海棲哺乳類の保全?管理のための調査?解析手法繁殖

摘要

Knowledge about the reproductive parameters in cetaceans and pinnipeds is crucial for the conservation and management of the species. There are mainly two types of survey methods for the estimation of reproductive parameters: long-term observation of living individuals and snapshot observation of gonads (testis or ovary) sampled from dead individuals. In this article, we review the following aspects: l)the reproductive characteristics of cetaceans and pinnipeds in the natural history, 2) the anatomical description of reproductive organs, and 3) the survey methods used to estimate reproductive parameters, focusing on the method employed for the direct observation of gonads.