Conversing with dolphins

Up to now,dolphins have shown themselves to be adept at responding to human prompts,with food as a reward for performing a task. “It’s rare that we ask dolphins to seek something from us,” Herzing said. But if she is right,the dolphins will seek to communicate with humans,and the reward will be social interaction itself,with dolphins and humans perhaps developing a crude vocabulary for objects and actions. How far will dolphins go to engage? “The key is going to be coming up with a system in which the dolphins want to communicate,” said Stan Kuczaj,director of the Marine Mammal Behavior and Cognition Laboratory at the University of Southern Mississippi. Kuczaj developed an early two-way communication system while working at a captive lab in Orlando in the late 1980s. The system relied on visual symbols,not sound,and used a large stationary keyboard that proved to be too cumbersome. But he says the effort gave him confidence that such a system could work and Herzing is “definitely the closest to getting there.”

Herzing’s work has been compared to that of Jane Goodall,whose studies of chimpanzees also entailed decades of observational fieldwork. In 1985,as a researcher with the Oceanic Society,she found this spot in the Bahamas,where the conditions seemed perfect for dolphin observation. That year she started the Wild Dolphin Project,and began using video to document dolphin society. The project is largely financed by foundations,including the Annenberg Foundation. In 2008,Herzing was awarded a Guggenheim fellowship. Back on her research vessel,a 62-foot catamaran called the Stenella (the Atlantic spotted dolphin is Stenella frontalis),Herzing reviews video from the day and logs moments of foraging,courtship and play into a growing database. With a few keystrokes she can summon 25 years of video on a specific behaviour—say,a mother foraging with a calf,which can lend insight to how dolphins teach their children to find food. Dolphins are known to make three types of sounds: whistles,clicks and burst pulses. Whistles are thought to be identification sounds,while clicks are used to navigate and to find prey with echolocation. Burst pulses,which can sound like quarreling cartoon chipmunks,are a muddy mixture of the two,and Herzing believes much information may be encoded in these sounds,as well as in dolphins’ ultra-high frequencies,which humans cannot hear.

The two-way system she will test next year is being developed with artificial intelligence scientists at Georgia Tech. It consists of a wearable underwater computer that can make dolphin sounds,but also record and differentiate them in real time. It must also distinguish which dolphin is making the sound,a common challenge since dolphins rarely open their mouths. In the new system,two human divers interact in front of dolphins: First they play a synthesised whistle sound,then one hands the other a scarf or a piece of seaweed. The idea is to establish an association between sound and object. Dolphins are excellent mimics,and the hope is they will imitate the whistle to request an object or initiate play.ERIK OLSEN