The ancient murrelet is a small alcid, or auk, and a close relative of the federally threatened marbled murrelet. Although not threatened itself, the ancient murrelet shares several traits with its more imperiled congener. Like the marbled, the ancient is small and discreet, with a low swimming profile. It will spend the winters in the Strait of Juan de Fuca, or near Admiralty Inlet, down in Puget Sound, or in other waters of the Salish Sea. Unlike the marbled, the ancient does not prefer to nest on the high branches of old growth conifers, but in burrows on the ground, or under fallen logs. And unlike the marbled, the ancient is not known to have nested in Washington State for more than a century.

That said, there have been recent if occasional hints of activity: the suggestive presence of adults loafing in the sea near suitable islands off the Washington coast, for example. Sometimes with a young chick in tow. But those islands can be difficult to reach, and so confirmation has remained as elusive as the ancient murrelet itself. 

The murky fortunes of the ancient murrelet and other birds like it came to mind with a recent paper published a couple of weeks ago in the journal Science. A team lead by Alison Johnston, now a quantitative ecologist at the University of St. Andrews in Scotland, had used fourteen years of data from the eBird program at Cornell University to find that three-quarters of 495 bird species in North America, ranging from warblers to hawks to sea ducks to falcons, were declining. 

For Johnston, the paper represented not only years of effort, but also a way to advance, or at least modulate, what was becoming a consistent if perhaps overly broad tale of avian vanishing. Her  paper had followed hard upon an earlier study from 2019, also out of Cornell, on how North America has lost three billion birds since the 1970s, which translated roughly to one-third of all individuals. This affected species across the board. 

“We found 75% of species were declining, but we already basically knew that,” Johnston says. “There are many previous studies, other surveys.” What is notable about this work was its ability to examine those overall declines at fine geographic scales, and in so doing parse their natures. Tens of thousands of participants with eBird provided 36 million observations, from bird counts in neighborhoods, city parks, and more conventionally wild spaces. Compiling all that data allowed Johnston to consider species’ population dynamics at a resolution of 27 square kilometers — an area about eight times the size of Central Park in New York City. 

Previous analyses of bird population trends were often constrained by political boundaries: state lines, county lines, and so on; the dynamics at more biologically relevant scales were, as Johnston says, “mostly invisible.” But in the analysis, Johnston, who first undertook the work while a postdoctoral researcher at Cornell University, was able to divvy species among dominant landscapes over the whole of the continent: Arctic tundra, aridland, forests, grasslands, and wetlands, with another category for birds that were generalists.

The most worrisome finding to come from this new close view of population dynamics was the fact that the rates of decline are generally greatest in areas where species were most abundant.

Doing so allowed her to zero in on habitat-related trends. Broadly, this meant she and her team could effectively slice and dice their results into varying percentages, or trends within trends: 75% of species were declining somewhere in some way, but that did not mean uniform loss necessarily; 97% of species showed, as the authors wrote, “separate areas of significantly increasing and decreasing populations,” going down in some places, but up in others. In sum, roughly two-thirds of species showed declining populations overall. 

The most worrisome finding to come from this new close view of population dynamics was the fact that the rates of decline are generally greatest in areas where species were most abundant. The losses were not merely a question of birds leaving marginal habitats; they were disappearing in places that should have been good for them. “That they’re leaving places where they were really abundant caught our attention," Johnston says. 

That finding in itself, though, is a kind of counterintuitive cause for optimism. “What this did is give us an opportunity to understand the drivers of those declines,” Johnston says. Biologists can know now where a population is increasing or decreasing in a much more detailed way. They can ask why a species might be expanding its range in one place while abandoning another formerly preferred haunt. From there, they can plan strategic conservation actions in areas where those actions have the best chance of making a difference. “For some species,” Johnston says, “that might mean trying to arrest a decline, while for others it might mean helping with a range expansion.” The end result, she argues, is that managers have more knowledge and tools to start a conservation. “It’s a bleak message for the world, definitely,” she says. “But the information will also let people be a lot more forward thinking. This is not the end of the story.” 

For the waterbirds of Puget Sound and the Salish Sea, the national patterns that Johnston and her team found are in many ways recapitulated. Not all birds are represented among the eBird dataset—of the region’s several alcids, for example, the program has trend maps for only marbled murrelets and pigeon guillemots. (Some species, it seems, still need specialists to go out and look for them.) Both are declining both inland and outer coast waters. But there is the occasional bright spot: just this year, biologists acting on a hunch sailed out to a couple of islands just off the Washington coast. After hours of poking around, they found adult ancient murrelets sitting on eggs in several burrows. One adult even had a chick. Is it range expansion? Reclaiming of former territory? At this early stage it is hard to say. But it is something.