That's called mobbing. The owl is being mobbed by crows.
A group of crows is called a murder.
A murder ( a large flock) of crows are mobbing ( action, as to what they are doing ) the owl
Blue Jays are known to mob owls along with the crows as well. Just yesterday while doing our yearly Christmas bird count with my Audubon group, there were a dozen crows making a racket. I told the guy with the big camera the crows were mobbing an owl. He did not believe me since we were in the middle of town. I told him to get his camera ready and I walked closer to the crows. Within a few second a great horned owl flushed from the pine tree. He thanked me later for getting some great flight shots of the owl 
This reminds me of the scene in Alfred Hitchcock's 1963 movie "The Birds". It was the scariest movie I'd ever seen at that time.
Well Terri, the Snowy owl is back and so are the Audubon people. You are right, it is extremely rare to see one this far South, if ever. The last few nights he has been on house roofs a street over from me. There is a constant flow of bird watchers with their cameras. In fact he/she made the local newspaper. According to these people the last sighting of one was over a 100 years ago in Central Park, NY as the Southern most point.
I'm sorry but I had to document your sighting since it was a great photo leaving no doubt of it being a snowy. The friend I first told about it said never in her life time would she see one. So I sent your photo. In the birding world when there is a bird you have never seen it is called a lifer. Die hard birders are known to go over a 1000 miles to get a dependable lifer. By now there should have been over 200 birders to see your snowy. You have no idea how happy your owl has made people. It is probably known as the Parley snowy since that is the only info they had. Hope you have a happy new year.
Thank You Terri for the reply. When I went on my early morning walk today, I saw maybe 12-15 people in the neighborhood. I did not think too much about it at the time. I normally see maybe 0-3 people out walking around. Now I know why. Hahahaha. They were out scouting the neighborhood looking for the owl. They finally found it. I noticed that he likes to be on a roof top with something behind him for protection. Could be a roof vent or a raised chimney screen. Some are speculating that he/she came into the Los Angeles harbor on a ship or maybe he/she got loose from somewhere like someone's cage. The owl is so far South from its normal range that they think the owl had help getting to this part of the country. Thank you for alerting me to how rare it is to see the Snowy Owl this far South.
I told you your owl is a really big deal! Birders are really good down to earth people. Hope you get to know one of them.
I have talked to a few of them. All nice people. I just hope he does not land on my roof.
You got some great shots of the owl. You could make a small fortune with T-shirts. All it needs to say is: I saw a Snowy Owl in Cypress CA with a photo below.I have talked to a few of them. All nice people. I just hope he does not land on my roof.
You're famous! ; )
Your owl did not have help getting to CA. About every 5 years we gat them in OK. One year we had 11 in our state. I hope to photograph one if one arrives here. I'd love to see a male, they are solid white. Just beautiful with their golden eyes. Here's a male snowy in flight. Now that the word is out, there should be more owls noticed. Owls like to have the highest perch in the area. So whom ever has the highest roof should get the most activity. I just hope some idiot doesn't shoot her/ him. Yours is either a female or imm male. The female is noticeably larger than the male.
