The Whale Sharks are Coming!
So, do you know whale sharks? They’re massive sharks right out of a horror movie like Jaws… except they eat plankton. I think they’re amazing. You’d think the only reason that they’re called whale sharks is their massive size, but considering what they eat, it’s obvious they also have other things in common with whales (baleen whales, anyway).
de la Parra Venegas R, Hueter R, González Cano J, Tyminski J, Gregorio Remolina J, et al. (2011) An Unprecedented Aggregation of Whale Sharks, Rhincodon typus, in Mexican Coastal Waters of the Caribbean Sea. PLoS ONE 6(4): e18994. doi:10.1371/journal.pone.0018994
Although whale sharks are generally solitary animals, you can sometimes find groups of them in areas with high concentration of zooplankton. These groups usually consist of dozens of whale sharks. However, it turns out there are some places where loads of them will gather, and the Gulf of Mexico (more precisely the waters around the Yucatán Peninsula) is one of those places. Turns out that the sharks seem to be attracted by the mass spawning of fish. In the article, little tunny gets a mention as an unexpected and prolific species. Apparently, little tunny usually spawn in the Mediterranean. That’s quite far from home, then. When the fish spawn on the out side of the Yucatán Peninsula, several hundred whale sharks will gather to feed on the fish eggs. Imagine that. You and all your little fishy friends gather together to create the mother lode of a next generation, and several hundred whale sharks drop by and eat all your babies. Must be annoying.
The authors point out that it’s not only whale sharks but all sorts of other large inhabitants of the sea such as sea turtles and a variety of rays gather in the nutrient rich waters of the Gulf of Mexico and that knowing this, we should make an effort to protect the area (did someone mention oil spills?).
Funny thing. Local fishermen had known about the gatherings of whale sharks for a long time, perhaps even generations. They just hadn’t bothered to tell researchers about them until recently. We researchers should really put more of an effort into getting as much knowledge as possible out of local experts.
- Video: World’s Biggest Gathering of Whale Sharks (wired.com)
- Big sharks. Big mystery. (conservationbytes.com)
- Zoologger: Flashmob gathering of world’s largest fish (newscientist.com)