Human-dolphin fishing cooperatives

1. They have been reported to exist in Australia, India, Mauritania, Burma, and the Mediterranean, but the best known are in Brazil.

2. In parts of southern Brazil, human fisherman have been cooperating with dolphins for many generations (of each species).

3. If fishermen clap just the right way, dolphins will herd fish into the desired areas of fishermen, in muddy lagoon areas.

4. The dolphins perform a distinctive kind of dive to signal to the humans it is time to cast the net for the fish.

5. Only some individual dolphins are able (willing?) to do this well, perhaps the others belong to the forty-seven percent.

5b. The dolphins which cooperate with the fisherman are also more social, more socially connected, and more cooperative with other dolphins.

6. The Brazilian fishermen name the star cooperating dolphins after ex-presidents, soccer players, and Hollywood stars.

7. The names aside, it is not clear whether dolphins benefit from offering this assistance; some commentators suggest the dolphins end up with isolated or injured fish from these exercises.

Here is one blog post report on these practices.  Here is one piece of the original research.  I stumbled upon this while reading the new and excellent Hal Whitehead and Luke Rendell The Cultural Lives of Whales and Dolphins, a new book from University of Chicago Press.

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From Wikipedia:

The killer whales of Eden, Australia were a group of killer whales (Orcinus orca) known for their co-operation with human hunters of other whale species. They were seen near the port of Eden in southeastern Australia between 1840 and 1930. A pod of killer whales, which included amongst its members a distinctive male called Old Tom, would assist whalers in hunting baleen whales.[1] The killer whales would find target whales, shepherd them into Twofold Bay, and then alert the whalers to their presence and often help to kill the whales.
Old Tom's role was commonly to alert the human whalers to the presence of a baleen whale in the bay by breaching or tailslapping at the mouth of the Kiah River, which is one of the smallest rivers, where the Davidson family had their tiny cottages. This role endeared him to the whalers and led to the idea that he was “leader of the pack,” although such a role was more likely taken by a female (as is typical among killer whales),[1] probably the whale known as Stranger. After the harpooning, some of the killer whales would even grab the ropes in their teeth and aid the whalers in hauling. The skeleton of Old Tom is on display at the Eden Killer Whale Museum, and significant wear marks still exist on his teeth from repeatedly grabbing fast-moving ropes.[1] In return for their help, the whalers allowed the killer whales to eat the tongue and lips of the whale before hauling it ashore, providing a rare example of mutualism between humans and killer whales.[1] The killer whales would then also feed on the many fish and birds that would show up to pick at the smaller scraps and runoff from the fishing.

http://en.wikipedia.org/wiki/Killer_whales_of_Eden,_Australia

"Killer Whales of Eden" would be a good name for a rock band.

I'm authentically surprised. The are hunting dogs, hunting falcons, but.......fishing dolphins? Dolphins as domestic animals by year 3000?

Aren't they domestic now?

I mean, captive dolphins are more cooperative than cats. By a huge margin.

Almost any creature is more cooperative than cats.

Just try not to test this around a wild lion, or a hammer shark.

But looks like soon enough we'll get in a situation where every species still alive must be considered domestic.

Admittedly, not a very high bar.

For an animal to be considered domestic, humans must control their breeding. Something that is technically possible now, but most captive dolphins are caught from the wild. While trained elephants have been used in India for perhaps thousands of years, they are not domesticated because humans don't control their breeding. The closest humans have come to controlling elephant breeding is to jump out of the way in time.

"it is not clear whether dolphins benefit from offering this assistance"

Then, why would they do it? It is not as if they are enslaved -- conditioned, sure -- but not enslaved.

Animals do lots of things that are bad for them. My dog used to try to eat chocolate all the time. My cat used to enjoy escaping our house and walking in the middle of the street, until it got hit by a car.

"So long, and thanks for all the fish!"

You beat me to it!

Also, I'd imagine the fishermen throw back any fish they don't want. That means an easy meal for a dolphin.

Some dolphins are lifters and some are leaners,

There's also this: http://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=3613343

There's a British documentary/recreation of the event kicking around too.

Spoke to a friend of mine from Brazil about this. He said that when the fish are driven into the net, their school breaks apart, and it becomes every fish for himself.

The dolphins thus benefit because the individual fish that escape the net are easier for the dolphins to catch than when they're in a group.

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