But 100,000 = 500,000/5 (5 was your number), and not 500,000/6 (6 was 
Maurice's number)?

Good birding,
Richard


>From: Cliff Comeau <>
>Reply-To: Cliff Comeau <>
>To: 
>Subject: [MDOSPREY] Large blackbird flocks
>Date: Sun, 28 Jan 2007 17:06:40 -0500
>
>As an engineer, I have to respond to physicist Maurice Barnhill’s posting 
>to DE-bird January 25 about estimating the size of a large blackbird flock. 
>December 29 I saw a large flock of blackbirds along Egypt Road on the way 
>to Blackwater NWR. My 2 sons and a grandson were with me. I reported the 
>flock on MDOsprey as 100,000 birds, which I considered a conservative 
>estimate. Those with me were guessing several hundred thousand.
>
>It is difficult to think back in retrospect and estimate the dimensions of 
>the field where most of the flock was for part of the time, but I think 
>1,000 by 500 feet is reasonable. I reduced the area required by each bird 
>from 6 (Maurice’s estimate for grackles) to 5 square feet, since about half 
>of the flock were Red-winged Blackbirds and Brown-headed Cowbirds, the rest 
>Common Grackles. Interestingly enough, doing the math that Maurice 
>suggested yields 100,000 birds.
>
>This is still a conservative estimate, as thousands of birds were always 
>flying or perched in trees along the field edge.
>
>
>Cliff Comeau
>Beltsville, MD
>

_________________________________________________________________
Search for grocery stores. Find gratitude. Turn a simple search into 
something more. 
http://click4thecause.live.com/search/charity/default.aspx?source=hmemtagline_gratitude&FORM=WLMTAG