CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos Laboratório Associado, Universidade do Porto, Campus Agrário de Vairão, 4485-661, Vairão, Portugal.
CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos Laboratório Associado Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017, Lisboa, Portugal.
Sci Rep. 2023 Mar 23;13(1):4726. doi: 10.1038/s41598-023-31746-x.
Elevated temperatures can have a range of fitness impacts, including high metabolic cost of thermoregulation, hence access to microclimate refugia may buffer individuals against exposure to high temperatures. However, studies examining the use of microclimate refugia, remain scarce. We combined high resolution microclimate modelling with GPS tracking data as a novel approach to identify the use and availability of cooler microclimate refugia (sites > 0.5 °C cooler than the surrounding landscape) at the scales experienced by individual animals. 77 little bustards (Tetrax tetrax) were tracked between 2009 and 2019. The 92,685 GPS locations obtained and their surrounding 500 m areas were characterised with hourly temperature and habitat information at 30 m × 30 m and used to determine microclimate refugia availability and use. We found that the semi-natural grassland landscapes used by little bustards have limited availability of cooler microclimate areas-fewer than 30% of the locations. The use of cooler microclimate sites by little bustards increased at higher ambient temperatures, suggesting that individuals actively utilise microclimate refugia in extreme heat conditions. Microclimate refugia availability and use were greater in areas with heterogeneous vegetation cover, and in coastal areas. This study identified the landscape characteristics that provide microclimate opportunities and shelter from extreme heat conditions. Little bustards made greater use of microclimate refugia with increasing temperatures, particularly during the breeding season, when individuals are highly site faithful. This information can help identify areas where populations might be particularly exposed to climate extremes due to a lack of microclimate refugia, and which habitat management measures may buffer populations from expected increased exposure to temperature extremes.
升高的温度会对生物适应能力产生一系列影响，包括体温调节的高代谢成本，因此，个体可以利用微气候避难所来避免暴露在高温环境中。然而，关于微气候避难所利用的研究仍然很少。我们将高分辨率微气候建模与 GPS 跟踪数据相结合，作为一种新颖的方法，以确定在个体动物所经历的尺度上，更凉爽的微气候避难所（比周围景观凉爽 0.5°C 以上的地点）的利用和可用性。我们在 2009 年至 2019 年间跟踪了 77 只小鸨（Tetrax tetrax）。获得了 92685 个 GPS 位置，以及它们周围 500 m 区域的信息，这些信息以 30 m×30 m 的分辨率每小时记录温度和栖息地信息，用于确定微气候避难所的可用性和利用情况。我们发现，小鸨所使用的半自然草地景观中凉爽微气候区域的可用性有限——不到 30%的地点。小鸨在环境温度较高时更倾向于利用凉爽的微气候地点，这表明个体在极端高温条件下积极利用微气候避难所。微气候避难所的可用性和利用情况在植被覆盖不均匀的区域以及沿海地区更大。本研究确定了提供微气候机会和躲避极端高温条件的景观特征。随着温度的升高，小鸨对微气候避难所的利用程度更大，特别是在繁殖季节，此时个体对栖息地的依赖性很高。这些信息可以帮助确定由于缺乏微气候避难所而可能特别容易受到极端气候影响的区域，以及哪些生境管理措施可以使种群免受预期增加的极端温度暴露。
