| Abstract: | Work in rugged terrain poses some unique problems that should be considered before research is initiated. Besides the obvious physical difficulties of crossing uneven terrain, topography can influence the bird species? composition of a forest and the observer‘s ability to detect birds and estimate distances. Census results can also be affected by the slower rate of travel on rugged terrain. Density figures may be higher than results obtained from censuses in similar habitat on level terrain because of the greater likelihood of double-recording of individuals and of recording species that sing infrequently. In selecting a census technique, the researcher should weigh the efficiency and applicability of a technique for the objectives of his study in light of the added difficulties posed by rugged terrain. The variable circular-plot method is probably the most effective technique for estimating bird numbers. Bird counts and distance estimates are facilitated because the observer is stationary, and calculations of species? densities take into account differences in effective area covered amongst stations due to variability in terrain or vegetation structure. Institution of precautions that minimize the risk of injury to field personnel can often enhance the observer?s ability to detect birds. |
| Genre: | Book chapter |
| ProdID: | 5210365 |
| Citation Author: | Dawson, D.K. |
| Citation Contributing Office: | Patuxent Wildlife Research Center |
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| Citation Editor: | Ralph, C. John; Scott, J. Michael (editors) |
| Citation End Page: | 315 |
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| Citation Language: | English |
| Citation Larger Work Title: | Estimating Numbers of Terrestrial Birds |
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| Citation Phsyical Description: | x, 630 |
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| Citation Publisher: | Cooper Ornithological Society |
| Citation Series: | Studies in Avian Biology |
| Citation Series Code: | |
| Citation Series Number: | 6 |
| Citation Search Results Text: | Sampling in rugged terrain; 1981; Book chapter; 6; Estimating Numbers of Terrestrial Birds; Dawson, D.K. |
| Citation Start Page: | 311 |
| Citation Volume: | |
| Citation Year: | 1981 |
| Type: | citation/reference |
| Text: | Sampling in rugged terrain; 1981; Book chapter; 6; Estimating Numbers of Terrestrial Birds; Dawson, D.K. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Tue, 9 Jun 2009 09:23 -0500 |
| Publisher: | Cooper Ornithological Society |
