21 April 2025: Grouse Lek Extravaganza with She Flew Birding Tours.
Day 3: Gunnison sage-grouse lek, Black Canyon of the Gunnison, Fruitgrowers Reservoir, to Grand Junction

The first grouse we’ll see on the Grouse Lek tour is the Gunnison sage-grouse (Centrocercus minimus) a target species for many birders because it is listed as Endangered by the IUCN and its declining population contains only 1,770 to 8,000 adult birds. Ironically the species did not “exist” until 1995 when it was split from the greater sage-grouse (Centrocercus urophasianus).

From Colorado Parks and Wildlife[1]: “In the late 1990’s Colorado wildlife researchers found that the sage-grouse in the Gunnison Basin were unique from the sage-grouse found elsewhere. Named for its home range the bird is:

• Two thirds (2/3) the size of the greater sage-grouse
• Has more distinct white barring on its tail feathers, seen from behind during the strut
• A yellow-green fleshy comb above each eye … and …
• Long filoplumes that arise from the back of the neck and are tossed up and back during the strut.
• It also has a completely separate range from the greater sage-grouse.

This map shows the current and the potential ranges both species might resettle if their numbers grew. “As of 2012 the Gunnison sage-grouse inhabited only 10% of its original range”[1].

Unfortunately the Gunnison sage-grouse is in trouble. It’s only found in seven isolated locations in Colorado and has one tiny population in Utah. Its range keeps shrinking.

In 2013 US Fish and Wildlife Service proposed listing it as Endangered but feedback from residents, ranchers, local governments, and the oil and gas industry did not want the land use constraints so for now it is listed as Threatened in the U.S.

Today our tour will see the birds from afar at a lek on the crest of a hill. We are privileged to see this endangered dance.

Learn more about the Gunnison sage-grouse in this video from High Country News.

[1] Quotes with the footnote [1] are from a 2012 video by Colorado Parks and Wildlife on YouTube. That video also shows a captive breeding program that was conducted at least a decade ago.

20 April 2025: Grouse Lek Extravaganza with She Flew Birding Tours.
Day 2: South and west to Gunnison, birding along the way.

Question of the Day: What is a lek and why do grouse do it?

“A lek is an aggregation of male animals gathered to engage in competitive displays and courtship rituals, known as lekking, to entice visiting females which are surveying prospective partners with which to mate.” — Wikipedia definition of Lek Mating

Each species performs its unique song and dance, heavily influenced by female choice. Only the females’ favorite dancers get to mate so those are the traits passed to the next generation.

Let’s take a look at the courtship ritual of the most numerous grouse in the American West, the greater sage-grouse (Centrocercus urophasianus). Notice that his “song” is something like “blub… blub blub.” The ladies hear it and come to the lek.

As males and females gather at the lek, the arrangement of individual birds within the arena changes as the strong males challenge and push away the weaker ones. The dominant males end up in the center, weaker ones on the edges (alpha-male is highest ranking, then beta-male, gamma-male, etc).

After the males’ hierarchy is established the females mate with the dominant male(s) in the center. The ladies invite mating by facing away and tenting their wings.

Q: Why a lek?

A: The ladies insist on it.