| Counts of northern elephant seals at rookeries in the Southern California Bight : 1981-2001 - :4528 | National Marine Fisheries Service (NMFS)
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Counts of northern elephant seals at rookeries in the Southern California Bight : 1981-2001
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    "Northern elephant seals (Mirounga angustirostris) at five islands in the Southern California Bight (SCB) were counted during 1981-2001 to monitor status and trends of the population. Counts, stratified by areas within each island, were made during winter breeding season at Santa Barbara Island (1984-2001), San Miguel Island (1985-2001), San Nicolas Island (1988-2001), and Santa Rosa Island (1990-2001) and year-round at San Clemente Island (1981- 2001). At Santa Barbara Island the number of births declined at an average annual rate of -4.8 percent from 1984-2001 (R² = 0.20, slope = -0.05, P = 0.08). At San Clemente Island the number of births increased at an average annual rate of 13.4 percent from 1982-2001 (R² = 0.506, slope = 0.126, P < 0.001). At San Miguel Island the number of births increased at an average annual rate of 5.1 percent from 1985-1994 (R² = 0.981, slope = 0.050, P < 0.001) , but declined at -1.9 percent from 1994-2001 (R² = 0.541, slope = -0.019, P = 0.096). At San Nicolas Island the number of births increased at an average annual rate of 7.3 percent from 1988-2001 (R² = 0.887, slope = 0.070, P < 0.001). At Santa Rosa Island the number of births increased at an average annual rate of 41.8 percent from 1990-2001 (R² = 0.928, slope = 0.349, P < 0.001). Births of northern elephant seals in the SCB increased during 1981-2001. Declines in births which occurred in 1986-87 and 1995-98 were probably due to delayed effects of low pup survival during the 1983 and 1992 El Niño's which resulted in fewer adult females being recruited into the adult population"--Abstract.

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