Estimating numbers of birds by point counts: how long should counts last?
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چکیده
منابع مشابه
Point Counts of Birds: What Are We Estimating?
Point counts of birds are made for many reasons, including estimating local densities, determining population trends, assessing habitat preferences, and exploiting the activities of recreational birdwatchers. Problems arise unless there is a clear understanding of what point counts mean in terms of actual populations of birds. Criteria for conducting point counts depend strongly on the purposes...
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collection of data which will facilitate comparisons among projects. The standards identified should permit any manager to develop an appropriate monitoring or research program. Data generated from these programs will have a number of valuable uses beyond local assessments. Population trends from National Parks and other protected areas will permit comparisons of species in wilderness areas wit...
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An important characteristic of any software is its size. Frequently used metrics for measuring the size of software are source lines of code (SLOC) and function points. Lines of code are easy to count and seem unambiguous (but different definitions can cause variations of 500%). Function points are normally counted by certified professionals, which may introduce differences between counters. In...
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Roadside point counts are generally used for large surveys to increase the number of samples. We examined differences in species detected from roadside versus off-road (200-m and 400-m) point counts in the Shenandoah National Park. We also compared the list of species detected in the first 3 minutes to those detected in 10 minutes for potential species biases. Results from 81 paired roadside an...
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ژورنال
عنوان ژورنال: Bird Study
سال: 1984
ISSN: 0006-3657,1944-6705
DOI: 10.1080/00063658409476841