Predicting the Potential Distribution Areas of the Asian Redtail Catfish (Hemibagrus wyckioides Fang and Chaux, 1949) in the Chao Phraya River, Thailand, using Maximum Entropy Modelling

Hemibagrus wyckioides is recognized as an economically important freshwater fish in Thailand. However, there are no available comprehensive data regarding the geographic distribution and habitat suitability of H. wyckioides in Thailand. In addition, its natural population has tended to continuously decrease. This study aimed to predict the suitable distribution areas of H. wyckioides in the Chao Phraya River, Thailand, using the maximum entropy (MaxEnt) algorithm based on climatic factors, including 11 temperature and 8 precipitation indices from the WorldClim database. Model performance was evaluated by the area under the receiver operating characteristic curve (AUC). The jackknife test was used to assess the contribution of each variable to the model. The results revealed that the MaxEnt model performed acceptably well, with an AUC value of 0.939, representing excellent accuracy in predicting the appropriate distribution areas of H. wyckioides in the Chao Phraya River. The potential distribution areas of H. wyckioides were observed mostly along the Chao Phraya River in Sing Buri and Ang Thong Provinces. According to the results of the jackknife test, 11 climatic variables impacted the distribution of H. wyckioides. The annual mean temperature (BIO1), precipitation of driest month (BIO14), and annual temperature range (BIO7) were the most important influencing variables, with impact values of 53.5%, 15.9%, and 11.9%, respectively. Therefore, understanding the potential distribution areas can assist researchers in monitoring, management, and conservation activities or with the development of new natural protected areas of H. wyckioidesin high-quality areas in the Chao Phraya River.