Pescador Island Bait Ball

Pescador Island is an island located in the Tañon Strait, a few kilometres from the western coast of the island of Cebu in the Philippines.

The waters of Moalboal Marine Park are extremely deep and harbor some of the highest levels of biodiversity in the world including 2,500 species of fish.

Maldives Bait Shower

More Bait Ball Mayhem

Another bait ball blitz courtesy of the BBC's Blue Planet.

Now in 3-D: The shape of krill and fish schools

An interesting story in Scientific American, where I found the link to the video, about the geometry of bait balls.

When the fish are all riled up in the presence of a predator, they do form these dense bait balls as each fish scrambles to get to the center to hide. This centripetal motion literally forms a sphere: the shape that has the most interior volume and keeps the fewest number of fish on the surface and thus more vulnerable to predators. Of course, this is not the shape that a shoal traveling casually forms. Instead, we have "circles, discs, ellipses, triangles, wedges, crescents, and lines" (McFarland and Moss 1967). Thus predation alone cannot be the only factor shaping shoals; is there another central factor and what is it?

LINK

Bait Balling Sailfish

In the Shadow of the Bait Ball

It's been a while since we've done a bait ball post.