Alaska Fish & Wildlife News
September 2009
Net-Wielding Researchers
Catch Rare Seabirds
“Two Kittlitz’s, 20 meters, escape diving.”
Acting as spotters, Nick Hatch and Sarah Schoen stand in the bow of the research vessel Curlew on an overcast July afternoon, calling out birds as we chug north from Yakutat. They’ve spotted Kittlitz’s murrelets, one of the rarest seabirds in the world and one of the most difficult to study. Descriptions of the species are checkered with “unknown” and “probably.”
The two avian technicians are part of a team heading for Icy Bay, an isolated, well-named bay on the Gulf of Alaska halfway between Juneau and Anchorage. The en-route survey is just one aspect of a project that also includes catching and banding the rare seabirds, collecting genetic and biological samples, and equipping some with tracking devices and monitoring their behaviors. Although I coordinate the wildlife viewing program for the Alaska Department of Fish and Game, I’m participating as a volunteer, as are several others throughout the capture trip.
The Icy Bay project seeks to discover the status of these birds in Icy Bay and what might be influencing them. The project includes gathering basic life history information, such as how many birds attempt to nest and what the chicks do when they leave the nest. Icy Bay is important because of the high concentration of Kittlitz’s murrelets there during breeding season. It’s the only place where they outnumber all other diving seabirds. Since the study started in 2002, researchers have observed a 50 percent drop in population in six years – which makes learning about all those “unknown” and “probably” facets of these birds’ lives increasingly important.
The project is a partnership between a number of agencies and the US Fish and Wildlife Service: the National Park Service, the Colorado Division of Wildlife, US Geological Survey, University of Alaska Southeast, Alaska Department of Fish and Game, Oregon State University, and the US Forest Service. A mix of professional paid researchers and volunteers comprise the team, which is led by Michelle Kissling of the USFWS.
The Curlew is following a survey route established in 1991. The spotters identify any species of bird, their distance from the boat, and behavior such as flying or diving. In the distance, the chunky silhouettes of murrelets are distinctive from other seabirds. Two species of murrelets occur here, adding to the challenge: Kittlitz’s (Brachyramphus brevirostris) and their cousins marbled murrelets (Brachyramphus marmoratus). In the distance it’s impossible to tell the two apart, so the surveyors just call out “Brachyramphus species” to avoid misidentifications. Closer in, by the end of the day even I’m able to start telling them apart. The coloration is different between the two species. In good lighting, marbled murrelets are a dark chocolaty brown while Kittlitz’s are lighter, with more golden brown flecks. When they fly, only the Kittlitz’s murrelets have white outer tail feathers on their stubby tails. When flying directly away, marbled murrelets’ tails are solidly dark and they have two distinct white lines running up their flanks.
We pass through one section of rocky shoreline where we see murrelets, many of them Kittlitz’s, sprinkled everywhere across the water – two here, three there, sometimes groups of seven or eight, diving with a flip of half-open wings as the boat approaches. Others fly; with their thick bodies and narrow wings, they have trouble lifting off on this windless day, sometimes bouncing on their bellies across the waves a few times. These birds swim underwater with their wings and are powerful flyers as well, often averaging speeds of 60 miles an hour when commuting to nest sites.
The survey is just the start of the trip. For the next week our group will spend nights zipping around in inflatable Zodiacs trying to catch birds. Two more groups will follow ours. In May, the first capture trip of the season, Kissling outfitted a number of birds with radio transmitters to aid in finding nests to monitor and to locate the birds throughout the nesting season. Nearly every day we’re out Kissling takes off in a small charter plane to fly above Icy Bay, the Malaspina Glacier, and across the face of Mt. St. Elias, listening on headphones for the beeps that reveal where one of the secretive birds is spending its time. Or, because there are two peregrine falcon aeries and some bald eagles around the bay, if its time is up.
Our first full day in Icy Bay the group splits in two, half surveying a route started in 2002 that criss-crosses Icy Bay. After another telemetry flight, Kissling takes the rest of us to find a transmitter that indicated a dead murrelet. She suspects the bird fell prey to one of the peregrines. She wants to see if we can find the transmitter and possibly pick up some feather specimens.
We slither up a steep scree slope to the more solid ground where the alders start. After a few false turns blocked by small cliffs and some time figuring out how the signal is bouncing, we discover a pile of feathers on a small outcropping. I’m surprised by how many feathers remain on the ground. They’re snowy white, some with gold or brown flecks on the tips – Kittlitz’s murrelet. Kissling says it’s most likely a peregrine plucking post, where the falcon strips its prey of feathers before eating it. They tend to be tidier than bald eagles, which also prey on Kittlitz’s murrelets in Icy Bay. The transmitter sits along the edge of the feather ring like an alien seed pod, sleek and translucent black with a long, thin antenna at one end. One question answered: peregrines are eating adult Kittlitz’s murrelets.
The radio transmitter aspect of the project has yielded important information. Kissling has found that the number of adults eaten by birds of prey during the breeding season is relatively high in Icy Bay, 11 percent. The radio-tagged murrelets also show a low rate of nesting attempts, and an even lower rate of successfully fledging chicks. This low success in addition to the number of adults taken by predators could be part of the reason for the decline.
During the breeding season the pigeon-sized Kittlitz’s murrelets chase fish in fjords near tidewater glaciers. They nest on slopes recently unveiled by receding glaciers, sometimes even nesting on the glaciers themselves. Where they spend the winter is still a mystery, although some chance sightings indicate they probably go out on the open ocean. Do chicks on their first voyage from the nest stay in Icy Bay before heading out to sea? For how long? Do adults disperse in the open ocean, or do they congregate in some unknown location? Such questions become even more important when populations seem to be decreasing.
In May, Icy Bay lives up to its name. When the tides and winds combine, icebergs from the glaciers at the head of the bay choke the waterway. In July, the icebergs seem more benign and scenic, scattered widely across the milky blue water until you start approaching the glaciers. At least they do during the day while we practice our nighttime capture techniques on plastic bottles. In the dark by spotlight, they jump up in front of the Zodiac a little faster.
The capture teams head out about 11:00pm on these short Alaska summer nights. Each boat has a two-person team, a netter and a driver. Both carry spotlights to scan the water for resting Kittlitz’s murrelets. Spotlighted in the dark, Kittlitz’s murrelets look salt-and-peppery, while marbled murrelets look more solidly dark. Unlike land birds, the Kittlitz’s murrelets don’t have reflective eyes, so you can’t use the glint of eye shine to pinpoint a bird. Even knowing this, every sparkle from a wave crest makes me pause for a second. There are also a surprising number of ice bits sculpted by wind and water to look exactly like murrelets until I almost scoop them into the net. Orange is the theme of the evening—orange Zodiac, orange mustang survival suits, orange rubber gloves to keep the icy water from numbing my hands quite as fast.
When a bird is spotted, whoever sees it calls it out so the other person can get a spotlight on it. If possible, the driver zips around upwind for a better position. Nick Hatch is driving our boat, so he keeps one spotlight on the bird while I switch off my spotlight and drop to my knees in the bottom of the bouncing Zodiac, net ready. The nets are salmon dipnets about three feet across. If the birds don’t escape before I’m in range, I pick one and try to scoop it up as the driver slows suddenly. If it’s windy, the birds fly off the water easily, rapidly diminishing into the night. During the breeding season, sometimes mimicking the murrelets’ sad-sounding honking will lure another bird back, but this late in the season none of them give a backward glance. Sometimes birds will dive, which often gives me a second or third chance if I missed (which happens frequently—they’re fast!). The protocol for the project calls for no more than three attempts to try and limit the stress on the birds.
Once a bird is netted, the best method is to hold the net off the bottom of the Zodiac so the driver can reach in to untangle the bird. Hatch puts the bird into a mesh bag for restraint, so it won’t flail around in the cardboard carrying box and injure itself. The boxes look like large carryout boxes with handles. We try to stay within 15 minutes or so of the Curlew to minimize handling time, but if another bird is encountered on the way in, there’s time to try to catch that one too. The capture boats deliver the bird to the Curlew, and then roar back off into the night to find more. There’s too much daylight to capture at all in June. By mid-July, there’s a limited amount of darkness that works for capturing. Cloudy nights are best, since they hold off the predawn light longer. On a clear night by 3:00am it’s light enough that the birds can see the boat coming and lift off before there’s even a sliver of a chance of catching them. Cloud cover can stretch that cutoff time by half an hour or more.
Once on board, Kissling processes the birds as quickly as possible. I held the birds for processing a couple nights. The doors to the Curlew’s galley stand open to keep temperature cool, so I wear several layers. Kittlitz’s murrelets are well-suited to diving and swimming in glacial meltwater, with half-inch of thick down protected by oil on their feathers so efficient sometimes they seem like they were never even in the water. Overheating during handling is a serious concern. Some accept the handling docilely, others hiss or honk or even bite in irritation when first removed from the bag. The birds are fitted with a hood to keep them calm. Sometimes as I turn one I can feel it blinking against the hood.
As holder, I keep the bird restrained for the different steps of processing. Before it’s out of the bag I weigh it. Once removed from the bag, Kissling places an identification band on its leg. She snips the end of a wing feather for Nick Hatch’s graduate work, looking at stable isotope signatures in the feathers. As I shift my grip to flip the bird over, sometimes I can feel its heartbeat. I turn the bird and Kissling photographs the belly to see how far the speckling extends into the crisp white. She checks for a brood patch, the bare patch of skin a nesting bird keeps in contact with the eggs to incubate them. Since both parents take turns, both have brood patches. She pulls a few feathers from the belly for more isotope samples. The birds molt their body feathers to change into breeding plumage in the spring, but not the wing feathers, so we can get two samples from different time periods from one bird.
Next I open one wing and stabilize it for a blood sample. The blood samples are used to determine the sex of the bird, to test for mercury levels, to test stress levels on the spot, and for genetic samples. I keep my fingers under their feet so they have something to push against and feel more secure during this portion. Their webbed feet feel like warm, paper-thin leather. Once the checklist is complete, the hood comes off and I take the bird outside to the railing for release. Some birds sit in my hand for a few seconds. Gently bobbing them up and down reminds them to open their wings. Some fly a short way and plop onto the water, but most fly off into the night.
The leg bands will help for future capture sessions. Recapturing banded birds allows researchers to estimate the total population size. At the end of the field season, Kissling reported the final numbers from the capture trips.
“Overall, we had a really productive May capture trip—138 Kittlitz’s murrelets, including five recaptures. Our July trip was less productive, with 71 Kittlitz’s murrelets and one recapture, due to really heavy winds and seriously thick fog.”
Kissling also says, “There are two more years of funding to estimate survival and other demographic parameters.” Which means more time to search for answers, from the deceptively simple “where do they go?” to the more complex questions of how the mysterious Kittlitz’s murrelet, in this corner of Alaska where Mt. St. Elias stands sentinel, will fare in the long run.
Beth Peluso is a writer and artist in Juneau. She coordinates the wildlife viewing program for the Alaska Department of Fish and Game.
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