Application of multi-species photo-ID database management systems: a user’s perspective

Chan, Stephen C. Y.; Chui, Scott Y. S.; Karczmarski, Leszek

doi:10.1007/s42991-023-00345-8

Cited by 7 publications

(2 citation statements)

References 75 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…All photographs of individuals with distinctiveness D≥1 and image quality Q≥60 were matched and catalogued using the photo-ID data management program DISCOVERY (Gailey and Karczmarski, 2012;Chan et al, 2022c). To minimize any potential bias from mis-identification due to insufficient image quality and/or individual distinctiveness, only high-quality IDphotographs (Q≥70) of highly distinctive individuals (D≥3) were used for all subsequent analyses.…”

Section: Data Collection and Photographic Identificationmentioning

confidence: 99%

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

Lin,

Karczmarski,

Chan

et al. 2024

Front. Mar. Sci.

Self Cite

View full text Add to dashboard Cite

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

show abstract

Section: Data Collection and Photographic Identificationmentioning

confidence: 99%

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

Lin,

Karczmarski,

Chan

et al. 2024

Front. Mar. Sci.

Self Cite

View full text Add to dashboard Cite

show abstract

“…It is also apparent that even though the digital technology is fast advancing and so is in parallel the accuracy and effectiveness of fully automated systems for animal individual identification (e.g., see several examples in Part 1 of this Special Issue, Karczmarski et al 2022a), many research teams continue processing their photo-ID data manually or with assistance of semi-automated systems, and with only limited use of dedicated database management programmes for archiving and managing their photo-ID and associated data (see also Chan et al 2022a). On the other hand, some research teams use automated systems but chose the photo-ID software either arbitrarily or simply by following similar applications in other published studies, with little consideration of the specifics of their own research or the characteristics of the studied species.…”

Section: Editorial Introduction To Partmentioning

confidence: 99%

Individual identification and photographic techniques in mammalian ecological and behavioural research—Part 2: Field studies and applications

et al. 2022

Self Cite

View full text Add to dashboard Cite

Estimating population parameters of African elephants: a photographic mark-recapture application in a South African protected area

Chan¹,

Chui²,

Pretorius³

et al. 2022

Mamm Biol

View full text Add to dashboard Cite

Application of multi-species photo-ID database management systems: a user’s perspective

Cited by 7 publications

References 75 publications

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

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

Individual identification and photographic techniques in mammalian ecological and behavioural research—Part 2: Field studies and applications

Estimating population parameters of African elephants: a photographic mark-recapture application in a South African protected area

Contact Info

Product

Resources

About