IBO keeps a watchful eye on curlew population
A long-billed curlew was poached in the Morley Nelson Snake River Birds of Prey National Conservation Area southwest of Boise on June 1. The death means seven of 16 birds fitted with transmitters by researchers have been killed by suspected poachers since 2013.
Of the 50 birds fitted with transmitters in other parts of Idaho, Montana, and Wyoming, none have been poached, according to researchers at Boise State University.
The poaching prompted scientists and wildlife officials to think about how to better inform and educate people about the birds and their vulnerabilities, especially the critical curlew habitat so close to Southern Idaho population centers and recreation areas.
Curlews are migratory birds, raising their young in the Mountain West from March to June and wintering along the coasts of California and Mexico. But populations that nest in Southwest Idaho are in steep decline, with as much as a 90 percent decrease in some areas since the 1970s, and Boise State researchers are trying to understand why.
One of their findings: Humans are one of the curlews’ most deadly predators.
“The proportions are alarming,” said Jay Carlisle, associate research professor at BSU and research director of the Intermountain Bird Observatory.
Carlisle and his group focus their research on understanding the reproductive success of the curlews in different habitats as well as studying migratory patterns using lightweight satellite transmitters. In the Treasure Valley, curlews nest in three different areas: The Birds of Prey conservation area; Twenty Mile South Farm, within the Birds of Prey area; and the Long-Billed Curlew Habitat Area of Critical Environment Concern northeast of Star, where the greatest losses have been seen. Curlews are a large, charismatic species of bird, making it easier to study the factors in the broad decline of grasslands birds.
The curlew poached June 1 was found by two of Carlisle’s researchers, Stephanie Coates and Joni Clapsadle. The female bird had been shot through the wing and body, indicating that she was sitting on the ground when killed, close to her nest. "This female was simply shot because she was there," a press release from the Intermountain Bird Observatory said.
Another case of poaching in the same area was confirmed by Idaho Fish and Game on June 11, a male curlew that had been fitted with a transmitter by the Boise State group. Two more dead curlews were found on June 11 by a National Guard crew at a watering hole near Pleasant Valley Road south of the Boise Airport. Poaching has yet to be confirmed but “it’s kind of suspicious when you find two carcasses with no sign of predation”, says Carlisle.
At research sites outside the Treasure Valley where curlews raise their young, no poaching has been reported.
So, what makes Southwest Idaho different?
Part of the answer is the higher population density of humans. In these desert areas, target shooting is common. Curlews, when incubating their eggs, are inconspicuous. They blend in to the environment well and don’t give alarm calls unless people approach very closely. This makes them vulnerable to stray fire.
Once curlew eggs hatch, the birds drastically shift behavior and aggressively protect their young. When approached, the birds frequently dive bomb in an attempt to scare off threats and protect their young. Carlisle said people have told him that when this happens, they will sometimes shoot them.
“Just move on a few hundred yards,” he said, “We tell people, ‘Wouldn’t you do the same?’”
But Carlisle said the recent poaching cases are something more, with birds appearing to have been killed for no other reason than target practice — or worse, for no reason at all. “It’s more than people responding to curlews attacking them, defending their young.”
Carlisle points out that he and his group have not built a complete model that includes all potential causes of curlew population decline, such as being killed by predators or habitat change. But shooting deaths can be fairly easily separated from these other causes. “This is the only aspect of mortality that alarms me.”
So, what can be done?
Carlisle said that public outreach is the key. The bird observatory offers a program called "Curlews in the Classroom", which reaches thousands of students in the Treasure Valley each winter. It offers field trips for teachers and the public called "Curlews Out of the Classroom," as well as signs and outreach events in prominent outdoor locations, together with the BLM, Idaho Army National Guard, Idaho Fish and Game and others.
Officials have begun including curlew information in local hunter's education classes. The researchers also rely on social media coverage: "Both of exciting updates," he says, " and of the less fun aspects like 'yet another shot curlew'".
The observatory is also working with law enforcement. The curlew is neither an endangered nor threatened species, but is protected under the Migratory Bird Treaty Act. Killing a curlew is a federal crime — a misdemeanor punishable by up to a $15,000 fine and six months in jail.
Given the size of the bird's habitat and the limited number of officers, however, law enforcement alone cannot address the problem.
Carlisle stresses the importance of informing land managers and the community at large. The alternative is dire. “In a decade, we may have a place named the Long-Billed Curlew Habitat Area of Critical Environmental Concern that doesn’t have curlews anymore," he said. "How sad would that be?”
ABOUT THE LONG-BILLED CURLEW
Scientific name: Numenius americanus
Range: The bird often nests in the Great Basin and the Great Plains, and winters from the Caribbean through Mexico and west to California.
Size: Adults weigh about 2.2 pounds and have a wingspan of 24 to 35 inches, making it the largest shorebird in North America.
Food: Insects, crabs and other invertebrates.
Nesting: It breeds in grasslands, where the birds go through a sophisticated dance before building a nest in a hollow surrounded by short grass. The male and female alternate sitting on the nest. The chicks quickly leave the nest after hatching.