A studio for bird study

Tag: idaho

January 30, 2016

Banded Golden-crowned Kinglet

by Bryce W. Robinson

_MG_4949.jpg

This past fall I helped the Intermountain Bird Observatory band birds on a number of occasions at a site along the Boise River. I’ve returned to the location on occasion throughout the winter to bird, and every time I find a small mixed flock with banded individuals throughout.

The other day I made attempts to photograph banded birds to capture band numbers and identify individuals. Easier said than done when the flocks are busy foraging. I came away with some good photos, but nothing that put together a full sequence or even the last few digits.

It can be said, however, that these birds are most likely the same birds that were banded here in October. The other most plausible explanation is that some were banded at IBO’s other site, only a few miles away on the top of Boise Peak. I’m unfamiliar with the literature on winter movements of the Golden-crowned Kinglet, so I don’t have an idea if holding a small range throughout winter is common for this species. Still, the birds I photograph seem to be staying put which surprises me in some way. Perhaps the inclination of the flock to stay within a small range speaks to the quality and perhaps importance of the habitat provided by this relatively wild portion of Boise’s section of the river.

Time to read, and think some more.

1 Comment
January 21, 2016

Black Rosy-Finch Use Cliff Swallow Nests to Roost

by Bryce W. Robinson

 

East of Boise, Idaho, on a cliffside along the Boise River is a conglomerate cliffside of volcanic rock. On this cliffside is a group Cliff Swallow (Petrochelidon pyrrhonota) nests. The Cliff Swallow is migratory, so during the winter months the Cliff Swallow does not occupy these nests.

In winter, the mud cavity nest sites are utilized by other bird species as roost sites. Interesting, to me, is that wintering Rosy-Finch species use these nest sites as well. I finally succeeded in capturing a video clip of a Black Rosy-Finch (Leucosticte atrata) entering a mud cavity to roost for the evening.

The composition of the flocks at this particular site are also of interest. Take a look at the eBird checklist of the time I spent filming this small flock. Most were Black Rosy-Finch, the next most numerous were “Hepburn’s” which are a coastal breeding subspecies of Gray-crowned Rosy-Finch, and there was only one “tephrocotis” Gray-crowned Rosy-Finch, the interior subspecies.

http://ebird.org/ebird/view/checklist?subID=S27027048

The regularity of this Cliff Swallow – Rosy-Finch relationship is of interest to me. I have read accounts of the behavior in California and Washington, but these accounts are few. I do not know of other areas that these birds currently use Cliff Swallow nests, but I will be searching for them and would appreciate any information from other’s observations.

Wintering ecology, what a fascinating faction of bird study.

 

 

Leave a comment
Video | January 5, 2016

American x Eurasian Wigeon Hybrid

by Bryce W. Robinson

 

The phenotypic expression that results from hybridization is fascinating, especially in colorful birds such as the male ducks. One duck hybridization I enjoy is the American x Eurasian Wigeon. The subtle combination between the traits of the two species is pleasing to the eye, but also presents a fun and satisfying ID challenge.

I found a drake American x Eurasian Wigeon the other day in a large group of American Wigeon feeding on a grass field at a large sports park in Boise, ID. The winter group that frequents this field every year generally holds a drake Eurasian Wigeon. This year no Eurasian, but a hybrid.

_MG_4612

Note the retention of the American Wigeon head pattern. The Eurasian has a beautiful red-orange head with a golden fore-crown. The neck and auriculars do not differ in color than the superciliary and hind-neck as in the American. This hybrid holds the American pattern, but with strong Eurasian coloring throughout the head. The other most obvious quality on this bird is the gray flanks unlike the American Wigeon which have rufous flanks. Thus, the combination of American head pattern with reddish hints and the gray flanks are enough to confidently call this bird an American x Eurasian Hybrid.

_MG_4621

Eurasian Wigeon sure show up regularly each winter in N. America. I’d love to know if the regularity of Eurasian in N. America mirrors the regularity of American in Asia. It’s fun to wonder, but with the growing popularity of eBird, answering these types of questions are beginning to seem more and more possible.

Leave a comment
April 25, 2015

Short-eared Owl Wing-clap Flight Display

by Bryce W. Robinson

Breeding flight displays in birds are a blend of the bizarre and the fantastic, a show of a birds talent and specialty in communicating it’s unique ability to portray fitness. The Short-eared Owl is no exception, as a low consistent hoot softly settles on the sky, while the bird flies with deep, moth-like wingbeats. Then, as if in suspense, the bird begins to clap its primaries in rapid motion, falling from the sky. After multiple claps and an appreciable loss of altitude the bird spreads its wings and continues its deep wing beats as before. The wing-clap is displayed in seeming desperation, as if the bird is throwing all caution to the wind to produce the most excellent round of claps for onlooking (or listening) females, and intruding males.

I rarely post videos back to back, but I’m making an exception this time because in the same evening I was privy to both Long-billed Curlew and Short-eared Owl flight displays. Both were “on my list” of behaviors to capture on video, and my excitement for capturing both in one evening is too difficult to quell. So I share…

This bird flew tirelessly. For near an hour, the owl flew in the sky performing wing clap after wing clap, all the while letting out a low consistent hooting barely audible to my ears. What a scene, and such a scene that I encourage anyone in the area of breeding Short-eared Owls to search out the chance to observe this behavior in real time. It’s bizarre, but it is at the top of the list for must see in behavior birding, and for good reason.

In the future I’ll be refining my camera skills and upgrading my lens, all in hopes of getting a more clear documentation of this behavior. For better video quality, click through the video link and watch on Vimeo in HD.

Leave a comment