Ring video doorbell

Hi all

I have the ring video doorbell 2nd generation. I’m currently using it as a battery operated out in my backyard on a table. I have my zones sets and high sensitivity but it won’t pick up things like birds even though they’re clearly in the zone detection. The other night, it showed i had a cat in my backyard which picked up the motion but didn’t give me the notification I also get squirrels and sometimes it will detect them but not always. Just curious to know if i am doing something wrong.