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James C. Lewis

Publications and source records attributed to James C. Lewis.

5 recordsLinked to original sources
USGS2003

Motorized migrations: The future or mere fantasy?

In 15 experiments from 1993-2002, we led cranes, geese, or swans on their first southward migration with either ultralight aircraft or vehicles on the ground. These experiments reveal that large birds can be readily trained to follow and most will return north (and south) in subsequent migrations unassisted. These techniques can now be used to teach birds new (or forgotten) migration paths. Although we are constantly improving our training techniques, we now have an operational program that can be broadly applied to those species where juveniles learn migration routes from their parents.

Arizona, Florida, Idaho, Indiana, Maryland, New Me↗
USGS1984

Habitat Suitability Index Models: American black duck (wintering)

INTRODUCTION The American black duck, commonly known as the black duck, is migratory and has a wide geographic range. American black ducks breed from Cape Hatteras, North Carolina, west to the Mississippi River and north through the eastern Canadian boreal forest (Bellrose 1976). The winter range extends from the Rio Grande River on the Texas coast, northeast to Lake Michigan, east to Nova Scotia, south to Florida, and west to Texas (Wright 1954). American black ducks arrive on their wintering habitats between September and early December and remain there until February to April (Bellrose 1976). Their preferred habitat varies considerably through the wintering range. Habitat use appears related to food availability, freedom from disturbance, weather, and often upon the presence of large bodies of open water. These interrelated elements are essential for meeting the energy demands and other nutritional requirements of black ducks in response to the rigors of cold weather and migration. In the Atlantic Flyway, winter populations of American black ducks concentrate in marine and estuarine wetlands (U.S. Fish and Wildlife Service 1979). They use salt marshes and small tidal bays for feeding and loafing areas. In wintering areas north of Chesapeake Bay, American black ducks frequently feed on tidal flats and rest in emergent wetlands or on ice-free bays, rivers, and coastal reservoirs. In the Chesapeake bay area, migrant and wintering American black ducks occupy a wide variety of habitats (Stewart 1962). They strongly favor brackish bays with extensive adjacent agricultural lands. Estuarine bays, coastal salt marshes, tidal fresh marshes, and adjacent impoundments receive high usage. American black ducks also concentrate in forested wetlands in and adjacent to estuaries in the South Atlantic Flyway, especially in Virginia and North Carolina.

FWS/OBS↗
USGS1983

Habitat Suitability Index Models: Roseate spoonbill

The roseate spoonbill is a long-legged wading bird with a height of approximately 80 cm (31.5 inches), a wingspan of 1.3 m (4.3 ft), and a weight of 1.6 kg (3.5 Ib }. The bill is narrower near the base (2-3 em, 0.8-1.2 inches) than at the flattened tip (5 cm, 2 inches) and is 15-18 cm (5.9-7.1 inches) in length. Roseate spoonbills occur and nest in peninsular Florida, coastal Louisiana, and Texas, south through the West Indies, Mexico, Central and South America to Argentina and Chile. Marine, brackish, and freshwater habitats are utilized, but brackish areas are favored (Blacklock et al. 1978). In the late 1970·s there were 2,500 pairs nesting along the Texas coast (Texas Colonial Waterbird Society 1982), 1,300 pairs in southwestern Louisiana (Portnoy 1977), and 1,400 pairs in Florida (Robertson et al. 1983). These birds are resident year round in Florida, Louisiana, and Texas, but fewer bi rds are present duri ng the nonbreedi ng season than in the breeding season. Some individuals move northward after nesting and have been reported in Georgia, Nebraska, Pennsylvania, Utah, and Wisconsin, but most spoonbills move south when they leave the breeding area.

FWS/OBS↗
USGS1983

Habitat Suitability Index Models: Clapper rail

A review and synthesis of existing information were used to develop a model suitable for evaluating the quality of coastal habitat of clapper rails (Rallus longirostris). The model is scaled to produce an index of habitat suitability between 0 (unsuitable habitat) and 1 (optimally suitable habitat) for coastal areas of the continental United States. Habitat suitability indices are designed for use with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service. Guidelines for clapper rail model applications and techniques for estimating model variables are discussed.

FWS/OBS↗