Can birds signal to one another?

[sydmayne]

After putting out some bread for the birds yesterday one bird arrived after about 30 seconds. A minute later the garden was covered by a whole flock. Can birds contact one another?

[lankeela]

They have incredible eyesight.

[funnywebsite]

Yes, they make whistling sounds to get the attention of others.

[andy hughes]

I think you'll find that although you can't see them, there are flocks of birs perched where they can see a large area of gardens, so as soon as they see one bird feeding, they all join in. In evolutionary terms, it's every bird for themselves, as food is often limited, so they would not be keen to invite others to join in.

[paddy_36]

I've noticed this too, but particularly with starlings. They don't like bird feeders much (although they don't give up easily with peanut feeders!) but as soon as I put food out on the ground, especially fat, hundreds of them seem to appear out of nowhere! They sit on nearby rooftops and chimneys most of the time, but it's definitely every bird for themselves when it comes to the food, as andy says.

[WendyS]

I suspect they're all quietly tucked away resting in high vantage points and the moment one bird homes in to a specific spot they all go on major alert, letting the first arrival take the risk of being ambushed. Once the presence of food is spotted and they discover it's safe, they all dive down. Although strangely in this recent frosty weather, despite putting out a variety of bird food every morning, we haven't seen as many birds yet as we would have expected. Perhaps they're all demolishing the neighbours' hawthorn and pyracantha berries first.

[Robinia]

It's funny how it happens isn't it? They seem to come from way down the street sometimes so I've come to the conclusion they now have little mobile phones!