WARNING: Graphic images of dead whale below
The male juvenile mammal was discovered on Seilebost beach on Thursday morning, when a necropsy was carried out.
A whole range of plastics, including netting, bundles of rope, cups, bags, gloves, packing straps and tubing were discovered inside it, with experts claiming the items had been there for some time.
The Scottish Marine Animal Stranding Scheme (SMASS) says it is investigating why the animal – which it claims “wasn’t in particularly poor condition” – ended up with so much pollution inside it.
SMASS also says the items seemed to have come from both the land and fishing sectors – and could have been swallowed at any point between Norway and the Azores.
In a post on its Facebook page, it added: “Whilst it is certainly plausible that this amount of debris was a factor in its live stranding, we actually couldn’t find evidence that this had impacted or obstructed the intestines.
“This amount of plastic in the stomach is nonetheless horrific, must have compromised digestion, and serves to demonstrate, yet again, the hazards that marine litter and lost or discarded fishing gear can cause to marine life.
“It is also perhaps a good example that this is a global issue caused by a whole host of human activities.”
The group has revealed that by the time it reached the whale, it had been dead for 48 hours and that most of its guts blew out of its side when the necropsy was carried out.
SMASS has thanked members of the coastguard and the Western Isles council disposal team who helped with the necropsy and then bury the whale, which had to be done on site, as there was “no option to move a 20 tonne animal elsewhere”.
Commenting on its Facebook post, one person called the death “absolutely tragic”, adding: “Humans have an awful lot to answer for.”
Another user added: “No matter how much we change our lifestyle now, there will be rubbish in the ocean for many years to come from past generations.
“How can we clean up the deep abysses where marine life goes and we can’t? Man has a lot to answer for.”
Melvin Nicholson said he was there with the coastguard when the “poor, gorgeous creature passed away”.
He said: “I took a couple of photos including the one with a rainbow which I found quite poignant.
“Thank you to everybody concerned who dealt with the aftermath and for returning the beach to its usual pristine condition. Such a shame to see such a beautiful creature succumb in this way though”.