VOL. SANTA CRUZ, California — The southern sea otter, Enhydra lutris nereis, continues its climb toward recovery, according to the annual count released today by the U.S. Geological Survey and partners. the documents to your computer and open them with Adobe Reader. NO. The spring surveys have traditionally been used to assess population status because they are both consistently higher … 2003 2500 1500 .3 2 U 1000 a 3 Q 0 500 0 1900 1920 1940 1960 1980 2000 Year Figure I. Abundance of California sea otter population from 1911 through 1999. (PDF). Facts about California Sea Otters. A .gov website belongs to an official government organization in the Factors that can influence the count include viewing conditions, abundance and species composition of surface canopy kelp, observer experience, and distribution and movements of the animals. SANTA CRUZ, Calif.— Southern sea otter numbers have declined off the coast of California since their most recent high in 2016. The range-wide index, defined as the 3-year average of combined counts from the mainland range and San Nicolas Island, was 2,962, a decrease of 166 sea otters from the index for the previous year. Click on the links below to explore other sea otter research projects conducted by WERC scientists and partners. Geological Survey3020 State University Drive EastSacramento, California 95819. No single year's survey result is indicative of a population change, however. A standardized method to survey sea otters was developed by WERC scientists and put into use in 1982 in California. WERC scientists conducting long-term research in California and Alaska seek to answer complex ecological questions. They eat about 25% of their body weigh each day to keep their metabolism high. Capture locations for the 1980s sea otter population study.....48 Figure 15. Population status of California sea otters. ... 1994 Data Value (pixels) 2010 Data Value (pixels) 1994-2010 Change (pixels) % Secure .gov websites use HTTPS OSTI.GOV Technical Report: Population status of California sea otters. Fish and Wildlife Service. No data point selected. Fish and Wildlife Service have decided to cancel this year's annual rangewide southern sea otter census. California’s southern sea otter has been listed as a threatened species under the Endangered Species Act since 1977. Share sensitive information only on official, secure websites. Geographic Names Information System (GNIS), Mapping, Remote Sensing, and Geospatial Data, Western Ecological Research Center (WERC), Download Annual Survey Data from 1985 - present (ScienceBase), Population Biology and Behavior of Sea Otters, Annual Southern Sea Otter Survey: Despite Small Population Dip, Species Moves a Step Closer to Recovery, Sea Otter Survey Encouraging, but Comes Up Short of the “Perfect Story”, Numbers Encouraging, but Shark Bites Still Problematic for Sea Otter Recovery, Slowly Swimming Towards Recovery, California’s Sea Otter Numbers Holding Steady, Recovery Slows for California’s Sea Otters, 2012 Survey Shows, Weather Conditions Prevent California Sea Otter Annual Population Survey, California Sea Otters: Population Recovery Continues at Slower Rate. Note: The Spring Survey 3–year running average is the metric the U.S. We work with state, federal, and local partners throughout the species’ range, utilitizing tools and expertise from ecology, chemistry, geography and other disciplines. Interns & Volunteers. ... in otter numbers. The California Sea Otter Stranding Network is part of the USGS effort to monitor southern sea otters (Enhydra lutris nereis) and provide data to the U.S. The 1914 data point is uncertain al- Since 1982, a standardized method has been deployed to survey the sea otter population in California. Sea otter research by scientists at the Santa Cruz Field Station of the USGS Western Ecological Research Center (WERC) focuses on this smallest marine mammal’s population biology and its role as a keystone species in the nearshore marine community. U.S. Geological Survey scientists say the latest 3-year average (2,813 sea otters) was 0.5 percent lower than last year, the first time the trend has been negative since the late 1990s. 19. In addition, the sea otter population size, density, and trajectory are all much greater in Alaska relative to California. Diet: Mating: Sea Otters eat Urchins, abalone, Mussels, Clams, Crabs, snails and about 40 other marine Species. For southern sea otters to be considered for removal from threatened species listing, the population index would have to exceed 3,090 for three consecutive years, according to the threshold established under the Southern Sea Otter Recovery Plan by the U.S. … When sea otters want to rest, they wrap a piece of kelp around their body to hold themselves steady among the rolling waves. The aerial counts are entered directly into a geographic information system-linked database in the aircraft. For 2014, USGS reports the population index as 2,944 (data available online). 200 MARINE MAMMAL SCIENCE. Hughes overlaid the captain’s sea otter counts with historical seagrass coverage data and realised the two graphs were almost perfectly in sync. browser may not display or print as intended. The spread of the California sea otter population provides excellent material for studying the spread of an invading species because the data are not confounded by spread in multiple spatial dimensions. and about normal in the southern half. Survey procedures involve counting animals during the "spring survey" -- generally beginning in April and wrapping in June, depending on weather conditions. Population Historically, sea otters numbered between 150,000 and 300,000 animals throughout the Pacific Rim. 1). Background: The California sea otter population, listed as threatened under the Endangered Species Act, has shown a slow and intermittent rate of recovery over recent years. WERC scientists conduct annual population surveys of the southern sea otter, a federally listed threatened species. The sluggish recovery of the southern sea otter of California, a threatened population on the Endangered Species list, appears to have stalled once again. Part or all of this report is presented in Portable Document Format SANTA CRUZ, Calif. — The recovery of southern sea otters appears to have taken an upturn, according to results from the annual California sea otter survey released by the U.S. Geological Survey today. CALIFORNIA SEA OTTER POPULATION ANNUAL SURVEY – survey history and methodology. ... Data collection on movement patterns, activity budgets and foraging behavior/diet is collected and all data are entered immediately into the wild sea otter database (WSOD). Fish and Wildlife Service, 2003) recommends using the 3-year running average of total counts as the official metric for monitoring trends, thereby reducing the influence of anomalously high Fish and Wildlife Service’s delisting threshold for a second straight year. Download annual survey data from 1985 to present. An estimate of otter population size in Alaska was 98,780 among the three populations in 2013 (USFWS, 2013) with observed annual growth rates in some areas reaching 16–20% (Bodkin et al., 1999; Estes, 1990). California’s Sea Otter Numbers Continue Slow Climb. California Sea Otter (Enhydra lutris nereis) Census Results, Spring 2019 By Brian B. Hatfield, Julie L. Yee, Michael C. Kenner, and Joseph A. Tomoleoni Abstract The 2019 census of southern sea otters (Enhydra lutris nereis), also known as California sea otters, was conducted from early May to early July along the mainland coast of NOTICE: In light of the ongoing COVID-19 pandemic, the USGS and partners at the California Department of Fish and Wildlife, Monterey Bay Aquarium, and the U.S. This population index is what is reported to the U.S. Main resight area in the current Cambria sub-population.....50 Figure 16. The spring 2019 mainland sea otter count began on May 1 and was completed by July 9. Why is California’s threatened sea otter population growing so slowly? ) or https:// means you’ve safely connected to the .gov website. Download the latest version of Adobe Reader, free of charge. Official websites use .gov Fish and Wildlife Service. These data, in conjunction with findings from several more in-depth studies provide the necessary information to assess female reproductive rates and changes in reproductive success of the California sea otter population through time. WERC's sea otter researchers 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. Existing data on the dynamics and demography of the population were synthesized. Monitoring efforts have varied in frequency and type across years. For best results viewing and printing PDF documents, it is recommended that you download Abstract: The GIS shapefile "Range extent of southern sea otters 2017" is a simple polyline representing the geographic distribution of the southern sea otter (Enhydra lutris nereis) in mainland California, based on data collected during the spring 2017 range-wide census. Click on a pin on the map to see more information. A separate ground-based survey of the sea otter population at San Nicolas Island was completed earlier (April 15–18). By 1976 the population contained an estimated 1,789 individuals, but then declined to 1,443 by 1979 and to 1,372 by 1984. Fish and Wildlife Service. Currently the southern sea otter population is estimated at just above 3,000 animals. Data Series Two-person teams use binoculars and spotting scopes to count individuals from accessible stretches of coastline and from fixed-wing aircraft in the remaining areas. Population abundance of the California sea otter has steadily increased through the twentieth century, except for two periods. The 2012 data suggests that California’s sea otter population is continuing its pattern of tepid recovery. California sea otters (5.0%; Riedman and Estes 1990), and reoccupied the full extent of their historical ranges. According to data just released by the California Department of Fish and Wildlife (CDFW) and U.S. Geological Survey (USGS), the three-year average population index this year dropped to 2,962, which is 166 sea otters fewer than the 2018 survey. Fish and Wildlife Service. Full Record; Other Related Research The survey records the total otter numbers, the number of dependent pups, and the number of independents (adults and subadults), observed. 3020 State University Drive East Sacramento, California 95819 The southern sea otter (Enhydra lutris nereis) population at San Nicolas Island, California, has been monitored annually since the translocation of 140 sea otters to the island was completed in 1990. Sea otter habitat is considered to extend offshore from the mean low tide line and out to the 60m isobath: this depth range includes over 99% of sea otter feeding dives, based on dive-depth data from radio tagged sea otters (Tinker et al 2006, 2007). How do sea otters impact near-shore marine food webs? The counts made from shore are plotted on maps and then entered into a spatial database. United States. Santa Cruz, Calif. – After a decade of steady recovery, the southern sea otter — a federally listed threatened species — is in decline for the second year in a row, according to the latest population survey by U.S. Geological Survey researchers. 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. More information Although the California sea otter population is declining, the geographic range of the population continues to expand both to the north and south. PDF documents opened from your For southern sea otters to be considered for removal from threatened species listing, the population index would have to exceed 3,090 for three consecutive years, according to the threshold established under the Southern Sea Otter Recovery Plan by the U.S. During the California Sea Otter Translocation Program Methodology Conclusions & Discussion ... contributed to the unsuccessful recovery efforts of the translocated population. Fish and Wildlife Service’s Southern Sea Otter Recovery Plan recommends using to assess the sea otter population status, thus reducing the influence of anomalously high or low counts from any particular year (USFWS, 2003). SANTA CRUZ, Calif. — The southern sea otter population continues its pattern of tepid recovery, according to the latest population survey led by U.S. Geological Survey, California Department of Fish and Game Office of Spill Prevention and Response and Monterey Bay Aquarium scientists. Yet despite an overall increase in sea otter abundance, sharks have been “taking a bite” out of the portion of the population that could fuel expansion into new areas. Fish and Wildlife Service, and contributes to our understanding of sea otters and nearshore ecosystem health from California to Alaska. It's a … Sea otters play a vital role in the health and stability of the nearshore marine ecosystem as a keystone species Below are news stories associated with this project. Some geographic areas might be reaching equilibrium density for sea otters, while other outlying geographic areas are seeing a rise in otter numbers. Click here to learn more. Population Data Sources California Sea Otter Population By: Danny Hamilton. This graph shows the southern sea otter population trend since 1985, based on the annual data collected by the U.S. Geological Survey. What are the consequences of the rapid sea otter decline in the Aleutian Islands? Data from 1982 onward are counts made during annual spring surveys.Earlier data from counts and estimates using a variety of methods. WERC's sea otter team works with multiple institutions and partners to report, recover, and examine stranded sea otters. According to data just released by the California Department of Fish and Wildlife (CDFW) and U.S. Geological Survey (USGS), the three-year average population index this year dropped to 2,962, 166 sea otters fewer than the 2018 survey. According to data released Friday by the U.S. Geological Survey and partners, the three-year average of the total counts of southern sea otters was down from last year’s high, although it still exceeded the U.S. The historic population of California sea otters was estimated at 16,000 before the fur trade decimated the population, leading to their assumed extinction. Director, Western Ecological Research CenterU.S. Fish and Wildlife Service and Monterey Bay Aquarium with the help of experienced volunteers, cover about 375 miles of California coast, from Half Moon Bay south to Santa Barbara. Spring survey results are used as an indicator of the population trend of California sea otters. Sea otters along the mainland were surveyed from Pillar Point in San Mateo County in the north, to Rincon Point in the south at the Santa Barbara/Ventura County line (fig. WERC's sea otter team and U.S. and Canadian researchers have teamed together to investigate. A lock ( Historically there were about 16,000 southern sea otters, commonly known as California sea otters, that lived from Oregon to Baja, Mexico. Browse the menu, click on the "Data and tools" tab, "News" tab, and "Related" tab to learn about sea otter biology and the annual California sea otter population survey. By con - trast, the sea otter population in California occupies less than 25% of its historic range (USFWS 2015), remains concentrated in the geographic center of … WERC collaborates with other research scientists to conduct annual population surveys of the southern sea otter -- a federally listed threatened species. For southern sea otters to be considered for removal from threatened species listing, the population index would have to exceed 3,090 for three consecutive years, according to the threshold established under the Southern Sea Otter Recovery Plan by the U.S. A CDFW scientist using a telescope to search for sea otters. According to data released Friday by the U.S. Geological Survey, there were 3,186 southern sea otters paddling the Pacific off California. about viewing, downloading, and printing report files can be found here. Overall viewing conditions this year were very good, better than those encountered during the 2018 spring census (View Score = 3.0 this year compared to 2.4 last year, where 0=poor, 1=fair, 2=good, 3=very good, and 4=excellent). To reduce the influence of anomalously high or low counts during any particular year, three-year running averages -- commonly called a "population index" -- of the survey results are also used to assess whether the population is growing or declining. Southern sea otters, also called California sea otters, live in waters along the California coastline, ranging from San Mateo County in the north to Santa Barbara County in the south. Sea Otter Facts. The main objective of the study was to develop a simulation model to facilitate analysis of the risk of oil spills to the threatened California sea otter population. Likewise, California’s sea otter numbers are holding steady against the many forces pushing against their population recovery, according to the latest field survey led by federal, state, aquarium, and university scientists. Capture locations for sea otters for the current sub-populations.....48 Figure 14. Since the 1980s, U.S. Geological Survey scientists have calculated a population index each year for the southern sea otter (Enhydra lutris nereis), a species federally listed as threatened. California Sea Otter Census Results 3 California Sea Otter Census Results Range-Wide Summary The Southern Sea Otter Recovery Plan (U.S. Two-person teams use binoculars and spotting scopes to count individuals (Public domain.). What clues does the sea otter's decline hold for our knowledge of ecosystem and global change? But they were hunted relentlessly in … Sea otters are crucial indicators of the health of our nearshore waters and coastal resources, from kelp forests to fisheries. In fact, a new study released today concludes that California could more than triple its population of southern sea otters, from an estimated 3,000 to nearly 10,000, by repopulating the largest estuary on the coast—the San Francisco Bay. LockA locked padlock The southern sea otter of California, a threatened population on the Endangered Species list, continues to recover, but the rate of recovery appears to have slowed. Once hunted to the brink of extinction for their luxuriant pelts, California sea otters rebounded after protections were put in place in 1911. Hatfield, B.B., Yee, J.L., Kenner, M.C., and Tomoleoni, J.A., 2019, California sea otter (Enhydra lutris nereis) census results, spring 2019: U.S. Geological Survey Data Series 1118, 12 p., https://doi.org/10.3133/ds1118. The information gathered will be used by federal and state wildlife agencies in making decisions about the management of this sea mammal. Sea otter habitat is considered to extend offshore from the mean low tide line and out to the 60m isobath: this depth range includes over 99% of sea otter feeding dives, based on dive-depth data from radio tagged sea otters (Tinker et al 2006, 2007). 1. In addition, instructions on how to report a stranded sea otter are included in this webpage... CALIFORNIA SEA OTTER POPULATION ANNUAL SURVEY DATA (data on ScienceBase). 1118, Explore recent publications by USGS authors, Browse all of Pubs Warehouse by publication type and year, Descriptions of US Geological Survey Report Series. The surveys, conducted cooperatively by scientists of the U.S. Geological Survey, California Department of Fish and Wildlife, U.S. An official website of the United States government. Below are other science projects associated with this project. 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