The impact of environmental noise on animal communication: pattern formation in a class of deterministic and stochastic hyperbolic models for self-organised biological aggregations

Abstract

The collective movement of animals occurs as a result of communicationbetween the members of the community. However, inter-individual commu-nication can be aected by the stochasticity of the environment, leading tochanges in the perception of neighbours and subsequent changes in individualbehaviour, which then in uence the overall behaviour of the animal aggre-gations. To investigate the eect of noise on the overall behaviour of animalaggregations, we consider a class of nonlocal stochastic and deterministic hy-perbolic models for the collective movement of animals. We show numericallythat strong noise does not seem to in uence the spatio-temporal pattern (i.e.,travelling aggregations) observed when all neighbours are perceived with thesame intensity (i.e., the environment is homogeneous). However, when neigh-bours ahead/behind are perceived dierently by a reference individual, noisecan lead to the destruction of the spatio-temporal pattern. Moreover, weshow that the increase in noise can lead to dierent transitions between dif-ferent spatio-temporal patterns, and these transitions are relatively similarto the transitions between patterns when we perturb deterministically someparameters.