i94 
THE CUCKOO’S SECRET 
claim) of an intended Meadow Pipit’s. Another 
instance is given in the preceding chapter when a 
Reed Warbler Cuckoo was forced to use a Lesser 
Redpoll’s nest, which, owing to the recent destruc- 
tion of the nests of her natural fosterers for one of 
which she had “ conceived ” her egg, was the only 
nest in suitable condition near at hand. 
Once an egg has reached a certain stage of 
development the Cuckoo is of course compelled to 
lay it, and this is quite sufficient to account for 
many of the unusual dupes which are recorded 
from time to time. There must, of course, be 
occasions when the intended fosterers nest meets 
with some accident between the original discovery 
and the laying of the Cuckoo’s egg. 
The accounts already given of our experiments 
with dummy nests prove that Cuckoos must 
blunder perhaps more often than might be supposed. 
Searching laboriously for the nest that she knows 
ought to be somewhere near, she comes across 
another nest in suitable condition and makes use 
of it for her egg. 
It is possible that dominating Cuckoos may also 
be instrumental in causing a Cuckoo of submissive 
temperament to use a nest other than she intended. 
Take the case of Cuckoo R depositing her egg in a 
