In the breeding season, the Northern Waterthrush is found in a belt stretching from north central Alaska, east across all of the Canadian provinces. In the winter season, the species is found in the tropical mangroves of Central and South America.

Biogeographic Regions: nearctic (Native ); neotropical (Native )

The Northern Waterthrush is a large, ground walking warbler with a brown back and a white or yellowish streaked breast. The breast, sides, and flanks are streaked with a dark olive or black. There is an olive-colored triangular spot in the front of the eye and a crescent shaped mark on the lower eyelid. The throat is also covered with small triangular marks.

Average mass: 18.7 g.

Average basal metabolic rate: 0.28391 W.

The Northern Waterthrush prefers cool, dark, wooded swamps, thickets of bogs, margins of northern lakes, and willow and alder bordered rivers. During the spring and fall migration, the bird can be found in thick cover along streams, in marshes, and by stagnant pools.

Terrestrial Biomes: forest ; rainforest

Aquatic Biomes: lakes and ponds; rivers and streams

During the breeding season, the basic diet consists of larval and adult insects, spiders, and snails. After leaf emergence in the spring, the bird feeds on primarily on butterfly larvae. On the winter grounds, the bird consumes a greater variety of food, adding minnows and decapod crustaceans to its diet. The Northern Waterthrush forages alone using such tactics as twig gleaning, flycatching, hovering, chasing, and a lot of pecking. Microhabitats for foraging include water, ground, foilage, and air. Before leaf emergence, the Waterthrush typically spends about 75% of the time feeding in water, alternating between wading and walking along logs, on branches, and the water's edge.

Average lifespan

Status: wild: 107 months.

Pair bonding begins immediately after the female arrives on the breeding site. Males perch in trees that are standing near water while females are below usually feeding along the edge of the water. Males vibrate their wings and raise their crown feathers and sing. The female may answer with a chink. The pair bond is broken shortly after successful fledging. The male selects the general area of the nesting site, but the female chooses the actual nest site. Nests are usually in the cavity of a root system of wind-blown trees in a wooded swamp, on the side of a fern clump or under cover along the banks of a lake or a river. There is typically covering above the nest and an opening to one side. The exterior of the nest is mainly moss and liverwort gametophytes. The interior of the nest cup is constructed with grass stems, twigs, or pine needles, and then lined with the hair of deer, caribou, cow, and rabbit. Average clutch is composed of four white ovate eggs spotted with browns and greys. The female is solely responsible for incubation, which lasts 12 days. Both parents, however, share feeding responsibilities. After four to five weeks the chicks begin feeding themselves.

Average eggs per season: 4.

Degradation of habitat and pesticides are the biggest threats facing the species. Northern Waterthrush populations, however, have managed to remain stable despite these threats. Drainage of swamps for agriculture and wetland development into ponds or lakes may reduce breeding habitat. Pesticides are also affecting the Northern Waterthrush. Aerial spraying for the spruce budworm can kill the birds directly or reduce the biomass of their prey.

US Migratory Bird Act: protected

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

IUCN Red List of Threatened Species: least concern

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Feed on insects that are regarded as pests to humans.