20 Apr 2015 — PNW Migration Update

Over the weekend there have been a few reports of MacGillivray’s, Wilson’s, Nashville and Hermit Warbler, somewhere in Oregon a Western Kingbird, the first report of a Cassin’s Vireo, and a few “Western” Flycatchers.  Shorebirds are beginning to build in numbers as they move through.

Out on Sauvie Island (where i spent my weekend) Sandhill Crane numbers are way down as are most waterfowl numbers.  I haven’t seen a Canvasback or Ruddy Duck for a few weeks now and Scaup and Bufflehead are hard to come by.  Double-crested Cormorants are gone, and a few A. White Pelicans are moving through — probably on their way to the recently established breeding colony on the lower Columbia.

Last night’s radar (KRTX) was lit up solid green.  The stable, calm weather as a new ridge establishes is providing a nice set of flight conditions and the birds are taking advantage. I threw in a loop of the Medford (KMAX) radar because it’s rare to see such density from this station.

Update: Warbling Vireo, Yellow Warbler, and Western Tanager have made it to the Willamette Valley.

13 Apr 2015 — PNW Migration Update

Excellent conditions – clear skies and a bit of a tail wind – lots of birds moving up the Pacific Flyway.

Bank Swallows and Yellow-breasted Chats have made it into the San Diego Area.  Tanagers are up into the Central Valley.  And Hermit Warblers are moving through the Coast Range here in Oregon.

Mike Patterson, who writes the North Coast Diaries blog, has a great piece on phenolongical variation across Oregon’s differing ecoregions.  It’s here  — highly recommended.

It was another night where the large scale impact of weather on migration is clearly on display.  So i threw in a National Radar Composite and a map of the winds at 850 mb heights (roughly 1500 meters).

For commentary on the migration through New England check out Tom Auer’s Blog.  Also, today he has some information on a new radar product coming out of NOAA.  It’s a product they are calling “Bioscatter“.  My guess it is the same algorithm, or a clone, that derives the Hydrometeor Classification images found at the College of DuPage’s weather site, and that i highlight here at times when separating birds from rain.  I have added it to the sidebar under the Weather section.  You’ll have to figure out how to access it by navigating their product menu.