Sequential sampling designs for catching the tail of dispersal kernels

Abstract

Methods to design a sampling strategy should depend on the research question involved when conducting the experiment. The objective of this study is to design a seed trap configuration surrounding a parent plant when the long distance component of the seed dispersal kernel is of interest. In particular, as a population’s invasion speed depends mainly on the tail of the dispersal kernel, the sampling design in this study is based on calculating this quantity. The optimality criterion is to minimize the mean squared error (MSE) of the estimated invasion speed (using a limited number of traps) with respect to the “true” calculated invasion speed. Detailed procedures are given on how to calculate an invasion speed, both in a 1D and a 2D setting, with examples on how to implement the method to get a local optimal sampling strategy using Calluna vulgaris as a test system. Results show a trade-off between nearby sampling (many seeds, no long-distance dispersal measured) and distant sampling (few seeds, but long-distance dispersal measured).