Oldest male in Southern Resident orca KPod presumed dead

An orca is presumed dead after being found in distress last week in the Strait of Juan de Fuca, a body of water that separates Washington state from Canada, officials said.

The cause of death for the Southern Resident orca pod’s oldest male, known as Cappuccino or K21, is still undetermined, but could include starvation, a chronic disease such as cancer, or both, according to Paul Cottrell of Canada’s Department of Fisheries and Oceans Marine Mammal Unit.

The Orca Behavior Institute reported that the whale was seen swimming far behind the rest of the pod with no signs of physical injuries, ruling out the likelihood of a ship strike. At 35 years old, it is more likely that he died of illness. The average lifespan of male killer whales is 30, SeattlePI.com reported.

Born in 1986, K21 was one of the most identifiable residents with check-mark-shaped saddle patches and a notch in his tall dorsal fin. He had been living without any immediate family members after his sister’s 2012 death and was "adopted" by K16, a female whale known as Opus, who was born the year before him.

Shields suggested K21 might have chosen to be alone in his final moments, explaining why he fell behind the rest of the pod.

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"In recent years, all three Southern Resident pods have gathered several times in the Salish Sea alongside a birth or death in the population," Institute Director Monika Wieland Shields wrote in a Facebook post.

With K21 presumed dead, the number of southern resident orca whales drops to 74.

One whale calf has been born this year, a female orca known as L12 in February. Last year, the J pod welcomed two new calves. The K pod — the smallest of the three resident pods — has not had any viable offspring since 2011.

The whales have in recent years been at their lowest numbers since the 1970s.

Last week, the endangered killer whales received new habitat protections from the U.S. government. The National Marine Fisheries Service on Friday finalized rules to expand the southern resident orca’s critical habitat from the Canadian border down to Point Sur, California, adding 15,910 square miles of foraging areas, river mouths and migratory pathways.

While environmentalists praised the action, many also called for habitat protections for salmon to aid in the orca’s recovery.