Data to accompany manuscript "Sub-zero temperatures during early spring migration in Blue-spotted Salamanders"

Abstract from the paper for which the data apply provided: Amphibians that reproduce in early spring at northern latitudes may encounter environmental ice while migrating to their breeding sites. Due to the nucleation properties of ice, contact with environmental ice may induce rapid freezing of body tissues, which can cause irreversible damage to cells and lead to death. Although some species of salamanders are known to move over ice during early spring migration, freeze-intolerant species are expected to avoid physical contact with ice crystals to minimise the risk of freezing. Here, we documented the thermal biology of the freeze-intolerant Blue-spotted Salamander (Ambystoma laterale) migrating at sub-zero temperatures in Algonquin Provincial Park, Ontario, Canada. During our surveys, we found sheltered, inactive, and migrating individuals; some in direct contact with ice. Our field measurements of skin temperature using high resolution thermal imaging suggest that the Blue-spotted Salamander can sustain activity in a supercooled state (i.e., chilled below the freezing point of body fluids but not frozen). By migrating in a supercooled state, these salamanders may overcome the risk of freezing while simultaneously prolonging their breeding season and potentially avoiding predators.

本数据集所依托的论文摘要如下：在高纬度地区早春繁殖的两栖动物，在前往繁殖地的迁徙过程中可能接触到环境冰体。由于冰的成核特性，接触环境冰体可能引发机体组织快速冻结，进而对细胞造成不可逆损伤并导致个体死亡。尽管已有研究证实部分蝾螈物种会在早春迁徙期间于冰面活动，但不耐冻物种理应避免与冰晶直接接触，以最大限度降低结冰风险。本研究针对加拿大安大略省阿尔贡金省立公园内，于零下温度环境下迁徙的不耐冻物种蓝点钝口螈（Ambystoma laterale）的热生物学特性进行了记录。调查期间，我们发现了隐匿休憩、静止不动以及正在迁徙的个体，其中部分个体直接与冰体接触。我们采用高分辨率热成像技术开展的皮肤温度野外测量结果显示，蓝点钝口螈能够在过冷状态（supercooled state）下维持活动，即机体体温降至体液冰点以下但并未发生冻结。这类蝾螈通过以过冷状态进行迁徙，既能够规避结冰风险，同时还可延长繁殖季，并潜在地躲避天敌。