[CT Birds] Estimating bird numbers - an exercise

Frank Mantlik mantlik at sbcglobal.net
Sat Sep 26 10:15:24 EDT 2015

Many of us struggle over quickly and accurately estimating numbers of birds in a flock. While conducting a Christmas Bird Count, how many Canada Geese just flew by? The numbers of Tree Swallows that roost at night along the CT River in fall are beyond comprehension. On a recent boat cruise, I heard estimates ranging from 200,000 to 1 million.  That's a large range of estimates.

Well, I just saw on the Maine birding list-serve (ABA Birding News) postings by Jan Pierson and Peter Vickery, providing a link to Martin Reid's website that has a terrific exercise in estimating flocks of birds (or butterflies, etc.). 
He provides numerous photographs of bird flocks in real-life conditions. Make a quick estimate, then click on the image to reveal the actual number; hit the back button to return to the next photo.

Give it a try. Practice makes perfect. Thank you Martin for providing this.
If you think you have a grasp on estimating numbers, then I dare you to estimate the number of Tree Swallows in my photos, here:

Good birding,
Frank Mantlik

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