04 May 2015 — PNW Migration Update

Moderate to heavy migration took place all weekend. New arrivals were everywhere out in the field.  I still haven’t seen any reports for Western Wood Pewee or Willow Flycatcher.  Good numbers of Swainson’s Thrush were out and tonight, in a clear, full moon sky, i heard about a half a dozen nocturnal flight calls in the two minutes i spent listening.

The Atlantic Flyway finally got some love last night.  For a full report head over to Tom’s recap.

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20 April 2015 — PNW Migration Update

Yesterday in the narrative we had twelve migrants yet to be reported in the Northern Willamette Valley.  To day we are left with eight.  Yesterday there were reports of Yellow-breasted Chat, Yellow Warbler, Hammond’s Flycatcher, Black-headed Grosbeak.  To our south in the Shasta area a Common Nighthawk was reported.

Great conditions, clear skies and a nice tail wind – BOOM!  Heavy migration last night, all night.  The loop says it all.

Take a look at the wind map and you can predict the scenario.  Northeast – shut down.  Mississippi and Central – pile up in Texas and continuation behind the weather.  Pacific – open for business.

24 April 2015 — PNW Migration Update

Shorebirds continue to move through the area.  Found in those isolated spots with suitable habitat. I don’t think anything new, that hasn’t been mentioned earlier, has shown up in the area.  But i’ve been quite busy with other tasks and i may have missed something.

Take a look at the winds aloft plot and you can see a concentrated low has formed bringing cold air out of the Gulf of Alaska and turning the winds to a more favorable direction for northbound migrants.

Unfortunately there are associated rains and that always dampens determination.  But give a bird any break in the weather and they will take advantage of that.  I put in the HC plot today so it is easier to pick out the birds from the weather.  It looks like they had a few hours of flight before giving up for the night.

If you look again at the winds aloft plot one might surmise a continental scenario:  looking good for the Central Flyway, and not so good for the Atlantic.  So i put in a snapshot of the National Radar Composite to see if that is how it played out last night.

Winds Aloft Plot: Source

National Radar Composite: Source

17 Apr 2015 — PNW Migration Update

Yesterday the west side of Sauvie Island WMA opened — i was there at first light and did not take the time to post an update.  Just like the weekends.  Anyway, the migration that night was solid, but on the moderate side.

Unlike last night!  Green doughnut night with some returns in the heavy to extreme range.

Its getting hard to keep up with the migrant influx along the Pacific Flyway. In the Portland area: a whiff of Wilson’s Warbler, a hoard of House Wren, a pulse of Purple Martin, and a mote of MacGillivray’s  Warbler.

It looks like Paul has ironed out the kinks in the national composite radar archive.  So head over to take a look. The Mississippi Flyway, behind the front moving across the country, filled in nicely.  A Cuban invasion of neotrops hit Key West.  And the Pacific Flyway was lit up from San Diego to Seattle.

 

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.

10 Apr 2015 — PNW Migration Update

It was a Pacific Flyway party last night.  Heavy migration from San Diego to Seattle.  Birds definitely took advantage of the south winds associated with the leading edge of the incoming cold front.

I threw in a snapshot of the National Composite radar today for another look at the interaction of weather and migration.  With a big storm front draped across the central part of the country it is easy to see migration out in front of it and nothing immediately behind it.

A few more Purple Martin reports in the Portland area but that’s about it.  The big push is just around the corner as the Central Valley is loaded with migrants.

08 Apr 2015 — PNW Migration Update

There was a moderate amount of movement last night.  Birds were picking out opportunities between the rain cells.

Only listserve chatter of note comes from San Diego where Chipping Sparrows, Nashville, Yellow and Wilson’s Warblers, Yellow-breasted Chat, and Hammond’s and Western Flycatchers were reported.

Paul has his archive back on line after a few days of being down.  I’ve included a static shot of the action along the Mississippi Gulf coast line.  Looks like the neotrops are pushing their way north in good numbers.  Check out the full loop here

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02 Apr 2015 — PNW Migration Update

Scattered rain cells and the north winds on the back edge of this trough kept migration to a bare minimum last night.

Vanguard Black-bellied Plovers have made it to the Portland area.  Scattered Black-throated Gray Warbler reports are popping up.  Not much else.

The Central and Mississippi Flyways had the most action last night.  Probably the heaviest they’ve seen this year.  In the gallery is a snap shot but be sure to head on over to Paul’s archive and catch the whole loop.

 

27 Mar 2015 — PNW Migration Update

Excellent night flight, and as i write this it is still at full tilt.

Only new migrant reported that i saw listed was Purple Martin on the southern Oregon coast.

But tonight is one of those teachable moments on the interaction of the weather and migration.  So we’ll look at the conditions at 850 mb heights — note the stream lines and the ridge in the west and the trough in the east.  Then check out the static image of the national radar composite.  (The full loop can be viewed over at Paul’s archive: here)

The Pacific Flyway from the Mexican border to the Canadian border is solid blue with birds.  Everywhere else?  Central and Mississippi Flyways — nada.  Atlantic Flyway? — just a tiny bit on the SE coast ahead of the advancing cold front.

Big picture gallery today.

18 Mar 2015 — PNW Migration Update

The San Diego area is reporting the first Wilson’s Warblers and House Wrens and  Western Kingbirds and Bullock’s Orioles have made it into the Central Valley.

I’ve been keeping an eye on the National radar as well over on Paul’s archive.  I haven’t seen anything spectacular.  It’s pretty much all low density movement much like we’ve been seeing here in the Pacific Northwest.

But, birds are still moving north and you can see them dodging the rain cells in last night’s radar capture.