Biological invasion drives ecosystem state and metabolism across tipping points

Gaigne, E.; Dezerald, O.; Gorzerino, C.; Coudreuse, J.; Bennevault, Y.; Pannard, A.; Edeline, E.

doi:10.64898/2026.04.16.718977

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bioRxiv · 10.64898/2026.04.16.718977

Biological invasion drives ecosystem state and metabolism across tipping points

Gaigne, E.·Dezerald, O.·Gorzerino, C.·Coudreuse, J.·Bennevault, Y.·Pannard, A.·Edeline, E.

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Abstract

Abrupt regime shifts of complex ecosystems between alternative stable states are widespread in nature. Yet, our mechanistic understanding of disturbance-shift-ecosystem functioning relationships remains poor, and it is further unclear whether biotic disturbances can drive such shifts. Using a 5-year pond experiment, we demonstrate that invasion by the red swamp crayfish (Procambarus clarkii) drove a regime shift from a clear-water, macrophyte-dominated, to a turbid, phytoplankton-dominated state. The regime shift was associated with increased water temperature due to increased water turbidity enhanced light absorption, and with a seasonal switch of ecosystem metabolism from hetero-to autotrophy due to decreased respiration in summer, despite constant gross primary production. Reducing crayfish population densities by 44 % failed to move ecosystems back towards their initial state and functioning. Our results stress that biotic disturbances may have hardly-reversible consequences on the biophysical and biogeochemical processes that support ecosystem functioning.

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Gaigne, E., Dezerald, O., Gorzerino, C., Coudreuse, J., Bennevault, Y., Pannard, A., Edeline, E.. 2026-04-21. Biological invasion drives ecosystem state and metabolism across tipping points. https://doi.org/10.64898/2026.04.16.718977

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