Remains of endangered Hawaiian petrels – both ancient and modern – show how drastically today’s open seas fish menu has changed.

A research team, led by Michigan State University and Smithsonian Institution scientists, analyzed the bones of Hawaiian petrels – birds that spend the majority of their lives foraging the open waters of the Pacific. They found that the substantial change in petrels’ eating habits, eating prey that are lower rather than higher in the food chain, coincides with the growth of industrialized fishing.

The birds’ dramatic shift in diet, shown in the current issue of the Proceedings of the National Academy of Sciences, leaves scientists pondering the fate of petrels as well as wondering how many other species face similar challenges.

‘Our bone record is alarming because it suggests that open-ocean food webs are changing on a large scale due to human influence,