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The teak bee‐hole borer (Xyleutes ceramica (Walker, 1865)) is widespread in northern Thailand and is considered the most serious pest of teak (Tectona grandis) in the country. The present study investigated the factors affecting the infestation of teak trees by this species in three plantations in northern Thailand at different spatial scales, including the tree, plot and stand levels. At each plantation, 48 plots evenly distributed in three different young stands (1–10 years), three medium‐aged stands (11–20 years) and six old stands (exceeding 20 years) were sampled. At the plots, the number of current entrance holes of X. ceramica per teak tree was counted, and the characteristics of the trees and stands were assessed. A total of 1952 teak trees were sampled, 22.7% of which were infested by X. ceramica. According to our results, infestation was much more strongly affected by stand characteristics than by the characteristics of individual trees. Above all, understorey cover exhibited substantial effect with the infestation level being strongly limited in stands with dense understories. Additionally, young and medium‐aged stands on better quality sites were found to be the most susceptible to infestation, and well‐growing and/or damaged trees were preferred by the pest species. In conclusion, major recommendations for suppressing damage caused by X. ceramica include (a) promoting and maintaining the understorey above 30% cover, (b) planting mixed stands of commercial forest trees and (c) intensively monitoring the pest in young and medium‐aged stands, especially those growing at good‐ and medium‐quality sites. [ABSTRACT FROM AUTHOR]

Banteng (Bos javanicus) is listed as an endangered species because of a global population decline of at least 50% over the last 25 years. The Western Forest Complex (WEFCOM) of Thailand has been identified as a priority site for banteng population recovery, and Huai Kha Keang Wildlife Sanctuary (HKK) is the most important source site for this species within the WEFCOM. We have provided evidence and discussed banteng dispersal from HKK to Thung Yai Naresuan West Wildlife Sanctuary (TYW). We sampled an area of 147 km2 in banteng habitat next to the border between HKK and TYW using camera traps. We divided the sampled area into four grid cells and placed camera traps during January to December 2022. We setup the camera traps near saltlicks and natural water sources, as important resources for banteng, to maximize capture probability. In total, 2835 trap days were obtained. Bantengs were captured in all seasons (RAI = 1.66), especially in dry dipterocarp forest, which contains the ground forage availability for banteng, and the low‐slope area with elevation 600–700 m adjacent to the border between HKK and TYW. The results highlighted that banteng, which had never been reported in TYW before, appeared there for the first time. They most likely dispersed from the population source in HKK and settled in a habitat that is considered suitable for them. The habitat management and protection are significant for the future recovery of banteng populations in the TYW and the rest of protected areas in the WEFCOM. [ABSTRACT FROM AUTHOR]

The association between patch metrics and roosting site (n = 31) suitability of Lyle’s flying fox (Pteropus lylei) in 26 Central Eastern and Western provinces of Thailand was quantified. Land use classes with 90-m resolution were identified based on various vegetation and land cover types to calculate patch metrics using FRAGSTATS. Then, Maximum Entropy Modeling (MaxEnt) was performed using patch metrics covariates to produce a predictive potential distribution map. The results indicated that patch contiguity (contiguity index, 63.7%), patch area (29.3%), and patch shape complexity (shape index, 5.7%) are the most influential patch metrics, all of which have negative effects on roosting site suitability. In total, 13,222 small patches were considered highly suitable patches, with a mean area of 0.921 ± 0.698 (SD) ha, which accounted for 122,090 ha (2.04%) of the study area. Roosting sites predicted from the model were consistently associated with occurrences of roosting sites observed in temples; such habitats likely provide shelter from external threats for colonies roosting in a human-dominated landscape.

A Bayesian approach was used to develop binary quantile regression models featuring the lasso penalty. The models afford the advantages of all quantile regression models, such as robustness and detailed insights into covariate effects; they also handle issues associated with overfitting well. Thus, this model was used to investigate habitat suitability for the management of tiger prey species. Field data were collected from 150 sampling sites (2,416 sub-plots) in Thap Lan National Park of the Dong Phayayen-Khao Yai Forest Complex (DPKY) from August 2019 to March 2021. We focused on sambar deer (Rusa unicolor) and gaur (Bos gaurus) because they are the principal prey species of tigers. Vegetation was sampled for biomass and nutrient content to identify suitable habitat. The "bayesQR" package of R was used to identify habitats appropriate for these species. The correlation between forage crop biomass and the normalized difference vegetation index (NDVI) was significantly associated with tiger prey species presence. The habitat can be improved by increasing grass and forb biomasses as the prey species prefer open habitats, such as grassland and open areas of dry evergreen forest. Habitat management has ensured that the grass biomass of open forest is significantly higher than that of dense forest. In addition, the hemicellulose content of open forest was significantly greater than that of dense forest. We found that spatial modeling combined with Bayesian, lasso binary quantile regression could aid wildlife habitat management in a Thai National Park. [ABSTRACT FROM AUTHOR]

Understanding distribution patterns is essential for the long- term conservation of megafauna, particularly the Asian elephant (Elephas maximus). We investigated the dynamic occupancy of Asian elephants in the Thung Yai Naresuan West Wildlife Sanctuary in Thailand. Asian elephant occurrences were recorded during patrol activities from 2012 to 2019. We applied a single-species dynamic occupancy model to examine the environmental factors influencing habitat occupancy of Asian elephant across multiple seasons. The best- supported model, based on the Akaike information criterion (AIC), indicated that the normalized difference vegetation index and elevation positively influenced the probability of colonization. In contrast, the distance to the nearest population source sites showed a negative association. The probability of local extinction was positively correlated with the distance to the nearest villages and population source sites. The predictive map indicated a higher probability of colonization in a remote mountainous region of the center of the protected area. Higher extinction probability was associated with areas of dense human activity and far from population source sites connecting the Asian elephant population to the east. This is the first study to utilize a patrol database for assessing the dynamic occupancy of Asian elephants across multiple years. Our model provides insight into the dynamic distribution patterns of Asian elephants within the wildlife sanctuary and the factors that most influence these patterns. Long-term ecological data provide crucial information for assessing biodiversity, population status, and the ecological processes of focal wildlife species and are valuable for both protected area management and conservation efforts. [ABSTRACT FROM AUTHOR]

Teak is an important and valuable tropical hardwood species. In this study, we developed and evaluated suitable taper equations for teak growing in Western Thailand using a formulation of Goodwin cubic polynomial model combined with a bark thickness model. The best taper model calibration was selected based on goodness-of-fit and leave-one-out cross validation statistical testing. In total, 12 different model calibrations were tested, with Thong Pha Phum (TPP) 2 being the most suitable for teak in Western Thailand. The mean prediction error of three validation statistics: (prediction of diameter under bark given height; prediction of height given diameter under bark; and prediction of under bark volume given log length) were within 10% and the overall validation index was 5.454, which was the lowest when compared to other calibrations. A comparison of TPP 2 with a teak taper equation developed for Northern Thailand, using a graphical analysis of the stem shape and bark thickness, indicated that the teak trees growing in the two regions have similar stem shapes, but the trees in Western Thailand tend to have a thicker bark. These results will also help in further work as they indicate that bark thickness equations are particularly important. [ABSTRACT FROM AUTHOR]

Spatial modeling is an analytical procedure that simulates real-world conditions using remote sensing and geographic information systems. The field data in this study were collected from 318 survey plots in the area surrounding highway 304 in the Dong Phayayen-Khao Yai Forest Complex (DPKY-FC) during the 2019 rainy season. Forage-crop biomass was collected from all plots. We focused on sambar deer (Rusa unicolor) and gaur (Bos gaurus), which are the main prey for tigers in this area. We created spatial models using generalized linear models with stepwise regression. The results indicated that the normalized difference vegetation index (NDVI) varied directly with grass biomass but inversely with shrub biomass (p<0.05). Elevation varied directly with forb biomass but inversely with shrub biomass (p<0.05). The probability of occurrence of sambar deer varied directly with distance from disturbance variables, distance from the stream, and grass biomass (p<0.001), but inversely with NDVI (p<0.05). The occurrence of gaur varied directly with NDVI (p=0.08), but varied inversely with slope, distance from the road, and distance from the stream (p<0.05). Our results demonstrate that spatial modeling can be an effective tool for wildlife habitat management in the area surrounding highway 304. [ABSTRACT FROM AUTHOR]

The association between environmental factors and Engelmann spruce mortality in western Colorado was investigated using Bayesian hierarchical zero‐and‐one inflated beta regressive model. The results indicated that the probability of mortality occurrence rate was positively associated with moderate to warm temperature zones, moderate precipitation, and single canopy stands with the smaller size class of spruce within stands. The probability of full mortality rate was positively associated with warm and humid climate zones with spruce as subdominant species in the vertically complex stands. On the other hand, higher mortality rate was more associated with local stand characteristics than climate factors that low mortality rate associated with stands dominated by spruce of a large size classes. The correlation model offers an approach to create predicted risk map for probability and rate of spruce mortality that could help manager in precedent planning for the upcoming outbreak events. Recommendations for Resource ManagersThis study aims to investigate the environmental association of spruce bark beetle caused mortality in landscape context with binomial‐beta hierarchical framework.Both regional‐scale climate and stand‐level characteristics should be considered to assess the risk and severity of outbreak caused mortality at a large spatial scale.The mortality risk is higher and more severe in warmer zones, especially the stands with spruce as subdominant tree species should be more concerned.Predicted map could improve the ability to spatially assess the risk of spruce mortality assisting managers to be better prepared for the future outbreaks, particularly in the risky area. [ABSTRACT FROM AUTHOR]

The North African catfish (Clarias gariepinus) is a significant species in aquaculture, which is crucial for ensuring food and nutrition security. Their high adaptability to diverse environments has led to an increase in the number of farms that are available for their production. However, long-term closed breeding adversely affects their reproductive performance, leading to a decrease in production efficiency. This is possibly caused by inbreeding depression. To investigate the root cause of this issue, the genetic diversity of captive North African catfish populations was assessed in this study. Microsatellite genotyping and mitochondrial DNA D-loop sequencing were applied to 136 catfish specimens, collected from three populations captured for breeding in Thailand. Interestingly, extremely low inbreeding coefficients were obtained within each population, and distinct genetic diversity was observed among the three populations, indicating that their genetic origins are markedly different. This suggests that outbreeding depression by genetic admixture among currently captured populations of different origins may account for the low productivity of the North African catfish in Thailand. Genetic improvement of the North African catfish populations is required by introducing new populations whose origins are clearly known. This strategy should be systematically integrated into breeding programs to establish an ideal founder stock for selective breeding., Competing Interests: The authors declare no competing financial interests or personal relationships that have influenced this study., (Copyright: © 2024 Patta et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)