Bottlenose dolphin (Tursiops truncatus) depredation resulting in larynx strangulation with gill-net parts

Abstract

Cetacean interactions with fishing gear are reported regularly and most frequently involve incidental capture. However, limited records exist related to depredation resulting in fishing gear ingestion. Here, we present cases of depredation resulting from ingestion of gill-net parts and larynx strangulation documented for the first time in a cetacean species. The bottlenose dolphin (Tursiops truncatus) is the only 392 -DURAS GOMERČIĆ ET AL.: LARYNX STRANGULATION IN TURSIOPS 393 resident species in the Adriatic Sea, where small-scale commercial and private fisheries use gill nets throughout the year. A total of 120 dead-stranded bottlenose dolphins found along the Croatian coast of the Adriatic Sea were examined from 1990 to March 2008; 12 of them (10%) were affected by larynx strangulation with gill-net parts. The larynx of all affected animals showed at least one of the following pathological changes: edema, mucosal injury, and hypergranulation. In the majority of cases, it was a chronic condition. Larynx strangulations were found only in adult animals and appeared more often in animals with reduced ability to catch free-swimming prey.

The cisterna chyli and thoracic duct in pigs (Sus scrofa domestica)

“…Eken et al (2002) concluded that the origin and the course of the thoracic duct in cats do not vary except in the manner of termination. Gomercic and Skrtic (1981) described an inverse position of the thoracic duct in a dog, and Duras Gomercic et al (2009) recorded an accessory thoracic duct in the same species. Most of the anatomical variations in the pre-and postcardiac course of the thoracic duct are found in the dog (Grau, 1943;Vollmerhaus, 1981).…”

Marine Anthropogenic Litter

“…In addition to entanglement in derelict fishing gear, other anthropogenic material such as ropes, balloons, plastic bags, sheets and six-pack drink holders can cause entanglement (e.g. Plotkin and Amos 1990;Norman et al 1995;Camphuysen 2001;Matsuoka et al 2005;Gomerčić et al 2009;Votier et al 2011;Moore et al , 2013Rodríguez et al 2013).…”

Effects of fishing gear on bottlenose dolphins (Tursiops truncatus) in the Indian River Lagoon system, Florida

“…2008). The injury has also been documented in gill net interactions in the Adriatic Sea (Gomerčić et al . 2009) and Israel (Levy et al .…”

“…This specific type of injury was first reported from recreational gear interactions in two dolphins from Sarasota Bay, Florida (Gorzelany 1998) and was later noted in another Sarasota case (Wells et al 2008). The injury has also been documented in gill net interactions in the Adriatic Sea (Gomerčić et al 2009) and Israel (Levy et al 2009). Wells et al (2008 notes that all cases in their study area resulted in the death of the animal and suggests that line may become wrapped after a cycle of ingestion and regurgitation.…”