Robin Nests and Eggs
Contributed by Ornithologist Laura Erickson
American Robin Characteristics
L. Birnbaum
  • Rita: we're missing the obvious questions:
  • how big is a nest (size, weight, materials)
  • what is a nest made of
  • how long does it take to build (building process)
  • who builds the nest (male and female roles)
  • does a robin reuse its nest (reuse)
  • where does it build the nest (location)

Q. Is it OK to move a robin's nest?
There has been a nest in our yard, and the babies and nest have been constantly falling out of the tree. Will the parents be able to find the babies or should we move the nest back where we found it?

A. Is this a robin nest? They tend to fall apart when they fall out of a tree, because the mud crumbles, and so the nest would be difficult to replace. Of course, other nests aren't easy to replace, either. Normally when there are tiny nestlings and a fallen nest, we try to get it back in place by putting it in something like a blueberry basket, and then place that basket sturdily in the tree's branches. This is a good website to bookmark for times when you need assistance for birds in trouble: Unfortunately, sending an email to any website can't help in an immediate crisis.

Q. After the baby robins leave the nest, should I leave it for her to use again, or take it down?
A. While robins might repair or build on top of a previous nest, most of them build a new nest. This is best for many reasons. A used nest is a mess, stretched out and often home to insects or parasites and possibly poop. Take the nest down and the nest site will be ready for the next robin family.

Q. Can I move and relocate a robin's nest?
We recently discovered that a robin built a nest in my daughter's swingset. My husband looked a couple days ago and there was one egg in the nest. He removed the slide and the steps so that children will stay away, but the problem is we are moving in three weeks and the swingset will have to be dismantled and moved with us. According to what I've learned by reading some of your information, the egg(s) will hatch by this time but it will still be too early for the baby birds to be out of the nest.
Unfortunately, no. If you move a robin's nest the parents will most likely abandon the nest, eggs, and young. Nest-site fidelity grows during the nesting season. The more time and energy the birds invest in the nest, the less likely they are to abandon it when disturbed. However, actually moving the nest is not merely a disturbance—it makes the entire nest environment different.

Do the birds know to abandon a nest that appears to have been discovered by a predator or do the birds think it's a completely different nest? As the mother builds, she is memorizing all the features around the nest. When those features are gone, she may simply not even recognize her nest anymore.I took care of four baby Blue Jay nestlings, well feathered, after their nest and its branches were knocked out of a tree in a storm. The people who found it all recovered the nest and put it in another near-by tree, but even with the babies calling, they simply didn't figure it out, and they'd invested a lot of time and energy into these babies already.

The birds' fidelity is to the whole nest setting. Interestingly, there is a documented case of a robin that raised babies on the structure of a crane that was operational during the time she built, incubated, and raised her babies in it. Another case of a robin that nested in a train car, and followed it when it moved from place to place. I can't find an instance of a robin staying with her nest when the nest was put on another structure.

So, I don't know what to tell you about moving your swingset. It would have been far better to take the nest apart as soon as you noticed her so she could simply build a new nest elsewhere and not lose well developed eggs or babies when the nest would be moved later, since they knew they would be moving. I's too late for that now, but I hope reading this may be helpful to others in the future.

This is still my best advice; Look for support of what scientists know about nest site fidelity, as well as how individual robins are smart enough to observe and learn—even to discover that nice people look out for ways to help robins:

Last summer a tree was chopped down across the street and a family of baby robins was left homeless. I took the nest and moved it across the street to my front porch and the daddy robin seemed to have no trouble finding his little ones. We got to watch three little fledglings grow up and had the honor of watching the last one fly away. I don't know if that is normal behavior but I wanted to let you know that it is possible.

I must be very lucky...I have moved several American Robin nests. I use to live in a home where my front porch was open and I had old plastic roll up blinds around the openings. As Spring started I left on a trip and when I returned the robins had a nest with eggs hatched on the end of the rolled up blind. This was on the West side so I needed the use of the blind. I moved the nest about 2 feet to the left of the blind and put it on the flat pipe of a metal down spout, plus I fastened it to the spout with duct tape! Not only did the robins stay and raise the babies, they came back 4 years in a row and did the exact same thing and each year I moved the nest and each year the robins never objected. The nests were completely protected under the porch roof on top of that down spout. I was so fortunate to move the nest successfully! This was in Cincinnati, Ohio in about the months, each year, of mid April to mid May each year.

Q. Will the male robin take over the nest if the mother cannot? A cat killed one of my nesting robins and she was sitting on four eggs.
A. How very sad. If the female was killed, the eggs are doomed. The male doesn't have a brood patch and doesn't know how to brood eggs. If it was the male who died, the female might continue to incubate, but may just give the nest up for lost because the chances of bringing off more than one or two nestlings is very slight with just her to feed them. Also, the female starts focusing on a new batch of eggs after the young fledge, so the father is quite essential for the 'finishing school' lessons on surviving. Outdoor cats are a serious ecological problem, but also cause such heartbreaking individual losses. I'm very sorry. That said, please do write to let us know if one of the parents attends the nest, and what happens, as this is best way for scientists to keep on learning about robins and their individual differences.

Q. Is it common for a robin to build more than one nest at a time? We have a pair of robins nesting under our deck on the support beam. We have been watching the female fly off to collect nesting material. She has built 2 nests within 5 feet of each other. At first, I thought she started one and abandoned it, but she actually worked on both and were almost finished in 2 days!
A. This is a question we hadn't been asked before, so we wrote to Len Eiserer, the author of The American Robin: A Backyard Institution. Len answered,

Building multiple nests simultaneously happens every now and again with robins. One started 26 different nests on roof rafters of a garage under construction; another built 8 on successive steps of a fire escape. Support from underneath is the primary site selection factor for the female robin — it's more important than concealment. Because some human structures provide repetitive sites with strong support, the female can get seduced into building multiple nests.

This is an example of "supernormal stimuli" — artificial stimuli that are even more effective than those provided by Mother Nature (tree limbs). Animals have a hard time resisting supernormal stimuli. There are many examples. Your robin will probably settle on one site and just lay eggs in that nest, or else just incubate eggs in that nest after laying, say, one egg in one nest and two in the other. She won't lay two complete sets of eggs and try to incubate both of them at the same time.

Q. Will a blue jay steal eggs from a robin's nest? We have been watching two nests in our yard. Yesterday I found an egg on the ground away from the nest in a different part of the yard. I checked one of the nests and all four eggs were gone. I'm thinking blue jays may have robbed the robin's nest.
A. The main predators of robin eggs are snakes, squirrels, blue jays, and crows. Deer eat a lot of bird eggs and nestlings, too, but only from ground nests. Snakes swallow eggs on the spot, and since you found one egg in the yard, a snake most certainly wasn't the culprit. Squirrels usually stay up in branches, and seldom drop their eggs, so I'm betting it wasn't a squirrel, either. Jays and crows are both egg and nestling eaters, and so it's hard to be sure which species raided your nest. Robins actually appreciate having jays around as long as they stay away from their nests, because jays are good at warning about other dangers. But it's heartbreaking to lose the eggs or nestlings of any nest to predators. And the worst problem with crows and jays is that both species are highly intelligent. If you are studying the nests in your yard, be sure that there are no crows or jays watching you. If they figure out that you're watching nests, they may start watching for you to lead them to their next supper.

Q. What can we do with the robin egg we found in our yard?
A. The best thing to do with an egg that you find is to simply leave it be. I know you're concerned about the little baby growing in it, but there is a strong chance that there may not even be a baby in there. This may be an egg that wasn't fertilized, or didn't develop properly. After the other babies are a day or two old, the parents get rid of unhatched eggs just in case one of the growing babies accidentally crushes it. Rotten eggs are no fun!

There is also a chance that there really was a healthy baby inside the egg. One likely case: a predator may have carried off the egg, and dropped it in a panic as the angry parents dive-bombed it. Although the egg looks fine on the outside, the baby inside may have been badly shaken during the flight and especially when it was dropped. If so, the baby inside may already be dead or may soon die, and if it does survive to hatch, there is a strong possibility that it will be badly deformed, making its short life unendurably painful.

Even if the egg were perfectly healthy, the chance of a human successfully incubating the egg and then successfully raising the baby from a hatchling is VERY remote. Robin eggs require high humidity, gentle daily turning, and level heat. You'd need a high-quality incubator to do it properly. Then once the babies hatch, parent robins feed them regurgitated worms and insects for the first three or four days--something humans just can't do!. Newly hatched robins are weak and helpless, and their parents are designed precisely and have the exact right instincts for taking care of them. Our human hands are clumsy, and we have too many other concerns in our daily lives to devote every waking moment to a baby robin, as its real parents would do naturally.

People tend to both under- AND over-estimate the amount of food baby robins need, giving them too much in single feedings and not enough over an entire day. The real parents spend literally every waking hour searching for food for them, returning to the nest every few minutes all day long, from sunrise to sunset. Can you do this consistently for several weeks? It's also very difficult to make a baby bird diet exactly balanced. Robins feed their young worms, insects, spiders, and some fruits. Outdoors, the nest is shaded enough to protect from sun but gets a few rays of sun each day, which the baby requires for manufacturing Vitamin D-3. Indoors, you need to provide this vitamin, but it's very difficult to make the precise balance of calories and vitamins and minerals that natural robin parents provide.

There are very good reasons why it is against state and federal laws in the US to raise wild baby birds. Death at the hands of well-meaning people who aren't feeding a robin nestling the proper diet can be painful for the baby. Far, far better to just allow the egg to cool. If a baby is still alive in there, it will simply stop developing within the egg, before it develops any awareness of pain.

Q. Should we try to raise abandoned eggs ourselves? A robin nest on our eaves has seven eggs in it, and suddenly the robins are gone! We haven't seen the mother in 4 days!
A. Ornithologists call robins determinate layers. After a female robin lays four or five eggs, her body simply stops producing more until she's incubated and raised these. So seven eggs is too many for one robin to have laid. There must have been another bird laying her eggs in there besides the pair. That may be why it was abandoned. Robins only abandon their eggs when something happens that tells the robins they will have a poor chance of success. It seems unlikely that humans will have greater success. I know how sad it is to see these beautiful eggs and how very tempting it is to want to save the tiny babies inside. But it's just as heartbreaking to watch the babies start out healthy, with their egg sac to provide some nutrition for a couple of days, and then wither and die at our hands.

Q. My robin built a nest and then disappeared before laying eggs. What happened? A robin built her nest in our pear tree in the side yard and just finished it about two days ago, I have not seen her lately. Do they stay away while waiting to lay the eggs? I am hoping she has not been hurt or killed but I have not seen the male around lately either.
A. Here are some possibilities to explain why the robins have not come back to use the nest:

1) Something dire happened to one or both robins: hit by a car, taken by a predator, etc.

2) She laid an egg but then something came and got the egg, and she quit laying.

3) She discovered a potential predator, such as a cat, jay, chipmunk, or snake, eyeing her nest and abandoned it because it wasn't a safe place to raise babies.

4) She built her nest more quickly than expected (perhaps there was a a good supply of mud from a recent rain?) and she wasn't quite ready to start laying eggs.

We would suggest that you give her just a few days to make sure it wasn't just an ovulation thing and she was indeed dallying until she was ready to start laying eggs. If she does not return after 2-4 days, go ahead and remove the nest. Any other robins that come will build their own nest.

Q. Did I harm the eggs in a robin's nest hidden in my hanging plant by accidentally pouring warm water over them?  Before I knew the eggs were there (the plant is higher than I can see inside) I watered it with warm water, surely pouring water directly over at least one of the eggs. The mother is still sitting on the nest. What's the chance that I've already harmed the eggs?
A. Anything that is outdoors has to be at least a little waterproof. If the eggs weren’t sitting in water for longer than a few minutes, the ones that got wet should be fine.

Q. Should I just quit watering it and let the plant die? While the nest is in the middle of the full plant, and technically I could water around the edges, I'm afraid I will harm the eggs and baby birds when they hatch.  I don't mind losing the plant but it's nice cover and protects the nest.  By my calculations the eggs have been in the nest at least four days.
A. It should be fine to water around the edge, but give the mother time to fly off each time, and don’t water after the babies’ feathers are growing thick and they get close to fledging.

Q. How do we know if the bird inside a found robin egg is thriving? My daughter found an intact Robin egg in the grass. There was no nest anywhere. We took it home wondering if the bird was still alive in its egg. we are currently trying to keep it by putting it in an abandoned nest under warm light.
A. You are going to be for serious heartbreak. If a robin egg is on the ground like this, it was either infertile and dumped by the parents, and won't hatch—or was carried off by a jay or crow, and the robin parents chased them and forced the thief to drop the egg. The shaking and dropping could have badly damaged the embryo, and if the egg did hatch, the baby would not be likely to survive long.

Even if the egg were healthy, most of us just don't see all the work that goes into incubation. the right temperature is important, but so is humidity, and so is frequent turning to ensure that no part of the growing chick gets dried out or stuck to the shell. Then if it doe survive to hatch, keeping this tiny chick alive is very, very difficult to do successfully, even by a trained wildlife rehabilitator. These are some of the reasons it is against state and federal laws to keep any wild bird egg or chick.

Q. How long does it usually take a robin to build a nest? Are robins sometimes inept at nest building? I have a robin who started a nest in my front porch light. It appears there is some dirt or mud in the shade and the raffia-type grasses hanging loose and stingy, with no structure, all around the outside of the shade. During the day I'll see the robin sitting on top of it or flying back and forth from it, but the nesting materials a rent' taking any shape. I'm wondering if the robin is actually considering the shade itself to be the nest, rather than building herself a normal nest, or if this is just a long process and the nest is still incomplete. She appears to be sitting on the light bulb when she's in the "nest." Is this normal behavior, or do I have a robin who just isn't too bright?
A. It takes two to six days for robins to build their nest. This robin sounds inexperienced. If this is not an appropriate place for her to nest, the quicker she figures it out the better. Sometimes tenacity if important, but this bird is wasting time and energy. The male may be frustrated that she is kind of stupid, or he may be be inexperienced too. There are usually more males in an area than females to this should not be a female without a mate.

Q. Would she be living someplace separate from the nest she is building? I don't see the robin in the "nest" in the evening. There weren't any eggs in there when I checked a couple weeks ago.
A. Remember that the nest is not a bed; it's an incubator and baby cradle, so the robin isn't supposed to be on the nest at night until she has a full clutch of eggs. Until then, she roosts on a branch.