This Week in Ornithology: Domed Nests, Flaky Prairie-Chickens, and More

Babbler nests were shaped over time.

From cavities and burrows to mounds and platforms, bird nests are almost as diverse as birds themselves. But why? A team of scientists from the University of St. Andrews in Scotland used modern evolutionary statistics to confirm a nearly two-decades old hypothesis: that the dome-shaped nests of certain Old World babblers co-evolved with the birds’ preference to nest on the ground. In a paper published in The Auk: Ornithological Advances, scientists wrote that the ancestors of babblers built cup-shaped nests in trees. It’s likely that “the ground was the scariest place for them,” co-author Zach Hall says. Over time, however, some species moved to the ground to avoid competition over nest sites. The dome was incorporated to shield the nest from predators, Hall surmises.

Greater Prairie-Chickens shy away from wind turbines.

The U.S. Fish and Wildlife Service recommends that wind turbines should be placed five miles away from clusters of breeding male prairie-chickens, known as leks. As it turns out, there is good reason for this. A paper published in The Condor: Ornithological Applications analyzed 23 Greater Prairie-Chicken leks in Kansas both before and after the construction of a wind farm. It found that leks within a five-mile radius of a wind turbine were more likely to be abandoned. Other ditched leks had too few male birds or were located on agricultural fields. “The potential for trade-offs between renewable energy and wildlife populations on the landscape is one of the key questions of our day,” natural resources expert Larkin Powell, who was not involved in the study, said in a statement. 

Bird feeders are great for New Zealand's invasive birds—and less great for native species.

Backyard feeders benefit birds (and the humans who watch them), but there are also some drawbacks. They can change wild bird behavior, and help spread disease. A study published in the Proceedings of the National Academy of Sciences found another downside: Feeders may help invasive species get the upper hand. Over the span of 18 months, researchers watched birds at 23 residential gardens in Auckland, New Zealand. They observed that the sites with bread and mixed seed—the most common food items offered to birds in New Zealand—had 240 percent more House Sparrows and 360 percent more Spotted Doves than the sites without feeders. Both are invasive species. The sites with bread and seed also had fewer native Grey Warblers, though three other native species showed steady numbers.

Get some tips on how to properly feed birds here. 

New warbler discovered in China.

After nearly three decades of field research, an international team of scientists has confirmed that it discovered a new bird, called the Sichuan Bush Warbler. The bird spans five mountainous provinces in central China and appears to be fairly common. Yet because of its secretive and mostly silent nature, it is incredibly difficult to spot, the scientists wrote in a paper for Avian Research. Small and nondescript, the Sichuan Bush Warbler is nearly identical in appearance to its cousin, the Russet Bush Warbler. Its distinctive song—a low-pitched, drawn-out buzz, followed by a shorter click, repeated in series—is what sets it apart, co-author Pamela Rasmussen, an integrative biologist at Michigan State University, said in a statement. It also prefers lower elevations than the Russet Bush Warbler.