SREL Reprint #1810
Estimating population density of moles Scalopus aquaticus
using assessment lines
Gregory D. Hartman and John D. Krenz
Density was estimated for three populations of eastern moles Scalopus
aquaticus Linnaeus, 1758, in South Carolina using a trapping grid and
assessment lines. Assessment line data were based upon the repair of holes
punched into surface tunnels of the animals. Using a new method of analysis for
assessment line data, a logistic curve was fitted to the data. Density estimates
based upon these analyses were (95% confidence intervals in parentheses) 3.02
(1.90 - 4.98), 2.73 (1.48 - 12.52), and 1.71 (0.86 - 2.69) moles/ha. In previous
studies using assessment line data to estimate density, obtaining confidence
intervals for the density estimate presented theoretical problems. In this study,
Monte Carlo procedures were used to obtain an estimate of the approximate
95% confidence intervals for density. The analytical methods used in the present
study eliminate the concepts of boundary strip width (strict sense) and the
occurrence of distinctive zones with constant capture probabilities, and as such,
represent important conceptual improvements of the assessment line density
estimation method.
Key words: Scalopus aquaticus, Talpidae, assessment lines, population
density, South Carolina
SREL Reprint #1810
Hartman, G.D. and J.D. Krenz. 1993. Estimating population density of moles Scalopus aquaticus using assessment lines. Acta Theriologica 38:305-314.
