Population parameters and heterogeneity in survival rates of Indo-Pacific humpback dolphins in a heavily urbanized coastal region of southeast China: implications for conservation

Frontiers in Marine Science, Год журнала: 2024, Номер 11

Опубликована: Март 20, 2024

The Pearl River Delta (PRD) region on the southeast coast of China is among largest and most populated metropolitan regions world, subjecting Indo-Pacific humpback dolphins ( Sousa chinensis ) inhabiting coastal waters this – apparently population species to intense anthropogenic pressure. In 5-year study (2011-2015), we applied mark-recapture techniques quantify parameters in main body extensive estuarine system River, Lingding Bay (LB), urbanized industrialized part PRD. super-population size was estimated at 928 individuals (95% CI=823-1046), which however over-represents latest number extant animals. Annual estimates fluctuated between 708 750 dolphins, likely reflect accurately latest/current LB. Both overall annual generated by our are considerably lower than previously published abundance estimates. Apparent survival rates were generally low, 0.943 (SE = 0.008, 95% CI 0.929-0.958) 0.815 0.025, 0.766-0.866) for adults juveniles, respectively. conjunction with limited recruitment, they may have led a substantial decline numbers over past two decades. Notably, exhibited heterogeneous apparent across complex seascape Adult that use Hong Kong as their primary habitat 6.2% higher those other parts This difference tripled (19.2%) expression susceptibility environmental and/or stresses. We suggest largely due stressors vary spatially estuary, loss, pollution, declining prey resources appear be threats. Based findings, call strategic conservation planning highest priority given preserve remaining key dolphin habitats waters, mitigate impacts major stressor(s) Guangdong (mainland China) waters. Given encroachment ever-more-intense human activities understanding demographic response underlying mechanisms processes prove instrumental formulation management strategy can secure continuous survival.

Язык: Английский

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Indo-Pacific humpback dolphins face extirpation in Shantou waters

Regional Studies in Marine Science, Год журнала: 2024, Номер 77, С. 103641 - 103641

Опубликована: Июнь 15, 2024

Язык: Английский

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

Marine Mammal Science, Год журнала: 2024, Номер unknown

Опубликована: Июль 5, 2024

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.

Язык: Английский

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Seasonal Distribution and Nature Reserve Planning of Indo-Pacific Humpback Dolphins in the Pearl River Estuary from South China Sea

Global Ecology and Conservation, Год журнала: 2025, Номер unknown, С. e03639 - e03639

Опубликована: Май 1, 2025

Язык: Английский

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A Bayesian framework linking perceived social-ecological effectiveness to stakeholder acceptance in China's Sousa chinensis protected areas

Journal of Environmental Management, Год журнала: 2025, Номер 387, С. 125839 - 125839

Опубликована: Май 23, 2025

Enhancing stakeholder acceptance of marine protected areas (MPAs) is key to fulfilling the 30 × Target, ocean-related Sustainable Development Goals, and UN Decade Ocean Science for (2021-2030). These require MPAs not merely as management interventions, but also social-ecological systems (SESs), where effectiveness complex coupling social ecological through interactions. However, relationships between perceived are often indirect mediated, while traditional models can yield statistical instabilities, risking false conclusions. This article tentatively proposes a partially informative Bayesian posterior framework with three steps five criteria, using theoretically based regulator formula an inverse-Wishart prior in penalized likelihood function stricter estimates. Using field surveys remote sensing data China's Sousa chinensis MPAs, study explores proposed perceptions. estimates improved model convergence, positive definiteness nonsingularity, revealing average 63 % underestimation standard errors. Monte Carlo bootstrapping suggested chain mediation layered mechanisms, whereby related stakeholder-MPA interaction. Practical implications include socially effective conservation, community-based activities, monitoring by scientific community. The more methods may offer preliminary insights broader biological conservation settings practices, subject contextual adaptations.

Язык: Английский

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Distribution shifts in Indo-Pacific humpback dolphins and the co-occurrence of marine heatwaves

Reviews in Fish Biology and Fisheries, Год журнала: 2024, Номер 34(3), С. 1035 - 1050

Опубликована: Апрель 15, 2024

Язык: Английский

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Reproductive dynamics of an inshore delphinid reflect demographic consequences of large-scale coastal constructions

Biological Conservation, Год журнала: 2024, Номер 297, С. 110690 - 110690

Опубликована: Авг. 6, 2024

Язык: Английский

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Responses of Indo-Pacific humpback dolphins (Sousa chinensis) to construction of the Hong Kong–Zhuhai–Macao Bridge

Frontiers in Marine Science, Год журнала: 2024, Номер 11

Опубликована: Ноя. 21, 2024

The location of offshore and coastal marine engineering projects often shows considerable overlap with the foraging breeding grounds mammals. Lingding Bay, located in Chinese Pearl River Delta, is home to world’s largest known population Indo-Pacific humpback dolphins ( Sousa chinensis ). bay also site Hong Kong–Zhuhai–Macao Bridge mega-engineering project. This study assessed responses bridge construction. Data were collected on dolphin sightings by survey vessels following standard line-transect tracks, surveys conducted during pre-construction (2005–2006), construction (2015–2016), post-construction (2020–2021) phases. distribution patterns, density, group sizes, presence calves compared across these three periods. Additionally, range patterns analyzed identification individuals phase. average distance at which sighted from was significantly shorter after completion than Furthermore, density southern region bay—where located—was higher that recorded A noticeable increase sizes may indicate a shift strategy. phase coincided COVID-19 pandemic lockdown period, resultant reduced human activity Bay have influenced other animals some extent. Individual results demonstrated waters near remained an integral habitat for post-construction, as they freely traversed underneath bridge. this hold importance within realm engineering, offering valuable guidance references informed decision-making operational practices associated domains.

Язык: Английский

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Long-lasting social bonds of a habitat-structured delphinid social system

Animal Behaviour, Год журнала: 2024, Номер 219, С. 123025 - 123025

Опубликована: Дек. 16, 2024

Язык: Английский

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