Mr. Great Horned Owl found close to the nest site…standing guard and watching for any intruders like Crows that seem too often mob a nest.
From what I’ve witnessed…when a nest is being mobbed the male will come in and try and drawn the attention to himself so that the Crows will follow him away from the nest.
During this the female becomes very vocal and loud hooting can easily be heard anywhere in the bush.

He now has his work cut out as there appears to be three hungry owlets to feed…along with Mama Owl.
Their diet consists mainly of rabbits and squirrels.

I’ve seen this before where someone has provided a nest for Great Horned Owls.
As Owls don’t do their own nest building and reply on other birds like Crows to do it for them.

Since Crows build a new nest each season…the old nest is there for the taking and will often be used by Great Horned Owls if in a suitable location.
These nests after being used in a second year are usually unusable again and a new location would be required.

Humans lend a helping hand by constructing nests for owls to use year after year…such is the case at this location.
Unclear just how long the nest has been there…but does appear to be very sturdy and should last a long time.