Mapping Potential Midas Cichlid Spread for Invasive Population Control in Indonesian Waters

¹ School of Graduate Program, Department of Environmental Resource Management and Development, Universitas Brawijaya, Indonesia, 65145
² Department of Biology, Faculty of Mathematics and Natural Sciences, Universitas Brawijaya, Indonesia, 65145
³ Ichthyo-Fauna, Department of Fisheries, Faculty of Fisheries and Marine Science, Universitas Brawijaya, Indonesia, 65145

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract

A. citrinellus (Midas Cichlid) is an invasive fish species introduced to Indonesian waters through the ornamental fish trade. This species poses a serious threat to native fish populations through predation, competition, and habitat alteration. This study aims to determine priorities in the management and elimination of the Midas Cichlid in high-risk areas in Indonesian freshwater environments using species distribution modelling. The Maximum Entropy (MaxEnt) algorithm was used with 20 validated presence records and six bioclimatic variables (BIO 2, 4, 8, 15, 18, and 19), which were selected through Pearson correlation analysis and Variance Inflation Factor. Model performance was evaluated using the AUC (Area Under Curve) metric and jackknife analysis. The model showed remarkable predictive efficacy, with an average AUC value of 0.955 (SD = 0.017). Seasonal rainfall contributed 28%, followed by seasonal temperature 26.9% and cold quarter rainfall 24.2%. The optimum suitability zone is largely located in Java, Bali, Lombok, South Kalimantan, Central and Southeast Sulawesi, and several areas of Papua. These included important habitats for endemic and endangered species such as Betta burdigala, Chilatherina sentaniensis, and Oxyeleotris heterodon. The integrated implementation of population suppression techniques, including trade restrictions, habitat rehabilitation, and continuous monitoring are critical for reducing invasive populations.