Variation in environmental stochasticity dramatically affects viability and extinction time in a predator-prey system with high prey group cohesion

Copyright © 2023 Elsevier Inc. All rights reserved..

Understanding how tipping points arise is critical for population protection and ecosystem robustness. This work evaluates the impact of environmental stochasticity on the emergence of tipping points in a predator-prey system subject to the Allee effect and Holling type IV functional response, modeling an environment in which the prey has high group cohesion. We analyze the relationship between stochasticity and the probability and time that predator and prey populations in our model tip between different steady states. We evaluate the safety from extinction of different population values for each species, and accordingly assign extinction warning levels to these population values. Our analysis suggests that the effects of environmental stochasticity on tipping phenomena are scenario-dependent but follow a few interpretable trends. The probability of tipping towards a steady state in which one or both species go extinct generally monotonically increased with noise intensity, while the probability of tipping towards a more favorable steady state (in which more species were viable) usually peaked at intermediate noise intensity. For tipping between two equilibria where a given species was at risk of extinction in one equilibrium but not the other, noise affecting that species had greater impact on tipping probability than noise affecting the other species. Noise in the predator population facilitated quicker tipping to extinction equilibria, whereas prey noise instead often slowed down extinction. Changes in warning level for initial population values due to noise were most apparent near attraction basin boundaries, but noise of sufficient magnitude (especially in the predator population) could alter risk even far away from these boundaries. Our model provides critical theoretical insights for the conservation of population diversity: management criteria and early warning signals can be developed based on our results to keep populations away from destructive critical thresholds.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:365

Enthalten in:

Mathematical biosciences - 365(2023) vom: 19. Sept., Seite 109075

Sprache:

Englisch

Beteiligte Personen:

Feng, Tao [VerfasserIn]
Milne, Russell [VerfasserIn]
Wang, Hao [VerfasserIn]

Links:

Volltext

Themen:

Allee effect
Holling type IV functional response
Journal Article
Noise-induced tipping
Predator–prey model

Anmerkungen:

Date Revised 28.09.2023

published: Print-Electronic

Citation Status Publisher

doi:

10.1016/j.mbs.2023.109075

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM362311420