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The HoneyComb Paradigm for Research on Collective Human Behavior
Published on: January 19, 2019
The hydra effect, bubbles, and chaos in a simple discrete population model with constant effort harvesting
Eduardo Liz1, Alfonso Ruiz-Herrera
1Departamento de Matemática Aplicada II, ETSI Telecomunicación, Universidad de Vigo, Campus Marcosende, 36310 Vigo, Spain. eliz@dma.uvigo.es
Abstract:
We analyze the effects of a strategy of constant effort harvesting in the global dynamics of a one-dimensional discrete population model that includes density-independent survivorship of adults and overcompensating density dependence. We discuss the phenomenon of bubbling (which indicates that harvesting can magnify fluctuations in population abundance) and the hydra effect, which means that the stock size gets larger as harvesting rate increases. Moreover, we show that the system displays chaotic behaviour under the combination of high per capita recruitment and small survivorship rates.
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