The Gunnison grouse or Gunnison sage grouse was once considered a subspecies of the greater sage grouse. These birds are native to the sage brush range of the West. They require forbs and grasses to sustain themselves and dense stands sage for cover and winter browse. They also require access to creeks and small streams, where they can drink and brouse on more lush vegetation.
The greater sage grouse lives in similar habitat, but the Gunnison was southwestern Colorado, southeastern Utah, northeastern Arizona, and northwestern New Mexico. Today, it is found in two isolated populations in Colorado and Utah. The greater sage grouse has a much more extensive range is frequently shot as a game bird.
Until the year 2000, the Gunnison sage grouse was regarded as the endemic subspecies of the Greater sage grouse. It was only when it was discovered that the Gunnison was genetically distinct that the American Ornithological Union changed its species status. These studies found that the two rarely did so.
The mating display of the Gunnison is different from the Greater sage grouse. Both of then go through elaborate lek displays that involve popping their airsacks on their breasts. The cycle of popping lasts about three seconds in both species. However, the Gunnison pops nine times in that three second cycle, while the Greate sage grouse pops his air sacks only twice during its cycle. The Gunnison produces fewer cycles per minute, and the noise produced through the air sacs is quite different for both species.
Gunnison hens grouse will actually avoid the mating sounds of a male Greater sage grouse. So it is pretty clear that they are separate species. After all, we do know that behavior is one way that species remain “pure.” Some animals could easily interbreed, but their mating behavior simply prevents it.
The Audubon Society has listed the Gunnison as one of the ten most endangered bird species in North America. However, the Fish and Wildlife Service refused to put them on the Endangered Species List in 2005.
The main reason why it became endangered is really quite simple. The ranchers of that region have allowed the cattle to overgraze the range lands, destroying grouse habitat and food sources. Furthermore, in the southwestern part of its range, there are known natural gas and oil reserves that have not been fully explored. Considering who was in power in 2005, we know than anything that would have encumbered the oil and gas and ranching interests simply would not have been considered. Cattle erode the soil, making great washes on the land, and they eat lots of forage, denuding the land of adequate cover and sustenance for the Gunnison grouse. Really suitable habitat for the Gunnison is becoming more and more fragmented.
So the Gunnison is one of the newest recognized species in the US, and it is also one of the most endangered. However, we need our government to recognize it as endangered. Heck, we need our government to recognize it as a species. Refusing to recognize it as a distinct species is one of the tactics used to deny it Endangered Species status.
A very informative website that explains the biology of the Gunnison grouse can be found here. Another website with lots of information on this species and the fight to put it on the Endangered Species List can be found here.
Finally, I would be remiss here if I didn’t show you a video of the sage grouse species displaying in their leks. It is quite bizarre.
Here’s the Gunnison’s:
And the Greater sage grouse:
