School of Natural Science, Hampshire College, Amherst, MA, United States of America.
Department of Mathematics & Statistics, Amherst College, Amherst, MA, United States of America.
PLoS One. 2021 Jan 6;16(1):e0244458. doi: 10.1371/journal.pone.0244458. eCollection 2021.
Behavioral thermoregulation is an important defense against the negative impacts of climate change for ectotherms. In this study we examined the use of burrows by a common intertidal crab, Minuca pugnax, to control body temperature. To understand how body temperatures respond to changes in the surface temperature and explore how efficiently crabs exploit the cooling potential of burrows to thermoregulate, we measured body, surface, and burrow temperatures during low tide on Sapelo Island, GA in March, May, August, and September of 2019. We found that an increase in 1°C in the surface temperature led to a 0.70-0.71°C increase in body temperature for females and an increase in 0.75-0.77°C in body temperature for males. Body temperatures of small females were 0.3°C warmer than large females for the same surface temperature. Female crabs used burrows more efficiently for thermoregulation compared to the males. Specifically, an increase of 1°C in the cooling capacity (the difference between the burrow temperature and the surface temperature) led to an increase of 0.42-0.50°C for females and 0.34-0.35°C for males in the thermoregulation capacity (the difference between body temperature and surface temperature). The body temperature that crabs began to use burrows to thermoregulate was estimated to be around 24°C, which is far below the critical body temperatures that could lead to death. Many crabs experience body temperatures of 24°C early in the reproductive season, several months before the hottest days of the year. Because the use of burrows involves fitness trade-offs, these results suggest that warming temperatures could begin to impact crabs far earlier in the year than expected.
行为体温调节是变温动物应对气候变化负面影响的重要防御机制。在这项研究中，我们研究了一种常见的潮间带螃蟹 Minuca pugnax 利用洞穴来控制体温的情况。为了了解体温如何响应表面温度的变化，并探索螃蟹如何有效地利用洞穴的冷却潜力进行体温调节，我们在 2019 年 3 月、5 月、8 月和 9 月在佐治亚州萨佩洛岛的低潮期间测量了螃蟹的身体、表面和洞穴温度。我们发现，表面温度升高 1°C，雌性螃蟹的体温升高 0.70-0.71°C，雄性螃蟹的体温升高 0.75-0.77°C。对于相同的表面温度，小雌蟹的体温比大雌蟹高 0.3°C。与雄性螃蟹相比，雌性螃蟹更有效地利用洞穴进行体温调节。具体来说，冷却能力（洞穴温度与表面温度之差）增加 1°C，雌性螃蟹的体温调节能力（体温与表面温度之差）增加 0.42-0.50°C，雄性螃蟹的体温调节能力增加 0.34-0.35°C。螃蟹开始利用洞穴进行体温调节的体温估计在 24°C 左右，远低于可能导致死亡的临界体温。许多螃蟹在繁殖季节早期，也就是一年中最热的日子前几个月，就会经历 24°C 的体温。由于利用洞穴涉及到适应度的权衡，这些结果表明，气温升高可能会比预期更早地开始影响螃蟹。
