Is this just a perception, or do birds actually aim for things when the crap? Seems to me that they crap when and where they want, regardless of what it lands on. Any research would be appreciated.
It is common behavior for some birds chasing something away from their nests. I have no cite for this, just first hand knowledge.
One distinct memory is of a sparrow who chased my friend and managed to crap right on the top of his head while he was running.
Well, my friend was walking through New Westminster Secondary’s stadium (total area about 11 acres) and got nailed right on the head by a seagull.
I’d say yes!
Certainly defecation is sometimes used as part of a mobbing tactic (where a bunch of (usually smaller) birds gang up and drive away a potential predator), but as to whether they intentionally crap on stationary objects such as parked cars, it is difficult to say; I suspect there are a number of factors involved, such as…
-Birds often seem to crap just as they are coming in to land; if this happens to be the roof of a house, then there’s a good chance their package will be deployed on one of the windows, or on a car parked alongside.
-Bird droppings that fall on the ground are easily overlooked, those that fall on a car window are not.
I recently saw a pigeon land on the sidewalk, crap, then fly off. First time I’ve ever seen this happen. I was fill with gratitude and admiration.
A true gentleman among pigeons.
I have a couple of feeders outside our den. One is is longish, rectangular and with openings sort of like church windows through which the birds feed.
If one bird is feeding, he might very well dump (which falls to the ground) as he eats. But if another bird is beneath him (i.e., eating from a lower window) he will NOT crap upon that other bird.
In the other “house-shaped” feeder, birds will go in the house, stand on seeds as they feed. They never ever crap in the house, even when the seed is very low.
What I guess I’m saying is they at least seem to control their urges. They observe hygienic ettiquette with regard to each other and literally do not shit where they eat.
In regards to birds “mob crapping” on larger predators as a defense mechanism:
I have an uncle who was at a beach eating a burger and fries. The seagulls continually flew closer and closer to the him trying to nab a fry. Like any inquisitive scientifically minded person would, he started feeding the fries to the seagulls out of his hands. In the intrest of further scientific inquiry my uncle decided it would be a great idea to grab one of the gulls as it took one out of his hands. (I think to test the psychological implications for this particular species of seagull of compounded stress levels while feeding during a receding tide phase.)
If I understand correctly, somewhere between 23 and a million seagulls swarmed to the vicinity to relieve themselves in the general direction of the experiment.
That’ll ruin one’s meal!
My pet birds clearly at times would delibrately crap on an object, a person who had just told them “no!”, or, during arguments, each other. One of them we taught to crap on command (this was useful if you were introducing to a new person - have the bird crap before letting them stand on the new person and they’ll be “safe” for about 20 minutes) and developed a habit of crapping just before hopping from his perch to a person.
So, birds have some awareness of this bodily process and some control. However, they can’t “hold” it nearly as long as a mammal can. About 20-30 minutes seems to be a limit, which is one reason it’s so darn hard to really “housebreak” a bird.