Population extinction in an inhomogeneous host-pathogen model

TL;DR

This paper models the spread of a pathogen in an inhomogeneous lake basin system, revealing how infection propagates and leads to amphibian extinction, with extinction times depending on host and pathogen parameters.

Contribution

It introduces a quenched disorder model for host-pathogen dynamics in a spatially inhomogeneous environment, analyzing extinction times and threshold behaviors.

Findings

Pathogen spreads in a wave-like pattern across lakes.

Extinction time depends on host population and pathogen growth rate.

Steady state host population exhibits threshold behavior.

Abstract

We study inhomogeneous host-pathogen dynamics to model the global amphibian population extinction in a lake basin system. The lake basin system is modeled as quenched disorder. In this model we show that once the pathogen arrives at the lake basin it spreads from one lake to another, eventually spreading to the entire lake basin system in a wave like pattern. The extinction time has been found to depend on the steady state host population and pathogen growth rate. Linear estimate of the extinction time is computed. The steady state host population shows a threshold behavior in the interaction strength for a given growth rate.