TY  - THES
T1  - Modeling the distribution of introduced Gambusia affinis (Baird & Girard, 1853)
A1  - Regidor, Jericho James
A2  - Flores, Mary Joyce L.
LA  - English
PP  - Cebu City, Cebu
PB  - Department of Biology and Environmental Science, College of Science, University of the Philippines Cebu
YR  - 2022
UL  - https://tuklas.up.edu.ph/Record/UP-8027390931312570086
AB  - Gambusia affinis (mosquitofish) has been introduced in waters globally as mosquito control but has since gained notoriety as one of the world's most invasive species. Studying its distribution then becomes vital as its unchecked distribution could lead to loss of biodiversity in sites of introduction. Ecological niche modeling studies of invasive mosquitofish are focused mostly in temperate regions which experience a different climate to tropical regions. This study focused on the distribution of mosquitofish in Southeast Asia, specifically the Philippines, and the environmental factors that limit its distribution in tropical countries. MaxEnt was used to build presence-background species distribution models using known occurrence points of mosquitofish from literature and GBIF, and Poeciliidae background species. Six environmental predictors were selected from WorldClim datasets at 2.5 min resolution. The MaxEnt model provided an AUC value of 0.723 and a Boyce index of 0.9207. The AUC and Boyce index values indicated a suitable prediction and the jackknife plots were used to identify the variable best fit for training data and the AUC. Precipitation during the coldest quarter (37.1% contribution), elevation (31.6% contribution), and temperature annual range (26.2% contribution) were found to be the variables responsible for predicting the distribution of mosquitofish in Southeast Asia. In the Philippines specifically, suitable habitats included the river basins Cagayan, Abra, Agno, Pampanga, Agus, Cagayan De Oro, Tagoloan, Davao, Agusan, Mindanao and Buayan-Malungon. The limiting factors of mosquitofish distribution being temperature related could imply a longer reproductive season, possibly increasing their population. Elevation is a factor in habitat suitability despite low temperature and flow as it creates low-flow channels for shelter. However, further studies on their life history and species interactions in tropical climates are needed to determine their effect on local ecosystems.
NO  - Thesis (Bachelor of Science in Biology). University of the Philippines Cebu. June 2022
CN  - LG 993 2022 B4 R44
ER  -