Vol. 20 No. 2 (2025)
Articles

Characterization of suitable breeding sites for Asiatic toads (Bufo gargarizans Cantor, 1842) (Anura, Bufonidae) using ecological modeling

Seung-Min Park
Department of Biological Sciences, Chonnam National University, 61186 Gwangju, Republic of Korea
Seung-Ju Cheon
School of Biological Sciences and Biotechnology, Chonnam National University, 61186 Gwangju, Republic of Korea
Choong-Ho Ham
School of Biological Sciences and Biotechnology, Chonnam National University, 61186 Gwangju, Republic of Korea
Su-Wan Park
Gwangyang Greenkorea, 57756, Gwangyang, Republic of Korea
Ha-Cheol Sung
Department of Biological Sciences, Chonnam National University, 61186 Gwangju, Republic of Korea

Published 2025-09-02

Keywords

  • GLM,
  • AIC,
  • conservation management,
  • shoreline depth,
  • barren,
  • water body
  • ...More
    Less

How to Cite

Park, S.-M., Cheon, S.-J., Ham, C.-H., Park, S.-W., & Sung, H.-C. (2025). Characterization of suitable breeding sites for Asiatic toads (Bufo gargarizans Cantor, 1842) (Anura, Bufonidae) using ecological modeling. Acta Herpetologica, 20(2), 211–219. https://doi.org/10.36253/a_h-17271

Abstract

Efforts to protect amphibian habitats and breeding sites are increasing, with ecological modeling playing a key role in predicting suitable habitats and informing conservation strategies. The Asiatic toad (Bufo gargarizans) is widely distributed across South Korea and is ideal for establishing comprehensive conservation measures. However, it is increasingly vulnerable to human activities and climate change. In this study, we investigated the breeding site characteristics of B. gargarizans using a generalized linear model (GLM). Field surveys were conducted at 124 reservoirs across three study sites at similar longitudes but different latitudes (Paju, Cheongju, and Gwangyang). To develop 30 candidate GLMs, using model selection based on the Akaike Information Criterion (AIC), 17 variables were collected from field measurements and geographic data. The results identified six factors influencing the suitability of B. gargarizans breeding sites: water temperature, dissolved oxygen, the average water depth 1 m from the shoreline, reservoir area, percentage of barren land within a 1km buffer, and percentage of water within a 1km buffer. The model indicated that areas with a shoreline depth of around 48 cm, low surrounding barren ratios (3%), and more than 3% water bodies are suitable for B. gargarizans breeding. These findings provide valuable insights into the conservation of B. gargarizans and can support the development of effective habitat protection measures.

References

  1. Alford, R.A., Richards, S.J. (1999): Global amphibian declines: A problem in applied ecology. Annu. Rev. Ecol. Syst. 30: 133-165.
  2. Banks, B., Beebee, T.J. (1987): Factors influencing breeding site choice by the pioneering amphibian Bufo calamita. Ecography. 10: 14-21.
  3. Beebee, T.J. (1997): Changes in dewpond numbers and amphibian diversity over 20 years on chalk downland in Sussex, England. Biol. Conserv. 81: 215-219.
  4. Blank, L., Blaustein, L. (2012): Using ecological niche modeling to predict the distributions of two endangered amphibian species in aquatic breeding sites. Hydrobiologia 693: 157-167.
  5. Borzée, A., Heo, K., Jang, Y. (2018): Relationship between agro-environmental variables and breeding Hylids in rice paddies. Sci. Rep. 8: 8049.
  6. Burnham, K.P., Anderson, D.R. (2004): Multimodel inference: Understanding AIC and BIC in model selection. SMR 33: 261-304.
  7. Crossland, M.R., Alford, R.A. (1998): Evaluation of the toxicity of eggs, hatchlings and tadpoles of the introduced toad Bufo marinus (Anura: Bufonidae) to native Australian aquatic predators. Aust. J. Ecol. 23: 129-137.
  8. Crump, M.L. (1991): Choice of oviposition site and egg load assessment by a treefrog. Herpetol. 47: 308-315.
  9. Cunningham, J.M., Calhoun, A.J., Glanz, W.E. (2007): Pond‐breeding amphibian species richness and habitat selection in a beaver‐modified landscape. J. Wildl. Manag. 71: 2517-2526.
  10. Decena, S.C.P., Avorque, C.A., Decena, I.C.P., Asis, P.D., Pacle, B. (2020): Impact of habitat alteration on amphibian diversity and species composition in a lowland tropical rainforest in Northeastern Leyte, Philippines. Sci. Rep. 10: 10547.
  11. Diniz‐Filho, J.A.F., Rangel, T.F.L., Bini, L.M. (2008): Model selection and information theory in geographical ecology. Glob. Ecol. Biogeogr. 17: 479-488.
  12. Dixo, M., Metzger, J.P., Morgante, J.S., Zamudio, K.R. (2009): Habitat fragmentation reduces genetic diversity and connectivity among toad populations in the Brazilian Atlantic Coastal Forest. Biol. Conserv. 142: 1560-1569.
  13. Durso, A.M., Willson, J.D., Winne, C.T. (2011): Needles in haystacks: Estimating detection probability and occupancy of rare and cryptic snakes. Biol. Conserv. 144: 1508-1515.
  14. Edgerly, J.S., McFarland, M., Morgan, P., Livdahl, T. (1998): A seasonal shift in egg‐laying behaviour in response to cues of future competition in a treehole mosquito. J. Anim. Ecol. 67: 805-818.
  15. Environmental Geographic Information Service (EGIS). (2019): Land cover map Subdivision. Sejong, South Korea. URL: https://egis.me.go.kr/intro/land.do/ Accessed 20 September 2024.
  16. Evans, M., Yáber, C., Hero, J.M. (1996): Factors influencing choice of breeding site by Bufo marinus in its natural habitat. Copeia 1996: 904-912.
  17. Fleishman, E., Murphy, D.D., Sjögren-Gulve, P. (2002): Modeling species richness and habitat suitability for taxa of conservation interest. In: Predicting Species Occurrences: Issues of Accuracy and Scale, pp. 506–517. Scott, J.M., Heglund, P.J., Morrison, M.L., Eds, Washington, DC, Island Press.
  18. Guisan, A., Zimmermann, N.E. (2000): Predictive habitat distribution models in ecology. Ecol. Model. 135: 147-186.
  19. Hirzel, A.H., Hausser, J., Chessel, D., Perrin, N. (2002): Ecological‐niche factor analysis: How to compute habitat‐suitability maps without absence data?. Ecol. 83: 2027-2036.
  20. Hu, S. (2007): Akaike information criterion. CRSC 93: 1-20.
  21. International Union for Conservation of Nature (IUCN): (2022): Bufo gargarizans. IUCN red list Threatened Species. Cambridge, UK. URL: https://www.iucnredlist.org/species/78017839/197248539/ Accessed 20 September 2024.
  22. Jeong, J.S. (2017): On the population density of Bufo bufo gargarizans in the wetland of nearby Seomjin river and its habitats. Master’s Theses. Kong Ju National University, Kong Ju.
  23. Johnson, J.B., Omland, K.S. (2004): Model selection in ecology and evolution. TREE. 19: 101-108.
  24. Jowers, M.J., Downie, J.R. (2005): Tadpole deposition behaviour in male stream frogs Mannophryne trinitatis (Anura: Dendrobatidae). J. Nat. Hist. 39: 3013-3027.
  25. Kiesecker, J.M., Chivers, D.P., Blaustein, A.R. (1996): The use of chemical cues in predator recognition by western toad tadpoles. Anim. Behav. 52: 1237-1245.
  26. Kruse, K.C., Stone, B.M. (1984): Largemouth bass (Micropterus salmoides) learn to avoid feeding on toad (Bufo) tadpoles. Anim. Behav. 32: 1035-1039.
  27. Lee, J.H., Jang, H.J., Seo, J.H. (2011): Ecological guide book of herpetofauna in Korea, pp. 64-66. Incheon, Republic of Korea. National Institute of Environmental Research.
  28. Lee, S.H. (2003): A comparative histological study on some salientia inhabitated in Korea. Gwangju, Honam University Academic papers 24: 289-303.
  29. Lim, M.A., Choi, W.K., Eo, S.H., Choi, H.Y., Lee, J.S., Yang, W.K., Woo, S.H., Park, Y.S. (2005): Detection of bufotoxins in toad venom and toad eggs. Kor. J. Forensic Sci. 6: 125-130.
  30. Lin, Y.S., Lehtinen, R.M., Kam, Y.C. (2008): Time-and context-dependent oviposition site selection of a phytotelm-breeding frog in relation to habitat characteristics and conspecific cues. Herpetol. 64: 413-421.
  31. Lunghi, E., Manenti, R., Ficetola, G.F. (2015): Seasonal variation in microhabitat of salamanders: Environmental variation or shift of habitat selection? PeerJ 3: e1122.
  32. Luo, Z., Hu, M., Hong, M., Li, C., Gu, Q., Gu, Z., Liao, C., Zhao, M., Wu, H. (2015): Outbreeding avoidance as probable driver of mate choice in the Asiatic toad. J. Zool. 295: 223-231.
  33. Luo, Z., Li, C., Wang, H., Zhao, M., Gu, Q., Gu, Z., Liao, C., Wu, H. (2014): Mutual mate choice in the Asiatic toad, Bufo gargarizans, exerts stabilizing selection on body size. Chin. Sci. Bull. 59: 38-45.
  34. MacKenzie, D.I., Bailey, L.L. (2004): Assessing the fit of site-occupancy models. JABES 9: 300-318.
  35. Matushkina, K.A., Makarov, O., Afrin, K., Kidov, A., Litvinchuk, S. (2022): Patterns of reproduction, growth and development in Asiatic toads, (Bufo gargarizans Cantor, 1842) from Russia and China: An experimental comparison. Herpetol. Notes. 15: 123-138.
  36. Murphy, P.J. (2003a): Does reproductive site choice in a neotropical frog mirror variable risks facing offspring?. Ecol. Monogr. 73: 45-67.
  37. Murphy, P.J. (2003b). Context-dependent reproductive site choice in a Neotropical frog. Behav. Ecol. 14: 626-633.
  38. National Institute of Ecology (NIE). (2018): The 4th National Natural Environment Survey Amphibians and Reptiles. National Institute of Ecology. Seocheon, Republic of Korea.
  39. Newman, R.A. (1988): Adaptive plasticity in development of Scaphiopus couchii tadpoles in desert ponds. Evol. 42: 774-783.
  40. Noland, R., Ultsch, G.R. (1981): The roles of temperature and dissolved oxygen in microhabitat selection by the tadpoles of a frog (Rana pipiens) and a toad (Bufo terrestris). Copeia 1981: 645-652.
  41. Othman, S.N., Litvinchuk, S.N., Maslova, I., Dahn, H., Messenger, K.R., Andersen, D., Jowers, M.J., Kojima, Y., Skorinov, D.V., Yasumiba, K., Chuang, M., Chen, Y., Bae, Y., Hoti, J., Jang, Y., Borzee, A. (2022): From Gondwana to the Yellow Sea, evolutionary diversifications of true toads Bufo sp. in the Eastern Palearctic and a revisit of species boundaries for Asian lineages. Elife. 11: e70494.
  42. Park, S.M., Kang, H.J., Ham, C.H., Lee, J.E., Park, S.W., Sung, H.C. (2021): A case study of the movement and behavior of Asian toads (Bufo gargarizans) during post-breeding season in the spring. Korean J. Herpetol. 12: 9-15.
  43. Park, S.M., Rahman, M.M., Ham, C.H., Park, S.W., Kang, H.J., Sung, H.C. (2025): Movement patterns and habitat use within the home range of the Asiatic toad (Bufo gargarizans) prior to hibernation. Herpetozoa. 38: 77-85.
  44. Park, S.M., Rahman, M.M., Park, H.R., Cheon, S.J., Kang, H.J., Park, S.W., Ham, C.H., Sung, H.C. (2024): Resting site selection and microhabitat use of an Asiatic toad (Bufo gargarizans; Anura: Amphibia) in South Korea. Curr. Herpetol. 43: 203-213.
  45. Pearl, C.A., Adams, M.J., Leuthold, N., Bury, R.B. (2005): Amphibian occurrence and aquatic invaders in a changing landscape: Implications for wetland mitigation in the Willamette Valley, Oregon, USA. Wetlands 25: 76-88.
  46. Ra, N.Y., Park, D., Cheong, S., Kim, N.S., Sung, H.C. (2010): Habitat associations of the endangered gold-spotted pond frog (Rana chosenica). Zool. Sci. 27: 396-401.
  47. Resetarits Jr, W.J., Wilbur, H.M. (1989): Choice of oviposition site by Hyla chrysoscelis: Role of predators and competitors. Ecol. 70: 220-228.
  48. Rudolf, V.H., Rödel, M.O. (2005): Oviposition site selection in a complex and variable environment: The role of habitat quality and conspecific cues. Oecologia 142: 316-325.
  49. Semeniuk, M., Lemckert, F., Shine, R. (2007): Breeding-site selection by cane toads (Bufo marinus) and native frogs in northern New South Wales, Australia. Wildl. Res. 34: 59-66.
  50. Semlitsch, R.D. (2000): Principles for management of aquatic-breeding amphibians. J. Wildl Manage. 64: 615-631.
  51. Skelly, D.K., Werner, E.E., Cortwright, S.A. (1999): Long‐term distributional dynamics of a Michigan amphibian assemblage. Ecology. 80: 2326-2337.
  52. Smith, D.C. (1983): Factors controlling tadpole populations of the chorus frog (Pseudacris triseriata) on Isle Royale, Michigan. Ecol. 64: 501-510.
  53. Spieler, M., Linsenmair, K.E. (1997): Choice of optimal oviposition sites by Hoplobatrachus occipitalis (Anura: Ranidae) in an unpredictable and patchy environment. Oecologia 109: 184-199.
  54. Stebbins, R.C., Cohen, N.W. (2021): A natural history of amphibians. Princeton University Press, Princeton, New Jersey.
  55. Su, J., Han, M., Zhu, X., Liao, C., Tu, S., Luo, Z. (2020): Habitat selection of the Asiatic toad (Bufo gargarizans) during hibernation in the Badagongshan National Nature Reserve, central China. Salamandra 56: 16-26.
  56. Sung, H.C., Park, O.H., Kim, S.K., Park, D.S., Park, S.R. (2007): Abundance and breeding migration of the Asian toad (Bufo gargarizans). J Ecol Environ 30: 287-292.
  57. Yang, L., Huang, L., Zhang, H., Lee, P., Zhang, N., Cai, R., Li, E., Pan, T., Wu, X. (2023): Habitat suitability and distribution pattern response to global climate change in a widespread species, the Asiatic toad (Bufo Gargarizans). AHR 14:138-146.
  58. Yang, L., Zhang, H., Zhang, N., Cai, R., Yan, P., Li, E., Pan, T., Wu, X. (2020): Population and habitat responses to the global climate change in a widespread species, the Asiatic toad (Bufo gargarizans). Authorea Preprints.
  59. Yu, T.L., Gu, Y.S., Du, J., Lu, X. (2009): Seasonal variation and ontogenetic change in the diet of a population of Bufo gargarizans from the farmland, Sichuan, China. Biharean Biol. 3: 99-104.
  60. Yu, T.L., Guo, Y.S. (2010): Overwintering habitat selection of Asiatic toad, Bufo gargarizans in southwestern China. Biharean Biol. 4: 15-18.