Its all about caterpillars

Yellow-billed Cuckoos tend to spend a lot of time sitting still, just looking around. At first this might appear to be a somewhat inefficient behavior, however, every now and then they spring into action, lunging at a camouflaged prey item. When they do grab something it tends to be a big juicy caterpillar and it becomes clear why they invest so much time just looking. These large, nutritious caterpillars are excellent fuel for cuckoos as they prepare for long migratory flights and it is likely that much of their migration strategy is timed to coincide with the mass emergence of certain species of caterpillars.

Can you spot the caterpillar below?

 

By identifying which caterpillars cuckoos eat and on which trees the caterpillars depend, we can start designing cost-effective ways of increasing the food supply for migrating cuckoos in largely agricultural areas by recommending the inclusion of trees in live fences, for example.