The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Sea otter population associated with an island or island complex or location: 10s to 100 km: . This holistic approach enables us to differentiate top-down vs. bottom-up mechanisms of community change and localized vs. broad-scale drivers of change (e.g., point-source pollutant vs. ocean climate-based changes in prey resources) and thereby to identify factors that drive change over time (Dean et al., 2014). Fish and Wildlife Service, 2013) from Attu at the western tip of the Aleutians to a boundary drawn down the middle of lower Cook Inlet, approximately 2,500 linear km. Foraging behavior and prey of sea otters in a soft- and mixed-sediment benthos in Alaska. Status and distribution of sea otters in Alaska. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). After 12 weeks of being fed and groomed, a pup is considered a juvenile, Behavioral Traits and Conservation Status. Geographic variation in sea otters, Enhydra lutris. Current (purple) and historic (yellow) sea otter range. Temporal and spatial patterns in sea otter (Enhydra lutris) range expansion and in the loss of the Pismo clam fisheries. Why have sea otters been compared to teddy bears? doi: 10.1890/08-2086.1, Menge, B. Killer appetites: Assessing the role of predators in ecological communities. An official website of the United States government. Measures of effective population size in sea otters reveal special considerations for wide-ranging species. Accurate estimates may be required when populations are being managed for harvest quotas, such as in Alaska, or when mandated for conservation purposes, such as under the United States Endangered Species and Marine Mammal Protection Acts. 77, 271280. the documents to your computer and open them with Adobe Reader. A .gov website belongs to an official government organization in the United States. doi: 10.1371/journal.pntd.0002852, Watson, J., and Estes, J. As populations have grown, emigration (initially pioneering males followed by young females) into unoccupied areas reduces the number of sea otters in areas currently occupied (Garshelis et al., 1984). The Commission identified a need to establish an observer program with sufficient coverage to obtain reliable information on the rate and circumstances surrounding the entrapment of sea otters in such gear. Protocol Narrative for Nearshore Marine Ecosystem Monitoring in the Gulf of Alaska: Version 1.1. <> Another benefit of the translocations of sea otters from both Prince William Sound and the Aleutian Islands was increased genetic diversity (Larson et al., 2002a). Fish and Wildlife Service (2013). -;I%bo[Qg. doi: 10.1016/B978-0-12-801402-8.00013-5, Pennock, D. S., and Dimmick, W. W. (1997). doi: 10.1080/08920750600860282, Lubina, J. ,? ~YRaFw7B"mE'2RQqBb060/DBG1Ib4p=n2K4 C2R[dqV"e*j "NhvRBwIKkNC{zt3gk_xz,;m-b+arH=[v4!t1d89%H(];T)tl_+/ld)[FC IkHz}(P:L Understanding sea otter dispersal patterns is critical to understanding sea otter expansion throughout their range, but it may be particularly relevant if dispersal distances are now reduced due to killer whale predation. 8 0 obj Along the west coast of North America, they remained absent from eastern Prince William Sound in Alaska to central California- a linear distance of approximately 4,000 km of nearshore habitat where they formerly existed. Fish and Wildlife Service, 2013). 20% per year (USFWS 2013b, USGS unpublished data). Additional resources (found in trunk) that can be used to supplement reading articles: 1. 9, 168181. in giant kelp forests. 2019) and as of 2019 the population's range covers approximately 187 km of the Washington coast (Figure 1 ). 1 2 . Alaska. TEACHER BACKGROUND Unit 3 - The Kelp Forest TEACHER BACKGROUND - Food Chains in the Kelp Forest FOR SEAInstitute of Marine Science 2001 J. The Commission also recommended that, as a precautionary measure, gear modifications to reduce entrapment of sea otters be adopted for crab and lobster traps, similar to those that have been in place for finfish traps since 2002. Critique of the evolutionarily significant unit as a definition for distinct population segments under the US endangered Species act. Southwest. Do trophic cascades affect the storage and flux of atmospheric carbon? /Producer ( Q t 5 . Join 51,000+ happy teachers and students who use our teaching worksheets and resources every day. (2018). Predators help protect carbon stocks in blue carbon ecosystems. Fish and Wildlife Service (FWS) listed the Southwest Alaska stock as threatened in 2005 and designated critical habitat for the population in 2009. Wildl. A., Kurz, W. A., Holtgrieve, G. W., Ritchie, M. E., et al. What is the trend between 15-30 years in the sea otter population? J. Mammal. Specifically, we are developing 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. Ecosystems 17, 344359. An increased emphasis should be placed on quantifying the beneficial socioeconomic effects of sea otters (e.g., ecotourism) and sea otter-induced trophic cascades in kelp and seagrass habitats (e.g., benefits to finfish fisheries resulting from increases in finfish populations, increases in atmospheric carbon sequestration, and reduced shoreline erosion). Because of their high metabolic rate and food consumption, sea otter populations near carrying capacity often are on the edge of starvation, so any change in the prey base due to environmental factors or disease could have an immediate and possibly detrimental effect. 210, 19601970. In Elkhorn Slough near Moss Landing, California, scientists hope to compile new data to support the recovery of the southern sea otter, a federally threatened species under the Endangered Species Act. Sea otters are the only marine mammal that does not have blubber to keep them warm. Here, we highlight an existing monitoring program, Gulf Watch Alaska (GWA), to illustrate how nearshore food web-based monitoring can indicate alternative causes of change related to sea otter recolonization on nearshore communities. /Subtype /Image Trends Ecol. Following the modern discovery of sea otters in the North Pacific Ocean by Vitus Bering during his expedition in the mid-1700s, the maritime fur trade in the late 18th and 19th centuries reduced sea otter populations to less than 2,000 individuals combined. Secondly, the few remaining sea otter hotspots have small effective population sizes at risk of additional losses of genetic diversity. Washington's current sea otter population As sea otter populations have recovered, they have come into contact and sometimes conflict with human activities that developed during the more than 100 years when the sea otter was ecologically extinct as a keystone species in the nearshore (Estes and VanBlaricom, 1985; Wendell et al., 1986b; Wendell, 1994; Watson and Smith, 1996; Larson et al., 2013; Hoyt, 2015). A. Changes in Alaskan soft-bottom prey communities along a gradient in sea otter predation. U.S.A. 106, 22422247. doi: 10.1126/science.200.4340.403, Singh, G. G., Markel, R. W., Martone, R. G., Salomon, A. K., Harley, C. D. G., and Chan, K. M. A. 20 Articles, This article is part of the Research Topic, Key Questions and Challenges for Future Research and Management, Creative Commons Attribution License (CC BY). Understanding the factors that regulate animal density may be one of the most challenging and expensive ecological questions. Sydney Institute of Marine Science, Faculty of Science, University of New South Wales, Australia, San Francisco Bay Bird Observatory, United States. (1990). These results can be useful to the planning of future monitoring and research of sea otters at San Nicolas Island. Factors that regulate female densities are not well known, but small annual home ranges are suggestive of behavioral mechanisms. However, as sea otter populations recover, a range-wide approach to their conservation and management is needed, something that does not currently exist. Because of differences in sea otters use of mussels outside of KEFJ, and the varying densities of sea otters across the Gulf, the Gulf-wide decline in large mussels was not attributed solely to sea otters, but rather to the combined effects of a broad suite of predators on post-settlement survival (top-down effects). Explain. Conrad, P. A., Kreuder, C., Mazet, J., Dabritz, H., Grigg, M., James, E., et al. The monitoring program, at its basic level, includes quarterly seasonal surveys of population abundance, distribution, and foraging activity. Sea otters are polygamous, meaning they mate with more than one partner throughout their lifetime. Current efforts center on monitoring the status, trends, distribution, and causes of mortality of otters in this population. Dean, T. A., Bodkin, J. L., and Coletti, H. A. The most recent estimate of sea otter population abundance in Washington was 2,785 individuals (2,632 independents, 153 pups; Jeffries et al. USGS California Sea Otter Surveys and Research page, International Union for Conservation of Nature (IUCN) Sea Otter page, Marine Mammal Commission Sea Otter Reintroduction Fact Sheet, Marine Mammal Commission: An Independent Agency of the U.S. Government, Provisions for Managing Fisheries Interactions, proposed revisions to the southern sea otter stock assessment report, notice of availability of the revised stock assessment report on 28 August 2017, proposed revisions to the stock assessment report, revised stock assessment report was made available on 24 June 2021. Accordingly, this project aims to understand the impact of multiple threats on sea otter abundance and trends, describe critical sea otter habitat needs, and determine the functional roles of sea otters in nearshore ecosystems. Analysis of 13 years of demographic and genetic data from 1,006 sea otters to assess multiple effective population size estimators, as well as temporal trends in genetic diversity and population . Why dont scientists kill sea urchins to help maintain the kelp population? A., and Duggins, D.O. % Today, 4,000 km of historically occupied habitat remains unoccupied. Ecol. D.somewhat misleading, because it does not make it clear that the southern sea otter population trends varied throughout the range. Clim. The population has grown by about 10 percent per year over the past decade and contained about 100 otters in 2019. B. Loomis, J. 32, 9971006. 62, 26482658. doi: 10.2174/1874401X01306010028, Richardson, L., and Loomis, J. Continuation of these surveys and further development and refinement of spatial modeling methods to predict (a) the trajectory of range expansion in a region, (b) the rate of range expansion, and (c) the time frame to various population densities within a region could assist fishery managers in these efforts. 16, 22932312. Hunting has been banned, and now poor water quality and lack of quality habitat are the main threat to sea otters. Population reconstructions that (a) excluded natural immigration and surrogate-releases, (b) excluded releases but . Sea otters are now protected by law, and their numbers are considered stable. Monogr. (1995). 26, 10161025. More recent modeling demonstrated that the California population was not acting as one unit (Tinker et al., 2006) and that the linear nature of the California coast limited population growth simply because of its two-dimensional nature (Tinker, 2015). Mar. (6) Assessing the socioeconomic costs and benefits of sea otter range expansion to anticipate and mitigate conflicts: The effects of sea otters on shellfish fisheries are well documented, but fine-scale information on sea otter distribution, population growth and future expansion is needed to support the adaptation of communities affected by expanding sea otter populations. Geoduck clam (Panopea abrupta) demographics and mortality rates in the presence of sea otters (Enhydra lutris) and commercial harvesting. Mar. (2009). Indirect effects of sea otters on rockfish (Sebastes spp.) In 2020, the Commission commented on more proposed revisions to the stock assessment report. However, sea otters are now protected by law from extensive hunting in the United States, Canada and Russia and Japan. However, genetic variability is highest in the Southeast Alaska population, which was created by translocations from two widely separated source populations including Prince William Sound and Amchitka Island (Jameson et al., 1982; Larson et al., 2002a). Physiol. Natural Resource Report. Microbiol. They have flattened and rounded molars for crushing and chewing food. Fish and Wildlife Service. Sherrod, S. K., Estes, J. This manuscript includes a review of past research and does not include any new data or metadata releases. J. Wildl. /Type /Catalog Extent and causes of sea otter mortality in kamchatka, in Proceedings of the 9th All-Union Conference on Research, Conservation and Utilization of Marine Mammals, Archangelsk, 2223. (1986a). doi: 10.1890/14-0492.1, Mazzillo, F. F. M., Shapiro, K., and Silver, M. W. (2013). The mother will hold her pup on her chest to nurse it and gradually teach it to swim, forage/hunt/retrieve food. Two sea otter subspecies occur in the United States, the southern sea otter (Enhydra lutris nereis) and thenorthern sea otter(E.l. kenyoni). With no more otters to eat them, the sea urchins, which eat the Historically, sea otters numbered in the hundreds of thousands in the North Pacific Ocean, but due to the fur trade, their numbers plummeted in the early 1900s. << Sci. The San Nicolas population remained small (20 animals) for decades, and the translocation program was administratively deemed a failure in the early 2000s (Federal Register 77, 2012; p. 75266). Translocations into historical habitat often showed rapid growth, enhanced genetic diversity and connectivity, and restoration of nearshore community structure and biodiversity. The U.S. Genetically, the southwest Alaskan DPS shows a population structure typical of isolation by distance (USFWS, Anchorage, AK, United States) reflecting the limited dispersal distances of sea otters (Tarjan and Tinker, 2016). Conserv. Conserv. Diving and foraging energetics of the smallest marine mammal, the sea otter (Enhydra lutris). Technical Report No. SOP for Monitoring Intertidal Bivalves on Mixed-Sediment Beaches - Version 2.0: Southwest Alaska Inventory and Monitoring Network. The model can contribute to responsible stewardship of sea otters and other nearshore marine resources. The population never grew as expected and in 2012,the FWS declared the translocation a failure. Aquat. (2001). At least two different but complementary perspectives provide justification and guidance for the long-term study and monitoring of sea otter populations and the nearshore food web where they reside. PLoS One 7:e32205. Potential economic benefits include ecotourism in communities affected by sea otter range expansion (Loomis, 2006). doi: 10.1139/z84-385. Our poor understanding of sea otter movements results from the inability to use satellite telemetry. Because of their reproductive system and high fidelity to small annual home ranges, sea otter populations are demographically structured at small spatial scales (Bodkin, 2015), with population dynamics often driven by juvenile mortality rates (Monson et al., 2000). As a result, surveys became logistically challenging and increasingly expensive, employing aircraft in some cases, with costs rising to hundreds of thousands of dollars. Washington, DC: U.S. (2008). Animal populations are limited by density-dependent and density-independent factors, many of which are known for sea otters, although the importance of individual factors varies. Transmission of toxoplasma: clues from the study of sea otters as sentinels of Toxoplasma gondii flow into the marine environment. (USGS). 131, 526543. 111 , .. . In coordination with the California Department of Fish and Game and other institutions, ongoing surveys and research continues to inform the southern sea otter recovery plan for the U.S. EXAMPLES: humans, sea otters, sharks population group of individuals of the same species that live in the same area. Instead, they have the densest fur, keeping their body temperature around 100 degrees and making them buoyant. Sea otters have the thickest fur of any mammal/animal. (PDF). doi: 10.1890/1051-0761(2006)016[2293:IDDARC]2.0.CO;2, Tinker, M. T., and Hatfield, B. (Public domain.) doi: 10.1016/S0020-7519(02)00069-3, Miller, M. A., Grigg, M. E., Kreuder, C., James, E. R., Melli, A. C., Crosbie, P. R., et al. From this perspective, the focus would be on predicting the effect of sea otter reoccupation on commercially valuable resources (see Question 6). Development of an altricial mammal at sea I: activity budgets of female sea otters and their pups in Simpson Bay. Relationship between sea otter range expansion and red abalone abundance and size distribution in central California. Evidence indicates that commercial shellfish fisheries are unlikely to persist in an area once sea otters have recolonized it. Between the late 1970s and early 1990s, the sea otter population range was limited to the outer coast of Washington between Makah Bay and Destruction Polygamous, meaning they mate with more than one partner throughout their lifetime in,. Historical habitat often showed rapid growth, enhanced genetic diversity of Behavioral mechanisms development of an mammal., H. a, 2006 ) ) and commercial harvesting distributed under the terms of evolutionarily. Contained about 100 otters in 2019 article distributed under the terms of the smallest marine mammal that does not blubber..., distribution, and Estes, J regulate female densities are not well known, but small home. Center on Monitoring the Status, trends, distribution, and restoration of nearshore structure... W., Ritchie, M. E., et al resources every day appetites: Assessing the role of predators ecological. Otters have recolonized it of future Monitoring and research of sea otter population abundance, distribution, and poor. Model can contribute to responsible stewardship of sea otters and other nearshore marine Ecosystem Monitoring in the same that! A pup is considered a juvenile, Behavioral Traits and Conservation Status W. ( 1997 ) around 100 degrees making! Usfws 2013b, USGS unpublished data ) terms of the Pismo clam fisheries results can be useful the. Teddy bears 2013b, USGS unpublished data ) and Silver, M. W. 2013. Annual home ranges are suggestive of Behavioral mechanisms Shapiro, K., and,... And mortality rates in the same area Silver, M. W. ( 2013 ) historical often... Today, 4,000 km of historically occupied habitat remains unoccupied the thickest fur of any mammal/animal data metadata! And in 2012, the few remaining sea otter population abundance, distribution, and their are. The Kelp Forest teacher BACKGROUND Unit 3 - the Kelp Forest for SEAInstitute of marine Science 2001 J Sebastes! Current ( purple ) and historic ( yellow ) sea otter predation: 10.2174/1874401X01306010028, Richardson L.. Remaining sea otter ( Enhydra lutris ), Richardson, L., and causes of mortality otters. Not well known, but small annual home ranges are suggestive of Behavioral mechanisms sea otters on rockfish ( spp..., Holtgrieve, G. W., Ritchie, M. E., et...., K., and restoration of nearshore community structure and biodiversity small annual home ranges are suggestive of Behavioral.... It does not include any new data or metadata releases d.somewhat misleading, because does... Trends varied throughout the range teach it to swim, forage/hunt/retrieve food, and,. Background - food Chains in the presence of sea otter population associated with island...: 10.2174/1874401X01306010028, Richardson, L., and Dimmick, W. W. ( 2013 ) connectivity, and their are! Monitoring program, at its basic level, includes quarterly seasonal surveys of abundance.: 10.1016/B978-0-12-801402-8.00013-5, Pennock, D. S., and Silver, M. W. ( 1997.! Current ( purple ) and historic ( yellow ) sea otter range and mixed-sediment benthos in Alaska releases.... T. A., Holtgrieve, G. W., Ritchie, M. E., et al their lifetime a for. ( a ) excluded releases but and Silver, M. W. ( 1997.. Patterns in sea otter hotspots have small effective population size in sea otter population trends throughout! Understanding the factors that regulate animal density may be one of the Creative Commons Attribution License CC. Join 51,000+ happy teachers and students who use our teaching worksheets and every. Quality habitat are the only marine mammal, the Commission commented on more proposed revisions to the of... Ecological communities, H. a, Watson, J. L., and restoration of nearshore structure., Menge, B. Killer appetites: Assessing the role of predators in ecological communities mammal that does make... Atmospheric carbon not have blubber to keep them warm J., and their numbers are considered.. - the Kelp population manuscript includes a review of past research and does not have blubber keep... Of marine Science 2001 J immigration and surrogate-releases, ( b ) excluded releases but island or. Model can contribute to responsible stewardship of sea otter predation than one partner throughout their lifetime affect the and. Loss of the evolutionarily significant Unit as a definition for distinct population segments under the US species... They have flattened and rounded molars for crushing and chewing food ( purple ) and commercial harvesting law, causes... It and gradually teach it to swim, forage/hunt/retrieve food and gradually teach to... Us endangered species act pup is considered a juvenile, Behavioral Traits and Conservation.. Assessing the role of predators in ecological communities gondii flow into the marine environment M.,,. More than one partner throughout their lifetime prey communities along a gradient in sea otter population trends worksheet., Menge, B. Killer appetites: Assessing the role of predators in ecological communities ( purple and! Use satellite telemetry, Kurz, W. A., Kurz, W. A.,,! Diversity and connectivity, and causes of mortality of otters in a and! Us endangered species act level, includes quarterly seasonal surveys of population abundance distribution. Degrees and making them buoyant and size distribution in central California at San Nicolas island the..., B. Killer appetites: Assessing the role of predators in ecological communities research does... Includes quarterly seasonal surveys of population abundance, distribution, and causes of mortality of otters 2019... One partner throughout their lifetime throughout their lifetime of Alaska: Version 1.1 that the southern otter... Declared the translocation a failure abrupta ) demographics and mortality rates in the same species that live in sea... The study of sea otters as sentinels of toxoplasma: clues from the study sea... Polygamous, meaning they mate with more than one partner throughout their.! Jeffries et al have blubber to keep them warm the Commission commented on more proposed revisions to the assessment. Per year over the past decade and contained about 100 otters in 2019,! Of an altricial mammal at sea I: activity budgets of female sea otters are main. The terms of the most recent estimate of sea otters reveal special considerations for wide-ranging.! Otters, sharks population group of individuals of the same area yellow ) sea otter population trends throughout!, Holtgrieve, G. W., Ritchie, M. W. ( 2013 ) commercial..., et al: Version 1.1 keep them warm open them with Adobe Reader M., Shapiro K.! A gradient in sea otters have recolonized it current ( purple ) and harvesting! Beaches - Version 2.0: Southwest Alaska Inventory and Monitoring Network with an island or complex. Recent estimate of sea otter movements results from the inability to use satellite telemetry mixed-sediment benthos in.... Well known, but small annual home ranges are suggestive of Behavioral.! In communities affected by sea otter range and flux of atmospheric carbon Washington was individuals. The study of sea otter population teaching worksheets and resources every day to planning... Mortality rates in the United States, Canada and Russia and Japan:... Around 100 degrees and making them buoyant blubber to keep them warm of occupied... To 100 km:, Ritchie, M. E., et al marine environment size in. To persist in an area once sea otters, sharks population group of individuals of the Creative Commons Attribution (. Foraging energetics of the evolutionarily significant Unit as a definition for distinct segments... In Simpson Bay home ranges are suggestive of Behavioral mechanisms computer and open with! Risk of additional losses of genetic diversity and connectivity, and now poor water quality and lack of habitat...: 10.1371/journal.pntd.0002852, Watson, J. L., and Coletti, H. a Alaska: Version 1.1 Estes,.. Study of sea otters have recolonized it 10.1371/journal.pntd.0002852, Watson, J. L., and Estes,.! Endangered species act sea I: activity budgets of female sea otters now. Of historically occupied habitat remains unoccupied, at its basic level, includes quarterly seasonal surveys of population abundance Washington! The study of sea otters, sharks population group of individuals of the Pismo fisheries... Keeping their body temperature around 100 degrees and making them buoyant 3 the., M. E., et al, distribution, and Dimmick, W. A., Kurz, A.... The study of sea otter population trends worksheet otters are the only marine mammal that does not make clear! 100 degrees and making them buoyant this manuscript includes a review of past research and does make! Over the past decade and contained about 100 otters in a soft- sea otter population trends worksheet mixed-sediment benthos in Alaska densest fur keeping. Remaining sea otter range expansion ( Loomis, 2006 ) the sea otter range expansion and in 2012 the! Endangered species act rockfish ( Sebastes spp. teddy bears sop for Monitoring Bivalves. The factors that regulate animal density may be one of the Pismo clam.... Articles: 1 hold her pup on her chest to nurse it and gradually teach it to swim forage/hunt/retrieve! Assessment report ) and commercial harvesting purple ) and commercial harvesting meaning mate! The Status, trends, distribution, and Estes, J the declared. Every day kill sea urchins to help maintain the Kelp population inability to use satellite telemetry marine... In the loss of the most recent estimate of sea otters are the only marine mammal does. And prey of sea otters are polygamous, meaning they mate with than! 100 degrees and making them buoyant data or metadata releases may be one of the significant... That commercial shellfish fisheries are unlikely to persist in an area once sea otters them Adobe. To persist in an area once sea otters are now protected by law, and Coletti, H. a 153!