Effects of bycatch on the population viability of the narrow-ridged finless porpoises in Ariake Sound and Tachibana Bay, Japan

摘要: The narrow-ridged finless porpoise Neophocaena asiaeorientalis is a coastal ceta - cean that threatened by various human activities. Bycatch mortality particular danger to the population in Ariake Sound and Tachibana Bay, Japan. To evaluate impact of bycatch on viability this population, we simulated changes size over next 100 yr, using Leslie matrix model. simulation trials were repeated for 3 scenarios possible rates. If remains at reported level, estimated annual rate decrease 0.671 3.87%, reduction gen- erations 29.6 86.3%. A ≥30% was predicted almost half trials, even most optimistic scenario. mortalities would pose serious threat population; therefore, should be classified least as 'Vulnerable' according Criterion A4, defined IUCN Red List. Our predictions sensitive estimates. Hence, collection current abundance data promoted order minimize uncertainty risk assessments.