Two Red Deer stags stand in the early morning mist in Richmond Park on October 15, 2011 in London, England. Autumn sees the start of the “Rutting” season where the large Red Deer stags can be heard roaring and barking in an attempt to attract females known as bucks. The larger males can also be seen clashing antlers with rival males. (Photo by Dan Kitwood/Getty Images)

Buyan, a male Siberian brown bear, cools down under a stream of water sprayed by an employee in an enclosure on a hot summer day, at the Royev Ruchey zoo in Krasnoyarsk, Russia on June 14, 2019. (Photo by Ilya Naymushin/Reuters)

A photographer in Somerset, South West England captured the mating rituals of toads as several males attempt to mate with one female all at once. (Photo by John Waters/NPL)

An Oriental Garden Lizard sits on a tree in Gauhati, India, Tuesday, April 16, 2019. During the breeding season, the male lizard's head and throat turn a bright color. (Photo by Anupam Nath/AP Photo)

Buyan, a male Siberian brown bear, cools down under a stream of water sprayed by an employee in an enclosure on a hot summer day, at the Royev Ruchey zoo in Krasnoyarsk, Russia on June 14, 2019. (Photo by Ilya Naymushin/Reuters)

Almost two years old male baby orang-utan Dalai looks on in the zoo in Dresden, Germany, 30 March 2017. Dalai was born to mother Daisy in June 2016. (Photo by Filip Singer/EPA)

A professional training in explosive disposal is held in Nanning, Guangxi, China on 18th February, 2021. (Photo by Top Photo Corporation/Rex Features/Shutterstock)

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.