Gotham Whale, Inc. wrote -
Gotham Whale is a 501 c 3 not-for- profit corporation working to study, advocate for, and educate about the whales and marine mammals of New York City, through Citizen Science.
When we observe humpback whales feeding on menhaden, we notice that the whales seem to know exactly where the "bait balls" are located. They do not have echolocation (only toothed whales have that capacity) - they probably don't smell them, since they would approach by weaving back and forth, as sharks do - they can't see through the murky waters. We think, therefore, that they hear the "bait ball". We intend to test this theory. See project details: here: Gotham Whale Team and details
A "bait ball" is a tight school of menhaden, locally called "bunker" that forms when under predation by bigger fish like stripers, or bluefish. This is a defense mechanism since it distracts the predator by appearing as one body, not individuals that can be easily plucked off. Each menhaden, says, "eat him, not me, ... not me." It is a tactic employed by prey species from anchovies, to zebras.
But how does a "bait ball" make a sound that could direct a whale? Fishermen know them to make clicks on the surface by breaking the water with flicks of their tails. Is this a sound whales could hear? We would like to test that.
However, a more intreging clue appears. It is known that a closely related species, herring are know to make bubbles when under attack by predators. They have been shown to make a bubble cloud that may distract predators in the same manner as octopus do when they emit a cloud of ink. And bubbles make noise underwater!
Now don't descend into sophomoric humor, for this is an important scientific study, but how do the herring make the bubbles? It seems that they take air in through their mouths and expell it out their anus. As any schoolboy knows, this certainly makes a sound.
We think menhaden may use a similar strategy and have brought together a team of scientists to test the hypothesis. We hope you will help us in this effort.
This summer we will bring Dr. Edmund Gerstein, acoustic scientist, from Florida Atlantic University, to NY to deploy his recording equipment in schools of menhaden. While we are ultimately interested in this mechanism in the behavior of feeding humpbacks, we can perform the experiment on the fish without the necessity of aquiring a permit to study the behavior on feeding whales (if we are successful in determining that the menhaden indeed make an audible acoustic clue, we will extend the experiment to the whales).
Our budget needs are minimal, the costs being for Dr. Gerstein's transportation and lodging, boat time and local transportation. We are allotting a 10-day window for the experiment later this summer.
Help fund research for
and Humpback Whales
How do humpback whales find their next meal when feeding on menhaden "bait balls"? Gotham Whale intends to find out. Please help our experiment!