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James C. Lewis

Publications and source records attributed to James C. Lewis.

4 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↗
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↗