Yes, it must be a lot of insects. The parents must be exhausted.

A few years back we had Crows that made a nest in a huge gum tree next door and
when the baby hatched it turned out to be a Pallid Cuckoo.

Pallid Cuckoos lay their eggs in the nests of other birds. Long story, but it was an
incredible thing to watch. The baby Cuckoo became larger and larger and these poor
Crows couldn't keep up with the feeding. We don't usually feel sorry for Crows here,
but they were so totally exhausted and this massive baby was larger than they were and
still was a baby. It was a relief for the Crows and all of us when the Cuckoo finally fledged.

.


I actually felt sorry for the Crows, because they ended up exhausted and with no babies
of their own.
When I was watching the Red Tailed Hawks from Cornell, the birders kept saying not to
anthropomorphize but it was difficult not to do that.
.