Some call the yellow-billed cuckoo the “rain crow,” based on a belief that its singing announces a coming storm. That’s just a myth, says Peter Tallman, an “opportunistic birder” and the only plumber for 100 miles in the southern New Mexico town where he lives. Work takes him through lots of backyards, where he pauses to listen or watch for the cuckoo’s characteristic swoop and spotted tail among the branches.
What is true, Tallman notes after six decades of watching birds, two of them in the Southwest, is that yellow-billed cuckoos are almost always found in the forested areas along waterways. He knows that from walking through those bosques or stopping for lunch at a riverbank, places with a density reminiscent of their former numbers.
“They’re what they should be,” he says. “Every 200 or 300 yards, you’re in the next cuckoo’s territory.”
Their call — whatever it heralds — of “ku-ku-ku-kddowl-kddowl” makes that clear. Tallman says he can sit on his porch with binoculars aimed into the trees lining the irrigation ditch 50 feet away and watch for them. The cuckoos follow that ditch from the river three miles away like humans would follow a footpath.
The American Southwest provides a last stronghold for the yellow-billed cuckoo, which was officially listed under the Endangered Species Act as threatened in 2014. This February, the US Fish and Wildlife Service published a list of proposed protected areas that trace the curls and curves of rivers and streams in Arizona, California, Colorado, Idaho, Texas, and Utah. Some say these new protections for the yellow-billed cuckoo’s future could extend to some of the West’s most threatened rivers.
“This is a bird that depends on healthy rivers, and what may be turning out here is that the rivers also depend on saving this bird,” says Michael Robinson, a conservation advocate with the Center for Biological Diversity, which has long sought protections for the western population of yellow-billed cuckoo.
At 12-inches long, yellow-billed cuckoos are just slightly bigger than robins but with a slimmer profile. Their guttural calls are easy to hear, though cuckoos are known to be secretive and tough to spot. A birder hoping to detect one among the trees should watch for the white flash of their underbellies or the strokes of cinnamon wings, and a row of three white spots down their tails. They hunt cicadas, katydids, even the occasional frog or lizard, and are one of few species that will eat hairy caterpillars, like tent caterpillars. Yellow-billed cuckoos migrate to South America for winter and spend summers in North America. Because their young grow fast and rely on abundant food to do so, they nest in contiguous, multilayered wooded areas — often cottonwood trees and willows — along rivers and streams, where cooler, humid conditions support plenty of insects.
Their numbers have plummeted as diversions, dams, and development have reshaped those waterways. Human encroachment has cut into riparian forests; regulated river flows have ended the seasonal flooding cottonwoods rely on to germinate; and nonnative plants, like tamarisk and Russian olive, have overtaken stream banks. When conservationists began the effort to protect the western population of yellow-billed cuckoos, their numbers in some states were startlingly small. Surveys found no more than 33 pairs in California and less than 200 in Arizona. The Center for Biological Diversity estimates that at most 495 pairs live in the United States.
“Yellow-billed cuckoos deserve protection in their own right, and I also think they’re an indicator for what could go wrong in our rivers,” says Jen Pelz, Rio Grande waterkeeper and wild rivers program director for WildEarth Guardians. “When a species starts to decline, it’s pretty clear the health of the river is failing, and, taken to its logical conclusion, if our river health fails all over the West, that’s going to have implications for people.”
The list of proposed protected areas includes habitat along two of the West’s most iconic, and most overdrawn, rivers: the Colorado and Rio Grande. Both are so over-tapped — more water is promised to downstream users than actually flows in the river — that their riverbeds are dry for hundreds of miles. The list also names habitat along the Salt and San Pedro in Arizona, Sacramento and South Fork Kern in California, Gunnison in Colorado, Snake and Henry’s Fork in Idaho, and Gila and San Francisco in New Mexico, covering more than 1,200 miles. Habitat was selected based on where yellow-billed cuckoos are found, and what creates a sizable and diverse range for the species.
“We want to identify areas with the best bet for recovery,” says Jennifer Norris, field supervisor for the US Fish and Wildlife Service’s Sacramento office.
The proposal revises an effort from five years ago that was never finished, Norris says, because of short staffing. In this round, which a court settlement mandates be finalized next year, the proposed habitat shrank by 30 percent. That’s a product of more robust assessments, Norris says. WildEarth Guardians have asked the agency to explain each reduction.
Almost every river and stream on the 2020 list is forecast to see threats from surface water diversions, groundwater extraction, overgrazing, and unauthorized off-highway vehicles. When the critical habitat is finalized, constructing new dams, diversions, or other development on federal land in those areas would require planning with the Fish and Wildlife Service to avoid impacting yellow-billed cuckoos.
Dam operators, irrigation ditch associations, mining companies, an oil and gas association, and even a powerline company submitted objections to the critical habitat proposal during a public comment period that finished April 27. Generally, they asked the Service to designate critical habitat protections outside where they work. Most expressed worry that how they do business will change.
Along the Rio Grande in New Mexico, Elephant Butte Irrigation District manager Gary Esslinger points out that the Elephant Butte Reservoir exists in part to fulfill a treaty obligation between the United States and Mexico and to supply farmers in New Mexico, Texas, and Mexico in hot summer months.
“When we call for the water, it’s for the crops, and it has been that way forever,” he says. “To throw a curveball at us and say, No, you need to release for this bird, we’re going, No, that’s impossible.”
Esslinger also points out that the district worked with a local Audubon chapter to water replanted cottonwoods and willows on 80 acres, with another 400 in mind. That work has helped keep the area from becoming official critical habitat for southwestern willow flycatchers, another endangered riparian bird.
According to Norris, critical habitat designation is better suited to preserving what’s left for the future than reversing existing issues. The agency selected places where cuckoo have survived; the goal now is to hold that line. If change comes, Norris and others say, it’s because the designation calls attention to species in need and where best to help them.
“It’s not going to turn them back into wild rivers,” Norris says. “The ESA isn’t that powerful.”
Habitat restoration for the yellow-billed cuckoo may require reframing our perceptions of nature and rewriting water law, Pelz says, which doesn’t allocate water to the river itself, only to people who want to draw from it. There’s concern as well that climate change will widen gaps for already overdrawn western rivers.
“The only way we’re going to get to a point where these threatened or endangered species can actually thrive again is to undo some of the damage that had already been done,” Pelz says. “A friend called it ‘ecological amnesia.’ … In the Rio Grande, there’s 250 miles that never has any water in it, and people just assume that’s how it always was, and that’s not how the river always was.”
Maybe dams won’t be torn down, Robinson says, but in years ahead, other projects may not move forward, particularly if they would decrease water levels or prevent flooding in riparian zones.
“You can’t designate over 1,200 miles of habitat and not do anything to protect it,” he says. “The Endangered Species Act and the cuckoo’s plight will require real limitations on what can be done to rivers, and in some cases, will require rivers that have been destroyed to be repaired.”
Meanwhile, Tallman says that even with some damage around the edges, a mostly intact bosque means that cuckoos seem to do all right. Those strips of green in a desert state are both beautiful and useful, he says, and they could use some help trying to recover: “I support whatever protections we can get.”