Wetlands are essential habitats for amphibians, but for many species, no information is available regarding how and when they make use of the different environments within the upland-wetland ecotone, nor which variables affect spatial and temporal distribution. We sought to determine the habitat preferences of two tree frog species using a capture-recapture approach in a wetland located in the Paraguayan Humid Chaco. We also evaluated the water quality and its influence on the abundance of these tree frog species. We measured 12 water quality parameters and sampled tree frogs using 168 PVC pipes in the wetland and adjacent riparian forest. Four sampling campaigns were carried out during the wet season in November 2017, January, and March 2018, and the dry season in May 2018. We captured 1578 individuals of Scinax nasicus and 156 individuals of Dendropsophus nanus. We found that terrestrial habitats adjacent to wetlands play an important role in the biology of tree frog species, especially for S. nasicus. This species seeks permanents shelters away from the high-water line in the floodable forest during the dry season. D. nanus also showed a marked seasonal pattern, using the PVC pipes mainly in the dry season, but a pattern in habitat preference could not be determined. The water quality parameters indicated a certain degree of eutrophication in the wetland and we also found high average concentrations of fecal coliforms. We found a negative correlation between the abundance of frogs and the presence of fecal coliforms during the dry season.

湿地是两栖动物必不可少的栖息地，但对于许多物种，没有关于它们如何以及何时利用高地 - 湿地交错带内的不同环境的信息，也没有哪些变量会影响空间和时间分布。我们试图在位于巴拉圭潮湿查科的湿地中使用捕获-重新捕获方法确定两种树蛙物种的栖息地偏好。我们还评估了水质及其对这些树蛙物种数量的影响。我们在湿地和邻近的河岸森林中使用 168 根 PVC 管测量了 12 个水质参数并采样了树蛙。在 2017 年 11 月、2018 年 1 月和 3 月的雨季和 2018 年 5 月的旱季期间进行了四次采样活动。 我们捕获了 1578 只Scinax nasicusDendropsophus nanus 156 只。我们发现湿地附近的陆地栖息地在树蛙物种的生物学中发挥着重要作用，尤其是对于S. nasicus。在旱季，这个物种在可浸水的森林中寻找远离高水位线的永久避难所。D. nanus也表现出明显的季节性模式，主要在旱季使用 PVC 管，但无法确定栖息地偏好的模式。水质参数表明湿地存在一定程度的富营养化，我们还发现粪便大肠菌群的平均浓度很高。我们发现旱季青蛙的数量与粪便大肠菌群的存在呈负相关。