Present and future habitat suitability of an endemic tree frog, Zhangixalus jarujini, under climate change scenario

Main Article Content

CHANTIP CHUAYNKERN
NUTTAPONG KHAJITMATHEE
RATCHATA PHOCHAYAVANICH
WASSANA MAIPHROM
EKACHAI PHETCHARAT
AINGORN CHAIYES
PRATEEP DUENGKAE
YODCHAIY CHUAYNKERN

Abstract

Abstract. Chuaynkern C, Khajitmathee N, Phochayavanich R, Maiphrom W, Phetcharat E, Chaiyes A, Duengkae P, Chuaynkern Y. 2025. Present and future habitat suitability of an endemic tree frog, Zhangixalus jarujini, under climate change scenario. Biodiversitas 26: 4445-4456. Zhangixalus jarujini, a tree frog in the family Rhacophoridae and endemic to northeastern Thailand, is increasingly threatened by habitat degradation and the impacts of climate change. This study utilized ecological niche modeling with the Maximum Entropy (MaxEnt) algorithm to evaluate the species’ current and future habitat suitability across Thailand, Laos, and Cambodia. A total of 16 confirmed occurrence records and 14 environmental variables were used to generate highly accurate models (mean AUC: 0.991±0.001). The most influential predictor variables were distance to water bodies (25.7%), precipitation seasonality (Bio15: 24.5%), precipitation of the warmest quarter (Bio18: 15.0%), normalized difference water index (NDWI: 13.3%), precipitation of the driest month (Bio14: 10.8%), and isothermality (Bio3: 9.2%). Under current conditions, the total area of suitable habitat was estimated at 9,964.58 km², comprising 5,837.82 km² of low suitability, 3,393.10 km² of medium suitability, and 733.67 km² of high suitability. Future projections, based on the ACCESS-CM2 climate model, were conducted under two Shared Socioeconomic Pathways: SSP2-4.5 and SSP5-8.5. By 2050, suitable habitat is projected to expand to 12,178.84 km² (22.22%) under SSP2-4.5 and 12,451.58 km² (24.96%) under SSP5-8.5. By 2070, it may reach 12,113.35 km² (21.56%) and 12,559.14 km² (26.44%) under the respective scenarios. High suitability areas are predicted to increase significantly, with a maximum of 1,228.58 km² under SSP5-8.5 by 2070, representing a 67.46% gain. The most influential environmental variables shaping habitat suitability were distance to water bodies, precipitation seasonality, and precipitation during the driest month. While these projections indicate a potential expansion of suitable habitat, actual population persistence may be constrained by ecological limitations, habitat fragmentation, and human pressures. Based on the model outputs and the availability of similar habitats in adjacent regions, this study strongly recommends systematic and intensive field surveys in Thailand, southern Laos, and northern Cambodia to identify potential undocumented populations and refine conservation priorities for Z. jarujini.

Article Details

Section

Articles

References

Araújo MB, Anderson RP, Barbosa AM. 2019. Standards for distribution models in biodiversity assessments. Sci Adv 5: eaat4858. DOI: 10.1126/sciadv.aat4858.

Booth TH. 2024. Forestry trials and species adaptability to climate change. Glob Change Biol 30: e17243. DOI: 10.1111/gcb.17243.

Booth TH. 2025. The origins of modern species distribution modelling: Some comments on the Vasconcelos et al. (2024) review. Earth 6 (1): 12. DOI:10.3390/earth6010012.

Button ST, Brown DJ, Piovia-Scott J. 2025. Amphibians reveal unexpectedly large differences in potential climate change responses among ecologically similar habitat specialists. Ecol Indic 174: 113488. DOI: 10.1016/j.ecolind.2025.113488.

Chuaynkern C, Duengkae P. 2014. Decline of amphibians in Thailand. In: Heatwole H, Das I (eds.). Conservation Biology of Amphibians of Asia. Status of Conservation and Decline of Amphibians: Eastern Hemisphere. National History Publications, Borneo.

Chuaynkern C, Khajitmathee N, Phochayavanich R, Phommexay P. 2025. Present and future habitat suitability of Mantheyus phuwuanensis under climate change scenario. Biodiversitas 26 (3): 1075-1084. DOI: 10.13057/biodiv/d260306.

Chuaynkern Y, Inthara C, Duengkae P, Songchan R. 2010. Geographic extension of Odorrana aureola Stuart, Chuaynkern, Chan-ard and Inger, 2006 in Thailand (Amphibia: Anura: Ranidae). Thailand Nat Hist Mus J 4: 29-33.

Chunco AJ, Phimmachak S, Sivongxay N, Stuart B. 2013. Predicting environmental suitability for a rare and threatened species (Lao newt, Laotriton laoensis) using validated species distribution models. Plos One 8: e59853. DOI: 10.1371/journal.pone.0059853.

Cobos ME, Peterson AT, Barve N, Osorio-Olvera L. 2019. Kuenm: An R package for detailed development of ecological niche models using Maxent. PeerJ 7: e6281. DOI: 10.7717/peerj.6281.

Deutsch CA, Tewksbury JJ, Huey RB, Sheldon KS, Ghalambor CK, Haak DC, Martin PR. 2008. Impacts of climate warming on terrestrial ectotherms across latitude. Proc Natl Acad Sci 105 (18): 6668-6672. DOI: 10.1073/pnas.0709472105.

Duan RY, Kong XQ, Huang MY, Varela S, Ji X. 2016. The potential effects of climate change on amphibian distribution, range fragmentation and turnover in China. PeerJ 4: e2185. DOI: 10.7717/peerj.2185.

Duong ND, Cam LV. 2021. 30-year changes of natural forests under human activities in the Indochina peninsula: Case studies in Cambodia, Laos and Vietnam. Sci Earth 43: 285-300. DOI: 10.15625/2615-9783/16196.

Elith J, Leathwick JR. 2009. Species distribution models: Ecological explanation and prediction across space and time. Annu Rev Ecol Evol Syst 40: 677-697. DOI: 10.1146/annurev.ecolsys.110308.120159.

Frost DR. 2025. Amphibian Species of the World: An Online Reference. Version 6.2. https://amphibiansoftheworld.amnh.org/index.php.

Fu Y, Lu J, Yang P, Pi J. 2025. Predictions of the Chinese forest frog (Rana chensinensis) distribution pattern under climate change up to 2090s. Biology 14 (7): 754. DOI: 10.3390/biology14070754.

Hardy BM, Muths E, Lambert BA, Schneider SC. 2023. Compensatory recruitment unlikely in high-elevation amphibian populations challenged with disease. J Appl Ecol 60: 121-131. DOI: 1 0.1111/1365-2664.14310.

Hausfather Z, Peters GP. 2020. Emissions-the ‘business as usual’ story is misleading. Nature 577: 618-620. DOI: 10.1038/d41586-020-00177-3.

IPBES. 2019. Summary for Policymakers of the Global Assessment Report on Biodiversity and Ecosystem Services of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. IPBES, Bonn, Germany.

IPCC. 2021. Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change. IPCC, Switzerland.

IUCN. 2025. The IUCN Red List of Threatened Species. Version 2025-1. https://www.iucnredlist.org.

Jiang D, Jiang K, Ren J, Wu J, Li J. 2019. Resurrection of the genus Leptomantis, with description of a new genus to the family Rhacophoridae (Amphibia: Anura). Asian Herpetol Res 10: 1-12.

Kaewtongkum N, Chuaynkern C, Thongproh P, Chuaynkern Y. 2014. Buccal description of Rhacophorus jarujini Matsui and Panha, 2006 from northeastern Thailand. Proceedings of 40th Congress on Science and Technology of Thailand. Khon Kaen, Thailand, 2-4 December 2014.

Khajitmathee N, Kaewtongkum N, Chaiyes A, Suksavate W. 2025. Current distribution and habitat suitability for the present and future scenarios of Cyrtodactylus angularis in Thailand. Biodiversitas 26 (3): 1039-1050. DOI: 10.13057/biodiv/d260302.

Laurence F, Nicolas V, Ayoro HJ, Ohler A. 2023. Species distribution modelling of Hylarana species (Anura, Ranidae) and the problem of accurate species identification. Zootaxa 5258: 99-112. DOI: 10.11646/zootaxa.5258.1.4.

Lenzi O, Grossenbacher K, Zumbach S, Lüscher B. 2024. Interplay of abiotic conditions, density, and body size in shaping demography in a high-elevation toad population. Ecosphere 15: e70048. DOI: 10.1002/ecs2.70048.

Mahony S, Kamei RG, Brown RM, Chan KO. 2024. Unnecessary splitting of genus-level clades reduces taxonomic stability in amphibians. Vertebr Zool 74: 249-277. DOI: 10.3897/vz.74.e114285.

Makchai S, Chuaynkern Y, Chuechat C, Cota M. 2023. Amphibians of Northeastern Thailand. Thailand Natural History Museum, National Science Museum, Pathum Thani.

Matsui M, Panha S. 2006. A new species of Rhacophorus from eastern Thailand (Anura: Rhacophoridae). Zool Sci 23: 477-481. DOI: 10.2108/zsj.23.477.

Moonasa B, Thongproh P, Phetcharat E. 2018. The stomach contents of some anuran tadpoles from Thailand. J Wildl Thail 25: 21-39.

Nandar H, Li LL, Oo ZM, Lwin YH, Quan RC. 2025. Younger semi-captive Asian elephants constitute suitable repository for conservation translocation. Conserv Sci Pract 7: e70041. DOI: 10.1111/csp2.70041.

Niyomwan P, Srisom P, Pawangkhanant P. 2019. Amphibians of Thailand. Parbpim, Bangkok. [Thai]

Office of Natural Resources and Environmental Policy and Planning. 2017. Thailand Red Data: Vertebrates. Ministry of Natural Resources and Environment, Bangkok.

Peterson AT, Cobos ME, Jiménez-García D. 2018. Major challenges for correlational ecological niche model projections to future climate conditions. Ann N Y Acad Sci 1429: 66-77. DOI: 10.1111/nyas.13873.

Phimmachak S, Richards SJ, Sivongxay N, Seateun S. 2019. A new caruncle-bearing fanged frog (Limnonectes, Dicroglossidae) from Laos and Thailand. ZooKeys 846: 133-156. DOI: 10.3897/zookeys.846.33200.

Phommexay P, Chaiyes A, Duengkae P, Chuaynkern C, Chuaynkern Y. 2024a. Current and suitable habitat of the Critically endangered northern white-cheeked gibbon (Nomascus leucogenys) in Lao PDR. Ecol Monten 75: 103-118. DOI: 10.37828/em.2024.75.10.

Phommexay P, Chaiyes A, Duengkae P, Chuaynkern C, Chuaynkern Y. 2024b. Estimation of population and threats of the northern white-cheeked gibbon (Nomascus leucogenys) in Phou Khao Khouay National Biodiversity Conservation Area, Lao PDR. Agri Nat Resour 58 (4): 453-462. DOI: 10.34044/j.anres.2024.58.4.05.

Pomoim N, Hughes AC, Trisurat Y, Corlett RT. 2022. Vulnerability to climate change of species in protected areas in Thailand. Sci Rep 12: 5705. DOI: 10.1038/s41598-022-09767-9.

Poyarkov NA Jr, Nguyen TV, Popov ES, Geissler P. 2021. Recent progress in taxonomic studies, biogeographic analysis, and revised checklist of amphibians of Indochina. Russ J Herpetol 28: 1-110. DOI: 10.30906/1026-2296-2021-28-3A-1-110.

Prakash S, Verma AK. 2022. Anthropogenic activities and biodiversity threats. Intl J Biol Innov 4: 94-103. DOI: 10.46505/IJBI.2022.4110.

Prayoon U, Suksavate W, Chaiyes A. 2021. Past, present and future habitat suitable for gaur (Bos gaurus) in Thailand. Agri Nat Resour 55 (5): 743-756. DOI: 10.34044/j.anres.2021.55.5.05.

Roy S, Suman A, Ray S, Saikia SK. 2022. Use of species distribution models to study habitat suitability for sustainable management and conservation in the Indian subcontinent: A decade's retrospective. Front Sustain Resour Manag 1: 1031646. DOI: 10.3389/fsrma.2022.1031646.

Shrestha N. 2020. Detecting multicollinearity in regression analysis. Am J Appl MathStat 8: 39-42. DOI: 10.12691/ajams-8-2-1.

Sillero N, Barbosa AM. 2021. Common mistakes in ecological niche models. Intl J Geogr Inf Sci 35: 213-226. DOI: 10.1080/13658816.2020.1798968.

Stuart BL, Chuaynkern Y, Chan-ard T, Inger RF. 2006. Three new species of frogs and a new tadpole from eastern Thailand. Fieldiana Zool 111: 1-19. DOI: 10.3158/0015-0754(2006)187[1:TNSOFA]2.0.CO;2.

Thongproh P, Duengkae P, Ratree P. 2019. Species diversity and prey items of amphibians in Yoddom Wildlife Sanctuary, northeastern Thailand. Biodiversitas 20 (9): 2718-2732. DOI: 10.13057/biodiv/d200937.

Thongproh P, Youjaroen M, Chuaynkern Y. 2018. On the identities of Rhacophorus jarujini Matsui and Panha, 2006 and Rhacophorus orlovi Ziegler and Köhler, 2001 (Amphibia, Anura, Rhacophoridae) from Thailand. Maejo Intl J Sci Technol 12: 36-50.

Tran DV, Hoang TT, Nguyen TH. 2023. Current and future suitable habitats of a range-restricted species group (Cyrtodactylus chauquangensis) in Vietnam. Raffles Bull Zool 71: 224-236. DOI: 10.26107/RBZ-2023-0017.

Urban MC. 2015. Accelerating extinction risk from climate change. Science 348: 571-573. DOI: 10.1126/science.aaa4984.

Van Proosdij ASJ, Sosef MSM, Wieringa JJ, Raes N. 2016. Minimum required number of specimen records to develop accurate species distribution models. Ecography 39: 542-552. DOI: 10.1111/ecog.01509.

Warren R, Price J, Van Der Wal J. 2018. The implications of the United Nations Paris Agreement on climate change for globally significant biodiversity areas. Clim Change 147: 395-409. DOI: 10.1007/s10584-018-2158-6.

Wild Animal Conservation and Protection Act. 2019. Wild Animal Conservation and Protected Act, B.E. 2562 (2019). FAO, Rome.

Wilson MFJ, O’Connell B, Brown C, Guinan JC, Grehan AJ. 2007. Multiscale terrain analysis of multibeam bathymetry data for habitat mapping on the continental slope. Mar Geod 30: 3-35. DOI: 10.1080/01490410701295962.

Zhao T, Khatiwada JR, Zhao C, Feng J, Sun Z. 2022. Elevation patterns of amphibian functional and phylogenetic structures in eastern Nepal Himalaya. Divers Distrib 28: 2475-2488. DOI: 10.1111/ddi.13593.

Most read articles by the same author(s)

1 2 > >>