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Geology topics

C.S. Robbins

Publications and source records attributed to C.S. Robbins.

At least 199 records · Page 11Linked to original sources
USGS1980

Techniques and results of nongame bird monitoring in North America

Long-term bird population trends based on accumulated ratios (proportional change) sometimes give a very misleading view of population change. Alternate methods of representing population change, based on the weighted means for the individual years, avoid the dangers of using ratios. Some advantages and disadvantages of various weighting techniques are discussed.

Book chapter↗
USGS1980

Consistency in habitat preference of forest bird species

The important management conclusion that follows from our results is that the habitat requirements of most forest bird species, although quite specific for each species, apply generally throughout their breeding ranges. Thus a habitat management program that proves beneficial in one part of the breeding range of a species has a high likelihood of success in an area hundreds of kilometers away. Site-specific programs may be necessary for successful management of species whose habitat preferences change across their range. Alternatively, geographical variation in habitat use may indicate that a species' habitat requirements are easily met and that effective management for the species is more readily attained. Close monitoring of a species' response to specific management programs will be required to resolve whether species showing geographic variation in habitat preference are habitat specialists or simply habitat generalists with varying responses to habitat structure

Transactions of the North American Wildlife and Na↗
USGS1980

Predictions of future Nearctic landbird vagrants to Europe

Migratory habits of 3I species of vagrants from North America and 73 candidate species not recorded In elther Bntain or Ireland during the 30 years 1947-76 were analysed by multiple regresslon. There was a sIgnificant correlation between the number of British and Irish records and the west-to-east component of normal migration, standard deviation of body weight, mlgratory dIstance, and abundance on the west coast of the North Atlantic. The candidate specles were ranked in order of likelihood of successful transatlantic flight based on the four Input variables (table 2).

British Birds↗
USGS1979

Report forms

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Newsletter of the Hawk Migration Association of No↗