Mallard (Anas platyrhynchos) – Wildlife of Japan
Introduction
The Mallard is a classic dabbling duck widely distributed across the Northern Hemisphere. In Japan, it is a common winter visitor throughout the country and a local breeder mainly in Hokkaidō and upland Honshū.
Appearance
About 59 cm long. Males have a glossy green head, white neck-ring, chestnut breast, gray body, and a violet-blue speculum edged in white. Females are mottled brown with an orange-tinged bill.
Habitat & Distribution
Found in lakes, rivers, reservoirs, and estuaries throughout Japan. It winters nationwide and breeds mainly in Hokkaidō, occasionally in upland Honshū. In winter, large flocks feed in rice paddies and shallow wetlands, sometimes at night.
Where to See in Japan
Easily observed from late autumn to early spring in parks, rivers, and ponds across Honshū, Shikoku, and Kyūshū. In Hokkaidō, Mallards are present year-round. Flooded paddies often host feeding groups at dusk.
Behavior
A typical dabbling duck that tips forward to feed instead of diving. Rests communally during the day and often feeds at night. Courtship displays begin in late winter.
Diet
Omnivorous—feeds on aquatic plants, seeds, insects, mollusks, and small crustaceans. Occasionally grazes or takes grain in fields.
Reproduction
Breeds mainly in Hokkaidō and occasionally in upland Honshū. The nesting season runs April to August. Nests are built on the ground near water, hidden in vegetation.
Conservation
Globally listed as Least Concern (LC) by IUCN. In Japan it is not on the national Red List, though some prefectures list it regionally.
Notes on Feral or Hybrid Birds
Domestic ducks derived from Mallards and hybrids (especially with Spot-billed Ducks) sometimes appear in parks and ponds, which can make identification tricky.
Author’s Impression
The Mallard is not a rare species, yet I can’t help but watch their calm, relaxed way of life for a long time.
On still winter mornings, the chorus of soft quacks echoes across park ponds. When sunlight catches the drakes’ violet speculums, the water shimmers with color.
I encountered this pair resting together for a midday nap in the cold, a peaceful scene that perfectly captured their gentle nature.
