Even the sixty percent of people in New York who're OK with pigeons as a general thing sometimes find an up-close and personal encounter a bit distasteful. The major offense: Poop. Little pigeon poops accumulate and they are unsightly. Come summer, the accumulations do what guano does when left out in the sun — and most city-dwellers prefer a compost heap be elsewhere. Nature's own solution to the problem — a good rain storm — washes away accumulations on streets and sidewalks; rain somehow doesn't hit the balconies, terraces and windowsills all that well.
There are good solutions and there are bad solutions. Smart people adopt the former kind.
If pigeons are hanging out on your turf, it's not because they love you. Pigeons choose places they find congenial. It may be clean water. It may be shelter that feels right for them. It may even be food — but food alone is not generally as interesting a reason for hanging out as water and shelter. [Partial proof of this: If food is set out at specific times, pigeons figure this out pretty fast, arrive for a snack, hang out for “coffee & dessert” — so cosmopolitan... — then most take off for the next event in their busy day. Only a few habitués stay around.]
There is also the issue of companionship; pigeons do seek to hang with their buddies, sort of....
Wild-pigeon populations (none in the U. S.), mixed wild/feral populations (common in Eurasia) and feral pigeon kits (the correct term for large groups of pigeons — what we have in New York) are by nature cliff dwellers. They like height and they like shelter. They like warmer temperatures than we do — but really warm days mean greater thirst and a preference for shade. Pigeons are no fonder of drenching rain than we are; they seek shelter from it. On cold days, they will seek shelter from a wintery blast. While seed eaters by nature, pigeons seem to have adapted well to whatever is available; I have even seen them nibbling on remnants of Buffalo wings.
What does it mean for us? Among other things, it means that urban-dwelling pigeons like our terraces and balconies and windowsills in a general sort of way. Add any one element — being relatively undisturbed, Fido's or Puss's water bowl, a dish of cat-chow, flowers gone to seed — and pigeons will come to visit. Pigeons are curious about things; they will enjoy watching what you do; if they conclude you aren't scary, they will even seek your attention (“soon again I heard a tapping somewhat louder than before”). If one pigeon is happy, others will catch on and there you are, running a bird sanctuary.
In short, if you have pigeons hanging out around you, it's something you've done. You may want to blame someone else; it's so much fun to blame “them” for unpleasantnesses — people lie to themselves all the time.
That will not alter things. It's your own fault!
Lots of people will tell you lots of things about getting rid of pigeons. Most of them are mistaken in their view of things. Most of them have agenda; quite a few of those agenda include helping you slim down by lightening your wallet.
Windowsill-roosting is the easier problem to address. The best solution is pigeon-spikes. A couple companies make these, they are made of metal or plastic; they can be ordered on-line or locally procured at Home Depot. Depending on brand, the spikes are supplied in one-foot or two-foot strips. Some come in different widths; others have snap-together strips allowing one to make up different widths. The Bird-x strips I use come in one-foot snap-together units, are made of plastic and are readily put down using what appears to be a sort of silicon gel “glue” that can easily be removed if that is in order. I use the wider configuration to cover the full six inches of sill depth.
The idea behind spikes is not to hurt the birds. Quite the contrary; spikes are generally regarded as a fairly humane way to deny access. Essentially, in place of a stable landing area, the pigeon finds a prickly, wiggly surface as it tries to touch down. It aborts the landing and goes elsewhere.
[The principle holds for air-conditioners that stick out from windows, according to some spike manufacturers; create a “forest” of spikes covering the entire extended area and the birds can't land there. You really do want to do something like this; the idea of an A/C unit sucking in dried pigeon guano reduced to dust really is scary. A better solution, however, is to use a through-wall mounting, with no projection outside.]
Pigeon spikes are pointy and sharp. They don't really need to be, and a more diligent person will cut the points off. There is some — but minimal — risk of hurting the birds if this is not done, and a seriously hurt bird is not only a wicked outcome, but messy to correct. Metal spikes are more durable than plastic and the latter will need to be replaced with some frequency. If you don't cut the points off, it will not be a big deal, though. I've done it both ways, and no punctured pigeons yet, so far as I can tell.
Some care in installation is important. Pigeons are very good at finding ways to get between spikes. Leave a wide enough gap between spikes and window or screen, and you may will find a pigeon caught there. If it gets in and can't get out, and you leave it there, you will have a dead pigeon to remove — not nice, not pleasant. If through repeated landing attempts, the spikes bend or break (both more prevalent with plastic spikes), the pigeon gets back a relatively stable landing zone.
Spikes are a solution, but not a perfect one. A main weakness is, they don't completely deny the requisite landing zone to the birds. Pigeons are good fliers; it's a survival trait. This includes being quite capable of landing on vertical surfaces if there is something to grab onto. They are, taken altogether, quite smart enough to manage spikes. They are sturdy enough to “tough it out” and do a sort of Indian fakir thing along the bed-of-nails line. The spikes are a discouragement, merely. It helps if you close the blinds on that window for awhile; this reduces the curiosity factor (some pigeons are dedicated people-watchers).
Window screens, spaces between bricks — those sorts of thing is just as good a landing zone as a flat windowsill. The temptation is to place netting over such areas; this is generally a bad idea, however dearly loved by the “animal control” specialists (exterminators). Netting, if fine enough, does not remain fixed in place (consider our strong Tribeca harbor breeze). Birds — pigeons and others — get trapped behind it and die. Not nice. Not æsthetic. Not pleasant. Add to this, the netting is expensive and needs frequent, equally expensive maintenance. Well-beloved of “pest control” firms, but this is a good way to go broke.
So spikes, but some vigilance and scare-'em-off activity too: We have found a synthetic “feather duster” (we have a couple) waved in the face of a stubborn birdy will encourage rapid departure.
Balconies and terraces and so on present a much more difficult problem. Even with some kind of “parapet denial”, birds can come to visit. They will fly over spikes. They will fly over fluttering flag-lines. Passive denial devices — owl statues and so on — aren't scary at all. Active denial devices present their own problems: Electro-shock systems are too static, and too costly and may have unintended consequences. A resident raptor will do the job — but they tend to be messy eaters and cleaning up after them can be hazardous to eyes and fingers (goggles, shoulder-length gloves, other suitable attire is commonly recommended — and interfering with raptors involves potential problems with The Fed...).
The best way to discourage the birds is to use the space yourself. Some birds will come around where people are; most will not. It varies mostly from bird to bird, not species to species, in my experience; it also depends on how scary the person it. Generally, the more and the longer you hang out on your balcony, the less frequently the birds will hang out. For those who insist on being friendly, a wave of the feather duster (“pigeon communicator mark 1”; “pigeon communicator mark 2” is an automatic umbrella) or banging a couple empty liter-size plastic water bottles can be useful.
If birds come visiting and are comfortable, they will leave messes. Pigeons poop only when at rest; they digest food only when at rest. [Nannies in the local park discovered this the hard way; they kept sitting on park benches right underneath a favorite roosting spot. The Parks Dept. accommodated the nannies and their rich employers by cutting off the tree limb; one must not discommode a rich person's nanny.]
If the birds settle in, they will deposit little packages of joy. Cleaning up is not difficult, but it needs to be done and it can't be delayed.
We've found the best procedure is to use a hose taken from the kitchen tap to the balcony (which sadly lacks a spigot of its own) — about 35 feet long works just fine, with one of those nice old-fashioned marine-brass nozzles that adjusts with a twist. An easily found adapter allows connection between the disparate threads of kitchen faucet and garden hose. Water temperature should be warm, not hot.
The most important thing may be to be sure the balcony or terrace drain has a grate on it. Pigeons moult and drop feathers and so on; these have to be kept out of the drainpipe.
The wash-down process is pretty simple: Put on washable clothing. Use a cheap shower cap and a cheap face mask (the loop-end kind come 100 to a box in many pharmacies) and maybe some cheap gloves. If you wear glasses, fine; if not, craft goggles are good. This sounds like a lot of bother, and it is overkill most of the time — these are health department recommendations for serious decontamination, and that is (one sincerely hopes) not the case on a person's balcony. On the other hand, why not? Think of it as an adventure — or the urban equivalent of living in the 'burbs.
A wash-down of a fairly sizable balcony or terrace takes about 15 minutes. If there are stubborn areas — possible if the balcony is not smooth — a bit of work with a deck brush, and maybe some bleach will quickly finish the job, adding another five minutes or so.
The problem is rarely with the pigeons; the problem is us, ourselves, a deficiency in our caring for the world. Most people reading this won't understand that; it is a rather complex notion and requires a certain depth and breadth of familiarity with a whole lot of stuff which most people have no inclination to acquire. So, limit the matter to pigeons:
These birds are some of the big winners in the lottery of life; they are real survivors and know how to live in a world dominated by humans. Pigeons are also elegant creatures of style and grace aloft, and are otherwise beautiful to watch. Our world is brightened by them. Robert Johnston, “Feral Pigeons”, Kansas School Naturalist, Volume 45, Number 2, December 1998
Most especially, they are ours. We brought them with us, we made them over the way we wanted them to be. Many have freed themselves and their offspring from those origins and have learned to live with us. Accommodating them is not particularly difficult and the pleasures of their company can be an enhancement. The minor inconveniences to which we are sometimes subject are really nothing.