Hi. You want to use the words incubation period for eggs. Gestation refers to animals that give live birth. The Incubation period for an American Robin is 12-13 days, it can be longer if the hen is absent from the nest due to being disturbed. It might hatch in as few a nine days or so if the egg received constant optimum heat.
It seems the answer is: It varies, from 3 to 4 weeks or so. Here is an interesting discussion i found on the topic:
I have a robin's next on my downspout under the eaves of the house. This is the second robin/nest this year. The first eggs hatched and both robins were tag-team feeding them. About 2 days later they were gone. Don't know what happened. I have another robin that has been sitting on the eggs for 35+ days. I have read different things about robin gestation. I am wondering if they should have hatched by now. The robin is sitting on the nest almost all the time. Could the eggs be "duds"? Shouldn't the robin know?
Thanks
ANSWER: The eggs could indeed be sterile, or not viable for some reason or another. They may not hatch, the parents will continue to incubate them until they lose interest and move on if this is the case.
OR
The parents may have delayed beginning the incubation period until they felt they had enough eggs in their clutch. The eggs can survive for quite a few days without any attention at all from the parents. The parents can literally choose when to begin incubation so the 35 days may not have been true incubation days... If you can easily see how many eggs are in the nest you can do a rough estimate of hatching if you are sure when the first egg was laid...
For example, some birds lay an egg a day and the last egg laid will "sometimes" be the day the incubation period started. This is more common for the first clutch of eggs for new parents...
Old hands may lay one egg every second or even third day and then wait for another couple days to begin incubation. So if you have 5 eggs in the nest and we assume this is an "old hands" nest the incubation may not have begun for 10 - 12+ days AFTER the first egg appeared. 40 days would not be unreasonable in that circumstance.
There are many factors that can affect the success of the clutch, summertime heat or cold spells kill developing chicks every day. This is why nature allows for several nestings every year.
I can not really say how long a Robin will sit on dead eggs, but I am going to wager a guess that when the egg dries up inside and becomes brittle, the Robin will be able to tell and will move on with it's life. It may build another nest or it may kick out those eggs and lay new eggs if it is quite fond of that site...
I am curious what will happen with this nest myself... If you figure out what is going on, if chicks appear or if the nest is abandoned, drop me a note if you think about it and give me an update...
Answers & Comments
Verified answer
Hi. You want to use the words incubation period for eggs. Gestation refers to animals that give live birth. The Incubation period for an American Robin is 12-13 days, it can be longer if the hen is absent from the nest due to being disturbed. It might hatch in as few a nine days or so if the egg received constant optimum heat.
It seems the answer is: It varies, from 3 to 4 weeks or so. Here is an interesting discussion i found on the topic:
I have a robin's next on my downspout under the eaves of the house. This is the second robin/nest this year. The first eggs hatched and both robins were tag-team feeding them. About 2 days later they were gone. Don't know what happened. I have another robin that has been sitting on the eggs for 35+ days. I have read different things about robin gestation. I am wondering if they should have hatched by now. The robin is sitting on the nest almost all the time. Could the eggs be "duds"? Shouldn't the robin know?
Thanks
ANSWER: The eggs could indeed be sterile, or not viable for some reason or another. They may not hatch, the parents will continue to incubate them until they lose interest and move on if this is the case.
OR
The parents may have delayed beginning the incubation period until they felt they had enough eggs in their clutch. The eggs can survive for quite a few days without any attention at all from the parents. The parents can literally choose when to begin incubation so the 35 days may not have been true incubation days... If you can easily see how many eggs are in the nest you can do a rough estimate of hatching if you are sure when the first egg was laid...
For example, some birds lay an egg a day and the last egg laid will "sometimes" be the day the incubation period started. This is more common for the first clutch of eggs for new parents...
Old hands may lay one egg every second or even third day and then wait for another couple days to begin incubation. So if you have 5 eggs in the nest and we assume this is an "old hands" nest the incubation may not have begun for 10 - 12+ days AFTER the first egg appeared. 40 days would not be unreasonable in that circumstance.
There are many factors that can affect the success of the clutch, summertime heat or cold spells kill developing chicks every day. This is why nature allows for several nestings every year.
I can not really say how long a Robin will sit on dead eggs, but I am going to wager a guess that when the egg dries up inside and becomes brittle, the Robin will be able to tell and will move on with it's life. It may build another nest or it may kick out those eggs and lay new eggs if it is quite fond of that site...
I am curious what will happen with this nest myself... If you figure out what is going on, if chicks appear or if the nest is abandoned, drop me a note if you think about it and give me an update...
Thank you and best wishes.
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RE:
what is gestation period of a robin egg?
American Robin Egg
12-14 days for the American Robin.