Migrating starlings fly in formation near the southern Israeli town of Rahat February 2, 2015. The phenomenon, known as murmuration, is most common during the winter months. (Photo by Nir Elias/Reuters)

Swans swim over a lake, with the air temperature at about minus 35 degrees Celsius (minus 31 degrees Fahrenheit) as steam ascends above the water during sunset near the village of Urozhainy, Sovetsky district of Altai region, January 26, 2015. About 600 swans annually migrate to the lake, which is heated by warm springs, where they spend their winter being fed by yagers, which helps them to survive the severe cold. (Photo by Andrei Kasprishin/Reuters)

A bird is cleaned at the International Bird Rescue in Fairfield, California January 20, 2015. A gooey, unknown material discovered on the eastern shores of San Francisco Bay is clinging to the feathers of birds, and more than 100 birds, mostly species of oceangoing, diving ducks, have died after their feathers were fouled by the viscous substance now undergoing testing at state labs in Sacramento. (Photo by Robert Galbraith/Reuters)

Golden-crowned Kinglets boldly bear their flashy lemon-yellow crest and a black eyebrow stripe. Taking a good look at them might be rather challenging, since they spend most of their time in the dense fir foliage or spruce. However, if you’re patient enough to find them, listen for their shrill, thin song. Though these “little Kings” are only a tad bit larger than a hummingbird, they can survive easily extreme cold by huddling close together. They breed in montane west and the far north and only visit North America during winter.

“I’d come to the Altai Mountains on an Adventure Sherpas tour. Our group of 12 was made up mostly of Minnesotans who’d left warm weather and falling leaves for frosty Mongolia. We’d come to sleep in cozy ger tents, the traditional yurt abode of the Mongolian steppe; sip mare’s milk tea; climb mountain glaciers; ride horses to an ancient battle site, and attend the annual Eagle Hunting Festival in Ölgiy...”. – Kathryn Kysar via The Star Tribune. Here: hunter Berek and his eagle outside his home. (Photo by Brad Ruoho/The Star Tribune)

Vanessa Silva, 38, feeds macaws that fly to her apartment window every day looking for food, in Caracas, Venezuela, on November 24, 2014. A group of gold-and-royal blue birds poked their heads through Silva’s window, as if saying “I’m here, is anyone home?” “I’d seen them flying when I was down on the street, and I thought ‘Oh how pretty,’” the 38-year-old said, a macaw eating out of her hand. (Photo by Ariana Cubillos/AP Photo)

The Greater Sage-Grouse is certainly a formidable-looking bird. Being the largest grouse in North America and having tail feathers, which look like giant spikes, make for a ferocious sight. These birds are well known for their complicated courtship rituals, in which the males perform a special “strutting display” to attract the females. Another distinct feature of the Greater Sage-Grouse is two large yellow throat sacs (gular sacs), which are inflated by the males during the courtship display. Unlike pelicans, whose gular sacs are used to store fish while hunting, the throat sacks of the Greater Sage-Grouse are merely for display.

A chicken has invaded the pitch at Blackburn Rovers during a Championship football match against Burnley.