Secret Sex Lives of High-Nesting Finches Uncovered In Rockies

James Owen
for National Geographic News

August 24, 2004

Mountain accidents are an occupational hazard for University of Wyoming researchers on the trail of the rosy-finch, North America's highest breeding birds.

The risks the researchers face were highlighted last month when one of David McDonald's graduate students fell during a climb. She was trying to reach a rosy-finch nest perched at more than 10,000 feet (3,050 meters) in the Snowy Range of the Rocky Mountains.

Printer Friendly

Email to a Friend

What's This?

Paramedics had to be called to provide a medevac for the student, who has asked not to be identified for this story. "It's a testament to her youth and resilience that she seems to be mending well," said McDonald, a zoology professor at the University of Wyoming, Laramie. "She feels that, for the moment, lab genetic analyses are as extreme as she wants to be."

The nest proved to be the first nest of a brown-capped rosy-finch recorded in Wyoming.

It marks the latest breakthrough for McDonald and his team in their efforts to map the nesting sites and understand the breeding behavior of these poorly studied birds.

Currently, there are thought to be three species of rosy-finch in North America (though McDonald says even this isn't known for certain). These are the brown-capped, found almost exclusively in Colorado; the black, which ranges from New Mexico to Montana; and the gray-crowned, the most widespread variety, which breeds as far north as Alaska.

All three have characteristic pale rosy markings on their undersides and wings. The problem for researchers is that rosy-finches are the highest breeding birds in North America. "They are also the highest breeding vertebrate in the lower 48 [U.S. states]," McDonald said. "I suspect they rarely nest below 11,000 feet [3,350 meters] in Colorado and 10,000 feet [3,050 meters] in Wyoming."

Tough Birds

Describing them as "tough, resilient birds," McDonald says rosy-finches breed at such unforgiving altitudes to escape predators and competitors.

"If you're tough enough, the rocky crags and alpine meadows provide abundant seed and insect resources, as well as cracks that hugely decrease vulnerability to predation. The steep cliffs eliminate accessibility for mammals," McDonald said.

In 2002 another University of Wyoming graduate student, Maureen Ryan, discovered only the fourth nest of a black rosy-finch ever recorded. This was in Utah's Uinta Mountains.

The nest was found while field-testing geographic information systems (GIS) equipment as a method to locate these birds. The nest contained a clutch of five eggs, opening up a new avenue of research.

Continued on Next Page >>