[Why do] birds [sing at dawn?]

Why do birds sing at dawn?

PBS has a nice article on bird songs:

They’re trying to hook up to mate. Broadcasting their location makes them vulnerable to raptors. At dawn, they are more difficult to spot from above, but if a potential mate shows up, it will soon be bright enough to find eachother.

Only rarely. The majority of birds have a fairly short breeding season, yet the majority of birds sing year-round, so clearly it’s not to attract mates.

Most birds sing either to define their territories as part of their defence against rivals, either groups or individuals, or else to simply announce their presence to other members of the same species and reinforce their place in the pecking order.

Do you have any evidence for this? Most diurnal raptors hunt primarily by sight, so I doubt that sound pays a very big role in detecting prey. More importantly, raptors are most effectively avoided by simply sitting under cover, which is where most birds sing from. While it’s true that some birds will sing from positions that are highly exposed, it’s not the norm, and I doubt it makes them more vulnerable than when they are feeding.

Any evidence for this? My experience is that dawn is the *best *time to hunt animals from above. Not only does the warming air carry your scent upwards away from the prey, but the diffuse light of pre-dawn and the low-angle light of dawn both dispel shadows in the understorey. In contrast, during the middle of the day the sunlight strikes the canopy directly, creating a high contrast between the leaves and the understorey that makes it almost impossible to see animals beneath trees or or in long grass.

But note that few birds have any sense of smell.

Title edited to indicate subject.

Maybe in Australia the majority of birds sing year round, but it’s not true world wide. In the temperate zone of North America, most birds don’t sing much if at all during the non-breeding season, and there is no real dawn chorus. Even in the tropics where breeding seasons may be prolonged, there are times of year when there is very little singing activity by most species.

It might be mentioned that ornithologists often make a distinction between songs, which are usually more elaborate vocalizations given to attract mates or defend territories, and shorter, simpler calls which are mostly given to maintain contact with a mate or flock member or in alarm.

In my opinion, the main reason that song is most intense near dawn is because that’s when the day’s activities start for most birds. They want to advertise their position for potential or actual mates or territorial rivals. Once that general position has been established it can be confirmed by less frequent singing later in the day. There is another, smaller peak in singing/calling activity near dusk, when birds are going to roost, for similar reasons. While not as distinct a peak, calling by night birds like owls and nightjars may be most frequent just after dusk when they begin their activities.

The mockingbird in my neighborhood sings in the middle of the fucking night.

There are some species of day-active birds that sing at night. One idea, already alluded to above, is that males do this to demonstrate to females that they are in such good condition that they can afford to expend energy in singing even at times when they don’t have any food available.

Does human-created artificial light simulate dawn or pre-dawn conditions sufficiently to cause birds to sing or call in the middle of the night, i.e., at times they would otherwise have been silent?

In other words, are the birds that trouble us by singing at midnight doing so because we’ve bombarded them with too much light?

Because just like me, they long to be … getting laid.

No. Mockingbirds and nightingales sing at night even when there is no artificial light. I have never noticed birds that typically sing at dawn singing fooled into singing at night due to streetlights or other artificial lights.

Do you sing at dawn? For a lot of humans, that’s going to be counterproductive…

Highly ironic user name/post content combination.

I don’t know, but I do know why the caged bird sings

At this point I’m willing to try anything.

Hell with that, I want to know why birds sing so gay.

I’ve heard that the mockingbird (I use mockingbird as an example because it is the most notorious for doing so) sings at night if he hasn’t yet found a mate. Those who have mated have no reason to sing at night. Who would kill a mockingbird even if he wakes you up at 3AM?

Because other little birds are starting to become active and they need to be told to STAY OFF MY LAWN!

IANAO

le whoosh, I believe…