The black ducks with a green tinge refer to a few species of dark colored ducks that can sometimes appear to have a green iridescent sheen to their feathers. The most common black ducks that may show a green tinge are:
- The American Black Duck
- The Mexican Duck
- The Mottled Duck
These duck species inhabit various parts of North America and get their dark plumage from ancestral interbreeding between Mallards and black ducks. The green-tinged iridescence comes from light refracting off the feathers at certain angles. This iridescence is a structural color that results from microscopic light-scattering structures in the duck’s feathers.
In good lighting, the speculum (colored wing patch) on these ducks can shine with a brilliant emerald, teal, or even purple iridescence. This helps differentiate them from female Mallards and other dark ducks that lack iridescent speculums.
American Black Duck
The American Black Duck (scientific name: Anas rubripes) is a large dabbling duck species that breeds in eastern North America. The male and female American Black Duck are nearly identical in plumage.
Their bodies are a dark brown to black color with a lighter brown head. The speculum feathers have an iridescent green, purple, and bronze sheen. Their bill is olive-yellow, legs are orange-yellow, and eyes are brown.
American Black Ducks breed near wooded swamps, shallow lakes, and ponds across eastern Canada and the eastern United States. They forage for food by dabbling in shallow water and feeding on things like aquatic plants, insects, mollusks, and amphibians.
These birds are migratory and winter further south in coastal wetlands and marshes along the Atlantic and Gulf coasts. Declining habitat and hybridization with Mallards have caused American Black Duck populations to decrease significantly from their historical numbers. However, they remain abundant enough to be legally hunted during duck season throughout most of their range.
Range and Habitat
The American Black Duck breeds from central and eastern Canada (Manitoba to Nova Scotia), south to the Great Lakes states, and along the Atlantic coast to North Carolina. Its wintering range extends from coastal New England and the Mid-Atlantic coasts to the Gulf Coast from Florida to eastern Texas.
This species prefers freshwater wetlands with dense emergent vegetation, such as wet meadows, forested swamps, beaver ponds, and marshes. They also inhabit coastal salt marshes during the non-breeding season. Habitat loss and degradation have impacted black duck numbers over the past century.
Description
As their name implies, American Black Ducks are mostly blackish-brown in color. The male and female look identical, although the female may be slightly lighter in color. Their plumage is dark brown on the head, breast, and body. The speculum feathers shine with iridescent greens, purples, and bronzes – a key ID feature.
Other distinctive features include a pale white chin strap that extends up the neck, yellow eyes, an olive-yellow bill, and orange legs/feet. They are medium-large ducks that measure 19-26 inches long with a wingspan of 30-39 inches. Males average 2.5-3.5 lbs and females 2-3 lbs.
Diet
American Black Ducks forage by dabbling and tipping headfirst in shallow waters. They consume a wide variety of plant and animal foods, including:
- Aquatic plants and roots
- Seeds, grains, acorns
- Algae and cyanobacteria
- Aquatic insects/larvae
- Mollusks
- Crustaceans
- Frogs
- Small fish
They usually feed during dusk, dawn, and throughout the night when hunting pressure is lower. Their diverse diet allows them to inhabit and breed in a wide range of wetland habitats across North America.
Breeding and Nesting
American Black Ducks begin pairing up on wintering grounds or during spring migration to breeding areas. They are monogamous throughout the breeding season. Nests consist of a bowl of leaves, grasses, and down feathers built on the ground near water.
Nesting occurs from April-July, with peak activity in May-June. The female lays 9-13 oval white/greenish-white eggs and incubates them for about 28 days until hatching. Ducklings fledge at around 8 weeks old. Brood parasitism by Redheads and Ruddy Ducks is common.
Mexican Duck
The Mexican Duck (Anas diazi) is a dabbling duck closely related to the Mallard. As their name implies, they are native to Mexico and parts of the Southwestern United States. The speculum feathers of male and female Mexican Ducks display an iridescent green sheen when in flight.
Some key identification features of Mexican Ducks include:
- Dark brown body plumage
- Iridescent green speculum
- Yellow bill with black saddles
- Reddish feet and legs
Mexican Ducks inhabit shallow lakes, marshes, ponds, and wetlands mainly in Mexico and some southwestern border regions of the U.S. They are non-migratory and live year-round within their resident ranges. Mexican Ducks interbreed with Mallards, producing hybrid ducks.
Range
The natural breeding range of the Mexican Duck extends from the U.S.-Mexico border south through western Mexico. Their range reaches as far south as Oaxaca.
In the U.S., small populations occur in Texas, New Mexico, Arizona, and California – mostly in areas along the Rio Grande River. Range expansions have increased the populations of Mexican Ducks found in Texas and New Mexico.
Description
Mexican Ducks measure 16-19 inches in length and weigh around 1.5-2.5 pounds. Their eyes are brown, bills are yellowish with black blotches (similar to Mallards), and legs/feet are reddish-orange.
Male Mexican Ducks have an iridescent purple-green speculum, bronze-colored heads, gray bodies, a white neck ring, and a black tail. Females are mostly mottled brown but also display the iridescent green wing patches. Both sexes have pale vertical barring on their flanks.
Habitat and Diet
Mexican Ducks inhabit lakes, ponds, marshes, streams, and reservoirs that are surrounded by aquatic vegetation. They prefer shallow, freshwater wetlands and riparian areas with lots of emergent plant cover to hide nests and ducklings.
Their diet consists mainly of plant matter that is obtained by dabbling and filtering items from the water’s surface. Foods include algae, seeds, leaves, stems, and grains. They will also eat some insects, mollusks, and crustaceans to supplement their diet.
Breeding and Conservation
Mexican Ducks begin breeding in the spring, with males performing courtship displays to attract mates. Nests consist of down feathers and vegetation built on the ground near water. Females lay 8-15 eggs that incubate for 25-28 days.
Broods break up after about 10 weeks when the ducklings fledge and become independent. Hybridization with Mallards may threaten the genetic integrity of pure Mexican Duck populations. Habitat loss also contributes to declining numbers.
Mottled Duck
The Mottled Duck (Anas fulvigula) is a dabbling duck species native to the Gulf Coast region of the southern United States and Mexico. They are non-migratory waterfowl named for their mottled brown and grey plumage. Their wing patches display an iridescent green sheen.
Some key facts about Mottled Ducks:
- Closely related to the American Black Duck and Mallard
- Found year-round along the Gulf Coast
- Habitats include coastal marshes, ponds, and estuaries
- Omnivorous diet – eats plants, seeds, and aquatic invertebrates
The Mottled Duck remains a popular game bird for waterfowl hunting in the coastal regions it inhabits. Their numbers are stable, though breeding populations face threats from habitat loss.
Range and Habitat
Mottled Ducks are year-round residents of the Gulf Coast, with their range centered on coastal Louisiana and Texas. They occur from Alabama to northeastern Mexico.
Within their coastal range, Mottled Ducks prefer shallow wetland habitats, including:
- Fresh and brackish marshes
- Ponds and lakes
- Estuaries and bayous
- Flooded agricultural fields
- Islands and beaches with standing water
They avoid marine habitats like open bays, beaches, and barrier islands. Mottled Ducks nest on dry land near water sources.
Description
Mottled Ducks are medium-sized, with a stout body shape. Their plumage is intricately patterned with brown, black, white, and gray mottling. The speculum is iridescent green with a trailing black band.
Other features include a yellow bill, brown eyes, and orange legs and feet. Males and females look very similar, but males have a pale blue bill band while females do not. Length ranges from 17-24 inches; weight 1.5-2.5 pounds.
Diet and Feeding
The Mottled Duck diet is omnivorous but heavily plant-based. Foods include:
- Seeds of grasses/sedges
- Leaves, stems, roots
- Algae
- Acorns
- Aquatic invertebrates
- Insects
- Mollusks
- Crustaceans
- Some small fish
They feed by dabbling and upending in shallow wetlands. Mottled ducks will also graze in nearby agricultural fields and meadows. They mostly forage at dawn and dusk.
Breeding
Mottled Ducks breed in the early spring following the rainy season. Males court females with displays and vocalizations for several weeks before pairing off.
Nests consist of down feathers and plant material located on the ground in dense vegetation near water. The female lays 9-12 eggs and incubates them 24-28 days until hatching. Ducklings fledge in about 2 months.
Conservation
Habitat loss in Gulf Coast wetlands due to urban development, pollution, and erosion are primary conservation threats to Mottled Duck populations. Their limited range and small global population (est. 400,000) also makes them vulnerable.
While still abundant as a game species, substantial declines could occur if coastal habitat degradation continues. Protection of wetland habitats will benefit Mottled Ducks and many other species relying on the Gulf Coast ecosystem.
Conclusion
In summary, the black ducks with green iridescent feathers seen in North America include the American Black Duck, Mexican Duck, and Mottled Duck. This sheen results from structural coloration of their wing speculum feathers. These ducks thrive in wetland habitats across the continent.
While the American Black Duck breeds across Canada and the eastern U.S., the Mexican Duck and Mottled Duck have more restricted ranges centered on the Gulf Coast region. All three ducks play important roles in wetland ecosystems and have significant value to recreational waterfowl hunters.
Conservation efforts aimed at preserving essential wetland habitats will benefit the continued survival of these beautiful black duck species and their unique green plumage. With ongoing habitat protection, they will continue gracing North American waterways for generations to come.
