After a dry winter and a hot spring that led to begging every storm cloud for a few drops of moisture, it's hard to imagine something that might be more welcome than the sound of a "rain crow." That's the name the yellow-billed cuckoo earned for its habit of issuing a series of guttural, stuttered calls just before rainstorms begin. Renowned naturalist and birder David Allen Sibley transcribes that song as "ku-ku-kddowl-kddowl."
The yellow-billed cuckoo spends winters in Central and South America, then migrates north for a summer range that once swept from Atlantic to Pacific coasts, concentrated in densely vegetated riparian areas. In New Mexico, that means seeking cottonwood stands and willow thickets along the Rio Grande and Gila River. They're one of few bird species that can consume horned caterpillars. While it's unlikely they'd migrate up a shallow creek like the Tesuque or nest in aspen groves, they would also aim their namesake yellow bills for the same culprit that's chewed through the aspen canopy near Hyde Park Road: the tent caterpillar.
"Here's this beautiful bird that has this remarkable journey—a literal journey that it takes—and that is in decline because we've recklessly harmed streamside habitats throughout the Western United States," says Michael Robinson, with the Center for Biological Diversity.
The center first petitioned the US Fish and Wildlife Service to protect yellow-billed cuckoos in 1986. The species was included in a 2011 legal settlement between the center and the service that compelled the federal agency to make decisions on 757 species whose status as endangered had been pending. On July 11, the center notified the Fish and Wildlife Service of its intent to sue the federal agency again, this time for failing to protect critical habitat for the cuckoo in Western waterways.
Riparian habitats have been shrinking in the West, and that habitat loss led to listing the yellow-billed cuckoo, but only its western population as separate and uniquely threatened, compared to its eastern counterparts. That status, gained in 2014, has been challenged by ranching and mining associations and companies, including American Stewards of Liberty, National Cattlemen's Beef Association, Public Lands Council, Arizona Cattlemen's Association, and Arizona Mining Association. On June 26, the service issued notice that it's going to give the petition serious consideration.
The groups argued that there's more riparian habitat than what the US Fish and Wildlife Service accounted for when they decided to list the western yellow-billed cuckoo, and that the western and eastern populations may intermingle.
"The petition brought information that may indicate that that distinction is not as strong as we originally thought," says Jennifer Norris with the Fish and Wildlife Service. "If they're not distinct, then we look at the entire population of yellow-billed cuckoos."
Assessing the population as a whole, rather than unique populations, could shift whether it's considered threatened.
In the West, where water is already limited, conservation advocates argue that increasing demands and decreasing supply through drought have compounded the issues for the bird. Cuckoos can be picky, too, about leaving their nests to travel across breaks in the canopy, Robinson points out, relying instead on contiguous riparian areas.
The agency is in the process of finalizing what it defines as the species' critical habitat, which would designate areas where protective measures could curtail activities like grazing. Another riparian species, the New Mexico meadow jumping mouse, drew ranchers' ire for the fence exclosures constructed to protect its streamside habitat from grazing cattle.
Critical habitat designation has been a long time coming in part because covering nine states is a big project, Norris says, and in part because public review of the draft habitat proposal prompted reports about additional locations for the species in Arizona.
"The places that we were notified that they occurred, they're not the traditional riparian zones. They're more these upland mesquite washes that we think are affected by monsoons," Norris says. "Maybe they're utilizing different types of habitat."
The latest petition suggests the expanded range means the bird might not need listing at all.
"The Service underestimated the amount of suitable habitat, which resulted in its listing and made an inaccurate analysis of threats," Ethan Lane, executive director of National Cattlemen's Beef Association and Public Lands Council, said in a press release. "As a result, many of the natural resource industries in the West have been harmed, especially family ranchers."
But it'll take some time before anything shifts for the cuckoo.
"We are launching a process that will take a year or two to complete to evaluate whether or not action needs to be taken," Norris says. "So for now, the species is on the list and protected by the [Endangered Species] Act."