For the sake of this exercise, we will ignore E and I for population growth calculations. Sea otters pray on sea urchins and urchins eat kelp. But, despite all of this, it is safe to conclude that overall, the total sea otter population has increased over the 10 year span shown in the graph. 2013). After 1980s, the northern population off southern Alaska has not shown any reduction and it has now become stabilized. Fish & Wildlife Service, Marine Mammals Management Office, October A standardized method to survey sea otters was developed by WERC scientists and put into use in 1982 in California. A separate ground-based survey of the sea otter population at San Nicolas Island was completed earlier (April 15–18). site was created by Lynn Tran at the North Carolina State University, Department Figure J. L. Bodkin, R. J. Jameson, J. The effort to document all stranded southern sea otters continued. Modern efforts in sea otter conservation began in the early 20th century, when the sea otter was nearly extinct due to large-scale commercial hunting. The tail comprises less than a third of the body length. This web Tags: Question 19 . Graph answer choices . One of the main foods of sea otters is sea urchin, which eat … Mating and pupping occur throughout the year, but on average across the range, a peak period of pupping occurs from October to January, with a secondary peak in March and April. Contamination of their fur by oily substances can destroy its insulating properties and lead to hypothermia and death. But sharks are only part of the problem. McKnight, 1973). Which would be least likely to be affected by a density-dependent limiting factor? Ventura, California 93003, Southern Sea Otter (Enhydra lutris nereis) 5-Year Review: Summary and Evaluation, Big Sur Monterey Sea Otter Study Draft Report, Letter to Deputy Assistant Secretary of the Navy Donald Schregardus FSEIS Comments, Final Supplemental EIS on the Translocation of Southern Sea Otters - Volume 1, Final Supplemental EIS on the Translocation of Southern Sea Otters - Volume 2, Final Recovery Plan for the Southern Sea Otter. Examine the graphs in the Lab Book, and describe any trends you observe among kelp, purple sea urchin, and sea otter populations. The state of Alaska re-introduced about four hundred of the animals to Southeast in the 1960’s and they have thrived. Surving otters were used to The … [25] Adult sea otters typically weigh between 14 and 45 kg (31 and 99 lb), making them the heaviest members of the weasel family, but among the smallest marine mammals. The population continued increasing until the mid-1990s, at which time the U.S. Graphs in Figure 2 show growth patterns observed in three sea otter population stocks in the north Pacific resulting from natural range expansion. as the sea otter population decreases, biodiversity increases. Q. Isle Royale is located in Lake Superior. However depleted otter populations throughout Alaska’s Aleutian Islands still remain at 50% of their 1980 abundance. Researchers surveyed sea otter populations along the mainland coast, from Pigeon Point in the north to Gaviota State Park in the south, and also the distinct population at San Nicolas Island in the southern California Bight. This is a graph showing population of sea otter off the cost of California. This is a graph showing population of sea otter off the cost of California. The Monterey Bay Aquarium features a sea otter exhibit and is involved in research and conservation related to this threatened marine species. The southern sea otter population, which once numbered about 16,000 animals, is hovering around 3,000 today. This rapid recolonization exceeds the theoretical maximum population growth rate, suggesting that immigration from outside Glacier Bay is also likely occurring (Esslinger et al. Survey procedures involve counting animals during the "spring survey" -- generally beginning in April and wrapping in June, depending on weather conditions. Females typically give birth to a single pup, with care provided solely by the pup’s mother for the approximately 6 months until weaning. There are also small populations of sea otters in British Columbia, Washington, and California. Recent aerial surveys Otters feed on sea urchins, which in turn keeps them from overgrazing on kelp. 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. In a historic rebound, California sea otters, the frolicking ocean ambassadors of Monterey Bay and Big Sur, have reached their highest population level since 1982, when federal and state officials … Sea otters eat sea urchins, which feed on seaweed. A. Estes (http://biology.usgs.gov/s+t/noframe/s043.htm). Structure Harvester indicated K = 1, and structure output graphs at K = 2 and K = 3 both revealed a clear lack of genetic structure ... Should the northern and southern sea otter populations eventually merge, it would increase the genetic diversity of the CA population, potentially improving health and increasing adaptive potential. of successful translocations. Data from both living and deceased sea otters continues to shed light on sea otter population ecology in different parts of the California coast. It has an unusually large number of otters and, due to both tourism and Þshing, an unusually large number of people. 2 show growth patterns observed in three sea otter population stocks in Although it can walk on land, the sea otter is capable of living exclusively in the oce… 120 seconds . To understand the relationship between the two, Estes needed to find an area that was devoid of otters and see what the kelp forests looked like. C Chemical runoff from a factory kills many crabs and small fish in the area. population is found in coastal waters of Alaska. answer choices . Graph showing regional trends in abundance of sea otters (Enhydra lutris nereis) along the mainland coast, central California, and at San Nicolas Island, southern California ..... 6 4. 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