Freeloaders

I can’t say I blame any of them. If someone put up 100+ homes in my hood and failed to put up a guard dog, I’d probably move into one of them, too. “Forget about your swallows, I got kids!” Of course, that’s just what many animals have done at our site. The white-rumpeds leave many boxes unclaimed, so somebody might as well take refuge. But even with all the empties, our swallows aren’t the baddest of the bunch. There are a couple other critters that muscle their way in.

For reference sake, this is the usual find in a box.

Newly hatched fish foo... err... I mean baby swallows

Unclaimed Boxes

Who else would our bird boxes be perfect for if not other birds? One pair of Cattle Tyrants lucked out. Usually they would not have been able to occupy our boxes because the holes are too small. However, the top of box 66 blew off, allowing this male and his mate to access the box through the top. The weather certainly didn’t treat their chicks well. Only one survived. Good cavity choice, smarties. Natural selection at work?

This brings up an interesting conservation point: regulating the use of nest boxes. Dr. Stanback in Davidson discovered that by limiting the nest hole size of his boxes, he is able to prevent the use of nest boxes by Eastern Bluebirds. This has allowed for other birds of interest, primarily Brown-headed Nuthatches and Carolina Chickadees, to occupy boxes in greater numbers.

This Christmas this guy can be grateful for poor craftsmanship.

With water all around, it’s not surprising that some hoppity herps (yea, I just said hoppity) have made their way up into our boxes. A shady spot with insects and no fish? Score one for the frogs. Sometimes we’ll find one, sometimes we’ll find ten.  But regardless of how many we find, they are always guaranteed to freak out when we open the door, bouncing against the walls like locos in straight jackets in a padded room.

I guess you can say we've got herps.

My least favorite squatter. This guy/girl/I don’t care enough to check its genitalia has been spending its days in box 117 in Trailer Park for the entire season. I’ve had somewhat of a vendetta against bats ever since they came after Phil in Australia (we still have unfinished business in the Wet Tropics). Even so, I have to admit that these guys are pretty cool (there are more species of bats than any other family of mammals) and very important to the ecosystem.

First you try to kill my boy, then you take my box? That's pretty weak, bat. Pretty weak indeed.

Not pictured: Saffron Finch


Usurpers

Not all birds play nice. The House Wren, a common species in the US and Argentina, is notorious for taking over the cavities of other birds. How does this small bird convince other birds to give up their homes? Simple. They poke holes in their eggs. Pretty dick, huh? Well, it works. Some areas in our field site are overrun with House Wren, such as Trailer Park and Wild Wild West. It seems they have some sort of a truce with the swallows, though, because few wrens nest outside of these two locations. Thanks, I guess?

While we’re on the House Wren, notice the nest. Anything about this nest different from that of the swallow nests? Uh, yea. House Wrens prefer sticks to grasses.  They will often build their stick nests tall near the cavity entrance and position their nest cup in the back of the cavity, making it more difficult for predators to reach in and grab their youngins. Pretty smart birds, aye?

This little birdie made his house out of sticks. But this birdie ain't afraid of any big bad wolf.

Some box hogs aren’t to be messed with. We go ahead and give these guys space, recording a ‘W’ in our log books and long dash through all the days of the season. What species of wasps occupy our boxes, you ask?  Well, I cannot say that I am an entomologist, or anything close, but we do categorize our wasp pests according to a very specific Golo classification system: big wasp or small wasp. These are the small guys, who pack their boxes with more brothers and sisters than the big guys. These buggers are at least nice enough to make their presence visible from yards away. The big guys, though? We usually don’t know they’re in a box until we open it up, or put our faces under the boxes to check, getting a face full of stingers.

(Note: As of yet, Maya is the only one to have been stung. Might that suggest I am more cunning and ninja-like? Most definitely. Will this post ensure that I get stung tomorrow? Bring it on, karma)

"Huh, what are those? Ants? Hey David, would you go check out that box and see what's in it?"

Screw you. You go check out that box.

Just plain assholes

Some birds neither evict our swallows nor take over empty boxes. Instead, they try to get the swallows to raise their chicks for them. You may have heard of this phenomenon, called brood parasitism, in relation to old-world cuckoos, but it is also common in cowbirds.  The type of brood parasitism exhibited by the old world subfamily of cuckoos is extremely interesting/bastardly. A female cuckoo will lay an egg in another bird’s nest, which hatches very quickly, before those of the host species.  After it hatches, the chick has innately begins to haunch its back and push, clearly the host eggs out of the nest. These unfortunate parents are then tricked into raising only the cuckoo chick. With cowbirds, brood parasitism isn’t so sinister. They do lay an egg in the nest of another species, ensuring that the host chicks lose out on much needed nourishment, but the cowbird chick does not evict the host eggs form the nest. How generous.

I know what you might be thinking: "Hey David, how do you know that is a cowbird egg and not a swallow egg?"

Oh I don't know, it's just a hunch.

Not pictured: Water rodents