PATHOLOGY TEST 4 REVIEW - Logan Class of December 2011

(a)In a study of winter feeding flocks, 36 blue tits visiting a bird table were trapped, and before release each bird was marked by placing a small metal ring round one of its legs. The following day 43 blue tits were trapped. Of these, 21 were ringed. Estimate the size of the blue tit population visiting the bird table. Show your working. ................
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