Monday, 20 May 2013

Industrialized fishing has forced seabirds to change what they eat

The bleached bones of seabirds are telling us a new story about the far-reaching impacts of industrial fisheries on today's oceans. Looking at the isotopes of 250 bones from Hawaiian petrels (Pterodroma sandwichensis), scientists have been able to reconstruct the birds' diets over the last 3,000 years. They found an unmistakable shift from big prey to small prey around 100 years ago, just when large, modern fisheries started scooping up fish at never before seen rates. The dietary shift shows that modern fisheries upended predator and prey relationships even in the ocean ocean and have possibly played a role in the decline of some seabirds.