Age-specific recruitment and natality of California sea lions at San Miguel Island, California

摘要: We conducted a 15 yr mark-resight study of branded California sea lions (Zalophus californianus) at San Miguel Island, California, to estimate age-specific recruitment and natality the population. used Schwarz Stobo model sighting, survival, recruitment, timing births, abundance, from sighting histories 1,276 parous females. The advantage this approach was that reproductive status females did not have be known for all age. Probability into population began age 3 or 4, peaked between ages 5 7, slowly declined. Age-specific similar 4–16 but declined after 17, suggesting senescence occurs in older average annual 0.77 (SE = 0.03); 0.56 0.10) 17–21 Natality both classes reduced during El Nino conditions by 24% 34%, respectively. In addition reducing natality, events may result delay if experience before they turn 4