This poor animal died of intestinal obstruction.
Leatherbacks eat mainly Jellyfish & as an adaption to such a slippery diet they have backward pointing spikes in their pharynx/upper oesophagus which prevents the Jellyfish slipping out. Unfortunately this also prevents Leatherbacks from regurgitating & spitting out plastic bags which they mistake for Jellyfish.

As the World's Oceans become increasingly polluted with plastic detritus more & more adult Leatherbacks are killed.

Many of the larger adult Leatherbacks move into the North Atlantic to feed on the Jellyfish bloom that occurs each summer. Their travels take them through the Celtic Sea into Scottish & Irish coastal waters. Leatherbacks can be rightly claimed as part of Scotland's fauna -worth remembering next time you throw away that supermarket carrier bag!!!