By Meghan Walker To tag or not to tag? Puget Sound orcas keep researchers on their toes

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1 By Meghan Walker To tag or not to tag? Puget Sound orcas keep researchers on their toes For the past few weeks, Ken Balcomb has been putting up posters on docks at marinas along the California coastline, requesting orca-sighting reports. It may seem archaic, akin to a kid putting up a lost cat poster on a telephone pole. But, Balcomb says it works. Tourists aren t the only people hungry for an orca sighting. Balcomb is a senior scientist at the Center for Whale Research in Friday Harbor on San Juan Island. He s been studying whales since 1963, and right now, he s eagerly waiting for a sighting off the coast of northern California near Monterey. Orcas have been under close surveillance by researchers like Balcomb for decades. The problem is that Puget Sound orcas go untracked for many months out of the year. Orcas are active creatures and explore much of the western coast between November and April, but researchers can t say exactly where they go. These iconic killer whales are endangered, and pinning down their winter travels will help Balcomb and others create protected areas along the coast, where they spend half the year. Tracking animals is a challenge. Satellite tagging has been gaining momentum in recent years, but there are significant pros and cons to the method. One researcher who has used satellite tagging for years is Russ Andrews, a biologist who has used tags to track false killer whales in Alaska and Hawaii. It s not a simple maneuver to attach a transmitter to a whale. So, they use a dart gun. Imagine being on a boat and sidling up to a whale the size of a truck, bobbing up and down, with waves obstructing the target. This is the challenge for Andrews and his team, who have to wait for the right moment to shoot a whale, usually in its dorsal fin. A successful shot means the transmitter may stick for one to three months. An unsuccessful shot could mean an injured whale, and that s exactly what worries Balcomb. Balcomb says the transmitter s life spans are too short. He also thinks they re too big, too clunky, and likely to be too injurious to the whales. Balcomb says better tagging technology is just around the corner. He says smaller tags with longer life spans will be developed. We don t want to injure the whales unnecessarily. The concern about tagging injury isn t unfounded. Penguins have been tagged for over a decade, and the results are troubling. Tagging has been associated with decreased lifespan and decreased breeding success. According to an article published in Nature in January, after 10 years, tagged birds had 16 percent lower survival and 39 percent fewer chicks. Given those odds, it s no surprise some researchers are wary of tagging. Balcomb is looking for the L pod of Puget Sound s Southern Resident orcas. The Southern Residents consist of three groups; the J, K and L pods. In all, there are about 85

2 orcas that make up the three pods. J and K have about 20 whales each; L pod numbers about 40. Each pod travels as a unit, and is known to spend most of each year in Puget Sound. They re spotted almost daily in Haro Straits, right off San Juan Island s Lime Kiln Park, where they snack on salmon. Summer whale watching is easy, when all three Southern Resident orca pods splash around in Puget Sound. The whale-watching industry keeps a close eye on the J, K and L from spring to fall. The problem is winter. While the J and K pods mostly stick around Puget Sound, the L pod cruises south, away from the attentive eye of the whale watchers. They move like the clouds, so the pattern is this one year and that another year, said Balcomb. He said it would be valuable to know what they re doing; what species they re eating, how long they re staying, and how important that is to their survival. Balcomb said that unless tagging offers up that new information, it won t tell them anything new. Balcomb is convinced that Andrews method isn t right for the J, K and L pods. However, a Seattle scientist hopes to use the method on the Southern Residents. Brad Hanson is a wildlife biologist for the National Oceanic and Atmospheric Administration, or NOAA. He works with the Northwest Fisheries Science Center, and has spent years studying the migration of whales in the Pacific Ocean. His work is now focused on learning more about the winter migration of the Southern Residents. While the whales are under close surveillance from spring through late fall and indeed their every move is seen daily by thousands of whale watch boats - little is known about their migration south for the winter. Whales go where the food is. In the winter, that means the L pod will travel down to the California coastline seeking salmon. From their Puget Sound departure in late November through their return in March, the L pod may very likely be at the mouths of the Columbia River in Oregon or at the Sacramento River in California. Or, they might be deep-sea diving off the California coast. There s even a chance they re doing laps just off the sandy beaches of Florence, Oregon. Because food determines the pod s path, researchers can only guess (and rely on sightings) to track them down. Hanson has some allies when it comes to tagging. Robin Baird is a scientist with Cascadia Research. He s been working with Hanson, following the Southern Residents around Puget Sound throughout the summer and autumn months. He says the whales typically eat two species of salmon in the Puget Sound: chinook in the summer and chum in the fall. Due to the difficulty of winter tracking, Baird and other researchers still don t know what the whales eat in the winters.

3 Hanson and Baird understand the risks of tagging. They, too, want to avoid injury to the whales. The intent is to further protect the species, and tagging seems to be the best solution. Baird thinks Hanson s tracking method will work. Tagging would give researchers the hard evidence they need to designate new critical habitat zones for orcas. If areas like the Sacramento and Columbia River mouths become protected, it would promote salmon preservation in those areas. Knowing where the animals spend their time is one thing and then being able to confirm what they re eating when they re in that area is another, says Baird. The critical habitat designation would also prevent military testing in those areas. Baird says an incident in 2003 in Puget Sound is a perfect example of why whales need critical habitats. The USS Shoup is a navy guided missile destroyer that sent orcas fleeing in the Haro Straits nearly seven years ago. The reason? The USS Shoup was using sonar pulsing during a training exercise. The blasts were so overwhelming it caused the Southern Residents to scatter. Since then, navy sonar use has been limited because of the critical habitat zoning in Puget Sound. Baird says that distinction must be made along areas of the West Coast where the L pod hangs out in the winter to keep the whales safe. Satellite tagging would give researchers that hard evidence they need to establish new zoning for orcas. However, Balcomb says there is photographic evidence that tagging leads to open wounds and unsightly scarring. On the other hand, Baird says there is also photographic proof that whales fared just fine after being tagged. What it comes down to is, what is the best available method and what are the costs and risks associated with that method, Baird explains. We know the risks are minimal, we have high re-sighting rates, and it s not affecting mortality. Risks aside, Baird is convinced that sightings aren t enough to gain crucial information about winter migration. For one, Baird says they move quite a bit in a day. A sighting in the morning could be useless by mid-afternoon; orcas travel up to 50 miles in a day. Another drawback to sightings is the poor weather during winter months along the coast. Even if a sighting occurs, the weather can keep researchers land-locked for days. All whale researchers hope to see extended protection for the Southern Residents. Hanson has already applied for a tagging permit. NOAA is now reviewing the proposal and comments submitted by Balcomb and other anti-tagging researchers to weigh the issue. Until then, the endangered Southern Residents continue to keep researchers guessing through the winter months. The Sound of Whales: Tracking with Acoustics

4 Sightings and tagging aren t the only ways researchers are tracking whales. Scott Veirs is founder of Beam Reach, an educational sailing program that takes college students on ten-week trips tracking orcas in Puget Sound. Veirs has a different tracking approach: sound. Orcas are extremely vocal creatures. Using calls, clicks and whistles, orcas communicate constantly with one another. Veirs s program uses five hydrophones scattered around Puget Sound to record the whales. The subtle differences in the whale sounds are hard to pick up on, but Veirs has an ear for it. He plays a recording of an orca using clicks to echolocate salmon. They send out a little click and listen to it echo off a fish bladder, explains Veirs. He said chinook bladders are about the size of your fist. The sound bounces off that bubble of air, and it comes back and they can hear that echo. Veirs says there s a good amount of evidence that orcas can t only hear it, but they can tell what species of salmon from which it came. The hydrophones are always listening. And, a person is almost always listening. Veirs has a network of scientists and researchers around the sound who tune in. Think of it as aural whale watching. My dad and I have a contest, said Veirs. Val Veirs, Scott s dad, set up a network of computers to detect the whale sounds. Val thinks his web of digital listeners is superior, but Scott says his group of humans is pretty impressive. So far, the computers are winning, but not by much. Veirs said the computers detected the Southern Residents going by Port Townsend about 65 percent of the time, while his human network detected them 55 percent of the time. He said it s not uncommon to get an from a listener who s heard a whale before the automated system catches on. Jeannie, she can listen in her sleep, jokes Scott. Jeannie Hyde lives on San Juan Island, and has an ear for the subtleties of whale calls despite the noise pollution of everyday traffic in Haro Strait. She s an example of someone who will often hear whales when our computers don t detect the calls amidst the ocean noise. Veirs plays a live feed of San Juan Island s Lime Kiln Park hydrophone. It sounds chaotic; the current creates a constant hiss, and every once in awhile, bull kelp knocks the hydrophone around which makes a loud clicking noise. Beam Reach relies heavily on these hydrophones from fall through spring, when whale-watching boats are in their off-season. Indeed, during the summer, they can follow the whale watchers for sightings. But in the winter, the J and K pods are as vocal as ever, and Veirs listens closely for information about their whereabouts.

5 Veirs, a strong proponent of acoustic tracking, has reservations about satellite tagging. He s seen the photos depicting scar tissue and the miscalculated shots that result in injury to the whale. However, he knows the importance of understanding and designating critical habitats for orcas along the west coast. For proponents of non-invasive tracking methods, it would seem Veirs method is the answer for finding Southern Residents during the winter. We haven t fully utilized the power of passive acoustics to understand where killer whales go on the outer coast, says Veirs. He said he hopes to see that change in the future. There are plenty of opportunities that may be cost-effective compared to tagging, that I don t hear people talking about as much as I d like. Veirs plans to keep urging the rest of the whale-tracking community to invest in hydrophones up and down the West Coast. Until then, he and his network of listeners will continue to tune in to the chatter of orcas in Puget Sound.