How do platypuses court and mate in the water?

Courtship and mating for the platypus occur in the water from late winter through spring, with the specific timing varying by latitude.1

These interactions are described as strenuous affairs. During the process, the male typically engages in an exhaustive chase, during which he tightly grasps the female’s tail with his bill. Because platypuses are generally solitary and avoid each other outside of the breeding season, these behaviors serve as part of the reproductive process that leads to the consummatory sexual act.123

It is important to note that male platypuses are particularly aggressive during the breeding season and may fight other males, using sharp spurs on their hind ankles to inflict wounds. Following these mating interactions, the male takes no part in rearing the young; the female instead constructs a nursery burrow to lay and incubate her eggs.1