About This Species
Beluga whales—the distinctive white whales that live in the Arctic and sub-Arctic region—are social animals that can be found in pods, cutting through icy waters. The whales are extremely vocal, and they whistle (and squeal, and chirp) as they go. Some of the sounds allow them to communicate; others allow them to echo-locate objects around them. The Beluga's scientific name, Delphinapterus leucas, means "white dolphin without wings," which alludes to the fact that unlike most other whales and dolphins, Beluga whales do not have a dorsal fin.
Female Belugas can measure up to 13 feet, while males can grow up to 16 feet. The whales can live up to 60 years, they have teeth and they prey on a wide array of fish. Belugas are able to live comfortably in icy waters, which is lucky for them since one of their primary predators—killer whales—cannot. Like most species in the Arctic, the whales' lives are linked to the sea ice. In addition to providing them refuge from killer whales, the timing of the spring melt and the fall freeze is integral to the Belugas' migration.
Their other predators are polar bears, which hunt for the whales along cracks in the sea ice, and humans. In the Arctic, Belugas are hunted by indigenous people. The main incentive is the whale's skin, which is considered a delicacy.
Some Belugas have permanent homes, while others migrate. Those that migrate typically return to the same locations each year. In the warm months, Belugas can be found in fjords, bays and estuaries where they are able to find food and where the water temperature is ideal for raising calves. Those areas freeze over as the weather turns, though, pushing the whales into offshore waters.
In recent years, Beluga whales have been showing up in unexpected areas. According to a study published this week in the journal Royal Society Biology Letters, the whales are straying from their normal migration routes during years when the sea ice forms or melts differently than it has historically.
The Arctic is warming at twice the rate of the rest of the globe and the most visible impact is to sea ice. Since 1979, it has declined an average of 13.3 percent each decade. Summer sea ice hit record lows in 2007 and again in 2012, and levels have remained far below the historical (1979-2000) average.
The shifts in the Beluga whale's migration patterns, the report's authors write, were likely caused by the changes in sea ice.
The Belugas of Cook Inlet, Alaska, do not migrate and are the most isolated subpopulation of the whales. Between the late 1970s and 2014, the Cook Inlet population dropped from as many as 1,300 to an estimated 314 whales, in part due to subsistence hunting by Native Alaskans through the late 1990s. Their precipitous decline led to the whales being designated as depleted under the Marine Mammal Protection Act and the number of Belugas allowed to be hunted was strictly limited. Between 1999 and 2015, just five Beluga whales were killed in subsistence hunting. In 2008, the Cook Inlet Belugas were listed as endangered under the Endangered Species Act.
The Beluga Whale's Range
In the summer, Belugas travel across the northern reaches of the Arctic. As the weather cools and the ice sets in, they head to the southern parts of their range.
Beluga whales face a number of threats as the climate continues to change. As weather patterns shift and the ice becomes increasingly unstable, the whales risk being trapped in the ice. This has always been a factor in Beluga mortality, but is expected to rise.
Likewise, as more of the Arctic ocean becomes ice-free for longer periods, Belugas risk increased exposure to some of their predators. Low ice years are already bringing more sightings of killer whales in the far North, and there have been observations of killer whale attacks on Belugas. This is expected to increase.
At the same time, more humans will be accessing the Arctic, bringing with them toxic contaminants. When toxins are introduced to an ecosystem, they become concentrated the higher they move up the food chain. For species like Belugas, who are at the top of the food chain, that poses an acute risk.