Predicting impact of climate change on habitat suitability of guava fruit fly, Bactrocera correcta (Bezzi) using MaxEnt modeling in India

Maximum entropy (MaxEnt) modeling was used to predict impact of climate change on habitat suitability of guava fruit fly, Bactrocera correcta in India. It is a polyphagus pest on a wide variety of fruit crops. Future prediction of potential habitat of B.correcta was done for the year 2050 and 2070 with RCP 2.6, RCP 4.5, RCP 6.0 and RCP 8.5 climate scenarios. The model preformed better than random with an average test AUC value of 0.75 of 100 replicate tests run. Under the present and future climatic conditions, the model predicted high habitat suitable category for B. correcta in the areas of south-western coastal (Kerala, Karnataka, Tamilnadu, Maharashtra and Gujarat) part of India by 2050 and 2070. Presently absolute unsuitable areas of Indian sub-continent are projected to be slightly suitable for B. correcta by 2070 due to increase in temperature coupled with decrease in cold stress. The predictive modeling approach presented here provides an outline for future risk of B.correcta in India under climate change scenarios, which can be used for its better management strategies.

Estimated Density, Population Size and Distribution of the Endangered Western Hoolock Gibbon (Hoolock hoolock) in Forest Remnants in Bangladesh

Tropical forests are threatened worldwide due to deforestation. In South and Southeast Asia, gibbons (Hylobatidae) are important to seed dispersal and forest regeneration. Most gibbons are threatened due to deforestation. We studied the western hoolock gibbon (Hoolock hoolock) in Bangladesh to determine population size and extent of suitable habitat. We used distance sampling to estimate density across 22 sites in northeastern and southeastern Bangladesh. We used Maxent modeling to determine areas of highly suitable habitat throughout Bangladesh. Density was estimated to be 0.39 ± 0.09groups/km2, and the total estimated population was 468.96 ± 45.56 individuals in 135.31 ± 2.23 groups. The Maxent model accurately predicted gibbon distribution. Vegetation cover, isothermality, annual precipitation, elevation and mean temperature of the warmest quarter influenced distribution. Two areas in the northeast and two areas in the southeast have high potential for gibbon conservation in Bangladesh. We also found significantly more gibbons in areas that had some level of official protection. Thus, we suggest careful evaluation, comprehensive surveys and restoration of habitats identified as suitable for gibbons. We recommend bringing specific sites in the northeastern and southeastern regions under protection to secure habitat for remaining gibbon populations.

The humid and thermal impact on distribution of Sea buckthorn fly (Rhagolethis batava Hering, 1958) in Mongolia

A total of 80 species in 1834 types of Tephritidae Newman (fruit flies) were recorded in the Mongolian-Russian comprehensive and joint expedition report, which was organized in 1967-1995. In the course of an itinerary survey conducted in 2019, we have recorded the dispersion of Rhagoletis batava at 223 natural (wild) and planted sea buckthorn points in 22 soums of Bayan-Ulgii, Uvs, Zavkhan, Khovd, Selenge and Govi-Altai aimags (provinces). Accordingly, we summarized the spread of sea buckthorn fruit fly relating mostly to territories that have dry and cooler climates, while some areas are humid and cold. Based on the dispersion points, we determined the current and future changes in the distribution of this species of flies, using the MaxEnt Modeling of geographical distribution. Thermal and humidity rates that affect the flies were estimated using data collected from 18 meteorological stations and sentinel posts. These points are located in different natural zones with an average annual air temperature fluctuating from -4.8 to 3.2°С. For example, in Tes soum of Uvs aimag, Bayantes soum of Zavkhan aimag and in Tes along the Tes river basin the average annual temperature is from -3.7 to - 4.8°С; in Baitag Kharuul of Bulgan soum of Khovd aimag, along the Bulgan river basin, the warmest temperature is 3.2°С, and in other soums it is -2.4 ... 1.8°С.

Predicting the geographic distribution habitats of Schizomyia buboniae (Diptera: Cecidomyiidae) and its host plant Deverra tortuosa (Apiaceae) in Egypt by using MaxEnt modeling

Background In some localities of the Mediterranean coast and the Nile land region, the gall midge Schizomyia buboniae Frauenfeld, 1859 (Diptera: Cecidomyiidae) induce small barrel-shaped galls on the stem of Deverra tortuosa (Desf.) DC. (Family: Apiaceae). Host plants interact with several insects in a different manner. The current work studies the interaction of S. buboniae with D. tortuosa. Furthermore, the present work predicted the distribution of S. buboniae and its host plant D. tortuosa in Egypt by using MaxEnt modeling, in addition to the effect of elevation and vegetation cover on its distribution. Results The predominance of S. buboniae occurred during late winter to spring. The S. buboniae larvae are occasionally attacked by endoparasitoids of the genus Inostemma (Platygastridae). There was a significant positive correlation between the number of galls per plant and the plant cover within the study localities. Meanwhile, there was no significant correlation between the number of galls per plant and the altitude within the study localities. Also, the high temperature and altitude were the most important predictors for the habitat distribution of S. buboniae and its host plant D. tortuosa. The predicted distribution range size for S. buboniae is less than the total predicted distribution range size for D. tortuosa. Conclusions The current study suggests that the gall inducer prefers large plants more than small ones. The present study suggests that the habitat distribution patterns of S. buboniae and its host plant D. tortuosa in Egypt can be modeled using a small number of occurrence records together with environmental variable layers for the study area through the maximum entropy modeling technique.

Maxent modeling for predicting the potential distribution of Arbutus andrachne L. belonging to climate change in Turkey.

Arbutus andrachne L., the strawberry tree, is an evergreen shrub or small tree in the Turkish flora and has broad uses. The wood is used for decorative purposes, packaging, and manufacturing furniture. The fruits are edible and used in treating many kinds of diseases. However, global warming might affect the abundance of this symbolic plant's distribution, especially at higher latitudes. This study was conducted to determine the expected effects of climate change on A. andrachne. For this purpose, Representative Concentration Pathway (RCP) 4.5 and RCP 8.5 were used to expect climate change scenarios for 2050 and 2070, and potential distribution areas of A. andrachne were presented. The results indicated that the distribution of A. andrachne would decrease in the southern regions of Turkey. However, the spread of the species could be expanded in the western and northern areas. It is also expected that there would be potential habitat losses, which would affect the distribution of A. andrachne.