[obol] Re: swallow roosts

[David Bailey]

#6 on the radar image (http://empids.blogspot.com/ ) is centered 
directly over the Sandy River Delta (under Mt. Hood National Forest 
ownership). I would guess the birds are roosting in the Cottonwood 
trees. Couldn't some of these images be from birds other than swallows, 
such as E. Starlings? Still, very interesting either way. Thanks for 
sharing this Floyd. I hope someone will get out there to see the event 
first hand.

David

David Bailey
Seaside, Oregon
baileydc at pdx.edu
>  *Subject: Fw: Swallow (or martin?) roosts seen on radar in N. Oregon*
>  From: "Floyd Schrock" <fschrock AT macnet.com> Date: Mon, 11 Sep
>  2006 18:55:37 -0700 Obolinks:
>
>  Following is some new info from the Purple Martin recovery biologist,
>  including some NEXRAD evidence that there are other Barn Swallow
>  roost sites here in the northern Willamette Valley.  He is hoping
>  that Oregon birders might get interested in trying to find these
>  sites, and possibly find Purple Martins roosting with them; most
>  likely at the site along the Columbia R. east of Portland.  If
>  interested, please read his message below, and take a look at the
>  NEXRAD image that has six locations marked.  One of them might be in
>  a cornfield near you!  Please keep in mind that the flocks are very
>  difficult to find in the morning, since they depart so quickly.
>  Following them as they stream slowly into the area in the evening is
>  much easier.  The image is at: http://empids.blogspot.com/
>
>  ===================== Floyd Schrock McMinnville, Oregon  USA fschrock
>  AT macnet.com
>
>  ----- Original Message ----- From: Bruce Cousens & Charlene Lee (PuMa
>  Coord.) To: Floyd Schrock Sent: Monday, September 11, 2006 1:28 PM
>  Subject: Swallow (or martin?) roosts seen on radar in N. Oregon
>
>
>  Hi Floyd... Attached is an annotated NEXRAD radar image from dawn
>  (6:32 am) this morning with the latest swallow/martin premigratory
>  roost site information. There now appear to be 6 radar-detectable
>  roost sites in the Portland-Salem area, 5 in the Willamette R. valley
>  and one on the lower Columbia R. (possibly with others too small to
>  see on radar). This suggests the numbers in the area may still be
>  building up.
>
>  Site #1 is your original large Barn Swallow roost in the cornfield
>  off Nichols Rd., SE of Dayton (prominent dispersal signature at 7 am
>  also attached). The others are numbered in order of detection from
>  monitoring of NEXRAD weather radar imaging here and may also contain
>  BASW, other swallows or possibly Purple Martins. All had ceased to be
>  visible on radar by 6:50-7:00 am. At least some of these are likely
>  BASW satellite roosts, but we need ground check info before the birds
>  leave on migration shortly to determine the exact locations, habitat
>  used and species present (with photos of the habitat used in
>  daylight if possible for reference). I'm particularly interested to
>  know if Purple Martins may be using any of these sites.
>
>  Following are the approximate locations of the secondary roosts from
>  available radar base mapping and comparison with Mapquest and/or
>  Google Maps:
>
>  #2) Just E of Dundee, ~1 mi S of Newburg, adjacent to the Willamette
>  R., in Yamhill Cty.
>
>  #3) ~8 mi due S of Salem, 6 mi SE of Independence, 7 mi SSE of
>  Monmouth, likely in Lynn Cty., between the Willamette R. and Santium
>  R. - this roost is small, dispersed quickly or at low altitude (below
>  the radar) and was barely visible this morning, so location info is
>  approximate. It may be a different species and/or declining due to
>  departure on migration or movement to one of the larger roost sites.
>
>  #4) ~1-2 mi N of Forest Grove, near Hwy 47, in Washington Cty.
>
>  #5) ~2 mi S of Forest Grove, near Hwy 47, in Washington Cty.
>
>  #6) Just E of Troutdale (E edge of Portland), on the Columbia R.,
>  likely either E of Beaver Cr. estuary or possibly on Gary Is., Reed
>  Is., etc., in river. This could also be a Purple Martin roost, given
>  the numbers nesting in boxes along the lower Columbia R. in recent
>  years.
>
>  Please post this update to OBOL with a request for assistance so that
>  other birders may be able to help provide the ground check info
>  needed to confirm locations and species present. If the attached
>  graphics are not also posted to OBOL, you're welcome to post them to
>  your blog site with links to them from the OBOL post for reference.
>  Thanks.
>
>  Cheers,    ...Bruce
>  ______________________________________________________ Bruce Cousens,
>  B.Sc., M.Sc., R.P.Bio., Senior Biologist, BC Purple Martin
>  Stewardship & Recovery Program Coordinator, Georgia Basin Ecological
>  Assessment and Restoration Society #133 - 4176A  Departure Bay Rd.,
>  Nanaimo, BC, Canada  V9T 4V7 Phone/msg./fax:  (250) 758-2922; E-mail:
>  pmartins AT island.ne