Natural Resource BiometricsLine TransectHayne's EstimatorThe Hayne estimator was develop to estimate density of birds that flush as an observer comes within a certain radius. This method assumes that there is a fixed flushing distance r and all animals within r distance of the observer will flush. The density is estimated by : where:
n is the number of animals L is the length of the transect r_{i }is the sighting distance to the ith animal. R is the mean of the reciprocal of the sighting distances and is calculated as: The variance of the density estimate is calculated as : where: D_{H} is the Hayne density estimate n is the number of animals var(n) is the variance of n approximately equal to n r_{i }is the sighting distance to the ith animal.
Hayne method assumed that the mean sighing angle is 32.7^{o}. This can be tested by:
n is the number of animals sighted Theta is the mean observed sighting angle (Figure 1). The test would be if the Z value is greater than 1.96 or less than 1.96 the sighting angle is statistically different than 32.7^{o} at the alpha = 0.05 level. Also See: Chapter 2  Estimating Abundance: Line Transects pages 115121 in: Krebs, C. J. 1989. Ecological Methodology. Harper and Row, Publishers. New York. 654 pp.

Natural Resources Biometrics by David R. Larsen is licensed under a Creative Commons AttributionShareAlike 4.0 International License . Author: Dr. David R. Larsen Created: November 6, 1998 Last Updated: October 17, 2014 