Incidence of the El Niño–Southern Oscillation Cycle on the Existing Fundamental Niche and Establishment Risk of Some Anastrepha Species (Diptera-Tephritidae) of Horticultural Importance in the Neotropics and Panama

TL;DR

This study examines how climate patterns like El Niño affect the habitats and spread risks of fruit fly species in the Neotropics.

Contribution

The novelty lies in modeling how ENSO cycles influence the ecological niches and establishment risks of Anastrepha species.

Findings

Fundamental niches of four Anastrepha species changed across different ENSO episodes.

Species showed varying levels of environmental similarity during different ENSO phases.

Risk maps for species establishment were developed to aid pest management planning.

Abstract

Previous studies following this research allow us to contribute to the importance of potential distribution models of species and ecological niches. The Anastrepha genus, considered one of the most important at a quarantine level, demands a constant search for information to understand different ecological dynamics. We characterised the fundamental niches of four Anastrepha species in different El Niño–Southern Oscillation (ENSO) episodes (El Niño, El Neutro and La Niña) with ecological niche modelling in NicheA software 3.0. The results of a comparison of the ellipsoids that represent the fundamental niche existing for the species showed changes in the El Niño, El Neutro and La Niña episodes. Furthermore, when making a comparison between Anastrepha species and the different ENSO climatic episodes, we found that they share great environmental similarity between them. Finally, our results present different levels of risk of establishment of these species in the Neotropics, which will allow us to develop efficient plans for integrated pest management.

To compare the environmental space of four Anastrepha species in different ENSO episodes (El Niño, El Neutro and La Niña), we built ecological niche models with NicheA software. We analysed the fundamental niche and the combined establishment risk maps of these species developed with the ArcGisPro combine geoprocess. A comparison of the ellipsoids that represent the fundamental niche existing for the species showed changes in the El Niño, El Neutro and La Niña episodes. For A. grandis in the El Niño vs. El Neutro episodes, there was a Jaccard index of 0.3841, while the comparison between the La Niña vs. El Neutro episodes presented a Jaccard index of 0.6192. A. serpentina in the El Niño vs. El Neutro and La Niña vs. El Neutro episodes presented Jaccard indices of 0.3281 and 0.6328, respectively. For A. obliqua, the comparison between the El Niño vs. El Neutro and La Niña vs. El Neutro episodes presented Jaccard indices of 0.3518 and 0.7472, respectively. For A. striata, comparisons between the episodes of El Niño vs. El Neutro and La Niña vs. El Neutro presented Jaccard indices of 0.3325 and 0.6022, respectively. When studying the comparison between Anastrepha species and the different ENSO climatic episodes, we found that in the El Niño episode, the comparisons with the best environmental similarity were A. obliqua vs. A. striata and A. obliqua vs. A. serpentina, with higher Jaccard indices (0.6064 and 0.6316, respectively). In the El Neutro episode, the comparisons with the best environmental similarity were A. serpentina vs. A. striata and A. obliqua vs. A. striata, which presented higher Jaccard indices (0.4616 and 0.6411, respectively). In the La Niña episode, the comparisons that presented the best environmental similarity were A. obliqua vs. A. serpentina and A. obliqua vs. A. striata, with higher Jaccard indices (0.5982 and 0.6228, respectively). Likewise, our results present the risk maps for the establishment of these species throughout the Neotropics, allowing us to predict the level of risk in order to develop integrated pest management plans.

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