Swimming With Whales
A group of whales in the Atlantic Ocean adopts an orphaned dolphin
PHOTO: The dolphin has a curved spine, which may cause it to swim more slowly. (Barcroft Media / Landov)
MAP: Scientists found the pod off the coast of the Azores—islands that are part of Portugal. (Jim McMahon)
A male bottlenose dolphin was recently spotted swimming with a pod of sperm whales off the coast of the Azores, a series of islands in the Atlantic Ocean between North America and Europe.
This friendly scene has captured the attention of scientists. Why? Because although dolphins have been known to become friendly with other species, it is extremely rare for whales to do so.
“It really looked like they had accepted the dolphin,” says Alexander Wilson, one of the scientists who saw the two species play together. Wilson studies animal behavior at the Leibniz Institute of Freshwater Ecology and Inland Fisheries in Berlin, Germany.
FRIENDS TO THE RESCUE
Wilson and fellow scientist Jens Krause were in the Azores to study the behavior of sperm whales. They were surprised to find a dolphin nuzzling with a group of sperm whales over the course of eight days.
The scientists were able to tell it was the same dolphin each time because of an S-shaped curve in its spine. They think that this deformity caused the dolphin to swim more slowly—and possibly to be left to survive on his own. Dolphins normally swim very fast; Wilson guesses that the dolphin lost his own pod and fell in with the sperm whales instead.
Why the sperm whales adopted the dolphin is a mystery. “It could be a form of social ‘play,’ or it could be that the sperm whales interpreted the dolphin as being another sperm whale calf,” Wilson and Krause wrote in a scientific paper about the odd pod.
The dolphin was lucky that the sperm whales accepted him—a dolphin living alone would probably get lonely and would certainly be in danger. Dolphins are social animals and normally swim in large family groups called pods. The size of each pod varies but is usually no larger than a dozen dolphins. Dolphins in a pod help one another avoid predators and share food. They also help out if one of them is injured.
WHALES IN DANGER
The sperm whales that scientists were studying in the Azores are endangered. That means there is a possibility that these species could become extinct, or completely die out. Scientists hope that what they learn about sperm whales can help humans to better protect them.
One of the biggest threats to sperm whales is whale hunting, called whaling. Whales were overhunted for many years. The International Whaling Commission banned hunting whales in 1986, and most countries have agreed to stop fishermen from whaling since then.
Bottlenose dolphins aren’t on the endangered species list, but there are several areas of the world where other types of dolphins are in danger of extinction. Fishing, pollution, and environmental changes are among the factors that threaten them.