Ea. Forys et Sr. Humphrey, COMPARISON OF 2 METHODS TO ESTIMATE DENSITY OF AN ENDANGERED LAGOMORPH, The Journal of wildlife management, 61(1), 1997, pp. 86-92
We estimated densities of the endangered Lower Keys marsh rabbit (Sylv
ilagus palustris hefneri) at 5 habitat patches on Boca Chica Key, Monr
oe County, Florida, using pellet counting and direct enumeration from
livetrapping. We compared density estimates from these 2 methods to an
independent estimation of population size based on radiotracking data
to determine which method would be best for long-term population moni
toring. Density estimates were made 3 times per year for 2.5 years fro
m March 1991 to July 1993. Significant correlations were found between
pellet counting and radiotelemetry estimates (r(2) = 0.89, p < 0.0001
) and between the livetrapping and radiotelemetry estimates (r(2) = 0.
99, p < 0.0001). Pellet-counting estimates took 80% less time to perfo
rm than livetrapping estimates. Although livetrapping may have a highe
r correlation with actual population density, pellet counting provides
an economic and efficient estimate that is well suited to long-term p
opulation monitoring.