Abstract
Loach, Misgurnus anguillicaudatus, that inhabit paddy fields are an important food resource for higher-level consumers such as birds, and the quantity of the resource is of great concern for environmental conservation. In a previous study, we conducted an experiment to estimate Loach population size using a closed experimental paddy field, high density of sampling points in the field overall, removal of captured individuals, and DeLury’s linear model as well as the program CAPTURE, and reported that the estimated values were reasonably accurate and there was a possibility of a estimating the approximate population using limited data from rim-sampling points. In the present study, we set up fixed sampling points spaced at 2 m intervals near the paddy field rim where we could harvest Loach without stepping into the paddy, and examined the possibility of making simple population estimates using only those points’ data. We also examined the possibility of further reduction of the number of fixed sampling points for future general use. Our results indicate that those results are approximately proportional to the sub-area around the rim of the paddy field represented presumably by the sampled points. The result suggests that adequate estimates of Loach population may be obtainable at farms interested in implementing eco-friendly farming techniques.
