Last year I tried incubating duck eggs twice, and my yields were extremely low. I found that most of the eggs grew to maturity, but never hatched. I concluded that the most likely cause of last year’s poor result was that I incubated in late spring and early summer, when outdoor temperatures were fluctuating wildly. Though I had the incubator in the house, the type of incubator I have is not thermostatically controlled (as far as I can tell)- it’s just controlled by a variable resistor, which you set at the beginning of the incubation period. As the house temperature rose and fell with the weather, I constantly struggled to keep the inside temperature of the incubator correct. So, this year I decided to incubate earlier in the year, when our house temperature remains more stable.
I also theorized that washing the eggs prior to incubation may have been detrimental. Large hatcheries do wash, to cut down on the risk of bacterial contamination on the egg surfaces. But, I figured I’d try mother nature’s approach this time instead. The eggs are naturally coated with a substance that prevents moisture loss, so it’s possible that it’s better to leave that on, despite the added risk of bacteria load. In the photo, you can see how dirty the eggs were. I use an egg-turning device, but this photo was taken after I removed that: the last three days before hatching, you stop turning the eggs so the ducklings can get into position for hatching.
Despite my new attempts, things still didn’t go well! I started out with about 40 eggs, withheld maybe six that didn’t appear fertile at the first candling. But I was expecting a good thirty ducklings out of this batch. What I got: five! A few hatched normally on their own on the due date or one day later. But then, nothing.
Hopefully this doesn’t sound too mad-scientist, but I cracked a few of them open by the third day of lateness, just to evaluate what was going on. Here is an interesting photo of a duckling in his shell, showing how folded-up they are- his foot is on top of his head! His neck and head are completely torqued around, parallel to his body.
In the upper right of the photo is his bill, and above that is where the air sac area of the egg was. So when they are ready to hatch, a small point on the end of the bill penetrates the membrane of the air cell, they starts to “pip” through the egg shell here. Then the baby will work his bill around the circumference of the shell and essentially crack open a “lid” and exit out of that “hatch” in the top of the egg shell. It’s amazing to think they can do all that maneuvering when they are this cramped in there!
What I found when I cracked these open was still-alive ducklings that had not yet completely absorbed their yolks into their abdomens. So, they were developmentally delayed. I believe this is most likely due to the incubation temperature being too low (though you can see I am using THREE thermometers in there for comparison- and all of them read a little different!).
Interestingly, one of these crack-opens survived just fine, what was left of his external yolk just dried up and scabbed over. But, the other ones, though they were wriggly and peeping for the first few minutes out of their shell, perished soon after.
So I gave the rest of the eggs more time, and one actually did hatch out five days late, but did not survive much after hatching. This seems to confirm what the books say: if they don’t hatch on time, within about 48 hours of when they’re due, forget about it. Just discard them, because whatever is left are weak and malformed birds. And hatch time can be hereditary, so you don’t want to keep and breed birds that don’t hatch on time.
I also wonder if ducks aren’t harder to hatch than chickens? Their eggshells are much, much tougher; so I imagine if the hatchling is weakened at all, he just won’t make it out. And, the tiny point on the end of the duck bill meant for cracking the egg is indeed a very tiny point. Where chicken chicks are blessed with an entire pointy beak- a much better tool for tapping oneself out of an eggshell.
My other suspicion as to what is going on is humidity problems. The ducks that did hatch had trouble. Their shells stuck to them, their eyes were stuck shut, and they were just generally gummed up. We had to wash some of them with warm water to help them. This is not normal, ideally they crack out of their shells pretty cleanly, and are dry and fluffy in few hours.
So, I’m going to try again. This time, I calibrated my cheap-o thermometers with our digital oven thermometer, and I do think the cheap-os are reading a little high (which explains why the last batch was late). And I purchased a hygrometer, which measures humidity in the air. I came to realize that these little doodads are inexpensive, and can be obtained at any cigar shop, made for cigar humidors. The cigar-style is just the right size and weight for using inside the incubator, and can just stick on the side.
So, I’ve got a batch of 36 eggs in there now, humming along at 99.5° at 55% humidity. I’m crossing my fingers that I’ve got it down now!
8 thoughts on “Duck Incubator Challenges”
I just posted an article about lambs and I came across your blog as I am looking for posts tagged with the word ‘lambs’. I got caught up reading your post about ducks hatching, or not.
I hope your experience helps with the 36 eggs you have there now. I am bookmarking this site and hope you have good news to report in a while.
My post about ewes in the Yorkshire Dales in England giving birth, is here
Just saw lambs being born at a farm in the Yorkshire Dales near us.
I posted it here at
Thanks for the link David, those are beautiful photos of lambs being born! I think baby lambs have an edge over other baby animals, they are pretty darn cute!
I hope your wishes of good luck on eggs help! Sometimes I wonder, “how on earth does the mother manage to pull this off?” when technology can’t seem to do such a good job of it. But I know that natural mothers lose about 30% too, so if I can beat those odds with my machine, eventually, I’ll be happy!
the other variable you can control with hatching eggs is the temperature they’re kept at prior to setting them. The first batch of turkey eggs I set this year had a 45% hatch rate; but the conditions when I ws collecting them were terrible — freezing every night, snow, etc. So by penning my turkeys and collecting the eggs twice a day I was able to eliminate that variable and up my hatch percentage to 95% currently.
Don’t know where the ducks are laying but you should get better hatch rates by collecting the eggs more frequently and storing the prior to set at a stable temperature. For turkeys I like 60 degrees.
That’s good to note. Do you find that the eggs aren’t fertile at all, or aren’t growing at the first candling at 7 days when they are bad like this? Or are you candling at all (as I know you have a LOT more eggs than I do!)? I was pretty good about collecting them each morning right after they were laid, and brought them into the pantry, where it’s maybe 50-60 degrees, and I had them on the egg turner during the week I was collecting. But I may have to make this even more climate-controlled, if other factors aren’t working for me. Who knew it was this complicated what hens do with their little pea brains!!
I stumbled upon your blog while searching for information on what looks like it’s going to be a 0% hatch for my first go at artificially incubating Pekin eggs.
First collection was eight eggs on the day they were laid. I was down to one by the 14th day candling and the one I have left appeared to be doing great, but I candled today (just to see) and it looks like I have a quitter. Lots of visible space in the egg. Hmmm. Hatch is due tomorrow, so I will give it a couple days to make sure my inexperienced eye isn’t just misinterpreting what I’m seeing in there.
I have another set that is on day 15 and appears to be developing on track so far. I think my setup is similar to yours. If you don’t mind, I’m going to follow your progress and see how your current set goes and hopefully pick up some pointers. 🙂
Tiffany hi! I have not tried to make judgments on candling past the 7th day, only because I too feel like I can’t tell what’s going on in there for sure and don’t want to throw away good ones! In our last hatch, there were a couple that looked all black and horrible right before the hatch, I thought for sure they were rotten and ready to explode- but it just turned out to be dark-colored ducks!
I’ve read that if you see a very large air pocket, that could mean that you had too much evaporation of moisture out of the egg. This is turning out to be sooo hard, I just can’t imagine how the real duck mothers have such good luck with all the variabilty of nature!
I’ll have to write a post on the results of my most recent attempt- seven babies out of 36 eggs incubated. It’s a small improvement over our other attempts, but still a pretty bad return! :=( I think it must be my incubator design, because I really did everything right this time! I’m going to wait until my chickens start laying, and see if I can do any better with chicken eggs. I think ultimately, the more expensive, professional-style incubator “cabinets” probably work better than the cheapie foam cooler design!
I don’t understand why you removed the ducklings from their shells completely instead of moving ahead cautiously and trying to help them hatch. There is a lot of advice online about how to help ducklings hatch when the membranes have become tough.
Steve- I have found that when the duckling doesn’t hatch normally at the normal time, his odds are not good no matter what you do. I’ve hatched quite a few batches since I wrote this three years ago, and have tinkered with only partially opening their shells- but they are always too weak to make any effort at all to finish the job. And I find once the shell is cracked, if you don’t get the membrane off them while it’s still wet, it dries on them like cement and immobilizes them. So I feel if they aren’t getting the job done on their own, you’ve gotta get in there and help them, and there is risk either way.
Nowadays, I just throw away eggs that don’t hatch about 4 days after the due date. I think if they are late, they are doomed almost not matter what. When I wrote this, I was ready to throw the eggs away anyway, they would have died in their shells without me taking some action, so I decided to open them up to try to learn what was going wrong.
My ultimate conclusion is the foam-cooler-style incubators are garbage, unless you can keep them in a climate-controlled room. They fluctuate too much in temp based on ambient air, and it just messes up most of the eggs.