Dispersing birds

Observers: Chris McCreedy, PRBO
Email: cmccreedy@prbo.org
Remote Name:
Date: 08/10/2004
Time: 06:19 PM -0400


Hello everyone. As you know, I have been looking to track down dispersing, color-banded Willow Flycatchers that summer on Rush Creek. Today River Gates and Heidi Black, PRBO's Eastern Sierra mist-netting crew, recaptured a hatch year Willow Flycatcher. The cool thing is that we banded it on Rush Creek, around 6 kilometers away, as a nestling only three weeks ago. I had seen its sibling and its mother on Rush as recently as August 7. Over the next month or so, the remainder of Rush Creek’s adult and juvenile Willow Flycatchers will begin moving south. I am hoping that you will keep an eye out for color-banded birds for me, so that we can document more migration/dispersal movements. In addition, Chris Tonra, of Humboldt State, has color-banded several dozen Brown-headed Cowbirds, and the PRBO Eastern Sierra Riparian Songbird Project has begun color-banding Yellow Warblers and Song Sparrows. All of these birds are heading your way. Re-sighting color-banded birds is challenging and Zen. It takes patience and luck. This is particularly true for migrants, because there are no longer hormonal hazes in their brains that keep them on a territory long enough for the observer to read the color combination at her leisure. However, dispersal movements are very difficult to document, and our knowledge of what happens to the Eastern Sierra’s breeders after they leave their breeding grounds is scant. Your efforts are REALLY appreciated, and a positive re-sight of a Mono bird in the Owens would be a scintillating thing. Luckily, Yellow Warbler and Song Sparrows and Willow Flycatchers are generally found in riparian areas, and we live in the desert. There are not an infinite number of places were these birds could go. The Willow Flycatchers will always have two colors on one leg, and a metal, federal band on the other. Yellow Warblers will always have two colors on one leg, and one color above the silver federal band on the other leg. Song Sparrows and Brown-headed Cowbirds can have three bands on one leg and one on the other, or two and two – the only rule is that the silver band will always be lowest on the leg. Possible colors include: Silver, Black, White, Green, Blue, Red, Mauve, Red, and Yellow. In addition, both light blue and dark blue bands are possible on the cowbirds. A color combination is read from left leg (the bird’s left leg) to its right, and from body to toe. WR/GS =White above Red on the left, and Green above Silver on the right. And so on. Thank you so much for your effort! It is crucial to really be certain, double-checking yourself, of the color combination if you do see the bird. I will confirm a combination several times in my head before I am sure I have it correct. It helps to focus on one leg at a time, and I may say to myself: I KNOW the left leg is Green-Silver, and I think the right may be Mauve Red, etc. Also – Quresh Latif and I saw a Black-and-white Warbler on Rush on August 8 and 9! Like a zebra in a tree, but much smaller. And there were feathers.