Date: 9/22/17 4:13 pm From: Frank Enders (via carolinabirds Mailing List) <carolinabirds...> Subject: Re: [Va-bird] large Cowbird flock, Fairfax County 21 September
On September 20, I was looking for the odd shrike here and there, only to encounter a stream of bunches of cowbirds flying low southwest (4 PM) over Grapevine Road near airport road into a herd of cattle.
More than 150 cowbirds, and only cowbirds, as this post by Stephen Johnson described in grass the next day in Fairfax County (Chantilly) VA.
As he said, no other "blackbird" species, and a big number, probably migrants.
I had thought "Wow, that is a lot of local cowbirds gathered together." But, I think he is right, migrants. Now.
Frank Enders, Halifax, NC
________________________________ From: va-bird <va-bird-bounces+fkenders=<hotmail.com...> on behalf of Stephen Johnson via va-bird <va-bird...> Sent: Thursday, September 21, 2017 8:46 PM To: VA-Bird Subject: [Va-bird] large Cowbird flock, Fairfax County 21 September
Fall migration brings many surprises. Today at the Cub Run RECenter (Chantilly, Fairfax county) I found a single flock of over 200 Brown-headed Cowbirds. It was unusual for 2 reasons.
One, eBird flagged it for the large number, and I'm not surprised. I was amazed to see them all in one place. Well actually two places. Half were in a grass strip separating parking lot lanes; and the other were maybe 40 meters away, in grass at the edge of the lot.
I studied the flock carefully, and that brought up reason #2. There was not a single member of any other species, in either half of the flock. I'm used to seeing big migrating groups of mixed Starlings and Cowbirds, and often there's some Grackles, and/or a few Red-winged Blackbirds. Here's the checklist. The Starlings listed were not part of this flock.
I have been seeing lots of young and adult Starlings recently, and ditto Grackles, so I'm pretty familiar with them; so I'm sure I was not seeing any of them in this flock. Very unusual in my experience, a pure-species Cowbird flock. The count is conservative - there were at least 250, maybe 300 birds present.