Baby boom continues for Southern Resident orcas

A new calf born in K pod is seen swimming with its mom, K-12, also known as Sequim.
Photo by Emma Foster, courtesy of Center for Whale Research

Everyone I know who studies and loves killer whales is pleased to see a continuing series of births among all three pods that frequent the Salish Sea. It’s a good sign to have such a variety, and the calves seem to be surviving at a high rate.

The population is gradually rebuilding itself, with the latest news being a new calf in K pod. Here’s the story I wrote for today’s Kitsap Sun, which was posted on the website:

FRIDAY HARBOR — A new orca calf has been born in K pod, one of the three groups of killer whales that frequent the Salish Sea and Puget Sound, experts say.

The young calf, designated K-43, was spotted Tuesday swimming with K-12, presumed to be the mother, according to biologists with the Center for Whale Research. It is the third calf born to the three Southern Resident pods this year.

K pod returned to the San Juan Islands this week by way of the Strait of Juan de Fuca, but apparently turned back. All three groups are beginning to settle in for a summer of fishing in and around the islands. J pod and portions of L pod have already arrived, but both pods have been coming and going, apparently not finding many chinook salmon, experts say.

The new whale apparently was spotted by observer Jeanne Hyde on Feb. 21 while K pod traveled with J pod in the San Juan Islands. At that time, the calf could not be positively confirmed, but it now looks to be five months old.

K-12, the new mother, is believed to be 38 years old.

She was a young animal when Ken Balcomb, the center’s director, began to identify individual whales and maintain an annual census. She has two other offspring, K-22 and K-37.

The new birth brings the number of whales in K pod to 20. J pod has 28 whales, and L pod 42. Final counts for this year won’t be made until all the whales have returned.

For the past few years, the Center for Whale Research has been reporting births and deaths as they are observed. It is much easier to take note of births, because the young whales are quite obvious. Deaths are tougher, because it takes time to decide whether a whale is gone for good or just off somewhere else. A good count of the whales traditionally comes in summer, when all three pods are around long enough for Ken Balcomb and his crew to make a complete tally.

As of now, the total count of the three pods stands at 90, according to a running tally kept by Orca Network, based on reports from the Center for Whale Research. That number was last reached in 2004. (See chart by Orca Network.) A recent high of 96 animals was reached in 1996, the year before 19 members of L pod spent a month in Dyes Inlet. If I recall, the number of killer whales was estimated to be close to 200 before the decline brought about by capture for aquariums during the 1960s and early ’70s.

4 thoughts on “Baby boom continues for Southern Resident orcas

  1. Great news! With fewer than 30 reproductive members, the Southern Resident population needs all the calves they can get. NOAA figures that the population needs to grow by 2.3 percent per year — for 28 years — before it gets removed from the endangered species list. That would make it somewhere around 160 whales. And since about half of all calves don’t survive their first year, they’ll need a lot of births.

    One more reason why it’s crucial to get them enough salmon: fecundity drops by 50 percent in the year after a low-salmon-return year.

  2. I’ve just looked into that figure of 50% neonate mortality rate for orca babies. It is generally used, but it’s based on some very squishy numbers published in 1990 in a paper by Olesiuk, Bigg and Ellis.
    Here is a 2005 study by Olesiuk, Ford and Ellis on the Northern Resident orca community, with a note about the 1990 study:
    Life History and Population Dynamics of Northern Resident Killer Whales (Orcinus orca) in British Columbia

    We made no attempt to estimate mortality within the first 6 months of life. Since most births occurred outside our field season, calves were generally first encountered when they were about 6 months of age. Although this makes it impossible to estimate neonate mortality from the summer survey data, we suspect mortality at birth and in the first few months of life is high. Olesiuk et al. (1990) inferred it could be as high as 37-50%, although in retrospect that is probably on the high side.

    I hope to watch little baby K43 become big grownup K43 and frolic in these waters for many decades.

  3. The correlation between Chinook run sizes and orca mortality and fecundity is direct and impressive. It seems to defy logic and wildlife biology for the Southern Resident orcas to restrict their diet to 80% Chinook, but it made sense until around 100 years ago. These are fascinating animals with a strong sense of tradition and loyalty. Maybe we can’t have it all plus growth forever, so I hope we can make abundant salmon one of our highest priorities.

  4. Thanks for these observations, Howie.

    What I’ve always understood is that the first-born calf is at the most risk because the mother “off-loads” a significant amount of her toxic load to this young animal and less to her subsequent offspring.

    The death of a fetus or neonate may go undetected, and researchers may not know whether a subsequent birth is the first or the second calf for a female killer whale.

    In recent years, new calves are being identified soon after birth with more frequency, so it should be possible to calculate a rough survival rate that includes calves younger than the six-month limit mentioned in the 2005 study. But determining how how many die at or before birth is a much bigger challenge.

    What I find hopeful is speculation that a new generation of Southern Resident killer whales may have lower toxic loads than their parents and grandparents. This could put the whales on a path to recovery, provided they can find enough food. But rebuilding the food chain is a major challenge, isn’t it?

Leave a Reply

Your email address will not be published. Required fields are marked *

Before you post, please complete the prompt below.

Please enter the word MILK here: