Survival and population size of the Indo‐Pacific humpback dolphins off the eastern Leizhou Peninsula

• DOI: 10.1111/mms.13156
• Publication Date: 2024-07-06T05:05:14Z
• Authors: Wenzhi Lin; Shenglan Chen; Binshuai Liu; Ruiqiang Zheng; Agathe Serres; Mingli Lin; Mingming Liu; Songhai Li
• Keywords: Indo-Pacific; Peninsula; Mark and recapture

Abstract Indo‐Pacific humpback dolphins form a resident population off the east coast of Leizhou Peninsula (LZP) in South China. The most recent study suggested ~1,500 individuals this area, making one only two populations species exceeding 1,000 individuals. However, demographic information regarding has been lacking since 2012. Using 5‐year (2019–2023) photo‐identification data set, we examined key parameters LZP population, namely apparent survival and size, using multistate capture‐recapture analyses. Annual probabilities (φ) changed over time, fluctuating between 0.942 0.961 for adults, 0.787 0.837 juveniles. Jolly‐Seber model analyses resulted highly comparable noncalf size estimates from 2020 to 2023 ( = 479, SE 28; 2021 458, 29; 2022 481, 27; 446, 31). By reviewing available information, conclude that previously overestimated. time‐dependent survivals seemingly reflect dynamic development anthropogenic disturbance during pandemic period. We propose status should be re‐evaluated, especially postpandemic era when human activities came back “normal” levels.