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bioRxiv · 10.1101/2025.08.21.671467

Diverging effects of global change on future invasion risks of Agama picticauda between invaded regions: same problem, different solutions

Dubos, N.·Calesse, S.·Webster, K.·Bernet, C.·Deso, G.·Fieldsend, T. W.·Maoulida, S.·Mounir, S.·Porcel, X.·Probst, J.-M.·Saidou, H.·Souchet, J.·Ibouroi, M. T.·Roesch, M. A.
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Abstract

Predicting biological invasions is challenging because multiple factors can act in contrasting directions and exert heterogeneous effects across space. Nevertheless, modelling approaches provide valuable tools to anticipate the potential spread of invasive alien species and to support mitigation strategies. With an Ecological Niche Modelling approach, we predicted the invasion risks of Peterss Rock Agama Agama picticauda, a species that is spreading globally in non-forested areas through freight transport and un-/intentional releases from the pet trade. The potential establishment of the species in new areas is of concern for multiple endemic species throughout the world. We quantified the effects of climate, anthropogenic activity and forest cover on invasion risk. We used verified records from the native and non-native range and accounted for the latest methodological recommendations. We predicted how invasion risk will vary in the future (2070) using projections from two scenarios (SSP2 and SSP5). We predict that invasion risks will vary in diverging directions, depending on the region. The risk will increase in human-populated regions and on small islands but will decrease in Florida. We recommend increasing surveillance in vehicular transportation of material especially within the Comoros and the Mascarenes archipelagos. Since many introductions are related to the pet trade in Florida, we recommend stronger legal regulations and the promotion of public awareness. Promoting tree cover may be locally beneficial to prevent establishment of A. picticauda. The effect of climate change, land use change and human activities may differ between and within both, the native and the invaded regions. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=111 SRC="FIGDIR/small/671467v2_ufig1.gif" ALT="Figure 1"> View larger version (35K): org.highwire.dtl.DTLVardef@d623cforg.highwire.dtl.DTLVardef@c91271org.highwire.dtl.DTLVardef@d9f9beorg.highwire.dtl.DTLVardef@9b4b3b_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Dubos, N., Calesse, S., Webster, K., Bernet, C., Deso, G., Fieldsend, T. W., Maoulida, S., Mounir, S., Porcel, X., Probst, J.-M., Saidou, H., Souchet, J., Ibouroi, M. T., Roesch, M. A.. 2025-08-25. Diverging effects of global change on future invasion risks of Agama picticauda between invaded regions: same problem, different solutions. https://doi.org/10.1101/2025.08.21.671467

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