Tuesday, December 8, 2009

Black Rosy-Finch

Black Rosy-Finches are uncommon birds of the high mountains in the central US, which nest above tree line; often nesting higher than all other birds on a particular mountain.

This beautiful shot contributed by Bill Maynard,
editor of the American Bird Conservancy's publication "Winging It"
Look for samples of the publication on that last link!

These birds favor alpine tundra near rocky slops and cliff faces but winter at lower elevations. They are among the least studied of North American birds because of the inaccessibility of their alpine habitat generally, and specifically that they nest on high cliffs. Reflecting this, very, very few nests have been reached (only 3-4 as of 2002!) and only a few studies have focused on the species.

The Black Rosy-Finch is most likely to be confused with other rosy-finches but it lacks the brown look to its plumage. Its color is so dark it appears to be black on the back, breast, neck and face. Its forehead is black and a gray band wraps around the back of the head, behind the dark forehead. As with other Rosies, its bill is yellow in winter and dark during breeding season.

Juveniles are similar to female, but lighter, usually grayer brown, lacking silver-gray crown, dark forehead, and pink on feather margins.

During the winter, this finch is often found in mixed flocks with other Rosies throughout Colorado’s western mountains and east to eastern foot of Rockies. It is rare on plains east of mountains in northern part of state and less common in Colorado than other rosy-finches, averaging about 5% of flocks, except perhaps higher in extreme west (Grand Junction.) Black Rosies also winter irregularly across the northern tier of counties in New Mexico (except Union Co. in northeast corner) and south as far as Albuquerque; famous in the Sandia Mountains.

This shot shows how dark a Black back is
compared to a Brown's.
I love the beautiful patterns...

This Rosy hybridizes with other Rosy-Finches, though like all Rosies it is little studied. The extent of hybridization is unknown and many birds may be unidentifiable.

Wintering flocks of Black Rosy-Finches roost in large communal roosts in abandoned buildings, caves, mine shafts, on rafters of barns, and in clusters of old Cliff Swallow nests. Old mine-shafts may be especially valuable to this bird. Unlike other Rosies, these have never been found to nest in buildings.

This Rosy breeds in alpine areas, usually near rock piles and cliffs at elevations of 10,000 – 13,000 feet, wherever outcroppings and rock slides provide nest sites with protection from falling rocks and hail. Almost always nests look out over the tundra and valleys where they feed.

Conservation: While there are no apparent population trends; Black Rosy-finches might be declining. Because these, like other Rosy-Finches favor extremely remote breeding habitat, it is unlikely human population will adversely affect it. These birds seem almost tame and will tolerate people within three feet. Adults are tolerant of researcher-visits to their nests, so likely would not be disturbed by human recreation like climbing and skiing; however Common Ravens drawn by human garbage could cause negative impact through increased nest predation. Domestic grazing animals could reduce food supplies and attract Cow-birds that also predate; climate change will likely cause habitat loss and fragmentation and the loss of some populations. Increase in radioactive fallout could lead to significant accumulation in body tissues because of species’ habit of foraging on high-elevation snowfields that frequently concentrate fission-products to high levels. Like mercury levels in the deep-sea tuna, perhaps Rosies are the 'canaries in the mine-shaft' of our world. I only wish we'd take heed!

While feeding these birds will surely help them, it will also make them vulnerable to cats and window-strikes. Please keep your cats inside and your feeders near windows where birds can’t get up the speed to hit hard. I have found bird-netting placed outside over picture windows to be quite effective and causes little to no restriction of view and photography.

The Sibley Field Guide to Birds of Western North America – David Allen Sibley
Smithsonian Field Guide to the Birds of North America – Ted Floyd
Western Birds – Roger Tory Peterson
Birds of North America-Online from Cornell Lab of Ornithology
WhatBird.com - Field Guide to Birds of North America – also from Cornell Lab of Ornithology
USGS.gov - Science for a Changing World
Photos are mine... Except the first one that Bill Maynard kindly allowed me to use!

This is the second of a four-part series on Rosy-Finches


Camera Trap Codger said...

Did I miss something, or did you get a new camera?? Nice post, too!

Beverly said...

Nooooooooo, you are VERY kind though, Chris. Actually, that is one of the few photos I got without shooting through old glass!

The rosies are so tame I was able to open the back door, sit on a bucket just inside, and take pictures of the birds not three feet away! (Froze my butt, though)

I have a nearly ten-year old Power-Shot G3; a bulky ‘little’ Cannon with 4.0 mega pixles! Hey, it was awesome back then that I even found a digital camera that took other lenses; and got the whopping 2x lens that I could afford. [sigh]

Someday I’ll win the lottery…just as soon as I start buying them, I suppose. LOL

Thanks for dropping by…and please give your pup a happy birthday pat for me! I love that you post about him!