Ever wondered what dolphin and whale squeals mean? Scientists now suggest that those squeaky sounds mean they're delighted or happy about something.

The squeal is different from the usual buzz dolphins and whales make to call on their prey. This sound is only heard once they are rewarded with food as expression of their delight.

This observation was recently published in the Journal of Experimental Biology last August 13. The marine mammal program team at the University of Hawaii in Kane'ohe Bay specifically studied bottlenose dolphins and beluga whales.

Paul Nachtigall may not be part of the study but he has noticed the sounds during his previous studies.

"I had one of my dolphins during my dissertation emit a little squeak each time he pressed a paddle, even though he only received food on the average of once per minute," Nachtigall shared.

Nachtigall also said the new study could be an alternative explanation of the sounds that are emitted while approaching the fish as reward and even after eating.

The sound is called the "victory squeal" and it isn't emitted while a dolphin or whale is still trying to locate fish. The sound is likened to giggling children according to the new study.

Buzzing sounds from these marine mammals are normal. They use sounds everyday to communicate and navigate. While the squeals are emitted when food is available, the animals also squeal even after the reward is given.

The president of the National Marine Mammal Foundation, Sam Ridgway, has spent a lot of time studying bottlenose dolphins and beluga whales. His work includes training the marine mammals by giving them rewards.

"We noticed that each time an animal took a fish, it would make this particular pulsed sound," said Ridgway.

Ridgway first noticed these cries of delight. His wife suggested it could be like giggles of children when being presented with something fun or are happy. Ridgway and his colleagues did further observations by training the belugas and bottlenose dolphins. The researchers had the animals perform tasks and were given treats as reward. But before a treat is given, they would whistle a buzzer to the whales and dolphins a reward is coming.