Sea Lions of the World
نویسندگان
چکیده
Three species of otariids are found in the coastal zone and marine area of Ecuador and the Galápagos Islands. Two species, Galápagos sea lion (Zalophus wollebaeki ) and Galápagos fur seal (Arctocephalus galapagoensis), are endemic to the Galápagos. The South American sea lion (Otaria flavescens) has been recorded several times on the Ecuadorian coast, and even small semi-permanent or resident male groups (~10-30 animals) have frequently been observed in two southern locations (Santa Clara Island and Punta Brava-Salinas). The most recent estimates of Galápagos sea lion and fur seal populations, conducted in November 2001 by the Charles Darwin Foundation around the Galápagos Islands, were 14,00016,000 and 6,000-8,000 animals, respectively. In the last two decades, anthropogenic impacts and natural phenomena have affected both Galápagos pinniped populations. Anthropogenic effects include oil spills (e.g., Jessica), fishery interactions, and illegal hunting (sea lions used for trade in reproductive organs). Natural events such as the 1982-1983 and 1997-1998 El Niños caused large reductions in populations, and diseases are being monitored to try to prevent negative impacts on the islands. Sightings of O. flavescens on the coast of Ecuador have been linked to El Niños since the displacement of this species from Peruvian colonies is Sea Lions of the World 495 Alaska Sea Grant College Program • AK-SG-06-01, 2006
منابع مشابه
Risk factors associated with development of poxvirus lesions in hospitalized California sea lions.
OBJECTIVE To identify risk factors that may predispose California sea lions (Zalophus californianus) to development of cutaneous poxvirus nodules during hospitalization in a rehabilitation center. DESIGN Retrospective case-control study. ANIMALS 90 California sea lions admitted to a rehabilitation center. PROCEDURE Hospital records of 275 stranded California sea lions admitted to the reha...
متن کاملThe role of organochlorines in cancer-associated mortality in California sea lions (Zalophus californianus).
Wild California sea lions (Zalophus californianus) have an unusually high prevalence of neoplasms (18% of stranded dead adults) and high levels of contaminants. The contribution of organochlorine (OC) tissue burdens to the probability of sea lions dying from carcinoma was explored using a logistic regression model. Levels of PCBs and DDTs were determined in blubber of sea lions diagnosed with m...
متن کاملModeling Spatial Dynamics of Steller Sea Lions (Eumetopias jubatus) Using Maximum Likelihood and Bayesian Methods: Evaluating Causes for Population Decline
The timing and extent of the negative population trend in the abundance of the western stock of Steller sea lions has not been geographically uniform. A stochastic metapopulation dynamics model is developed for Steller sea lions. This model allows for geographical differences in factors affecting population processes, and can be parameterized to represent a wide range of hypotheses for the decl...
متن کاملCalifornia Sea Lions Use Dolphins to Locate Food
Aggregations by 3 species of dolphins (the bottlenose dolphin [Tursiops truncatus], the short-beaked common dolphin [Delphinus delphis], and the long-beaked common dolphin [Delphinus capensis]) and California sea lions (Zalophus californianus) were investigated in Santa Monica Bay, California. Groups were followed and observed during 201 boat-based surveys conducted in 1997–2001 documenting tha...
متن کاملEvaluation of circulating eosinophil count and adrenal gland function in California sea lions naturally exposed to domoic acid.
OBJECTIVE To determine the effect of natural exposure to domoic acid (DA) on eosinophil counts and adrenal gland function in California sea lions (Zalophus californianus). DESIGN Cross-sectional prospective study. ANIMALS 39 California sea lions. PROCEDURES Adult female sea lions admitted to a rehabilitation hospital during 2009 were classified into 1 of 3 groups (acute DA toxicosis, chro...
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