Sperm whales are one of the deepest diving whales on the planet and make dives of more than 2000ft below the ocean's surface lasting up to an hour while they search for the squid they feed on.
The calves, however, cannot make these dives and have to remain at the surface. This leaves the calves vulnerable to killer whales which often follow pods of sperm whales to prey upon.
Four of the six baleen whale species found in the western North Atlantic Ocean (humpback, sei, fin and blue) have changed their distribution patterns in the past decade.
Using 281 passive acoustic recorders moored to the sea floor from the Caribbean Sea to Greenland, researchers from the United States and Canada monitored the movements of the whales from 2004 to 2014. The findings of their study was published in the Global Change Biology journal.
Belugas are gregarious, highly sociable and they regularly form small groups, or pods, which may contain between two and 25 individuals, with an average of 10 members.
Rice's whale (Balaenoptera ricei), previously believed to be a population of Bryde’s whales, is an intermediate-sized species of baleen whale.
“I was surprised that there could be an unrecognized species of whale out there, especially in our backyard,”
—Lynsey Wilcox, geneticist with the US National Oceanic and Atmospheric Administration
We asked our contributors what their favorite marine mammal dive was and they sent us tales and images of magnificent whales, playful seals, endearing sea cows and curious dolphins.
Currently, there are only 400 of these whales left in the wild.
The first calf was seen on December 4, near Cumberland Island, Georgia. Then, on December 7, the second calf was spotted swimming alongside bottlenose dolphins off Vilano Beach, Florida.
When whaling all but exterminated the Antarctic blue whale 50 years ago, the waters around South Georgia fell silent. Between 1998 and 2018, dedicated whale surveys off the sub-Antarctic island yielded a sole blue whale sighting. But a whale expedition this year and analysis by an international research team resulted in 58 blue whale sightings and numerous acoustic detections, raising hopes that the critically endangered mammal is finally recovering five decades after whaling was banned.
It’s been a quiet summer in the waters of Alaska.
With zero cruise ships carrying whale-watchers and glacier gazers—a situation which temporarily boosts the state’s population of 730,000 by 1.4m individuals—the humpback whales in the vicinity have grown much more talkative.
This is the impression that delighted researchers are getting.
Slipping softly into the water, I had a straight path to the mother and calf that were resting near the surface only a short distance away. We closed the gap as quietly as a group of excited first-time whale watchers could manage and were rewarded with an initial glimpse of humpback whales from under the water. The newborn stayed close to its mother and swam up and over her rostrum as we looked on.
Every summer, East Australian humpback whales migrate from the feeding grounds in Antarctica to their breeding grounds in the Great Barrier Reef. They remain there for about several months, before making their way around the southern Australian coast back to Antarctica for the winter.
This scenario may one day become reality. And to be efficient, such robots would need to be maneuverable and stealthy, and be able to closely mimic the movements of the marine creatures.
Scientists like Keith W. Moored are working on the next generation of underwater robots by studying the movements of dolphins and whales. "We're studying how these animals are designed and what's beneficial about that design in terms of their swimming performance, or the fluid mechanics of how they swim."
