The Scottish Marine Animal Strandings Scheme (SMASS) completed a necropsy on the whale on Wednesday and found that it had suffered severe injuries and infections as a result of its entanglement.
The young humpback, which measured nine metres long, washed up dead on Skateraw beach, Dunbar last week. It was suspected that it was the same whale that had been spotted tangled in rope and fishing line in the Firth of Forth around a month earlier.
SMASS say the ropes had cut deep into the animal’s tissue and blubber layer, resulting in a severe chronic infection, and that the carcass was riddled with a high number of parasites.
It is thought the ropes had been cutting into the animal’s flesh for several weeks and perhaps months, and that the whale probably died from drowning due to its entanglement.
A spokesperson for SMASS wrote: “A really unfortunate case, this animal had definitely been entangled in rope for several weeks if not months, based on the scarring evident in the skin and underlying tissue.
“The rope had cut deep into the blubber layer, in particular around the pectoral fin where this had caused a severe chronic infection. The animal was in poor body condition, thin, with little free lipid in the blubber layer. It also had a very high parasite burden, most notably of spiny-headed worms, in the intestine. This all built a grim example of the impacts of marine entanglement in these larger baleen whales.
“Once the animal had become entangled, it would have had to spend much more energy dragging rope and any attached gear with it through the water. In this case the rope was stretched tight over the back just behind the head, and this also probably stopped the animal from feeding normally.
“As a result, the whale lost condition, and was therefore more susceptible to the effects of infection and parasitism, which debilitated it further. We found evidence in the lungs that it had eventually drowned, either through exhaustion, or because it became further entangled.”
As well as SMASS, the necropsy of the humpback whale was overseen by a number of organisations, including East Lothian Council Countryside Rangers, who were tasked with moving the animal’s body, the British Divers Marine Life Rescue and crew from Dunbar RNLI Lifeboats.
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