with visitors to Tetlin Refuge, Remember the Simple Truths: Sylvia Pitka shares Athabascan wisdom with visitors to Alaska. Sea Otter Coloring Sheet - Northern Sea Otter (PDF) ... and utilizing a variety of methodological and analytical tools to understand the causes of biological and ecological trends in sea otter populations, and to predict the ecological consequences of management practices on these populations and their ecosystems. The status of a population is expressed in terms of the population level as a fraction of the mean of natural (undisturbed ecosystem) equilibrium level. Introduction. and other prey, and intertidal clams were more abundant and larger in this area. Ballachey, and G.G. Fact sheet: Sustainability of Coastal Communities and Sea Otters [PDF; 659 KB] Reports. Sea otters have two layers of incredibly dense fur, more than a million fibers per square inch. We have a one-dimensional coastline in California as compared to the two-dimensional coastlines of much of Alaska. Since the middle of the 20th century sea otter populations have been recovering previous habitats, due to natural dispersal and translocations. For example, we work to conduct research examining the impact of sea otter recolonization on commercial and subsistence fisheries in the Southeast Alaska population stock with the University of Alaska, the Alaska Sea Grant program and theÂ, We present our latest research at scientific conferences and publish papers in peer-reviewed journals (seeÂ, We work with graduate students, volunteers and interns on a variety of sea otter management and research projects.Â For more information about theseÂ, We work with Alaska Native Organizations, for example, the. Habitat characteristics are primary determinants of nearshore marine communities. Research on sea otter populations and health can be conducted using different methods, including yearly surveys. For many species, demographic rates change as the population’s status (i.e., relative to prey resources) varies. We hypothesize that the patchy nature of residual oil left in the environment has created a source-sink population dynamic. 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. The translocation and subsequent population growth and range expansion of the northern sea otter (Enhydra lutris kenyoni) in Washington State over the last five decades has created a spatio‐temporal gradient in sea otter occupation time and density, and acts as a natural experiment to quantify how sea otter population status and habitat type influence sea otter diet. They can rub, twist, and pull with a great amount of strength. During most of the early 20th century sea otters were absent from large portions of their habitat in the north Pacific. For the population stocks listed under the Endangered Species Act we produce recovery plans, determine critical habitat and review listing status. The population continued increasing until the mid-1990s, at which time the U.S. 6. 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. 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