You have described very typical bird behavior regarding feeding (they kinda come in waves, even though we have "somebody" around most of the time) and def. when the bluejays warn with that JAY! JAY! JAY! and everyone disappears, there was a threat of some kind, usually raptor... (though at times we've seen the feral cat be the culprit of a mighty warning)

I don't get mockers up at my elevation except when the berries come on in the fall/winter but I do have nesting catbirds, so I'm not surprised to hear they have different feeder habits. Don't know if mockers will go for orange halves and grape jelly or not (catbirds LOVE grape jelly).

Sounds like you definately had a hawk visit, and by the way you described it I would guess a Coopers or a Sharpshinned hawk. You will learn the more you watch birds that there are different levels of threats. In my yard/area a cat is barely a concern. I think this is because there are so many different feeding areas here and so many pairs of bird eyes watching them. Basically my birds reaction to a cat is to move higher up in the tree if they are in the same area as the cat. Everyone else goes on feeding as usual I've also noticed that the birds have different reactions to different hawks. Harriors get no reaction. They fly the fields in search of mice and rabbits and the birds never react when they are in the area. A redtailed hawk will get them a bit more nervous if they actually come into the yard and perch in a tree. They stay in the area, stop eating, head for a tree or stay in the one they happen to be in, they are aware of the hawk but not very worried about being lunch. Kestrels (also known as sparrow hawks) are in the area often too. Most often the birds have no concern about them either. They seem to Know if the kestrel is hunting them or just after mice or grasshoppers. Coopers and Sharpies are deadly though. Mega repect from my birds. Like you described in your situation, everything goes silent and birds instantly dive for the deep cover. A yard full of birds can "disappear" in the blink of an eye.

One thing that I have learned is to NOT go outside if I am aware that a cooper or sharpshinned hawk is there. I've had birds flush from trees because they saw me and the hawk will take advantage and pick that opportunity to attack.

I basically see the same thing. I'll add predators that require the element of surprise, cats, owls, etc, usaully get mobbed when present. Robins and Jays will follow the threat from about 5-10 ft away squaking the the whole time to announce their presence. I have an 18 y/o deaf cat who care less about the birds, but the Robins still mob her. She likes to lay under the trampoline in the summer and the Robins will come to the edge of the trampoline and squak. A mama Robin almost attacked her last year when her fledgling was scared by a passing truck and ran towards the cat. Mama came within a foot of my half-sleep deaf cat and startled her.

But when the neighborhood Cooper's hawk comes in the yard, it's usually hours before the birds feel confident enough to return.

Yep, agreed on the Coops and sharpies... a red-tail can sit almost on the feeders and the birds don't care once they know that's who it is...(looking for chipmunks in the brushpile :-)))) RT's just aren't fast enough to make the passerines on their daily menu, though that changes in hard times during winter when they will try for anything that moves, and the birds know it.

Sounds familiar. I have a Cooper's Hawk visiting regularly, and the Blue Jays and sometimes the crows will give the warning calls. Most of the birds will fly off, except for a few that freeze in place. Some of them will come back within a few minutes of the hawk's departure (it's a daily occurrence for them).

If the small birds are gone, but the squirrels are still bouncing around, I figure it's a Cooper's Hawk. If the squirrels are in the trees spluttering, then the neighbor's cat is hunting (or my old declawed cat is trying to sleep on the deck).

Occasionally a Red-tailed Hawk will enter the local air space, and the crows will mobilize like a fighting squadron. Much cawing and dramatic swooping and diving - the crows are very adamant in their hatred of Red-tails. They also seem to have a very tense relationship with the Cooper's Hawks.

Claire

It's been a while since I've been on these boards and have spent all afternoon catching up. Saw this message and had to post.

Just this morning a sharp-shinned flew into my neighbor's yard and I remember moments before he did - how quiet it got...

But then later, as I was still sitting out on my patio, out of nowhere over the house comes the hawk again and straight at my feeder! Birds scattered very quickly and all escaped successfully but I didn't notice any warning call or any quiet prior to his fly-in. It's certainly impressive to see just how fast they can fly if they have to. Just like OhBlueBird said, "A yard full of birds can "disappear" in the blink of an eye."

Just had to share my story too. I love seeing the raptors. I realize sometimes little birdies will be lunch but that's nature. And I'm ok with that.

Years ago I volunteered at a smaller zoo in Texas and worked with an RT. Ever since I've been just completely in awe of raptors in general. Where I am in Texas I see RTs, Mississippi Kites, Sharp Shinned and I even had a Barred Owl land in my tree twice.

I think the bird behavior opinion/advice is right on. I'm by no means an expert bird watcher but I seem to know more than my friends. ;)