David Lack did some interesting work with Starlings

He banded baby starlings in the nests and then tried to recover them after they fledged.

�clutch size
# nests
% recovered 3 mo. later
productivity (= relative % recovered
1
65
0
0
2
164
1.8
3.7
3
426
2
6.1
4
989
2.1
8.3
5
1235
2.1
10.4
6
526
1.7
10.1
7
93
1.5
10.2
8
15
0.8
6.4
9
2
0
0
10
1
0
0

Other studies have shown that young starlings with optimum body weight come from nests with clutch sizes around 5.

SO WHY DON'T ALL STARLINGS LAY 5 EGGS? WHY DOES SURVIVAL DECREASE IN SMALL NESTS?


European Starling

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