23, 202210. doi: 10.1111/j.1748-7692.2001.tb01009.x, Groesbeck, A. S., Rowell, K., Lepofsky, D., and Salomon, A. K. (2014). Larson, S., Jameson, R., Etnier, M., Jones, T., and Hall, R. (2012). Figure 1 Open in figure viewer PowerPoint Hyg. Sea otter distribution in California (the mainland range) is . % As further range expansion continued, the proportion of the population surveyed by shore and air continued to change, with less survey effort from shore, where detection probability is high, to more survey effort from the air, where detection probability is lower, with potential implications for the interpretation of population trends. Science 282, 473476. This is a fantastic bundle that includes everything you need to know about sea otters across 25 in-depth pages. Relationship between sea otter range expansion and red abalone abundance and size distribution in central California. So using a variety of established study methods radio tracking, veterinary exams, genetic analysis, diet observations this collaborative group of scientists hopes to uncover new knowledge about this population of Californias iconic sea otters a population that hasnt been extensively studied for 15 years. Diseases (Toxoplasma gondii in California and Streptococcus Syndrome in parts of Alaska) also may have a density-dependent effect on local populations (Johnson et al., 2009; Mazzillo et al., 2013; Van Wormer et al., 2014; Counihan et al., 2015; Bartlett et al., 2016). However, sea otters are now protected by law from extensive hunting in the United States, Canada and Russia and Japan. 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). 32, 9971006. Sea otters were hunted extensively for both food and their fur. The Commission continues to follow closely ongoing research into the status and trends of this population, both for the coastal parent population and the translocated population on San Nicolas Island. For many years, the central question driving research in California was why this population was growing so slowly. the documents to your computer and open them with Adobe Reader. (1986a). 6 in southwestern Alaska began to suffer dramatic declines. However, genetic data to assess questions of spatial structuring are limited. doi: 10.1016/B978-0-12-801402-8.00001-9, Larson, S. E., Ralls, K., and Ernest, H. (2015). '3 i]']&lExZ BX"!p+aL6IAnU/DaFLU7 0N$0b/ vqfSs[3fBaISS%;v]I~_?^t.8rjGJ>q8hO]%wGx5DMM-1L/uJ9ttRaw}Z 2Jb K[&x6k >E^[m$1fRcV6q)Y4IDnqpzwhPreoRlY~YoAG.3\0L\HU"!hm(ekpjm LcXT4q. A highly skilled and detail-oriented GIS Technician with a background in Fisheries and Wildlife Sciences and a passion for geospatial technology and data analysis. +(> Xi~PHa3sX#s-mCR*1rFY$Vz!`:_OV 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). Sea otter abundance has been stable in the Kenai Fjords National Park (KEFJ) in southcentral Alaska since at least 2002. While these two examples focus on the recolonization by sea otters of areas without fisheries conflicts, existing long-term monitoring programs, such as GWA, should guide the development of research questions that focus on the effects of recolonization on commercially viable prey species. Considering (1) that the 2000 By the time theMarine Mammal Protection Act (MMPA)was enacted in 1972, the California population had grown from as few as 50 to more than 1,000 individuals (an average annual growth rate of about 5 percent). Intuitively this explanation makes sense, but it took decades for biologists to fully realize how a population functioning at small spatial scales in conjunction with shoreline complexity could explain the relatively slow growth of the California population, which for decades was a source of concern for sea otter researchers and conservation organizations. Critique of the evolutionarily significant unit as a definition for distinct population segments under the US endangered Species act. 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. Incorporating diverse data and realistic complexity into demographic estimation procedures for sea otters. That is, compared to the complex coastline of many areas in Alaska and Canada where remnant or translocated populations could expand in many directions simultaneously (allowing higher population growth rates; Bodkin et al., 1999), the California population could expand only in two directions (north and south). collected in 2010-2012, for sea otters in Southeast Alaska. doi: 10.1371/journal.pone.0082477, Menge, B. Gagne, R. B., Tinker, M. T., Gustafson, K. D., Ralls, K., Larson, S., Tarjan, L. M., et al. How are sea otters using estuarine habitats and prey resources? /Length 9 0 R (1978). sea otters, and then in the early 1990s orcas began eating the sea otters. 65, 75100. Long, sensitive whiskers help the sea otter find prey in dark or murky water, and when underwater, their nostrils and ears close. Where sea otters persist, there is more complexity and productivity in the nearshore marine ecosystem. Infect. What kinds of other animals share the sea otters habitat? Management options to mitigate the effects of sea otters on fisheries do not include reducing sea otter populations through harvests or culls. Due to their thick, soft pelts, sea otters were hunted extensively until an international ban was enforced to prevent their extinction. The sea otter is now an important component of nearshore ecosystems from California to Japan. We will develop an integrative modeling approach that can be used to combine a broad range of data types including behavior, life history, demography, bio-medical, physiology, pathology, parasitology and epidemiology, in order to arrive at a process-based understanding of the factors affecting sea otter populations, and then use this model to provide resource managers with projections of population dynamics and viability under alternative management scenarios, and/or in response to anticipated environmental change. In 2017, the U.S. Navy and the U.S. Imagine that you are on a hunting ship long ago when there were many sea otters. Sea otters versus sea stars as major clam predators: evidence from foraging pits and shell litter. Given the contribution of translocations to the conservation of sea otters by increasing the total numbers of sea otters present today, increasing population connectivity, increasing genetic diversity, and restoring coastal marine ecosystems, we suggest additional translocations be considered to facilitate sea otters recolonization of their historical range. From those sites, we may be able to extrapolate throughout the sea otters range. Tracking sea otters using intraperitoneal radio telemeters is expensive and impractical, especially in remote areas and during the winter, because it often requires personnel to locate individual animals using a radio receiver onboard an aircraft or boat. If the successful translocations during the last half of the 20th century had not occurred, sea otters still might exist only in portions of Russia, Alaska and California. Dean, T. A., and Bodkin, J. L. (2011). White shark (Carcharodon carcharias) related mortality has long been identified as a barrier to the northward expansion of the southern sea otter population in California. (2005b). } !1AQa"q2#BR$3br Geographic variation in sea otters, Enhydra lutris. Sea otters are a keystone predator because they can have significant direct and indirect effects on nearshore ecosystems (Estes and Palmisano, 1974; Estes and Duggins, 1995). Ecol. Foraging behavior and prey of sea otters in a soft- and mixed-sediment benthos in Alaska. 1999). doi: 10.1371/journal.pone.0065435, Springer, A. M., Estes, J. As southern sea otters continue their recovery and expansion into southern and northern reaches of the California coast, they will encounter estuary habitats. EXAMPLES: sea otters living together in Willapa Bay community a group of different populations that live together in a defined area. Otter meat is nutritious and edible and was a valuable source of food for many people for many years. Transmission of toxoplasma: clues from the study of sea otters as sentinels of Toxoplasma gondii flow into the marine environment. In addition to abundance, trends, distribution, and forage energy intake across seasons and years, these replicated surveys provide information on the precision of data achieved by quarterly survey effort. Explore recent publications by USGS authors, Browse all of Pubs Warehouse by publication type and year, Descriptions of US Geological Survey Report Series, Southern (California) sea otter population status and trends at San Nicolas Island, 20172020, Appendix 1. Adult males will establish territories within these areas and vigorously defend them, thereby limiting the number of males in an area (Garshelis et al., 1984). Lia Rudisill - 1 extracted Homeostasis Population Graphs CC.pdf - Name: Period: Kelp Population Trends Graph the data provided on the left to Lia Rudisill - 1 extracted Homeostasis Population Graphs CC.pdf School Watseka Comm High School Course Title HIST2340 2430 Uploaded By JudgeArmadillo241 Pages 5 Ratings 92% (12) Ecology 96, 28772890. A., and VanBlaricom, G. R. (1985). But population recovery has been . In nearly all areas occupied by sea otters, primary production is provided by two pathways. Translocations into historical habitat that had been unoccupied for over a century resulted in populations that grew at or above 20% per year (thought to be the maximum for the species), likely due to abundant prey and little competition among conspecifics (Bodkin et al., 1999). Eventually, remnant and introduced populations increased in abundance and distribution, with some becoming contiguous over spatial scales of thousands of kilometers and comprising tens of thousands of individuals. Sea otters do well in captivity and can be found in many. Conrad, P. A., Kreuder, C., Mazet, J., Dabritz, H., Grigg, M., James, E., et al. When prepared and cooked correctly, it makes a healthy, tasty stew. For example, in central California, where a higher sea otter density is positively associated with higher black abalone density, sea otter predation may have served to reduce poaching impacts by driving black abalone into deep crevice habitat where they were safe from sea otters and poachers (Raimondi et al., 2015). 11, 378383. (1990). Because demand for sea otter artifacts is small, the number of animals killed yearly is modest but increasing [currently averaging more than 1,000 per year in Alaska (USFWS, Anchorage, AK, United States)]. Today, 4,000 km of historically occupied habitat remains unoccupied. Causes of mortality in California sea otters during periods of population growth and decline. The Russia, Alaska, and California populations are each designated as subspecies in part for management purposes, although there are some morphological differences (Wilson et al., 1991). What is the trend between 15-30 years in the sea otter population? Although the FWS declared the translocation a failure, it is quite possible that otter numbers at San Nicolas will continue to grow. Cyclical changes in ocean climate or emerging changes due to climate change (e.g., ocean temperature, acidification) could significantly influence invertebrate populations on which sea otters depend by affecting either transport and recruitment of pelagic larvae (Menge et al., 1997, 2009) or survival and growth of recruits and adults on the benthos (Bodkin et al., 2018). As sea otters reoccupy northern Japan for the first time in over one hundred years, local fishing communities that harvest high-value invertebrates (e.g., uni sea urchin roe sells for $300 kg, and a sea otter can eat 45 kg per day) may place pressure on the government to limit the extent of their reoccupation. Fort Collins, CO: National Park Service. 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. Mussel Bed Sampling: Standard Operating Procedure, v. 1.2, Southwest Alaska Network. Along the California Coast from north of Monterey, South to Point Conception. ) or https:// means youve safely connected to the .gov website. Watson, J. C., and Smith, T. G. (1996). Students should have prior knowledge of food chains, food webs, and keystone species to successfully complete the activity.As students read the news article, they identify predator-prey relationships within the ecosystem and analyze population trends as well as the root cause of the ecosystem collapse. 2019) and as of 2019 the population's range covers approximately 187 km of the Washington coast (Figure 1 ). Fort Collins, CO: National Park Service. doi: 10.1126/science.185.4156.1058, Estes, J. Sequential megafaunal collapse in the North Pacific Ocean: an ongoing legacy of industrial whaling? 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. Bodkin, J. L., Monson, D. H., and Esslinger, G. G. (2007). In addition, new technology is needed to remotely track individual animals at larger spatial and temporal scales with increased accuracy. Killer appetites: Assessing the role of predators in ecological communities. Ser. % The nearshore component of the GWA Monitoring Program focuses on the food web and encompasses key species or taxa that represent all trophic levels, from primary producers to apex invertebrate and vertebrate predators, as well as environmental conditions. Ser. 1982; Jameson et al. The kelp can flourish, providing habitat for many ocean organisms. Group of answer choices True False Flag question: Question 2 Question 22.5, Cory watches as her sister Amanda breaks into a parking meter across the street and starts scooping changeinto her purse. doi: 10.1139/z84-385. (2013). 3, eds A. E. Dizon, S. J. Chivers, and W. F. Perrin (Lawrence, KS: Special publication of the Society of Marine Mammalogy), 197208. Foraging effort (i.e., number of hours per day spent feeding) appears to be related to the status of the population relative to food availability across nearly all the sea otters current range (Estes et al., 1986; Bodkin et al., 2007; Monson and Bowen, 2015; Coletti et al., 2016; Cortez et al., 2016). Their fur is made up of a dense underfur, ranging in color from brown to black, and longer guard hairs. Fig. (2005a). (2012) examined how different management actions (reducing poaching or reducing the sea otter population) would affect population dynamics and found that recovery targets for northern abalone (based on data collected during the period of sea otter absence) were not attainable even when modeled predation by sea otters and poaching of abalone by humans were reduced. He's seen the island's population of sea otters soar over the last handful of years . Sea otter pups are susceptible to predation by bald eagles (Haliaeetus leucocephalus) in areas where they co-occur (Sherrod et al., 1975; Anthony et al., 2008). At the same time, sea otters have helped to restore the ecological functioning of degraded coastal ecosystems by initiating trophic cascades in kelp forests (Estes and Palmisano, 1974; Estes and Duggins, 1995; Watson and Estes, 2011) and estuaries (Hughes et al., 2013), thereby providing valuable ecosystem services by means of these indirect effects. 59, 385401. A sea otters lower jaw is equipped with four incisors. Historic and contemporary status of sea otters in the North Pacific, in Sea Otter Conservation, eds S. E. Larson, J. L. Bodkin, and G. R. VanBlaricom (London: Elsevier), 4361. doi: 10.3354/meps11871. Sea otter population declines have also been observed further east in the Kodiak archipelago. resources and objectives, sea otter population trends, and the power and resolution of the survey data to document changes in abundance. (2008). Am. PLoS One 7:e32205. Since the 1980s, USGS scientists have computed the annual population index and evaluated trends in the southern sea otter. 2 0 obj Changes in Alaskan soft-bottom prey communities along a gradient in sea otter predation. The reproductive system of sea otters is resource defense polygyny (Riedman and Estes, 1990). Federal Register 77. doi: 10.1890/03-0696, Wilmers, C. C., Estes, J. The other is through seasonal blooms in phytoplankton that can occur within an area or be transported to nearshore habitats. Weitzman, B. P. (2013). A. These aquatic members of the weasel family are often seen floating on their backs. Ecol. Documented effects of sea otter reoccupation on marine communities include: (1) the expansion of kelp forests by reducing sea urchin populations (Estes and Palmisano, 1974; Estes and Duggins, 1995; Watson and Estes, 2011); (2) the creation of habitat for kelp settlement through disturbance (Kvitek et al., 1992; Weitzman, 2013; Traiger et al., 2016), (3) changes to epifaunal and infaunal species densities and size distributions (Singh et al., 2013; Weitzman, 2013) and (4) a reduction in commercially valuable invertebrates (Estes and VanBlaricom, 1985; Wendell et al., 1986b; Wendell, 1994; Watson and Smith, 1996; Larson et al., 2013; Hoyt, 2015). Using molecular epidemiology to track Toxoplasma gondii from terrestrial carnivores to marine hosts: implications for public health and conservation. Sea otters now are established (with significant gaps) from northern Japan to southern California. The severity and geographic extent of this decline raise several conservation concerns. Ecol. Alaska Natives can hunt sea otters legally but cannot sell unaltered pelts. (2009). (2015). In addition to their fishery-related impacts, sea otters may come into conflict with recovery efforts for other threatened or endangered species that are part of their natural prey base. the mean tree leaf area per plot that the scientists recorded after running the experiment for 18 months 2,000 cm^2 are the control plots and 1,100 cm^2 for the plots of the beetles Compare the trends in mean tree leaf area per plot for both the plots with the beetles added and the control plots over the 18 months of the experiment What caused the loss of sea otters along the coasts of Washington State and Oregon? You will, 1 out of 1 people found this document helpful, Name: _________________________________________________________, the four graphs located on the last two pages of this document. Gorbics, C. S., and Bodkin, J. L. (2001). 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. 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. B., Staedler, M. M., et al. (2015). Markel, R. W., and Shurin, J. Ecol. Barabash-Nikiforov, I. I. /ColorSpace /DeviceRGB Conserv. Science 360, 10171020. If you ate 25 percent of your body weight daily, as otters do, how many quarter-pound hamburgers would you eat every day? Sea Otters (Enhydra lutris) and Steller Sea Lions (Eumetopias jubatus) in the North Pacific: Evaluating Mortality Patterns and Assessing Population Status at Multiple Time Scales. (USGS). Estes, J. For more information on southern sea otters, see the Commissions 2012 annual report. Ecol. Adult male Alaskan otters weigh 27 to 39 kg, while females weigh 16 to 27 kg. Social organization of sea otters in prince william sound, Alaska. After protection in 1911, these remnant populations expanded across open water up to 50 km to reoccupy neighboring islands (Lensink, 1960). 62, 26482658. Most notable are the nearshore areas: (1) between Northern Japan and throughout the east coast of Sakhalin Island, Russia (1,000 km); (2) between the southern portion of Southeast Alaska and parts of British Columbia (400 km); (3) between central Washington State (the current southern range limit of the northern sea otter) and midway between Monterey Bay and San Francisco Bay, CA, United States (the current northern range limit of the southern sea otter; 1,500 km); and (4) south of Santa Barbara, CA, United States (the current southern range limit of the southern sea otter) and central Baja California (800 km) (Larson and Bodkin, 2015). Look for historical information that might make your narrative more interesting. Although the population decline slowed when nearshore nets were outlawed, growth still progressed slowly (Estes, 1990; Estes et al., 2003). Link will appear as Sea Otter Facts & Worksheets: https://kidskonnect.com - KidsKonnect, August 5, 2018. Both perspectives will benefit from a multi-faceted approach to monitoring not only sea otters, but the nearshore ecosystems they occupy. J. Zool. The southern sea otter has reclaimed only about 13% of its historical range, and its population size is far below its estimated historical population size in California, about 17,000 (though it could be as low as 10,000 or as high as 30,000), a number that does not include the historical populations in Oregon and Baja California. However, these land-based predators likely are not having significant population-level effects. One of the primary threats to the southern sea otter is the risk of an oil spill. 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