You don’t realize just how dense the forests on the Oregon Coast are until you try to bushwhack through them.
“This is insane,” said Megan Linke, as she crawled up a steep, slick, moss-covered log to get out of a deep ravine, her foot slipping and threatening to send her sliding back down.
Her team of four field technicians had already spent two hours climbing up and down ravines and crawling through thick stretches of salmonberries, their helmets and safety glasses providing a minimum level of protection against the endless assault of thorny branches. Whenever they stopped, steam rose from them in clouds, a combination of dew and sweat condensing in the chill morning air.
At the top of the ravine, Linke pulled out her phone to look at the map of their progress, only to find they’d barely progressed across the undulating topography.
“Oh yeah, we didn’t go far at all,” she said with a laugh.
Of course, this wasn’t a pleasure hike. These researchers were looking for the marbled murrelet, a bird so elusive it’s known as “the enigma of the Pacific.”
The field crew can bushwhack through salmonberry brambles for hours, searching for the radio frequency of the bird on the nest.
Stephani Gordon / OPB
Marbled murrelets nest in the canopy of the Northwest’s coastal, old-growth forests, which puts them in the nexus of a long-running battle between environmentalists and the timber industry. They’ve been listed as threatened under the Endangered Species Act since 1992, but their numbers have continued to drop across the region. And it’s hard to come up with a plan to save them when we know so little about the bird.
“They are a species that, because they’re so challenging to study, we just don’t have really good information on them,” said Jim Rivers, an assistant professor of wildlife ecology at Oregon State University. “And that hinders their conservation and also hinders planning for timber management of our coastal forests, which are really key to Oregon’s economy.”
Enter the Oregon Marbled Murrelet Project. It’s a team of around 20 scientists and field crew — Rivers is the principal investigator — based out of Oregon State University’s College of Forestry. With backing from the state, the logging industry and conservation groups, the things the project learns about how different threats like logging and climate change affect marbled murrelets could mean the difference between coming up with a plan to save them, and the species disappearing without a trace.
“The Oregon Marbled Murrelet Project’s core goals are to determine where the birds are nesting, how successful they are, and then what are the key sources of mortality for nests,” said Rivers.
These seem like basic things we ought to know about all the birds in North America. But they aren’t known when it comes to the marbled murrelet.
Related to seabirds like murres and puffins, marbled murrelets are members of the auk family. But while they spend most their lives at sea, early ornithologists couldn’t find them nesting with other seabirds.
“They’ve always been a mystery,” said Kim Nelson, a wildlife biologist at Oregon State University and a co-principal investigator with the project. She is a leading expert on marbled murrelets. “In the 1930s and 40s, they suspected that murrelets might nest inland because they hadn’t found their nests on the offshore rocks. But it wasn’t until 1974, when a tree climber was climbing up a tree to cut off a branch in a campground, and he found a murrelet chick on a nest.”
That first nest was found in California. Nelson’s team didn’t find a nest in Oregon until 1990, although she’s quick to point out that if those early ornithologists had just asked the native tribes that live on the coast, they could have solved their mystery much sooner. “They revered murrelets, and they knew they lived in the forest,” she said.
But it wasn’t just that they are the rare seabird that nested inland. They actually don’t build a nest at all. They lay their egg on beds of moss on large horizontal branches. Which means they mostly nest in large, old-growth trees, a discovery that had ramifications that echoed far beyond ornithology conferences.
Marbled murrelets don't build nests but instead lay their eggs in moss on large branches in old-growth trees.
Stephani Gordon / OPB
This was all taking place during a battle known as the Timber Wars — a fight over whether to log or preserve the last of the Northwest’s old growth trees. While environmentalists had mostly failed to stop logging with protests and legal fights over the trees themselves, by the early 1990s they managed to protect large swathes of forest by proving they were necessary habitat for the survival of the northern spotted owl.
The discovery that another species needed old growth trees to survive — and lived in some forests where the owl was absent — was like avian backup flying in to join the conservationist’s side in court.
So environmentalists fought to get the murrelet listed as threatened in 1992, and they have been able to use the Endangered Species Act and other environmental laws to severely limit logging of older forests in California, Oregon and Washington ever since, making the bird as controversial as the spotted owl in many places.
But while protecting the birds and their habitat has been an economic hit to the timber industry and some timber-dependent communities, the murrelet’s population has continued to decline, meaning it’s in the interests of both environmentalists and the timber industry to figure out the exact threats facing the bird, in order to best preserve it. Which is why both back the Oregon Marbled Murrelet Project’s quest to understand the nesting needs of murrelets.
This is a story about how hard science can be. It’s like, take the needle in the haystack metaphor, but then enlarge the haystack until it is several miles of dense, thorn-filled forest, and imagine that your needle is a small bird on a branch 100 feet in the air.
And searching the forest isn’t even the first step in finding this bird. So let’s start from the beginning.
From their small inflatable boat, the capture team scans for murrelets floating on the open ocean.
Stephani Gordon / OPB
Even though they’re looking for nests in forests, this search begins at sea, because that’s where the researchers can more easily find the birds — and also because the researchers don’t want to assume where the birds nest, so finding them on the ocean means they can follow the birds wherever they nest, even if that happens to be non-old-growth forests.
The project has a short window near the start of mating season — typically the month of May — to find enough birds to follow for the summer. So a crew leaves the Newport Marina in a research boat every night the seas are calm enough to sail, and heads out to spots several miles offshore where murrelets tend to forage and rest. And they go at night, so they can sneak up on the birds.
“We have a capture crew that we contract with who come up from California,” Rivers said. “And it sounds kind of crazy, but we put them into a 14-foot inflatable Zodiac and send them out on the ocean.”
As the Zodiac roamed the dark waves the night we went out, Darrell Whitworth, a wildlife biologist from the California Institute of Environmental Studies, stood in the boat and scanned the ocean with a powerful spotlight, looking for the light body of a floating murrelet. Rough ocean conditions had kept the research crew mostly landlocked for weeks. So now that the sea had calmed enough to go out, everyone was on edge to salvage the season.
Then he saw it: a small white dot bobbing on the surface. The bird froze for a second in the spotlight, and then dove. Whitworth started tracking it as it swam underwater, frantically gesturing to the driver which way to go.
“Using hand directions, I’m telling the driver, ‘that way, that way,’” explained Whitworth afterward. “And you try to get the boat to the point where the bird comes up and then you just scoop it right out” with a net.
It’s an artform. Whitworth’s team literally travels around the world, working for different murrelet researchers.
The capture crew brought the bird back to the ship in the same type of box you take your cat to the veterinary in. And their tides seemed to turn this night, as they brought in bird after bird.
Field technicians measure the captured marbled murrelets, assess their health and take genetic samples before attaching small radio transmitters and releasing the birds.
Stephani Gordon / OPB
In the dark cabin of the ship, the field technicians have an hour to assess the health of each bird, measuring things like weight and temperature, and take genetic samples.
Thanks to early research, researchers know that the fate of marbled murrelets depends on preserving the old growth forest they nest in. But the Oregon Marbled Murrelet Project is learning that the bird’s fate is just as tied to ocean conditions.
In the first year of the project, they captured dozens of the birds at sea, but none of them went on to breed. And the scientists think one reason is the many ways climate change and fishing has disrupted the ocean food chain.
“Herring and anchovy have pretty much disappeared from the oceans,” said Nelson. “And so murrelets are feeding on fish that’re lower quality. And so that can have an impact on nesting success.”
So another thing they’re tracking is what the birds eat and what effects that has on their health and reproduction success.
After the health assessment, they attached a small transmitter tag that will allow them to track the bird using what’s called radio telemetry (the tag eventually falls off on its own), and they released the murrelet back into the ocean.
Every morning, field technicians drive along the coast, recording the presence and location of the murrelets they've tagged out on the ocean. Once a bird starts going missing from the ocean every other day, they assume it has started to nest and start searching for it in the forests.
Stephani Gordon / OPB
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The dawn brings a changing of the guard. As the overnight crew unloaded from the boat and headed back to the shared houses to crash, Jason Piasecki and Lindsay Adrean headed out to Newport’s South Jetty with a large, handheld antenna. They climbed a dune near the jetty, where Paisecki set up a tripod for the antenna and Adrean started scanning the ocean with binoculars.
“Every morning we have technicians up and down our coast listening to all our birds,” said Adrean, a faculty research assistant, while Piasecki scanned through the different transmitter frequencies with the antenna. “They spend most their time on the water either foraging or resting.”
Their scan complete, the two loaded back into a truck and headed south, stopping at various beaches to repeat the process.
“439 is back on the water today,” Piasecki said, removing his headphones.
When they hear each bird’s beep, they try to triangulate its position. But they’re also making note of when they don’t hear it, because once a pair of murrelets have laid an egg, they take turns incubating it, trading off every morning. So the technicians are listening for birds that go missing every other day, because that could mean they’ve produced an egg.
“So we’re able to pick up that pattern, and it will tell us we need to get the plane to look for the nest,” said Adrean.
The aerial technician Jon Dachenhaus flies inland, searching for the signal from the missing murrelets in the coastal forests.
Stephani Gordon / OPB
“Today we’ll go all the way up to Cape Lookout and circle around,” the aerial technician Jon Dachenhaus told his pilot over the static-riddled channel on a twin turboprop plane, shortly after taking off from the Newport Municipal Airport.
Once they think a bird is nesting inshore, it’s Dachenhaus’s job to fly up and down the coast, scanning with an antenna on the plane for the bird’s transmitter signal.
“Alright, so that’s a bird,” he said, as suddenly a beep appeared over the static. “Ninety left. As much as we can drop in this drainage over here, Brad, let’s do it.”
Marbled murrelets can nest up to 50 miles from the sea.
“We’ve noticed that they like to be down in the drainage in these larger trees, that have flyways for them to come in, to and from the nest,” he said.
The edges of clearcuts pose a particular threat for marbled murrelets nesting nearby, because they open nests up to the eyes of predators like hawks and jays.
Stephani Gordon / OPB
From this bird’s eye view, you see just how much logging has transformed these forests. A mosaic of clearcuts and stands of different aged trees stand out as clear as if they were a patchwork quilt of browns and greens. And the researchers are finding that’s a problem for the birds.
“One of the big concerns with murrelets is edge effects,” said Dachenhaus, looking down as we pass over the edge of a clearcut. “So how close their nests are to clear cuts or stand edges, and how much potential nest predators intrude, now that they have access to areas they formerly didn’t have access to.”
The chicks are camouflaged to blend into their branches, but the project has learned that ravens, jays, and even red-tailed hawks can find them. And it’s not just the chicks that are vulnerable. The adults make up to eight trips a day from nest to ocean and back to bring fish to their chicks, burning massive calories to cover hundreds of miles and risking predators themselves.
There’s little room for error, which means any changes to their ocean food sources or the forest can have outsized impacts.
As the field crew bushwhacks through the dense coastal forest, they stop periodically to scan the canopy with an antenna, hoping to hear the beep that would signal the murrelet's radio transmitter tag is nearby.
Stephani Gordon / OPB
Using the general location Dachenhaus obtained from the air, the ground crew moved in next.
“Not feeling too good about this one,” Megan Linke said as they crossed a stream at the edge of the road before plunging into a seemingly impenetrable wall of salmonberries.
That feeling, of course, would prove prescient.
The team spent several hours plowing through the undergrowth and stopping periodically to listen for the signal from the bird’s transmitter.
But hour after hour, they were met with nothing but static.
The anxiety grew with each passing hour and each passing ridge.
“Let’s do some telemetry here,” Linke said in a patch of salmonberry that looked like any other. “I think this is a good spot. Hopefully we can hear it.”
This time, when Ethan Woodis hoisted his black antenna into the air, they were met with a most unremarkable beep.
“There’s a beep!” exclaimed Nicole DeFelice.
“It’s not on the water!” followed Linke. “We didn’t hike out here for nothing.”
Related: Last Call: Tracking The Sound Of The Spotted Owl’s Extinction
For the next hour, they spread out in every direction, trying to zero in on the signal, until they found a stand of trees where the signal was strongest.
But the bird could be nesting on any branch. The only way to know was to see it fly in or out during its daily commute.
That meant they were going to have to come back every morning in the dark, and spread out around the stand of trees and watch — each crew member staring at a different gap in the foliage for hours.
“We have a gap and you’re trying to get that gap in your whole field of vision,” explained David Bolduc, staring up at the sky.
Murrelets have been clocked going 100 miles per hour. If the gap in the canopy is small, the watchers can blink and miss it. “It takes a second, and then the bird is gone,” Bolduc added.
If they don’t see the bird, they return the next day and pick a different gap to watch.
It took seven trips before they finally saw this bird.
After they have a sense of what branch a bird is nesting on, a climber heads up a neighboring tree, looking for a clear view of the nest. Once they find it, they set up a camera, as well as an antenna that will track the coming and going of the bird. And then another crew monitors the nest, watching as the egg hatches and the chick fledges, until, if no predators come or other disturbances happen, it flies off to live its own life in sea and forest.
A nest cam captures the interchange between a curious and potentially hungry Steller's jay and a chick that fends it off.
Oregon State University
It might seem ridiculous, all these people struggling by boat, by plane and by foot to find a homely seabird that has evolved a peculiar need for big mossy branches.
But the fate of the murrelet will help determine the fate of the Northwest’s older trees.
More than 3 million acres of coastal forests are protected from logging to preserve the bird. Yet the timber industry regularly challenges those protections. And there are still so many questions, like does thinning nearby forests present the same threat as clear-cutting them, and are there other trees or ages of forests that the murrelet might nest in.
“One of the things that was surprising from last year’s efforts was that we found a bird nesting in a big leaf maple, which was the first record for the lower 48 states,” said Rivers. “It kind of confirms what we knew that the birds need large horizontal limbs, but they may be found in other species than just conifer trees. And that’s one of the key reasons why we’re tagging birds [at sea], is because we probably wouldn’t have been looking for a bird going into a tree that wasn’t a conifer tree.”
They’ve also found some birds range much further up and down the coast than they originally thought.
“Having information allows us to have a better idea of what murrelets need and how that can be integrated into management of our coastal forest that allows for timber production as well,” Rivers said. “The murrelet is a bird of two worlds. So having healthy forests and healthy oceans means that we can also have healthy murrelet populations as well.”
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