Confused Waterfowl
Male ducks are notorious for attempting to mate with other species — researchers have documented them trying with over 40 different bird species and even other animals.
Male ducks are among the most indiscriminate maters in the bird world. They've been documented attempting copulation with an astonishing variety of other species — and some non-birds.
Observed interspecies mating attempts include: - Other duck species (very common) - Geese - Swans - Chickens - Even dead ducks (leading to a famous scientific paper on "homosexual necrophilia in the mallard")
Why are male ducks so... enthusiastic?
Several factors contribute: 1. High sex drive — Male ducks have extremely high testosterone during breeding season 2. Forced copulation — Duck mating often involves males pursuing resistant females, so males are "programmed" to persist despite rejection 3. Similar cues — Many waterfowl share similar body plans 4. Opportunity — Mixed-species flocks are common in wetlands
The result of all this interspecies mating? Hybrid ducks are extremely common. Unlike many animal groups, duck hybrids are often fertile and can produce their own offspring.
This creates a "species problem" for ornithologists. Where does one species end and another begin when they're constantly hybridizing? Some researchers estimate that 5-10% of wild ducks may be hybrids.
The female duck's complex corkscrew reproductive tract (which we covered in another fact) may have evolved partly in response to this pressure — giving females more control over which sperm actually fertilizes their eggs.