Fig 1.
The updated distribution map of the native and invaded occurrence records for Bactrocera Zonata collected from the Centre for Agriculture and Bioscience International (CABI) Invasive Species Compendium datasheet number 17694 (n = 37) [8], the Global Biodiversity Information Facility (GBIF) (n = 7) [48] and published articles (n = 7) [20,49–51].
In Sudan, updated georeferenced occurrence records of B. zonata (n = 57) were obtained from the Agricultural Research Corporation (ARC) of Sudan. “The figure was generated using the QGIS 3.10.2 software (https://qgis.org)”.
Table 1.
Worldclim bioclimatic variables used as potential predictor variables in the MaxEnt models [56].
The variables in bold were used in the final models of Bactrocera zonata’ climatic suitability after eliminating the highly correlated ones.
Fig 2.
The collinearity matrix for the candidate predictor variables for Bactrocera zonata.
The collinearity threshold was set at |r|>0.7 according to [61]. Darker shades of blue and red indicate high variable collinearity while lighter shades indicate low collinearity. Similarly, the smaller the circle the lower the correlation value.
Table 2.
The minimum and maximum values of the probability of an area being climatically suitable for Bactrocera zonata predicted by the five models under different climatic scenarios ran in MaxEnt.
Fig 3.
A complete flowchart depicting the datasets and processes employed in the present study.
Fig 4.
The global distribution of Bactrocera zonata host plants under rainfed and irrigated cropping systems in hectares obtained from the Spatial Production Allocation Model (MapSPAM 2005 v3.2) database [45].
“The figure was generated using the QGIS 3.10.2 software (https://qgis.org)”.
Table 3.
Contribution (%) of the eight bioclimatic variables [56] to the climatic suitability models.
Fig 5.
Maps of the climatic suitability of Bactrocera zonata under current (A) and four future climate change scenarios [i.e. four representative concentration pathways (RCPs)]–RCPs 2.6 (B), RCPs 4.5 (C), RCPs 6.0 (D) and RCPs 8.0 (E). The climatic suitability classes were: (i) not suitable (≤ 0.15), (ii) low suitability (0.16–0.30), (iii) medium suitability (0.31–0.60) and (iv) high suitability (≥ 0.61). “The figure was generated using the QGIS 3.10.2 software (https://qgis.org)”.
Table 4.
The AUC values for the five Bactrocera zonata climatic suitability models run in MaxEnt.
Fig 6.
The overall habitat suitability of Bactrocera zonata under current (A) and four future climate change scenarios [i.e. four representative concentration pathways (RCPs)]–RCPs 2.6 (B), RCPs 4.5 (C), RCPs 6.0 (D) and RCPs 8.0 (E). These were obtained by merging the normalised climatic suitability with normalised host availability. The overall habitat suitability classes were: (i) not suitable (≤ 0.15), (ii) low suitability (0.16–0.30), (iii) medium suitability (0.31–0.60) and (iv) high suitability (≥ 0.61). “The figure was generated using the QGIS 3.10.2 software (https://qgis.org)”.
Fig 7.
Predictions of the potential natural dispersal of Bactrocera zonata based on the simple spread model developed.
The model was run for current climatic conditions for one generation of Bactrocera zonata (about 46 days), it is known to have between 7 and 9 generations in a year [20]. “The figure was generated using the QGIS 3.10.2 software (https://qgis.org)”.