Estimate the number of birds visible in this image - don't take too long! click on the image to swap to the counted version:- |
A small part of a huge flock of Sooty Shearwaters from Chimney Rock, Pt. Reyes Nat'l Seashore, Marin County, California in August - with thanks to Keith Kwan who provided the photo; I have provided two blocks of 500 birds (red; blue), a narrow central block of 100 birds (green), plus the balance of birds (yellow): |