Most duck hunters realize that ducks generally don’t live a long time. From the occasional leg band, to seeing significant population fluctuations based on nesting conditions, it’s pretty easy to have an anecdote on duck’s lifespans. But, how long do ducks actually live? It’s a common question for Delta Waterfowl’s Dr. Chris Nicolai, and he says that all depends on where you start counting.
If you’re counting eggs, the average lifespan would be mere days.
“Right now, a good nest success average is .15,” Nicolai said. “So out of 100 eggs laid, only 15 ever hatch. In areas that there’s no trapping, nest success can be 0-5%.”
According to Delta Waterfowl, the vast majority of that egg destruction is predation, roughly 90%, and the rest is due to flooding, weather events, etc. That 15% success rate shows just how big an impact that predators have on duck populations, which was discussed on the MeatEater Podcast episode “Rut, The Dating App.”
But, the lifespan doesn’t improve much, even once the eggs hatch, especially in areas that aren’t trapped and the predators aren’t in check.
“From when they hatch to when they can fly, another half of them will die,” Nicolai said. “At best, only 7.5% of eggs fly away from the pond they nested on, at best.”
Only 7.5% of eggs left as real, live ducks after only a few months is rough, but once they get to flying age, their survival rate from year one to year two improves dramatically, compared to eggs and chicks anyway. While these numbers might not be exact on any given year, the survival rate of drake mallards is around 70%, and around 60% in hen mallards.
So, starting with 100 of each, you’re at 70 drakes left and 60 hens after year one. The following year, you go to 49 drakes and 36 hens. Since you’re below 50 now on both, that means half of each are dead, and you’re at an average age of 2 years for a drake, and not even two years for a hen.
And while that’s the case for mallards, this also varies a lot by species, according to Dr. Nicolai. “Are they like mice, or are they like an elephant,” Nicolai said. “A common eider is going to have a better average age than blue wings, because of how they nest and populate. For example, 40% of blue-winged teal live from one year to year two, but a blue wing starts laying eggs at 11 months old and lays 12 eggs. On the contrary, roughly 90% of common eiders live from year one to year two, but they don’t start nesting until they’re 3 or 4 years old, and probably will only lay 6 eggs.”
And even though the odds are stacked against them over and over again, things do tend to get better as ducks age.
“Survival rates increase as the ducks get older,” Nicolai said. “They do better with age, as they build up a library of places that they can find forage and safety. Then you get ‘super hens’ that really know how to produce more kids.”
The result is certain ducks that just survive year after year.
According to the U.S. Geological Survey, these ducks below are the oldest hunter-harvested ducks of each species.
Once they're able to migrate, humans become duck’s main predator. Hunters kill around 10 to 11 million ducks a year. With a continental population estimate of around 45 million, that shows how effectively nesting repopulates the continent's ducks.
What extends their lifespan is building up a library of safe places that provide food and cover. When a duck finds a National Wildlife Refuge that's not open to hunting, they continue to utilize it for extended periods of time.
Adult ducks are incredibly resilient outside of nesting season, so they don't necessarily have a common form of death. Bald Eagles, power lines, and weather events are all mortality events I've personally witnessed. During nesting season, red fox love to target hens on the nest. But, hunters account for the vast majority of adult duck death.