Nest size vs. offspring return rate

ReturnNO = nest volume of nests with no fledglings returned to study site ReturnYES = nest volume of nests with one or more fledglings returned to study sit

Feeding effort vs. nest size

date 1 = 1st Ma

Nest size vs. nestling body weight

date 1 = 1st Ma

Nest size vs. brood size

Nest size vs. brood siz

Experimental nest size enlargement vs. nestling body weight

date 1 = 1st May; treatment: C = control, ZV = enlarge

Feeding effort vs. experimental nest size enlargement

date 1 = 1st May; treatment: C = control, ZV = enlarge

Chemical defence in avian brood parasites_raw data

Raw data obtained from the stud