Tuesday, February 17, 2009

Update on the Southern Resident Whales as of February 17, 2009

Two new orca calves, but one adult whale is missing
Journal of the San Juans Editor
Today, 2:29 PM · UPDATED

Researchers have confirmed the birth of two Southern resident orca calves, bringing the population to 85.

However, the news comes as one 31-year-old male orca is believed missing, emphasizing the challenges the endangered whale pods face in their recovery.

The latest newborns were spotted swimming with J and L pods off Victoria on Feb. 6 and off Nanaimo Feb. 8. The parentage is not yet known.

"We like to have several encounters before know if (the calf) was hanging out with an auntie or grandma for a while," said Ken Balcomb, executive director of the Center for Whale Research.

Both whales were photographed by Balcomb off Victoria, B.C., Feb. 6. L112 was photographed off Depoe Bay, Ore., by Morris Grover on Jan. 21 and by Carrie Newell on Jan. 24. J44 was photographed again on Feb. 8 near Nanaimo, B.C. by Dr. John Ford.

"We are analyzing all of the photographs taken in these encounters, and will analyze photographs taken later this spring to confirm the mothers' identifications and the calves' survival," Balcomb said.

Balcomb said it's unusual for the three whale pods to be in inland waters in winter. Balcomb believes their presence here is linked to the depressed runs of Central Valley stock chinook in California, the whales' usual winter hunting area.

"Our typical first sighting is about May," Balcomb said.

The center's records have the current Southern resident orca population at 25 in J pod, 19 in K, and 41 in L — if L57 shows up.

The historical average age for male Southern resident killer whales is 29, with a maximum in the 50s, Balcomb said. The historical average for females is 52; the oldest female, J-2, is in her 90s and may be 100.

The whales' population has seesawed over the past several years. Six orcas disappeared in 2008, dropping the population to 83, the lowest since 2003.

The Center for Whale Research and others are blaming marine pollution, depleted salmon runs, and acoustic impacts from dredging, seismic testing and military sonar for the decline in the population. The Southern resident orcas are listed as endangered in Canada and the U.S.

The orca pods are called "residents" because they spend a majority of the year here, chasing the salmon runs.

One of the whales believed to have died last year, L67, showed signs of malnourishment the last time she was seen; she had "peanut head," a term for a depressed area behind the blowhole that normally stores fat. L67's offspring also have not fared well either: L98, also known as Luna, separated from the pod in Nootka Sound in 2002 and was killed by a boat propeller in 2006. L101, a juvenile male, failed to return with the pod last year.

The resident orcas have long been beleaguered. In the late 1800s and early 1900s, fishermen saw them as competition and shot them. Later, orcas were captured for marine parks.

Their population, believed to have once been in the 120s, plummeted to 71 by 1973. It rebounded to 99 in 1995, then plummeted to 79 six years later.

The population rebounded to 80 in 2002, 83 in 2003, 85 in 2004 and 89 in 2005, then seesawed around 88 since then. The local pods were declared endangered by the U.S. and Canada by 2005 and the National Oceanographic and Atmospheric Administration has been patrolling the area to enforce rules requiring boats to maintain a distance of 100 yards from the whales.

In an earlier interview, Balcomb said the ups and downs of the orca population over the last 30 years parallel the ups and downs of the chinook salmon population. "If the chinook population doesn't do well, the whale population doesn't do well," he said.

Balcomb suggested that a 10-year moratorium on salmon fishing would enable salmon populations to rebound. But even a suggestion of a moratorium by fisheries managers would be politically difficult, he said.

The whales have been designated J44 and L112.

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