Mottled Duck

Anas fulvigula

(c) John Van De Graaff
  • ANATIDAE
  • Swans, Geese, Ducks
  • Anseriformes
  • Pato tejano
  • Canard brun
Introduction
This coastal duck of the American southeast can be easily confused with the American Black Duck or the female Mallard; the three species are closely related, and differences in plumage can be subtle. Of these similar species, the Mottled Duck has the most restricted range, breeding mainly around the Gulf Coast, far south of either of its relatives.
Appearance Description
The Mottled Duck is very similar in appearance to the American Black Duck and to the female Mallard, although it is slightly smaller than the latter, with a lighter head, and brighter cheeks and throat. The bird is brown overall, darker on the body than on the head and neck. Males and females are almost identical, with males slightly darker. Its Latin name, fulvigula, means "tawny throat." Adults' bills are olive to yellow, and their legs are orange.
Range Map
Courtesy Kenn Kaufman
Range Distribution
The Mottled Duck resides across most of Florida, and westward around the Gulf Coast. The bulk of the population is found in the coastal marshlands of Louisiana and Texas, and in lesser numbers as far south as Mexico's eastern coast. The species was introduced to coastal South Carolina in 1976, and is now an established resident. There are few records away from the breeding range, and none outside of the Americas.
A legend for the range map to the right can be found here.
Habitat
The Mottled Duck prefers coastal marshes and wetlands with shallow, fresh water and plenty of vegetation. Coastal agricultural areas, particularly rice fields, have become increasingly important to the species. Large post-breeding concentrations can be found during the rice harvest in coastal Texas and Louisiana.
 
In central Florida, recent drainage of swamp land for agricultural use has opened up a new niche for the species. The Mottled Duck currently thrives on seasonally flooded agricultural fields, particularly within the Everglades Agricultural Area. Ironically, current Everglades land reforms designed to decrease agricultural use and restore the area to a more natural state are proving just as detrimental to the Mottled Duck as drainage of its natural Gulf Coast wetland habitat has been.
Feeding
As with many duck species, Mottled Ducks have a varied diet. Their main food source is grass seeds, rice, and aquatic vegetation, but they also feed upon invertebrates and small fish. In fall, large concentrations of Mottled Ducks can be found foraging in freshly harvested rice fields.
Reproduction
Pair formation takes place as early as August, much sooner than for other ducks. This helps reduce the risk of hybridization with Mallards, which generally pair much later. Nesting takes place as early as March. The female typically chooses a nest site on the ground in a grassy area near water. Less frequently, nests are suspended in grass, up to three feet above the ground. In Florida, Mottled Ducks are apt to choose atypical nest sites on agricultural land; they have been found nesting in tomato, watermelon, and sugar cane fields, as well as along irrigation ditches. Ducklings are raised by the female. The male may be present after hatching, but plays no role in the rearing of young.
Migration
The Mottled Duck is a non-migratory species. Short seasonal movements are thought to be in response to temporary factors, such as dry seasonal wetlands or food shortages.
CBC Graph
Graph Legend
Annual Population Indices
  • 660,000
  • 660,000
  • very small range and serious threats to breeding
Population Status Trends
Due to its limited range and relatively small global population, the Mottled Duck is particularly vulnerable to habitat loss and other pressures. The species' slow decline throughout its range has earned it "Yellow" status on Audubon's WatchList of North American birds. The species may also be susceptible to significant population swings, due to drought and other natural factors.
 
An explanation of the Annual Population Indices graph displayed to the right can be found here.
Conservation Issues
The Mottled Duck has a fairly limited range, and requires very specific coastal marshland and prairie habitat. The species' fate is tied to its habitat; as coastal marshland is drained, developed, or lost to hurricanes, Mottled Ducks become increasingly threatened. Another threat to the species' survival is hybridization. Each year, particularly in Florida, significant numbers of escaped and released domesticated Mallards breed with wild Mottled Ducks, thus decreasing the number of true Mottled Ducks.
What You Can Do
Remain aware of local, regional, and federal land management decisions, particularly those that affect our wetlands.
 
Contact your legislators in support of wise land management initiatives, such as wetland restoration along the Gulf Coast, and The North American Waterfowl Management Plan.
 
For actions you can take, including Audubon activities, please visit our resources page.
More Information
Ducks Unlimited maintains important information on many issues affecting North American waterfowl: http://www.ducks.org/conservation/index.asp
 
The marshland of coastal Louisiana is crucial habitat for many waterbird species, including Mottled Ducks. America's Wetland, a campaign to save coastal Louisiana, maintains timely information regarding coastal land loss at its website: http://www.americaswetland.com/.
 
Visit our resources page for more information about this species.
Natural History References
Bent, Arthur Cleveland. 1962. Life Histories of North American Wild Fowl: Part One. Dover Publications, Inc., New York.
 
Kaufman, Kenn. 1996. Lives of North American Birds. Houghton Mifflin Company, New York.
 
Kortright, Francis H. 1943. The Ducks, Geese and Swans of North America. The American Wildlife Institute, Washington D.C.
 
Moorman, T. E. and P. N. Gray. 1994. Mottled Duck (Anas fulvigula). In The Birds of North America, No. 81 (A. Poole and F. Gill, Eds.). Philadelphia: The Academy of Natural Sciences; Washington, D.C.: The American Ornithologists' Union.
Conservation Status References
Kaufman, Kenn. 1996. Lives of North American Birds. Houghton Mifflin Company, New York.
 
Kortright, Francis H. 1943. The Ducks, Geese and Swans of North America. The American Wildlife Institute, Washington D.C.
 
Moorman, T. E. and P. N. Gray. 1994. Mottled Duck (Anas fulvigula). In The Birds of North America, No. 81 (A. Poole and F. Gill, Eds.). Philadelphia: The Academy of Natural Sciences; Washington, D.C.: The American Ornithologists' Union.