Well, I’ve never seen or heard of anything like this before: a building of sequential nests on top of each other, with the first ones uninhabited. This comes from the Erie Times-News in Pennsylvania via alert reader Mary.
The story first:
Camille Hardner has a few guests living on her porch — a family of robins living in five nests stacked on top of each other.
Hardner, of East 29th Street, said the parents built the five nests, one on top of the other, before the female robin laid her eggs. “It was quick. The pair built five nests in two days,” Hardner said. “Maybe she was trying to get out of the wind.”
Hardner said she believes it is the same pair of robins that built a single nest on her porch in 2013.
“I haven’t yet had anybody tell me that they have seen a robin build more than one nest,” she said.
Have a look; there are two large chicks. And, if you know something about birds, provide a hypothesis. (Wind sounds okay by me.)
How do they know it’s five nests, and not simply one very tall one — or ten very short ones?
b&
Looking closely, I can make out five layers.
I could make a much stronger argument for two layers and a divider, or for ten layers. It’s one of those indeterminate things that any count is plausible, depending on how you define, “layer.” And, thus, the real question comes down to: what is a layer? Lacking an answer to that question, counting them makes no sense….
b&
With respect, I disagree.
Going up the left hand side I can see five transitions four transitions between nests.
Since I knew the answer going in, I admit I’m at risk for pareidolia, but I also know what a bird’s nest looks like, and I don’t need to a philosphical definition of “layer” to see what I see.
I had something like that at my house years ago. A pair of robins built a nest over the floodlight in front of my workshop.
It looked like three layers after it was done but, as I watched them build it, it was just them going and going until they stopped and put four eggs in it.
It ended in tragedy. The four babies got bigger and bigger and fatter and fatter until the whole thing unbalanced one day and over it went. I doubt that the fall killed them, it wasn’t that high. More likely the parents brains could only accommodate the idea that they needed to stuff the squawking things in the nest. What are those squawking on the ground? Meaningless noise.
Sorry to hear.
I wonder if these birds and yours might be young and inexperienced in the ways of nest building. Perhaps they’ll learn from their mistrakes?
b&
Ben,
I’m guessing that they did learn. There hasn’t been a nest on that spot in the twenty years since.
“More likely the parents brains could only accommodate the idea that they needed to stuff the squawking things in the nest. What are those squawking on the ground? Meaningless noise.”
I doubt that. Parents continue to feed fledged nestlings for several days after they leave the nest. And I doubt if any unattended baby birds on the ground would last long enough in any environment to starve to death, given the number of predators that would find them scrumptious.
I didn’t know that there were four until I found their lifeless bodies on the ground, fat, nearly fledged but cheated of their chance. The only interested predators were the ants.
So much of animal behaviour is like a dance with nature where complex moves depend on a series of triggers or proximate causes. If the parents luck had gone better then they would have witnessed their babies fledge and then seen them leave the nest and then seen where they were. Instead, when something out of step happened, the music stopped and the parents couldn’t respond.
Just to be clear–that’s just your hypothesis, right? Or do you have data? (And I don’t mean general data about animal behavior, I mean specific data on passerine birds with altricial young.)
And I don’t mean to sound confrontational–I’m actually curious to know.
Reblogged this on Mark Solock Blog.
I’m no expert on bird nesting habits, but I find it hard to understand why the birds would choose to build their way out of the wind. Surely they’d just find somewhere not windy? I just have this picture in my mind of Mrs Robin saying, “Darling, it’s perfect, but so windy!” And Mr Robin saying, “Don’t worry about that, my dear, we’ll just build a very high nest! ” “Oh darling, you’re so clever, you think of everything! That’s why I love you so!”
We have a spot outside our back door where we hang flower baskets. Though the baskets change and some are wildly unsuitable, there’s a mama morning dove that tries to nest in the same location (regardless of pot type or rain coverage) every year.
I’m just speculating but its possible that these birds have some territoriality associated with their nesting instinct, and won’t move their “spot” unless something forces them to do so.
Perhaps they were trying to get farther away from the nosy humans gawking at them from below.
The question to start with is, IMO, what cues nest building behavior in the first place?
I’ve never seen anything like this. But I have seen multiple robin nests built when multiple, virtually identical locations were available, e.g. between posts on a fence or on steps of one ladder.
On the bridge, the birds finally started laying in one nest and ended up incubating a piece of gravel kicked up by traffic, as well as blue eggs. The nest site appeared up high to birds flying up from the stream, but was very low compared to the road surface. The nest ultimately failed.
Wild guess.
Robin has nest building instinct. There is abundant building material available, so robin just builds away, until it’s time to nest.
Robins in my backyard built very large nest, so I’m just extrapolating…
Most nests are in trees, and must endure much wind. So, another guess is the tall nest is an attempt to get farther away from perceived threats, i.e. humans.
I think that’s a good theory. Robins are known to build multiple nests in some situations.
The fact that these nests are stacked is a variation on that theme, but still explainable by it.
Here’s an interesting Q&A on robin nesting that backs up your theory:
http://www.learner.org/jnorth/tm/robin/FAQNestsEggs.html
In particular see the answer to the question “Is it common for a robin to build more than one nest at a time?” and the answer 4) to the question: “My robin built a nest and then disappeared before laying eggs. What happened?”
PS
The more secluded the nest, such as up in the corner, with a smaller entrance makes the birds feel more secure. Also, the highly placed upper nest obscures the birds from being seen. Again, a security measure.
Maybe the dad wanted space for a “man-cave” in the basement. Or maybe they want to rent out the lower levels and make it an “income property.” Either way, I’ve been watching way too much HGTV.
It probably doesn’t work in this case, but a common reason for birds to build a nest on top of another nest is that cowbirds have laid eggs in the first nest, and new construction is a way — a bizarre, labor-intensive, but effective way — to avoid nest parasitism.
That was my first thought too — but it does sound like that’s probably ruled out. I wonder though if attacks by cowbirds could have been missed by the people but noticed by the robins.
I think it’s just an errant genetic thing: this particular robin’s nest-building instinct has gone into “overdrive”: if it were advantageous, you’d see this behavior spread through the population. It probably won’t be, of course, because of the increased time and labor involved.
They’re sinner-type birds, and this is their equivalent of the Tower of Babel. The Lord is gonna smite them, sure as can be, so I’d move the barbeque grill and the Adirondack chairs if I were you.
Robins tend to build large, sturdy nests that often include a layer of mud. The nests I’ve seen in bushes were bulky and sprawling. My theory on the tall nest is that the birds were attracted to the sheltered location but there was nowhere to build but up, so the extra layers added the appropriate weight and bulk.
Now I have the theme song from The Jefferson’s in my head 😉
I got to squee and run around the house showing everybody this.
I don’t really see how taller gets them out of the wind. I think the overdrive theory makes sense. It took a long time to warm up here and they might’ve felt some desperation to get a nest built and lay their eggs when it did warm up.
Robins actually build multiple nests fairly often. They have high rates of nest predation and parasitism and thus regularly re-nest (unlike, for example, chickadees, which are cavity nesters and re-nest less frequently). The wind avoidance idea is possible, but would not be my first choice. The robins nesting in my area don’t seem to care too much about the wind. My guess is some form of nest parasite, probably an invertebrate, or brood parasite like a cowbird. It could also be that the nest was getting wet at the bottom, so the female kept building until the nest stayed dry. Whatever the reason, it’s a cool find.