Underwatertimes.com News Service - November 20, 2006 19:09 EST

A new study has revealed that humpback whales are capable of emanating as many as 622 social sounds.

Scientists believe the whales' broad vocal repertoire enables them to communicate with their fellow whales, like summoning their young or even wooing potential mates by expressing emotions.

Rebecca Dunlop, a researcher in the School of Veterinary Sciences at the University of Queensland, Australia said that while some sounds are brief, some are unpatterned, distinct from lengthier, complex whale songs.

She said the study threw new light on the fact that whales convey more meaning through vocalizations than previously thought.

"I wouldn't say (whales possess) language, as that's a human term. Whales don't string these sounds together like words and form sentences. It's more like a simple vocabulary," Discovery News quoted Rebecca as saying.

For their study, the team used a static hydrophone array - sensitive equipment that detects sound waves - to visually track 60 pods of whales migrating along the east coast of Australia.

The waves linked the whale sounds to various activities and contexts.

The team identified 622 distinct sounds, which fell into 35 basic types.

Rebecca said these included "wops" made by females, "thwops" made by males, "yaps" made when pods split, and high pitched cries that appeared to express anger.

In addition to vocalizations, the team also found that whales sent messages through body language - by breaching the surface, slapping water with their tails and blowing underwater bubbles.

She said the whales also sometimes even "speak" short song units individually instead of singing them. Males especially seem to do this when trying to woo a female.

"Song is a loud broadcast signal and two singers singing at the same time is bound to be confusing to the receiver. If he's trying to attract a female, but doesn't want his signal confused with another singer in the area, then using song units in this case might be the way forward," Rebecca said.

The study will be presented at the upcoming joint meetings of the Acoustical Society of America (ASA) and the Acoustical Society of Japan in Hawaii.