Researchers at Sea Life Park Hawaii are working on a way to get humans even closer to our flipper friends: They're devising a common language of dolphin-like whistles.
Already, dolphins recognize sounds for four words: ball, disk, leaf and barrel – all of which are objects that the dolphins being tested are familiar with.
"We have developed a whistle word language – words represented as whistles," said Dr. Ken Marten, director of the dolphin research initiative Project Delphis.
Marten's whistle language does not replicate the dolphin's language; rather, it is an artificial approximation of it.
"We wouldn't want to use whistles that will have a negative effect. We don't want to inadvertently tell them to get lost," Marten said.
The dolphins recognize the whistles as a form of communication, but it is a new kind of language to them. "They understand it as a language, but it's like gibberish to them," Marten said.
The creation of a cross-species auditory language has never been done before. A fairly sophisticated sign language has been developed with the great apes, but this is the first example of a "spoken" language.
The reason it has taken biologists so much longer to establish communication with dolphins than with apes is that dolphins are logistically so much harder to work with.
"They are not in an environment that we are used to, and this is a big obstacle," said Kim Bassos-Hull, senior biologist at Mote Marine Laboratory.
"Apes are physically more similar to us. They use their hands – body language like us. Dolphins are almost purely acoustic. We have to switch our thinking to totally acoustic," Bassos-Hull said.
And research at Project Delphis is not as sophisticated as ape sign language.
"The idea that there is an English-dolphin dictionary is not very feasible," said Barbara Brunnick, senior scientist at Wild Dolphin Project.
"My hesitation is that dolphins are primarily acoustic animals while humans are primarily visual animals. In humans, the most-used sense is vision; we use it to process data."
"For dolphins, the primary route to assimilate information is via sound. We have different approaches to the same information," Brunnick said.
Brunnick is confident, however, that communication with dolphins on a basic level – beyond simple word recognition – can be established.
"Using symbols along with acoustics should provide a way to bridge the gap in communication," Brunnick said. "We believe that communication this way is a viable possibility."
Bassos-Hull agrees. "It won't be free-floating conversation," Bassos-Hull said. "We'll be able to ask questions and they will be able to answer in very simple terms."
Despite the fact that Marten admits the research is "a huge undertaking," he is confident that he will have established communication within 10 years.
Marten, who has been working with three dolphins at the park, says the dolphins already recognize and repeat the artificial whistles he has devised.
However, they have yet to relate the whistles to the objects they refer to – this will be the next goal of the research. "The second stage is to see if the dolphins recognize what the whistles stand for," Marten said.
Marten records the dolphin's whistles via hydrophones connected to a computer. If the computer detects one of the four whistle words, it triggers an underwater touchscreen to display the image of the object, and then the whistle is repeated back to the dolphin.
The underwater touchscreen is the first of its kind. It's made up of an infrared beam grid mounted onto the tank window and a monitor screen that faces the dolphins.
The infrared beams are situated parallel to the tank's window by four mirrors tilted at 45 degrees.
When a dolphin's snout enters the infrared beams, the interruption in light is detected by the infrared beam grid and relayed to a computer.
"The touchscreen offers a methodology for understanding the dolphin's cognitive skills. It responds to both touch and whistles simultaneously," Marten said.
Marten has used the screen in a number of different experiments. "One experiment used the touchscreen like a jukebox; each quadrant of the screen was a different type of music," Marten said.
"The touchscreen is a kind of entertainment center for the dolphins," Marten said. "We instruct the dolphin so it knows that if they touch the screen something happens."
It's not all fun and games, though. Marten expects the dolphins to get down to some serious studying, too. "The touchscreen operates like a tutorial for human-dolphin communication," Marten said.
Marten's research team does not offer food rewards to the dolphins. "The rewards have to be of an intellectual nature," he said.
"The reward system is like a kid in an arcade – they have to want to see what happens if they trigger something off," Marten said. "In this sense, the dolphins direct the research."
"We don't use food rewards because (we want) our results (to) be bullet-proof. Critics will not be able to say that you can train a dolphin to do anything by offering it food rewards. We want to show that the dolphin learned of its own volition," Marten said.
The ultimate goal of Marten's research is to illustrate to the world the high intelligence of dolphins and the need to protect the species.
"Dolphins are being killed by the millions so we can get our tuna. It's like what people used to say about the American buffalo – 'Gee there used to be buffalo up on those hills.' The same will be true of the dolphins if we do not act," Marten said.