Gould John, Larkin Claire, McHenry Colin
School of Environmental and Life Sciences University of Newcastle Callaghan New South Wales Australia.
Ecol Evol. 2025 Mar 30;15(4):e71057. doi: 10.1002/ece3.71057. eCollection 2025 Apr.
Amphibian tadpoles are typically aquatic and constrained to freshwater throughout development. These circumstances change at metamorphosis, whereupon individuals may complete a partial or full habitat shift towards terrestriality and gain the capacity to transition between habitat types. In this study, we present evidence of striped marsh frog tadpoles, , resting out of the water on floating vegetation mats in freshwater ponds, despite being fully aquatic and at a developmental stage far proceeding metamorphosis. We propose that this behaviour may represent a form of adaptive beaching to obtain survival benefits that are derived from being out of the water column. In particular, this may be a behavioural tactic of habitat switching to avoid aquatic predators, such as the introduced mosquitofish, , or to access oxygen from the air when the water becomes hypoxic. The capacity for aquatic tadpoles to exploit temporary refuges outside the water challenges traditional assumptions about their strict dependence on being continuously submerged below the surface for survival. While our findings are preliminary and based on a small sample size, they suggest the aquatic tadpoles of our focal species and perhaps others are not as restricted to their natal waterbodies as previously thought and that they have the capacity to move into habitats above the water's surface for resource gain.
两栖类蝌蚪通常生活在水中，在整个发育过程中都局限于淡水环境。这些情况在变态时会发生变化，此时个体可能会部分或完全向陆地栖息地转变，并获得在不同栖息地类型之间转换的能力。在本研究中，我们提供了条纹沼蛙蝌蚪的证据，尽管它们完全水生且处于远未变态的发育阶段，但却在淡水池塘中漂浮的植被垫上露出水面休息。我们认为这种行为可能代表了一种适应性搁浅形式，以获得来自离开水柱的生存益处。特别是，这可能是一种栖息地转换的行为策略，以避免水生捕食者，如引入的食蚊鱼，或者在水体缺氧时从空气中获取氧气。水生蝌蚪利用水体之外临时避难所的能力挑战了关于它们严格依赖持续淹没在水面以下以生存的传统假设。虽然我们的发现是初步的且基于小样本量，但它们表明我们所关注物种以及可能其他物种的水生蝌蚪并不像之前认为的那样局限于其出生的水体，并且它们有能力进入水面以上的栖息地以获取资源。
