Last week the Centre for Whale Research, in Washington State USA, confirmed that a calf had been born to the L pod family of Southern Resident killer whales.
This is the first calf born into the L pod family since January 2019. The mother is L86 (nicknamed Surprise) and the sex of the baby (L125) is not yet known, but looks to be in good condition. After hearing reports of the J, K and L Southern Resident pods in Haro Strait near San Juan Island, the Centre for Whale research dispatched field researchers who encountered and photographed the new calf, which seemed to be just a few weeks old, with foetal folds still showing on the skin.
The Southern Resident killer whales are a large extended family (or clan) which consists of three pods; J, K and L and are the smallest of four resident killer whale communities within the North America Pacific Ocean. This population is listed as endangered, so every calf is vitally important – they are in fact the only killer whale population listed under the Endangered Species Act by the National Marine Fisheries Service, National Oceanic and Atmospheric Administration (NOAA). From spring to fall the three pods are most often seen travelling in areas which make up the Salish Sea (The Puget Sound, Strait of Juan de Fuca and the Southern Georgia Strait) but are also recorded in coastal waters as far south as Monterey Bay in the winter and early spring and off the coast of California, Oregon, Washington and Vancouver Island, British Columbia. Members of L pod have even been seen in Southeast Alaska. The range of the Southern Resident killer whales appears to follow returns of the Chinook salmon to major rivers in the Pacific Northwest and California. The Southern Residents are fish eating killer whales and Chinook salmon appears to be their preferred food over other species of fish.
Each Southern Resident clan (J, K and L) uses a distinctive dialect of calls to communicate with each other, some of which are shared between all three pods. These calls and clicks are unlike the calls used by any other killer whales and can travel 10 miles or more underwater. Within each pod of the Southern Residents, families form into sub-pods which are centred around older females, usually grandmothers or great grandmothers. Both male and female offspring remain in close contact with their mothers for life.
The L pod is the largest of the three Southern Resident pods, consisting of 33 individual animals. The eldest female (L25) is believed to have been born in 1928 and is not only the oldest in the L pod but also in the whole Southern Resident population. In December 2020 the Southern Resident population totalled 74 individual animals (J pod = 24, K pod = 17, L pod = 33) so this birth of the new calf brings the total to 75 animals in the wild. It is believed that in 1970, during whale captures for marine park exhibitions, a female member of the L pod was taken into captivity and is still living at the Miami Seaquariam. In 2020 two calves were born to the J pod and both still look to be doing well.
According to research from the Centre for Conservation Biology, the Southern Resident killer whales lose around two thirds of their pregnancies, linked to nutritional stress. The mother of the new calf (L86) was born in 1991 and has previously lost two of her babies; in 2012 her calf L112 was killed by blunt-force trauma and in 2014 another of her calves died. Her first calf, born in 2005, is still swimming near his mother today.
As with all cetaceans, the Southern Residents face a number of threats to their survival. These include; noise pollution from tour boats and larger vessels, chemical pollution from polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs), and a decline in prey, especially the Chinook salmon. The new L pod calf is welcome news and is vital to their population. “It’s just wonderful to see a new birth this early in the year; it’s pretty exciting,” said Deborah Giles, researcher with the University of Washington’s Centre for Conservation Biology. “It gives you hope for the other ones.”