Optimal Levy-flight foraging in a finite landscape

摘要

We present a simple model to study Levy-flight foraging with a power-law step-size distribution P(I) proportional to I-mu in a finite landscape with countable targets. We find that different optimal foraging strategies characterized by a wide range of power-law exponent mu(opt), from ballistic motion (mu(opt) -> 1) to Levy flight (1 < mu(opt) < 3) to Brownian motion (mu(opt) >= 3), may arise in adaptation to the interplay between the termination of foraging, which is regulated by the number of foraging steps, and the environmental context of the landscape, namely the landscape size and number of targets. We further demonstrate that stochastic returning can be another significant factor that affects the foraging efficiency and optimality of foraging strategy. Our study provides a new perspective on Levy-flight foraging, opens newavenues for investigating the interaction between foraging dynamics and the environment and offers a realistic framework for analysing animal movement patterns from empirical data.