Estimating the rate of increase for the finless porpoise with special attention to predictions for the Inland Sea population in Japan

摘要: The finless porpoise Neophocaena asiaeorientalis inhabits coastal waters and rivers in East Asia is exposed to various human activities. This species listed on the IUCN Red List of Threatened Species due a reduction abundance. Although human-induced mortality can be threat populations, future anthropogenic impacts have not been quantitatively evaluated lack demographic information. Adequate population projections are needed form basis for conservation measures before declines critical levels. We conducted viability analysis Inland Sea, Japan using Leslie matrix model composed age-specific survival fertility rates. described uncertainty annual rate increase (λ) randomly sampled estimates other cetaceans with similar life histories. Plausible median λ ranged from 1.041 (age at first reproduction [AFR] = 7) 1.056 (AFR 5). Future changes extinction probabilities were predicted after combining these (M) available abundance estimates. probability 100 years was 0 %. However, quasi-extinction (<100 individuals) as high 79.0 % years. results also suggest that persistence could achieved small effort reduce mortality.