Wednesday, January 30, 2013

in decline: ruffed grouse






Ruffed grouse are darn handsome birds. But, coming in at number 20 on Audubon's list of 20 Common Species in Decline, they are a species on the ebb not the flow. To make the list, a species has to have lost 50 percent of their overall population since 1967. 

A local population of ruffed grouse is cyclical to begin with: they go through highs and lows, roughly every ten years. In some places, every 20 years there's a super high. It seems to be tied to predator/prey availability cycles.  If a great horned owl is hungry and it cannot find anything else, cannot locate a hare or rabbit, boom there's an unassuming ruffed grouse like a roister chicken, warm and ready to eat at Kroger's.

Consequently, ruffed grouse weren't very good at staying alive. They live longer than New Year's Resolutions, but not by much.  

Born on the ground, they are vulnerable from the get go. Few survive past age three. A study carried out in Minnesota revealed that if you start with 1,000 ruffed grouse eggs in the spring, you will only have roughly 250 young grouse alive in the fall. By the following spring only 120, only about 50 one year later and only 20 the next. Less than two dozen out of 1,000 in just three years. It's hard to sustain a population with that kind parsimony. 

If you factor in habitat loss and other human-related causes, it could spell doom with a troubling disco beat.

Ergo: (cue the Bee Gees) ruffed grouse just aren't very good at ah, ah, ah, ah, stayin' alive, stayin' alive. 

2 comments:

Dorothy said...

We chanced upon some on these in the Smokies, and I got so excited I missed getting his picture in full strut.

Marie said...

This was so interesting...and sad. I hope they don't continue to decline!

Check out a blog of a teacher who lives not far from me...he's an avid birder and is posting a lot of great birds-- Las Aventuras. You can find him on my sidebar.