Hey trapperman brothers, In the past I have posted some posts and pictures of my wood duck nesting box line I have right behind my cabin. This year started out looking like it was going to be a great one. I had wood ducks everywhere up and down the creek. As usual I had a box that must of been a "dump box" for a couple or more hens. Some told me this is because I have too many boxes up too close to each other. Some said not enough boxes up in an area. I have always had a dump box in my group of boxes here for the last 5 years. A hen always hatched almost all the eggs, Sometimes 26 or 28 duckies. But this year on a dump box on day I noticed a bunch of wood chips all over the ground with nest down everywhere on the ground. I left it alone. Now today I checked a few boxes and 2 have a bunch of eggs but no hen sitting on them. They are abandoned. I have 3 boxes along the creek that have hens setting. I wonder if an owl or some bird of prey got the hens and got in the box to mess it up. The boxes are 8 foot high on a steel pipe. Right on the creek bank. Would an owl get in the boxes if small enough ? I'll go check all my boxes 2morrow. I have 12 or 13 up , some in other places miles away. Comments ??

we've caught snakes and wood rats on camera getting in ours

Hard to know what your spacing or density of nests is, but I too have heard waterfowl managers discuss too many boxes in a small area encouraging nest dumping and maybe after 5 years of having high density it caught up with you. Also if you have higher density of boxes then you are creating a more attractive site for predators as well.

Bryce

I have had bea box up for 5 years and it is always used as a dump box. I have moved it to a more secluded area this year. Maybe they will hatch eggs in it this year.

Since they hatch all of the eggs in the dump nest, not too big of a problem???

Seems you are on the right track since Cornell University lists "abundance and conspicuousness of artificial nest boxes" as a likely reason for egg dumping. Eliminate those two variables and see what happens.

"Egg-dumping, or "intraspecific brood parasitism" is common in Wood Ducks—females visit other Wood Duck cavities, lay eggs in them, and leave them to be raised by the other female. This may have been made more common by the abundance and conspicuousness of artificial nest boxes; in some areas it happens in more than half of all nests. Individual females typically lay 10-11 eggs per clutch, but some very full nests have been found containing 29 eggs, the result of egg-dumping."

https://www.allaboutbirds.org/guide/Wood_Duck/lifehistory

Sure they're abandoned? Eggs can sit in the nest without a hen for weeks and still be viable. However once she starts sitting, she has to stick with it.

Wood chips, etc sounds like a woodpecker taking over.

Love wood ducks! Hoping for the best with your endeavor

They only start to rear the eggs when the clutch is full and down usually only comes out 2 days before that. Size of the nest bowl also reduces the laying egg numbers.
Consider a Peleated wood pecker size of cavity as their natural size for nesting and clutches in these average 7=8 eggs for wood ducks.

Always look for tail markings at the entrances and their sizes and that indicates what is coming. If a rainy day the starlings leave their tail signature because they feed on the ground.

Out of curiosity, what are the dimensions of your boxes?

Thanks for all the comments. Interesting and much to learn. My boxes are made from a couple different size boards. My old boxes were made using 1 X 12s and now I make boxes using 1 X 10s. The side are 22" long and the entrance hole is about a 3 X 4 inch oval. Probably down about 4 inches from the top. I don't think the way the boxes are made is a big problem.

You don’t want perches on the outside. Kerf cuts on the outside can serve the same purpose as perches.


Wood ducks don’t need it, but predators sure do. It allows easier access for predators as it gives them a way to get a grip while at the entrance.

Too many boxes out, you’ll end up losing more ducks than gaining.
Make sure your poles have a predator guard.
Make sure you have some sort of screen inside so the ducklings can exit the box.
And remember wood ducks aren’t the only cavity nesting ducks around. Mergansers, Goldeneyes, and Buffleheads are all cavity nesters. Down here it not uncommon to see different ducklings with different hens.
And remember, less is more with boxes.

The depth of the hole is important because the racoons can sit on top and wave their arms around till the female is reached. They can learn to climb 2 inch pipe.

Another way to prevent coons from reaching in to the eggs is by NOT putting too many wood ships, sawdust, whatever in the box. Clean them out every year and put a new layer of a couple inches of nesting material in the very bottom of the box. The hen will add whatever she wants including down, etc.

I agree with Wannabe that screen, maybe 1/4 or 1/2 inch mesh inside the box will make it possible for the ducklings to climb out when it's time.

Moosetrot

Went and checked a box by itself...… no other nests near it within a quarter mile. When I walked up to it a Woodie hen flew off. Took a picture of the inside box. Mamma is doing triple duty as I counted 27.... maybe a couple more....eggs. Will any or maybe all hatch? I'll check it again in a month to see the results.

It's to bad that its illegal to take the extra eggs out, incubate them, hatch the ducklings, grow them out and release them. A state could dramatically increase the number of woodducks if they did this in a few wetlands. Most ducklings die in the wild. Raised in captivity, most would live to breeding age.

Pulling all the eggs, except for a few dummy eggs to encourage more laying and rearing the ducklings would result in an enormous amount of ducklings, probably dozens of times what the woodducks would rear on their own.

Predation issues on the released adults may be worse.

Keith

You have some mergansers there, seems 2 middle eggs sure looks like theirs.
Mb Coonguy's mother did a book on "Day old downy waterfowl of the world", a 25 year project of hers.

Excellent point KeithC.

No worries NCM. Yes, she can hatch and rear that whole clutch.

I'll never understand a dump nest. We have 100 or so boxes. Not many dump nests, but a few. We have a pole that has a cluster of 3 boxes on it, side by side and no dumping. While hooded mergansers will use boxes, I don't see their eggs in your picture. Something you may not know is the wood duck will lay a second clutch after raising her first brood, only duck that does.

Hooded Merganser eggs are1.7 "-2.4" and are white , nearly sphericial ; where as Woody's are 1.4 " -1.6" colour of white and glossy cream

Hoodies are well know to be parasitic egg layers much like Redheads are to the scaup family of ducks.