Indo-Pacific humpback dolphins (Sousa chinensis) in the Moyang River Estuary: The western part of the world's largest population of humpback dolphins

摘要: Information gaps from uninvestigated habitats can hinder population assessments and the efficacy of conservation actions for marine mammals, particularly populations widely distributed species. The full extent occurrence world's largest (putative) Indo‐Pacific humpback dolphins (Sousa chinensis) in Pearl River estuary (PRE) is not known due to a poor understanding western boundary population's range. This information gap basis most critical obstacle assessing status. To determine distribution abundance PRE far portion its range, systematic line‐transect vessel surveys were conducted Moyang (MRE) during 2013–2015. Photo identification cross‐matching individual between different regions also undertaken examine movement patterns. MRE was estimated be 528 individuals (coefficient variation: 28.7–50.2%). Cross‐matching individually identified (present survey area) with those other areas showed that moved frequently across PRE, indicating both comprise single (which renamed PRE–MRE population). this appears waters on eastern side Hailing Island, as never observed further west. Supporting around one‐fifth providing quarter habitat entire population, clearly deserves consideration greater measures. Strengthening management stringent controls over fishing activities establishing protected area core are recommended facilitate better dolphin population.