Critics said the western population of yellow-billed cuckoos should not have been declared a threatened species because it is not distinct from thriving populations of the bird in the eastern U.S. (Photo by Dan Pancamo/Creative Commons)

WASHINGTON – Federal officials said they will re-evaluate the threatened species status of the western yellow-billed cuckoo, after petitions from Arizona miners, ranchers and other groups argued that the species is no different from thriving eastern populations of the bird.

The notice Wednesday by the U.S. Fish and Wildlife Service comes in response to a May 2017 letter from the groups who argued that the 2014 decision to declare the bird threatened was a mistake. They also said that threats to the bird’s survival “do not now and never have risen to the level that protection under the ESA (Endangered Species Act) is warranted.”

But environmental groups said they will fight any move to remove the cuckoo, which they said “plays a unique role in an ecosystem, being up there in the canopy and ambushing caterpillars and other small invertebrates.”

“These tenacious, beautiful birds play an essential role in balancing nature in areas, but they also build a metric for how well we conserve beautiful areas that we all value,” said Michael Robinson, a conservation advocate with the Tucson-based Center for Biological Diversity.

The Fish and Wildlife Service said that while the yellow-billed cuckoo is found throughout the eastern and central U.S., the western subspecies of the bird has disappeared over much of the West. They prefer dense wooded areas with water nearby, but much of its habitat in the West has been lost to farming and housing, the government said.

It also said that the birds, as long-distance, nocturnal fliers, are “vulnerable to collisions with tall buildings, cell towers, radio antennas, wind turbines and other structures.”

The National Park Service said the western yellow-billed cuckoo is nearly vanished in the Pacific Northwest, with most of the remaining birds found in “isolated patches of riparian habitat along rivers in Arizona, California, and New Mexico.” It is found in limited numbers in every county in Arizona, according to Fish and Wildlife.

The Center for Biological Diversity said the cuckoo’s western population was “first identified as needing federal protection in 1986,” and the center first petitioned to have it listed under the Endangered Species Act in 1998.

But opponents – including the Arizona Mining Association and Arizona Cattlemen’s Association, among others – are challenging the listing of the western birds as a separate subspecies. Their petition said that based on “both new data and new interpretations of previously available information,” they believe the western populations of the bird are no different from the eastern segments.

The government said Wednesday that there was enough new evidence for it to begin a review.

“The crux of the petition is questioning the differentiation between the eastern and the western (yellow-billed cuckoo),” said Jennifer Norris, the field supervisor at the Sacramento office of Fish and Wildlife. “The petition was to delist it. If we got through this long process and agree with that proposal, it would be taken off the list.”

Over the next year, Fish and Wildlife officials will collaborate with state agencies and other authorities to complete a comprehensive species status assessment, looking at the fundamentals about the species and its status and threats.

But agency officials stressed that this is just the first step in what could be a long process.

“The western (population) of the yellow-billed cuckoo will remain listed as threatened pending what is realistically a two-year scientific process,” said Jeff Humphrey, a spokesman for Fish and Wildlife.