Owls and Eagles galore!

I have been following 4 eagle nests and 4 owl nests this spring with all of the owl nests (3 Great horned owls and 1 Barred Owl nest) successfully fledging their young and 3 out of 4 eagle nests with eaglets still in the nest. The 4th eagle nest had both parents in the nest for quite some time (see photos), but now there is only one eagle hanging around and no young. Last year, the female was found deceased in the nest from rodenticide poisoning according to Mass Audubon. Hopefully, that is not the case this year. Waltham, MA.