Strand-feeding by coastal bottlenose dolphins (Tursiops truncatus) in the Gulf of Guayaquil, Ecuador

Abstract

De la Parra, R. and Galvan, B. (1987) Observaciones del tursión costero del Pacífico en el sistema Topolobmapo-Ohuira, Sinaloa, con notas acerca del comportamiento, ritmo respiratorio e identificación individual. Pages 137-160 in Memorias, X Reunión Internacional sobre Mamíferos Marinos,

High genetic structure and low mitochondrial diversity in bottlenose dolphins of the Archipelago of Bocas del Toro, Panama: A population at risk?

“…In some of these bottlenose dolphin populations’ males and females have differing home ranges, with females remaining within their natal groups, while males range further and visit different social units (e.g., [ 8 , 20 ]). This fine scale genetic structuring in coastal bottlenose dolphins is evidenced in the remarkable variation of their social structure and feeding behaviors (e.g., [ 21 , 22 , 23 , 24 , 25 ]) across coastal populations. However, the high level of site fidelity, genetic isolation, and low abundance observed in some local populations [ 19 , 26 , 27 ], may impose significant challenges to these animals as they may not be able to respond to rapid changes in their habitat, particularly those caused by human activities (e.g.…”

Guiana dolphins use mangrove margins as a natural barrier to chase fish prey

“…We believe that, the longer and thinner rostrum of adult Guiana dolphins (Simões‐Lopes, 2006), would provide them some advantage in performing foraging tactics using mangroves when compared to the shorter rostrum of calves, allowing adults to use this morphological feature to capture entrapped prey in this specific environment. In the Gulf of Guayaquil, Ecuador, bottlenose dolphins perform the stranding feeding behavior, in which individuals strand in shallow waters (30‐40 cm depth), lying over its right side while displaying the left flipper and waving up its flukes after capturing mullet near mangrove roots (Jimenez & Alava, 2015). Although this behavior does not require any rostrum interaction with the mangrove roots for prey capture, it suggests that other delphinid species can perform foraging tactics close to mangroves when it is advantageous for them.…”

Dorsal fin mark changes for assigning sexes to individual bottlenose dolphins, Tursiops truncatus

“…Knowing the sex of individuals in populations under threat or with high exposure to human impacts can be valuable for conservation efforts, due to intersexual and interindividual differences in temporal and spatial habitat use as well as behaviors (social and foraging). Use of risky foraging strategies, e.g., strand feeding (Fox & Young, 2012;Jiménez & Alava, 2015) and provisioning (Foroughirad & Mann, 2013)…”

“…Knowing the sex of individuals in populations under threat or with high exposure to human impacts can be valuable for conservation efforts, due to intersexual and interindividual differences in temporal and spatial habitat use as well as behaviors (social and foraging). Use of risky foraging strategies, e.g., strand feeding (Fox & Young, 2012; Jiménez & Alava, 2015) and provisioning (Foroughirad & Mann, 2013) or risky foraging habitats, e.g., shallow water lagoons, study population; McGovern et al, 2020 and around mariculture installations (Díaz‐López, 2020; Methion & Díaz López, 2020) by specific sexes or subgroups may further increase their likelihood of negative impacts.…”