Dear MARMAM community, My colleagues and I are pleased to announce our new publication
Historic population estimates for bottlenose dolphins (Tursiops truncatus) in Aragua, Venezuela, indicate monitoring need Authors: Sergio Cobarrubia-Russo, Shannon Barber-Meyer, Guillermo R. Barreto, and Alimar Molero-Lizarraga Abstract: This study reports historic, capture-mark-recapture survival and abundance estimates of common bottlenose dolphins (Tursiops truncatus) based on photo-identification surveys of coastal Venezuela (along the Aragua coast between Turiamo Bay and Puerto Colombia). We used the most recent data available: dolphins identified by unique dorsal fin marks during wet and dry season surveys conducted from 2004-2008. Dolphin encounter histories were analyzed in the Closed Capture Robust Design framework, with the top model including random movement, constant survival, and capture-recapture probabilities that varied by secondary periods. Survival of marked adults was estimated at 0.99 (95% CI = 0.97-1.00). Population estimates for all adults (marked and unmarked) averaged 31 animals (SD = 13.8), and for all dolphins (all adults and calves), 41 animals (SD = 17.2). Coastal bottlenose dolphins face numerous threats including ship strikes, oil spills, conflict with recreational and industrial fisheries, other negative human interactions, biotoxins, chemicals, noise, freshwater discharge, and coastal development. Further, small populations are, in general, at increased risk due to reduced resiliency and recovery potential when exposed to such threats and to expected environmental and demographic stochasticity. These historic estimates of abundance and survival are critical for establishing a reference state and indicate a need for ongoing monitoring of the small dolphin population while the Aragua coast is still, as-of-yet relatively little-impacted by humans. Should coastal development increase (as is the global trend) and / or environmental catastrophes occur (e.g., harmful algal blooms, hurricanes, oil spills), these historic estimates will be essential for assessing impacts and guiding management and conservation interventions. Our results show year-round dolphin presence and highlight the Venezuelan coastal-oceanic landscape as an area of both future research and conservation importance. Citation: Cobarrubia-Russo, S., S.M. Barber-Meyer, G. Barreto, and A. Molero-Lizarraga. 2021. Historic population estimates for bottlenose dolphins (Tursiops truncatus) in Aragua, Venezuela indicate monitoring need. Aquatic Mammals, 47(1):10-20, DOI: 10.1578/AM.47.1.2021.10. The article is available at: https://www.aquaticmammalsjournal.org/index.php?option=com_content&view=article&id=2119:historic-population-estimates-for-bottlenose-dolphins-tursiops-truncatus-in-aragua-venezuela-indicate-monitoring-need&catid=199&Itemid=326 Sincerely, Shannon Barber-Meyer sbarber-me...@usgs.gov Research Wildlife Biologist USGS Ely, MN 55731
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