Spatial patterns of shark-inflicted injuries on coastal bottlenose dolphins in the Mesoamerican Reef System

Sublethal Injuries and Physical Abnormalities in Maldives Manta Rays, Mobula alfredi and Mobula birostris

“…Studies investigating shark bite scarring frequencies in dolphins (e.g., Tursiops spp.) have suggested predation pressure may be influenced by the availability of other shark prey (Heithaus, 2001a;Smith et al, 2018), spatial and temporal overlap of dolphins and sharks (Melillo-Sweeting et al, 2021), similar habitat selection (e.g., the use of sheltered semi-enclosed waters) (Sprogis et al, 2018), reduced fishing pressure for large sharks (Castelblanco-Martínez et al, 2021), or differences in dolphin and shark species or sizes, and the resulting probability of a lethal shark encounter (Heithaus, 2001b;Heithaus et al, 2017;Wilkinson et al, 2017).…”

Lords of the Rings: Mud ring feeding by bottlenose dolphins in a Caribbean estuary revealed from sea, air, and space

“…Coastal bottlenose dolphins are the only dolphin species known to occur in Chetumal‐Corozal Bay and throughout the diverse habitats along the coast of Belize, including its bays, rivers, lagoons, around mangrove cayes, and in offshore atolls (Ramos et al, 2016; Castelblanco‐Martínez et al, 2021). The use of mud ring feeding by bottlenose dolphins was confirmed through direct observations of dolphin foraging activity or inferred through the detection of circular mud ring trails (i.e., circular seabed scars left as the byproduct of ring‐making) in the substrate in aerial and VHR satellite imagery.…”

Evidence of interactions between sharks and Indo‐Pacific humpback dolphins (Sousa chinensis) in the northern South China Sea

“…Several widely distributed species including bull sharks (Carcharhinus leucas), tiger sharks (Galedocerdo cuvier), sixgill sharks (Hexanchus griseus), and white sharks (Carcharodon carcharias) have been documented in the South China Sea (Arai & Azri, 2019;Compagno, 1997;Lam & Sadovy de Mitcheson, 2011;Talaue-McManus, 2000). These species have been suggested to be responsible for most shark-inflicted injuries on dolphins in other locations (Castelblanco-Martínez et al, 2021, Corkeron et al, 1987Heithaus et al, 2001aHeithaus et al, , 2006Smith et al, 2018), but except for the Taiwan population, sharkdolphin interactions in the South China Sea have not yet been assessed. In the present study, we investigated the occurrence of shark-inflicted injuries on Indo-Pacific humpback dolphins from three locations in the northern South China Sea, based on a long-term photo-identification (photo-ID) survey effort, to evaluate the potential interactions between dolphins and sharks in these areas.…”

“…The top jaw of the tiger shark leaves a blunt scar with minimal curvature, whereas other sharks inflict more rounded scars. Shark bites that were not likely caused by a tiger shark were categorized as "other shark species" as it could not be determined which shark species inflicted the injury; though, bull sharks are present in the area and are a known dolphin predator in other regions (e.g., Castelblanco-Martínez et al, 2021, Corkeron et al, 1987Heithaus et al, 2006;2001a;Smith et al, 2018).…”

“…T A B L E 1 Features of injured individuals, characteristics of injuries, and potentially responsible shark species. (Arai & Azri, 2019;Chen et al, 2014;Compagno, 1997;Lam & Sadovy de Mitcheson, 2011;Talaue-McManus, 2000) that are known to prey on dolphins in other locations (Castelblanco-Martínez et al, 2021, Corkeron et al, 1987Heithaus et al, 2001aHeithaus et al, , 2006Smith et al, 2018). However, intense shark fishing has caused a decrease in the northern South China Sea shark populations.…”