102 THE BOOK OF A NATURALIST 
One need not take it for granted that these strange 
vocal noises are nothing but love calls. They may 
be in part expressions of anger, since it is hardly 
to be believed that the members of these rude com- 
munities invariably respect one another’s rights. 
We see how it is with the rook, which has a more 
developed social instinct than the lonely savage 
heron. 
During incubation quiet reigns in the heronry; 
when the young are out, especially when they are 
well grown and ravenously hungry all day long, 
the wood is again filled with the uproar; and a 
noisier heronry than the one I am describing could 
not have been found. For one thing, it was situated 
on the very edge of the wood, overlooking the green 
flat expanse towards Breydon Water, where the 
parent birds did most of their fishing, so that the 
returning birds were visible from the tree-tops at 
a great distance, travelling slowly with eel and 
frog and fish-laden gullets on their wide-spread 
blue wings—dark blue against the high shining 
blue of the sky. All the young birds, stretched up 
to their full height, would watch its approach, and 
each and every one of them would regard the 
returning bird as its own too-long absent parent 
with food to appease its own furious hunger; and 
as it came sweeping over the colony there would 
be a tremendous storm of wild expectant cries— 
strange cat- and dog-like growling, barking, yelping, 
whining, screaming; and this would last until the 
newcomer would drop upon its own tree and nest 
