Back in 1812, Russian fur traders established Fort Ross on California’s rugged coast, harvesting colossal redwood trees to construct their settlement. Fast forward over two centuries, and what was once a logged area has transformed. The redwood grove now thrives as a state park, its forest floor covered in ferns and a gentle creek flowing below, evoking the serene atmosphere of an ancient, old-growth forest.
However, a critical question remains: Is this revitalized habitat truly suitable for the marbled murrelet? This fascinating seabird, no bigger than a robin, is famously unique, journeying inland each year to lay a single egg on a high, sturdy branch deep within the redwood canopy. Its numbers in the region have plummeted, making understanding its habitat needs more urgent than ever.
To unravel this mystery and track these elusive birds, scientists are now deploying cutting-edge technology, including artificial intelligence, to pinpoint their locations more effectively.
According to William O’Brien, a wildlife biologist leading this research, the marbled murrelet, affectionately known as ‘mamu,’ seeks out specific nesting spots: ‘an old-growth tree with a large-diameter branch with accumulated debris or moss built up on them.’ These high-canopy nests offer crucial protection from strong winds and extreme temperatures, providing the dark, moist conditions the birds prefer. It’s a truly remarkable adaptation, as the mamu is the only seabird known to nest in the forests of the contiguous United States.
During spring and summer, when breeding season begins, these dedicated birds embark on journeys 30 to 40 miles or more inland. Both parents share the responsibility of incubating their single egg. Once the chick hatches, they diligently fly back and forth to the ocean, bringing fish to their hungry offspring up to eight times a day.
After about a month, the chick sheds its soft downy feathers, revealing its adult plumage. Then, without a single practice flight, this incredible fledgling instinctively navigates the dense forest canopy to find its way to the ocean. How it achieves this feat remains largely unknown, earning the murrelet the fitting title of ‘enigma of the Pacific.’ Early loggers, who often caught glimpses of the birds darting through mist-shrouded redwood crowns, aptly nicknamed them ‘fog larks.’
Sadly, this enigmatic bird is facing a grim reality. Federally, the marbled murrelet is classified as a threatened species across the Lower 48 states, with a population of approximately 23,000. In California, Oregon, and Washington, its situation is even more critical, earning it an endangered designation. While Alaska still boasts healthy populations, the decline elsewhere is stark.
Scott Pearson, a senior research scientist with the Washington Department of Fish and Wildlife, has observed a dramatic drop in murrelet numbers over two decades. In northern Washington alone, the population has dwindled from 10,000 to a mere 4,500 birds.
A significant factor in the murrelet’s decline, according to Mr. Pearson, is the collapse of key fish populations, such as the eulachon, a species rich in vital oils. But marine threats aren’t the only concern; the birds also face legislative challenges.
The murrelet’s protection is currently under review, with the Trump administration proposing amendments to the Endangered Species Act. These changes would remove ‘harm to habitat’ as a basis for protecting species. Officials argue that the original law was intended to prevent direct harm, like killing or capturing animals, not to regulate habitat modifications. However, critics view this as an attempt to accelerate drilling, logging, and development by reducing environmental regulations.
Should these changes be enacted, a crucial, long-standing defense against extinction—the protection of critical habitats—would be eliminated. Noah Greenwald of the Center for Biological Diversity warns that this would be ‘very detrimental’ to the marbled murrelet, which relies heavily on its old-growth forest home for survival. The U.S. Fish and Wildlife Service, when asked for comment, referred only to the proposed changes without further explanation.
Despite these policy threats, a December report from the U.S. Fish and Wildlife Service noted stable murrelet populations in some areas, ultimately concluding that the seabird should maintain its protected status. Furthermore, the U.S. Court of Appeals for the Ninth Circuit recently affirmed a lower court’s decision, confirming that logging old-growth trees in Oregon’s Elliott State Forest would indeed violate the Endangered Species Act by harming murrelets.
Meanwhile, in Oregon, two long-term studies are shedding light on the elusive birds’ behavior. Matthew G. Betts, a professor of landscape ecology at Oregon State University, revealed that murrelets prefer to nest in communities, with younger birds seeking out the presence of more experienced individuals. This insight is crucial for effective forest protection strategies.
Researchers also discovered that murrelets actively avoid nesting near forest edges adjacent to roads or clear-cut logging areas, a defense against predators. Dr. Betts noted, ‘We’ve seen red tail hawks on camera coming in and eating chicks,’ highlighting the vulnerability of these nesting sites.
As the murrelet’s natural world shrinks, vital research at Fort Ross is underway to find and safeguard alternative habitats. The Save the Redwoods League, a dedicated nonprofit, owns the Sonoma Coast Redwoods and is investing in studies to determine how readily these birds might adapt to nesting in second-growth trees.
The historical context of their decline is stark: over 150 years ago, widespread clear-cutting by timber companies obliterated roughly 95 percent of old-growth redwoods along the Pacific Coast. This destruction annihilated the vast majority of the murrelets’ breeding grounds in California. While redwoods, with their immense height and large branches, are preferred, these birds also frequently nest in fir and spruce trees.
Beyond habitat loss, other significant threats plague the murrelet. Catastrophic events like the 1989 Exxon Valdez oil spill severely impacted populations. Moreover, the birds are vulnerable to entanglement in fishing nets as they agilely pursue fish underwater. Closer to their forest nests, predators like ravens and Steller’s jays pose a threat, often raiding nests for their large eggs. Conservationists attribute an increase in these predatory incursions to human activity, specifically blaming picnickers for leaving food waste behind. Parks such as Big Basin Redwoods State Park are actively campaigning to encourage visitors to keep their sites spotless to protect the murrelets.
Portia Halbert, a senior environmental scientist for California State Parks, underscores the human role in this predation: ‘We provide food to their predators and increase the number of their predators. Even a crumb can support the predators that will contribute to the death of a marbled murrelet.’
Climate change introduces another grave threat: wildfires. Redwood forests, typically cool and damp rainforests, once rarely experienced intense fires, their thick bark providing natural protection. However, a warming climate is drying these ancient woods, making them increasingly vulnerable. The CZU fire, sparked by an unprecedented dry lightning storm during a heat wave, raged through Big Basin Redwoods State Park, incinerating 97 percent of the park and severely damaging half of its redwoods. While most trees are now regrowing, the aftermath presents new challenges.
The blueblossom plant (Ceanothus thyrsiflorus), which contains flammable oils, has proliferated across the burned landscape, creating a dangerous new fuel source. Ms. Halbert fears ‘another catastrophic fire,’ warning that repeated intense burns could prevent redwoods from recovering, leading to ‘ecosystem type conversion’—the transformation of a majestic redwood forest into shrubland.
Remarkably, amidst this devastation, researchers discovered California’s first new murrelet nest in 30 years within a fire-damaged but surviving tree. This discovery even led to the capture of a rare video showing a chick embarking on its maiden voyage to the sea.
The murrelet’s dual existence—thriving in both marine and forest environments—makes it uniquely vulnerable. It spends three-quarters of the year at sea, deftly diving for sardines and anchovies, using its wings like flippers to hunt underwater. This incredible versatility, shared by only a few other birds like puffins and guillemots, also exposes it to a wider range of threats.
Ocean warming and shifting currents are disrupting fish populations, directly impacting the murrelet’s vital food supply. A prime example is ‘the Blob,’ a large mass of warm water that plagued the Pacific off the West Coast from 2013 to 2016. ‘The Blob is a pocket of hot water that prevents upwelling, which brings in all of the nutrients and things that small fish like to eat,’ explained Ms. Halbert, illustrating how such marine phenomena starve the murrelets’ prey.
Given the multitude of external dangers, conservationists recognize that simply safeguarding existing old-growth nesting sites in parks is insufficient. A broader strategy is essential, requiring the identification and protection of additional suitable habitats to ensure the species’ long-term survival.
Studying murrelets is notoriously challenging. Their nests are incredibly well-concealed, and the birds themselves are masters of camouflage. For decades, their nesting habits remained a mystery, so much so that the Audubon Society once offered a $100 reward for locating a nest. It wasn’t until 1974 that an arborist in Big Basin stumbled upon a ‘fluffball’—a baby murrelet—revealing their preferred redwood canopy homes.
Even today, biologists undergo a week of specialized training to accurately identify these birds during surveys, as they’re difficult to spot amidst the dense branches at dawn and dusk, when the birds are most active and vocal. Researchers also track them from boats and aircraft out at sea.
However, modern technology is revolutionizing murrelet research. At Fort Ross, automated recording units equipped with artificial intelligence are being deployed in redwood groves. These devices capture vast amounts of audio and video data, which AI then sifts through to detect the distinct calls of the murrelets, promising unprecedented insights into their secretive lives.
Ultimately, the path to recovery for the marbled murrelet is a long one. As Mr. O’Brien emphasizes, ‘We’re talking on the scale of centuries for these trees to provide the large nesting platforms that murrelets need.’ It’s a testament to the enduring power of nature and the patience required for true conservation.