““I would like to know what happens to change the yearly pattern of animals.””
I would like to know that also Spunky.
When we first moved in here, we had tiny little toads everywhere at night fall.
My dog used to get right down and bark at them.
Then we had Monarch butterflies fly through our yard when they were migrating.
Last 5 years not a one.
We hardly have any bees anymore.
Strange.
No ducks in my area for the second year in a row and very few bees.
IMO, the 2 culprits are 5G Towers and Solar Farms.