Date: 8/31/20 9:34 am From: Thomas Gilg <tom...> Subject: [obol] Re: Vultures along Hwy 34
On my very recent Brownsville <-> Corvallis drives, the farmers were plowing/planting and kicking up epic dust storms, and ever since the seed/hay harvest awhile back, many small groups of vultures have been in the fields. At my home just outside of Brownsville, the vole population is way up this year, and very recently I’ve had several large groups of vultures fly over.
I don’t suspect anything sinister going on. Last year I met one of the farmers near the Tangent Eagle Roost, and was impressed by his knowledge of the bird populations over the decades, and his efforts to rebuild habitat that had been cut down and plowed under in prior decades.
From: <obol-bounce...> <obol-bounce...> On Behalf Of larspernorgren
Sent: Sunday, August 30, 2020 12:02 PM
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Cc: Oregon Birders OnLine <obol...>
Subject: [obol] Re: Vultures along Hwy 34
I noticed this at around 9:30-10am Saturday. Not sure l've seen so many Turkey Vultures in a field before. Concentrated on a carcass or dispersed. It's a perennial grass seed field, where vole populations can build up and attract concentrations of raptors. The ag field at Luckiamute Landing state natural area has been blessed with the voles this year, but so far only Great Blue Herons are pursuing them.
I too remarked on the absence of straw, hence evidence of recent machinery and attendant microtine mortality in the field between Corvallis and Tangent. Perhaps the vultures are attracted to voles that have been dead for awhile. The field at Luckiamute Landing state natural area has had dead voles of a certain vintage this season, occasionally revealed by bird banders' companion canines. I know that slug bait is sometimes applied to farm fields in Linn County, but have never heard of rodenticides. Not saying it wouldn't happen, but the profitability of the crop is so marginal that no one would spend an extra penny.
On occasion the vole densities are such that Buteos cease to fly, or even run, but waddle from vole to vole. I didn't pull over and watch. But l didn't see the Turkey Vultures moving at all. On a related note, l was at the Marine Science center trail before sunrise Saturday and saw at least half a dozen Turkey Vultures rise up behind Idaho Point and start flying about quite actively. 6am at the latest and still kinda dark. I always think of this species as taking to the skies around 10am. That's when thermal updrafts start to develope in the Willamette Valley. The north wind was plenty strong over Yaquina Bay yesterday to make a vulture's time aloft entertaining and effort free.
I'm enroute Corvallis to I-5. I noticed along the South side of the highway in fields that have been completely harvested there are lots of vultures on the ground. They are not congregated. They appear to be eating. This is not a recent harvest there's not any stubble the field looks like it's starting to refresh itself. My concern is that somebody is poisoning rodents and the vultures are feeding on them. Any thoughts?