Why a Female Duck Was Spotted with a Huge Brood of 76 Ducklings
Think of it as ducky day care
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Make way for ducklings—a whopping 76 of them.
Hobby wildlife photographer Brent Cizek recently captured an incredible scene on Minnesota’s Lake Bemidji: a single female common merganser duck, trailed by about six-dozen fluffy ducklings. As Sarah Mervosh reports for the New York Times, the hen, which Cizek has dubbed “Mama Merganser,” is not the mother of all the ducklings. Instead, she appears to be the head of a ducky day care.
Cizek photographed the ducks last month. In an interview with Jilliam Mock of the Audubon Society, he says that he wasn’t expecting to see anything particularly exciting out on the glacially formed lake that day—perhaps just a mallard he had spotted earlier—and had brought only one lens with him on his small plastic boat. Weather conditions were also less than optimal: a storm was brewing, and the waters were choppy.
Then Cizek saw the female common merganser with a huge brood of ducklings in tow. At the time, he estimated that there were at least 50 babies paddling in the water; during a second trip to the lake, he counted 76.
“I probably shot 50 pictures, and I was just praying that one was going to turn out sharp because the waves were so strong it was nearly impossible to even keep them in the frame,” Cizek tells Mock. “Luckily enough, just one picture turned out.”
Female common mergansers only lay about 12 eggs at a time, so it’s safe to say that not all of the babies are the offspring of Mama Merganser. In fact, female ducks have been known to travel with a few extra babies in tow. Ducks often lay their eggs in the nests of other ducks—sometimes, they will even deposit eggs with different duck species. Kenn Kaufman, the field editor for Audubon, tells Mock that this behavior is somewhat puzzling to scientists, but it is possible that the ducks are trying to increase their babies’ odds of survival by spreading them across different nests.
“One possibility would be, in a sense, not putting all their eggs in one basket,” as Kaufman says.
This does not, however, fully explain the scene at Lake Bemidji, since Mama Merganser would not have been able to successfully incubate more than 20 eggs. So where did the rest of the babies come from?
Cizek seems to have stumbled upon a crèche, the term used to describe a “daycare system” where some species of baby birds separate from their parents and form a group supervised by a few adults. Bob Duchesne, who writes a regular birding column for the Bangor Daily News, explains that crèche behavior “is unusual but not rare. It is most typical among birds that breed colonially and whose eggs hatch at roughly the same time.”
“Crèching” lets baby birds meld into a big crowd, which can in turn increase their chances of survival. Sometimes, birds form crèches before they are able to feed themselves, in which case delegating babysitting duties to a few adults gives parents the opportunity to forage for food. Among some bird species, non-breeding adults are responsible for looking after the babies, but in other species, dominant pairs will compete for the chance to bring new offspring into their group.
David Rave, an area wildlife manager with the Minnesota Department of Natural Resources, tells Mervosh of the Times that Mama Merganser is likely a matriarchal female with previous experience rearing ducklings. He has seen merganser crèches of up to 50 ducklings, but says that with more than 70 babies following her sticking closely to her side, Mama Merganser has taken an unusually large brood under her wing.