Migrating Birds and Underwater Volcanos

In 2013, 3 million Short-tailed shearwaters arrived on the beaches of Australia and promptly died. It is assumed that millions of other birds of this species died at sea. The reason for the mass death remained a mystery until recently. It now appears they were victims of an underwater volcano to the North-east of New Zealand and, possibly, the 'Blob' (https://www.theguardian.com/environment/2021/mar/25/lava-floating-rocks-and-the-blob-the-mystery-behind-the-deaths-of-millions-of-seabirds). The 'Blob' was a marine heatwave which wiped out lots of marine invertebrates and fish. This lack of food was responsible for the deaths of Arctic birds. The 'Blob' could have disrupted the feeding of the Short-tailed shearwaters in the Berent sea, prior to undertaking their energetically-demanding migrations to breed. Necropsies of bird carcasses, revealed they were very underweight and had little muscle mass. Most (97%) had volcanic pumice in their digestive tracts. Pumice is light, so it floats and the desperate shearwaters might have confused it with food. The underwater volcano off New Zealand erupted, as the birds migrated. This generated the pumice. A cruel combination of circumstances.