A research project that involved tracking the travels of K pod
for more than three months in the Pacific Ocean apparently has
ended, as the transmitter seems to have run out of battery power,
according to research biologist Brad Hanson.

“This has been a phenomenal deployment,” Brad told me yesterday
after it appeared he had logged the final transmission from K-25.
“It has been a quantum leap forward for us in terms of
understanding what is going on.”
K-25 is a 22-year-old male orca who was implanted with a
satellite tag on Dec. 29. The battery was expected to last for
32,000 transmissions, and it actually reached about 35,000, said
Hanson of NOAA’s Northwest Fisheries Science Center. No data
arrived yesterday during the normal transmission period.
The three months of satellite tracking data will be combined
with fecal and prey samples from a 10-day research cruise to serve
up a wealth of information about where the Southern Resident killer
whales go and what they eat during the early part of the year, Brad
said. Until now, this has been a major blank spot in the
understanding of these whales, he noted.
The information gathered over the past three months should prove
valuable in management efforts to protect and restore these orcas,
which are familiar to human residents of the Puget Sound region.
After the data are analyzed, federal officials should be able to
say whether they have enough information to expand “critical
habitat” into coastal areas for the endangered killer whales. If
not, we should know what additional information may be
required.
Brad says he feels a high level of anticipation from his fellow
killer whale experts who are eager to learn of the research
findings, especially the results of what the whales are eating.
“We have a tremendous amount of data, and we’re trying to push
it through as quickly as we can,” he said.
Brad says he won’t release the findings until the analysis is
further along. But he did dangle this intriguing tidbit in front of
me: The whales are NOT eating chinook salmon exclusively.
The tracking project has another benefit, Hanson said. It will
bring new meaning to more than three years of acoustic data
(recorded sounds) picked up by hydrophones dispersed along the
Washington Coast. Until now, it was not possible to determine the
locations of the whales from their sounds alone, because the sounds
could be picked up from many miles away. Now, thanks to tracking
data, the intensities of their calls and echolocation clicks can be
correlated with distance to a greater extent. Researchers are
developing a computer model to identify possible locations from as
much as seven years of hydrophone data in some places.
The tracking project began on Dec. 29, when K-25, named Scoter,
was darted with a satellite tag near Southworth in Kitsap County.
K-25 and presumably the rest of K pod then moved out into the
ocean. Check out the tracks on NOAA’s
satellite tagging website.
“We were extremely lucky to get that tag at the end of the
season,” Hanson said.
It was K pod’s last trip into Puget Sound for several months, he
noted, and it is a real challenge to get close enough to dart a
killer whale, especially when only certain ones are candidates for
the tag.
By Jan. 13, the whales had reached Northern California, where
they continued south, then turned around at Point Reyes north of
San Francisco Bay. They continued to wander up and down the West
Coast, including Northern California, into early March. After that,
they began to stay mainly off the Washington Coast with trips into
northern Oregon. They seemed to focus much of their attention near
the Columbia River, where early runs of salmon may be mingling.
The research cruise, originally scheduled for three weeks, ran
from March 1 to March 10, cut short by the federal budget
sequestration. By following the whales, researchers were able to
collect 24 samples of prey (scales and/or tissues of fish) plus 21
fecal samples from the whales themselves. Shortly before the
cruise, K pod met up with L pod, probably off the Washington
Coast.
The ability to track the whales and the fortune of decent
weather were major factors in the success of the research cruise,
Brad said. In contrast, several previous cruises had netted only
two prey samples and no fecal samples.
“We are ecstatic about the amount of data we collected in such a
short period of time,” Brad told me. “If we would have had 21 days
instead of 10, just think what we could have done.”
Tagging the whales with a dart, which penetrates the skin, has
been controversial among whale observers. Some contend that we
already know that the whales spend time in the Pacific Ocean, and
maybe that’s enough.
But Brad says many detailed findings from the past three months
were never known before — such as how much time the whales spend
off the continental shelf and how much time they spend in and
around canyons at the edge of the shelf.
The sampling of fish scales and fish tissues should reveal not
only the species of fish, but also specific stocks of salmon as
well as their age, Brad said.
“Are they actually targeting the larger and older fish?” he
wondered. “Some fish are resident on the continental shelf. Are
they targeting those? Are they going after the ones they can easily
detect, which means not going after the smaller fish?”
The cruise also collected all kinds of information about the
ecosystem, ranging from ocean depths to zooplankton to the kinds of
birds seen in the area. All that information will feed into a
description of the essential habitat the whales need during their
winter travels.
During the cruise, another whale, L-88, a 20-year-old male named
Wave Walker, was tagged as an “insurance policy” to allow the
whales to be tracked if K-25’s transmitter failed. A shorter dart
was used on L-88, and the tag apparently fell off about a week
later.
The ocean environment is very different from Puget Sound, where
the habits of the whales are well known, Brad explained. In the San
Juan Islands, groups of whales are rarely far apart compared to the
scale of the ocean, he noted.
In the ocean, the orcas were generally grouped up during resting
periods. Sometimes Ks and Ls were together; other times they were
apart. When they were foraging, however, the individual animals
might be spread out for miles.
Brad said he expects to put the new information into some kind
of agency report, probably followed by a peer-reviewed journal
article.
“We have put a lot of time and effort to get to this point,” he
said, adding that the researchers feel a sense of accomplishment
now that the effort has paid off.
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