Why Birds Poop in the Pool, on the Car, etc.

What’s the first thing that comes to mind when you hear the term “fecal sac”?

If you answered, flaming bag of dog poo, you’ve probably spent at least a little time in juvi. If you said the excrement of nestling birds neatly surrounded in a membrane, you probably have a field guide and binoculars on the window sill.

This week I’ve had several calls complaining of blackbirds pooping in pools, on cars, and my favourite, on a glass patio table. Most complainants were looking for a kill free solution, to some it didn’t matter.

The droppings were described as extra-large and white, some even noticed the birds were carrying it in their mouth and “dive bombing” these cherished objects. What they were seeing was the adults carrying the fecal sacs from the nest and getting rid of them where they assumed they wouldn’t be noticed by predators, unfortunately by doing so they likely created the most dangerous predator of all, the angry home owner. The pool is easy to figure out, drop the poop in water, it washes away nobody knows were it came from. The car table and other shiny objects look like water to a bird, much the same way a wet road resembles a river to a loons and sea ducks. Other birds maybe are fooled too, but these guys can’t take off from dry land, so we tend to notice them on the road. A mallard or goose would simply shake off the road burn and fly away. Loons and sea ducks need to be moved to water so they can take flight. (Tip: If you’re called upon to pick up a loon on the side of the road and will be doing so alone, take that extra couple minutes to dig out the cat carrier. It’s kind of distracting to drive with a loon under one arm pecking at your face and “area”.)

The good news is, poop bombing only occurs for a short time, as little as 10 days and 21 days at the most, depending on which species you’re dealing with. If the blackbird is nesting in a tree, it’s likely a Grackle and I’m not sure what you can do about it, my line is more attracting birds. If the blackbird nest is in a bird house, your eve or other cavity, it’s likely a European Starling and you can at least prevent future nests by making the hole in your bird house smaller, (drill an inch and a half hole in a piece of wood and nail it over the hole) or fixing the holes in your eves.

The bad news is starlings are capable of having a second brood, so get those holes closed up as soon as the young leave the nest or you’ll have a repeat performance a few weeks down the road.

The contents of the fecal sac are white from the kidneys’ contribution, birds don’t have a urinary bladder so the nitrogenous waste is excreted with the feces through the multipurpose cloaca as uric acid. This doesn’t dissolve well and the crystals form the white pasty part we see. For any of you who’ve had an unfortunate experience with gout, it’s the same crystals that converge in your big toe to cause so much discomfort.

The nestlings waste is contained in the sac until the last couple days of nesting, that’s when things in the nest start to get a little messy. I wonder if it’s natures way of telling the youngsters it’s time to leave. “Mom, Dad, I don’t really want to go but this place stinks...my eyes are burning! So if you could just bring my dinner to that branch over there?” I also wonder if not cleaning up will work on human offspring when the time comes, but I’m betting he’ll be able to live with it longer than us.

When doing breeding bird surveys, spotting an adult carrying a fecal sac is a great sign that nesting has been successful in the area. So a bird flying over with a mouth full of poop is a good thing, unless you or your belongings are the target. I’ve never had the misfortune, or at least I haven’t noticed, but my vehicle is white, maybe it’s covered with bird poop. I can understand why people want to discourage this activity. Have you ever noticed how often a bird poops? Watch a perched hummingbird really close some time, they go every 30 seconds. Most birds aren’t quite that regular but they do go often, no sense carrying that extra baggage when trying to take flight. A nestling bird produces the fecal sac within seconds of being fed, so the amount of live ammo being produced is approximately equal to the number of trips made to the nest with food.

At the end of one of the conversations about getting rid of blackbirds, I was asked, “How can I attract orioles?” It’s funny how one of the blackbirds is considered a pest and another is sought after. Although starlings and grackles are quite beautiful if you stop and take a close look, they don’t compare to the shocking bright orange of the male Baltimore Oriole. That and the fact they aren’t around very long or in large flocks like the other blackbirds, at the most you’ll see 3 or 4 in May and June while passing through. Some people are lucky enough to have a pair set up house keeping in their yards and are treated to the sight of their large gourd-shaped woven nests. Sightings at feeders are usually in the early season, most of us saw our first oriole when it easily flipped the bee guards off of our hummingbird feeders and sipped nectar.

If you want to draw a few more orioles into your yard, place a few orange halves in an open area where passing birds are likely to spot them. Orioles do seem to be attracted to the bright orange oriole feeders, but if you have a hummingbird feeder with large enough holes after the bee guards are removed they work just as well, then after they move on you can still use it for hummers. Orioles also eat seeds, favoring peanuts and hulled sunflower, suet and they love grape jelly. A few weeks after arrival they desert the feeder station in favor of natural food, mostly insects. The orioles that show up in fall don’t use the nectar feeders but will glean grapes from vines or fruit feeders.

I’ve been reading that orioles will take meal worms during nesting season to feed their young, another good reason to start raising your own worms.

A couple weeks ago I mentioned the Common Yellowthroat that was our predominant nesting warbler until a few years ago had hopefully moved on after our trees matured. I was in Upper Coverdale last weekend and heard several males singing. This week we also have a couple males singing within earshot, except now they are on the other side of the house in an old pasture that’s growing over with trees. We still have the Northern Parula and Black-throated Green Warblers singing steadily, with everything else it sounds almost orchestral.