Last fall I noticed a brown squirrel lounging on top of my owl nest box. She was just opposite my kitchen window so I put my binoculars there so I could watch her.  Often she would be stretched out with her front paws hanging over the edge.

I built the box several years ago and hoped an owl might take up residence. I had had a bigger box that an owl moved into but it departed and left behind the skull of a squirrel plus four big eggs.  I don't know what happened to that owl. 

I do know I have owls because I have seen them, and one little screech owl inhabited one box for a month.  I would walk under the box and talk with him and he would look down at me with an owl smirk on his face. Then one day he was gone.

I would occasionally see Mama Squirrel going in and out of the owl box, sometimes carrying sticks.   Previously some kingfishers had nested in the box. This spring the birds came back and took turns looking in the box hole.  

I had not been too pleased with squirrels as they stripped my walnut tree in July and would drop the half-peeled green nuts in my fish pond. I decided to watch this squirrel and see what happened.  

One day two big grey squirrels, which are native to our area, came into the back yard. Apparently Mama was not letting them in. There was a scuffle and the “boys” left.  

If brown squirrels breed with grey squirrels, the babies will be black. Mama Squirrel's offspring were all born brown. 

Mama was going in and out of the box often. She also started taking short rests on the roof.  And I noticed that she was nursing babies. This behavior went on for about six weeks. One day I saw two babies on the side of the owl box and Mama trying to coax them to the roof.  After a day or two they made it on to the roof and would sun themselves with their mother.  

Most squirrels have a litter of four, but I only saw two babies at a time. They spent more time on the top of the box  while their mother was away. They would play and sometimes go up and down the tree.  

One day I saw one of the babies grooming his mother. At that point I said to myself, “How could I ever kick these kids out?”  Off and on throughout the summer, mother and offspring would appear on the top of the box. I also would see the little ones running around the trees and playing.  

The mother is very comfortable around me. On one very hot day she got under a hose I was using and got wet and spread herself out on a rock in the shade.   

Now Mama is still here but without the babies. I read that squirrels can have two litters a year, but I hope she is not expecting again. My neighbors will not be happy to have more squirrels, I fear. 

I've had my walnut tree removed, but when it was still with me, I tried deterring squirrels with fox urine. That did not work.  Another time I constructed a large plastic collar around the tree. Alas, squirrels are good jumpers and that didn't work either. If you have a serious squirrel problem, first read the pest notes on tree squirrels published by UC Davis. If you're still unsure how best to manage the critters, contact the California Department of Fish and Game and discuss the problem with them.

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