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J. M. Scott

Publications and source records attributed to J. M. Scott.

At least 55 records · Page 3Linked to original sources
USGS1984

Annual variation in the distribution, abundance, and habitat response of the palila ( Loxioides bailleui )

We studied the distribution, population size, and habitat response of the Palila ( Loxioides bailleui ) during the 1980-1984 nonbreeding seasons to infer factors that limit the population and to develop management strategies. Distribution was fairly constant from year to year. Palila were confined to the subalpine woodland on Mauna Kea on the island of Hawaii, occurred between 2,000 and 2,850 m elevation, and reached highest densities on the southwest slopes. The population showed large annual fluctuations, from 6,400 birds in 1981 to 2,000 in 1984. The width of woodland was the most important variable in determining habitat response. Palila were more common in areas with greater crown cover, taller trees, and a higher proportion of native plants in the understory. Annual variation in Palila density within a habitat reflected variation in levels of their staple food, mamane pods. The main limiting factors of the population appeared to be the availability of good habitat and levels of their staple food. Palila had strongly depressed densities in the Pohakuloa flats area. This low density could not be explained by gross habitat features or food levels. Site tenacity, thermal stress, disturbance, and disease were hypothesized explanations. Our study indicated that the most effective management strategies would be the removal of feral ungulates and certain noxious plants from Palila habitat and the extension of the woodland zone to areas now intensively grazed.

The Auk↗
USGS1981

Introduction

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Book chapter↗
USGS1981

Avian surveys of large geographical areas: A systematic approach

A multidisciplinary team approach was used to simultaneously map the distribution of birds, selected food items, and major vegetation types in 34,000- to 140,000-ha tracts in native Hawaiian forests. By using a team approach, large savings in time can be realized over attempts to conduct similar surveys of smaller scope, and a systems approach to management problems is made easier. The methods used in survey design, training observers, and documenting bird numbersand habitat descriptions are discussed in detail.

Wildlife Society Bulletin↗