6 May 2025

When I stopped by Duck Hollow early this week I was amazed to see so few mallards and all of them male when only a month ago I saw many more ducks and both sexes. The difference now is that female mallards are on eggs. The males have nothing to do. They never incubate and they don’t help raise the kids.

Last month each female mallard chose a nest site under overhanging vegetation, typically on the ground and typically near water, where she laid a clutch of 1-13 eggs. She incubates the eggs for about 28 days and when she reappears she’ll have ducklings in tow. At night she will brood them until they’re two weeks old.

Urban mallards behave differently than wild mallards. Here are some interesting facts, paraphrased from Birds of the World:

• Experimental evidence has shown that mallards may be able to assess mammalian predator risk by detecting the animals’ urine at potential nest sites.
• Urban mallards sometimes nest on woodpiles, on buildings, and on artificial structures such as docks and boats. Not the female in a planter shown above.
• Unlike wild mallards, urban mallards will re-nest if the first clutch is destroyed or if all chicks are lost to predation. They even raise second broods if they are in unnaturally crowded populations. (*So this is a puzzle: They are overcrowded yet they raise a second brood anyway. Why?)
• It is rare for a female to abandon her nest during incubation but is common under crowding and in urban populations. (Crowding makes them crazy?)

In the coming weeks mallard eggs will hatch and families will appear on the water. Watch for scenes like this at the end of May.