Important Bird Areas

Catahoula-Dewey Wills-Three Rivers

Louisiana

Catahoula-Dewey Wills-Three Rivers IBA includes four National Wildlife Refuges and six wildlife management areas. These include Bayou Cocodrie, Catahoula, Cat Island, and Lake Ophelia NWRs, and Dewey Wills, Grassy Lake, Pomme de Terre, Red River, Spring Bayou, and Three Rivers WMAs.

This site is part of the Mississippi flyway, a major migratory bird corridor, and comprises the Black, Red, and Mississippi floodplains. The terrain is flat and the drainage is poor. The land is crisscrossed by several major rivers, including the Mississippi, the Red, Lower Old River, and the Black River, as well as many bayous, sloughs, and lakes. Prior to levying of the Mississippi River, this area was subject to annual flooding, and some land still floods. The habitat is primarily bottomland hardwood forest, mixed with some baldcypress-tupelo swamp. Some of the private land has been cleared for agriculture, much of it rice.

Catahoula Lake, the largest freshwater lake in Louisiana, is a RAMSAR Wetland of International Importance long considered Louisiana?s most important inland wetland for waterbirds and shorebirds. The long, shallow lake experiences major seasonal water level fluctuations. The current lake management plan, under the joint responsibility of the U.S. Army Corps of Engineers and the LA Department of Wildlife and Fisheries, is designed primarily to provide optimal habitat for migratory birds. At high water levels, Catahoula Lake covers over 46 square miles. During drawdown, this large, shallow, poorly drained wetland provides habitat for shorebirds, waterfowl, sport and commercial fishes. Catahoula Lake is a unique wetland type with the most extensive stands of wild chufa and millet in LaSalle, Grant and Rapides parishes. These stands of vegetation provide excellent food for waterfowl and shorebirds and contribute to the biodiversity of the site. The outer edges of the lake support woody plants, including bald cypress and swamp privet.

Ornithological Summary

Catahoula-Dewey Wills-Three Rivers IBA provides habitat for significant numbers of waterfowl, shorebirds, Neotropical migratory songbirds, raptors, and game birds.

Many of the public properties within this IBA are managed to provide habitat for wintering waterfowl. Catahoula Lake and the immediate surrounding wetlands support from 40,000 to 300,000 ducks from October to January, including up to 25% or more of the nation wide recorded population of Canvasbacks. The IBA also supports significant numbers of wintering Gadwall, Green-winged Teal, Northern Pintail, Ring-necked Duck, Mallard, American Widgeon, and Northern Shoveler, as well as resident Wood Ducks.

Catahoula Lake also supports significant shorebird populations. A conservative estimate of the shorebird population in a single day on Catahoula Lake alone ranges from 4,000 to 70,000 shorebirds.
Throughout the IBA, there are species of conservation concern including Prothonotary Warbler, Swainson?s Warbler, American Woodcock, Solitary Sandpiper, Kentucky Warbler, Little Blue Heron, and Bald Eagle.

Wading birds are common on the IBA, including Great Blue Heron, Little Blue Heron, Great Egret, Snowy Egret, Tri-colored Heron, Cattle Egret, Least and American Bittern, White, Glossy and White-faced Ibis, Wood Stork, and Roseate Spoonbill.

Other groups of birds of interest include 7 species of woodpeckers, 7 species of flycatchers, 5 species of wrens, 21 warbler species, and 15 species in the Emberizid sparrow complex.

Conservation Issues

Hydrologic alteration and the resultant effects of increased siltation, changes in flow of sediments, and development of the floodplain are the greatest threats on this IBA.

Lead shot deposition on the lakebed from hunting was a significant problem at Catahoula Lake. The lead shot ban of 1987 has reduced, but not eliminated this problem. The current impact of lead shot on waterfowl survival is unknown.

While oil and gas spills have been reduced, they pose a potential threat to the lake and wetland habitats. Changes in hydrology for navigation have increased siltation in the natural channel in Little River. The construction of the Ouachita-Black Rivers navigation project caused woody vegetation encroachment into the mudflats. There is not a good approved herbicide to control woody plant invasion, and funding for mechanical control has been lacking.

At the highest water levels, there are some property disputes between the state and adjacent private property owners. There are also continued attempts by commercial entities to submit development plans for the shoreline areas of Catahoula Lake.

Changes in agricultural policy may affect continued rice production on private agricultural lands, which is important for maintaining the avian populations in the region.

Ownership

Catahoula-Dewey Wills-Three Rivers IBA is an intermixed complex of state, federal, and privately owned lands. Four National Wildlife Refuges, including Bayou Cocodrie, Cat Island, Catahoula, and Lake Ophelia, are in the IBA. The state owns 6 wildlife management areas in the IBA, including Dewey Wills WMA, Grassy Lake WMA, Pomme de Terre WMA, Red River WMA, Spring Bayou WMA, and Three Rivers WMA. The U.S. Army Corps of Engineers owns some of the land within the Red River and Three Rivers WMAs.

Catahoula Lake itself, 12,150 hectares, is owned by the State of Louisiana, with management authority vested with the Louisiana Department of Wildlife and Fisheries. Other cooperators in the management plan include the U.S. Army Corps of Engineers and the U. S. Fish and Wildlife Service.

Delta Farms is approximately 26,820 hectares of privately owned agricultural lands. There are other privately owned lands in the IBA, many of them managed for a combination of hunting and agriculture.

Habitat

Catahoula Lake is a unique wetland type with the most extensive stands of wild chufa and millet in LaSalle, Grant and Rapides parishes. These stands of vegetation provide excellent food for waterfowl and shorebirds and contribute to the biodiversity of the site. The outer edges of the lake support woody plants, including some bald cypress and swamp privet.

Much of the terrain in this IBA is low and flat, with poor drainage. Much of it is bottomland hardwood forest subject to seasonal backwater flooding, with cypress-tupelo brakes, bayous, lakes, ponds, sloughs, and rivers throughout. The vegetation varies according to the elevation. Hackberry, locust, elm, ash, maple, and sweetgum tend to dominate the ridges. On higher elevations there may also be deciduous holly, hawthorn, swamp dogwood, peppervine, rattan vine, blackberry, and palmetto. The bottomlands contain overcup and nuttall oak, bitter pecan, ash, elm, sycamore, cottonwood, and willow oak. The understory of the flats also contains haws, deciduous holly, elderberry, poison ivy, swamp-privet, and native forbs and grasses. Open water areas contain water hyacinth, buttonbush, duck potato, duckweed, water primrose, and lotus.

Bayou Cocodrie and Cat Island National Wildlife Refuges both contain old growth baldcypress-tupelo swamp. Bayou Cocodrie protects one of the nation?s least disturbed bottomland hardwood forests, while Cat Island is home to the National Champion baldcypress, which is also the largest tree of any species east of the Sierra Nevada mountain range.

Agricultural areas provide rice for waterfowl and shorebirds, as well as cover for waterfowl during hunting seasons.

Land Use

Waterfowl hunting is the single largest use of land in the Catahoula Lake and NWR complex. In 2003, Ring-necked ducks, green-winged teal, and mallards were the most commonly shot ducks on the lake. Hunting is also allowed for deer, small game, and feral hogs. Fishing and a small amount of commercial angling occur on the lake, and to some degree, in the wildlife refuge.

Catahoula Lake and Catahoula NWR are used for flood control. Also, a significant portion of land use includes refuge, wildlife, and water level management. Water levels are primarily managed to provide suitable habitat for waterfowl, shorebirds, and wading birds. There is also some management to control invasive species and woody species encroachment into the wild chufa and millet stands.

There are about 30 active oil or gas wells on the lake bed. Additional land uses include various types of ecological research, sight seeing, bird watching, and environmental education.

Public lands throughout the IBA were primarily established to protect habitat for waterfowl, threatened and endangered species, and to conserve, restore, and manage native forested wetland habitats for natural resources. The site is in the Mississippi Flyway in a floodplain ecosystem, so is a major corridor for waterfowl, shorebirds, raptors, and Neotropical migrants. It is also a corridor for the endangered Louisiana black bear.

Throughout the IBA, activities include timber management, camping, ATV use, wildlife observation, hiking, photography, canoeing, and birding. Hunting is one of the primary uses on the WMAs, and includes hunting for deer, small game, and waterfowl, as well as sport and commercial fishing, crawfishing, and limited alligator harvest.

There is also environmental education, particularly on the NWRs, and some environmental restoration and conservation activities.

Agricultural production is the main land use of many of the private lands, as well as recreational hunting.