School of Zoology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel.
Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China.
Integr Comp Biol. 2022 Oct 29;62(4):1031-1041. doi: 10.1093/icb/icac104.
Microhabitats provide ecological and physiological benefits to animals, sheltering them from predation and extreme temperatures and offering an additional supply of water and food. However, most studies have assumed no energetic costs of searching for microhabitats or moving between them, or considered how the availability of microhabitats may affect the energy reserves of animals and how such effects may differ between seasons. To fill these gaps, we studied how the body condition of lizards is affected by microhabitat availability in the extreme environment of the Judean Desert. In particular, we quantified how vegetation and rock cover in the vicinity of these lizards affect their body condition during summer and winter. First, we used aerial imagery to map the vegetation/rock cover at two study sites. Next, we collected 68 adult lizards and examined how their body condition varies across seasons and availability of vegetation and rock cover. In addition, we examined how vegetation and rock cover may differ in their effective distance (i.e., the distance that best explains body condition of lizards). We found that lizards body condition was better if they were collected closer to a higher availability of vegetation or rocks. However, while close proximity (within 10 m) was the best predictor for the positive effect of rocks, a greater distance (up to 90 m) was the best predictor for the effect of the vegetation cover. Moreover, the positive effect of vegetation was 12-fold higher than the effect of rocks. Interestingly, although the lizards' body condition during winter was poorer than during summer, the positive effects of rock and vegetation cover remained constant between the seasons. This similarity of benefits across seasons suggests that shaded microhabitats have important additional ecological roles regardless of climate, and that they may provide thermoregulatory benefits in winter too. We also found a synergic effect of vegetation and rock cover on the lizards' body condition, suggesting that their roles are complementary rather than overlapping. Our research has revealed the importance of shade- and shelter-providing microhabitats in both summer and winter. We suggest that proximity to microhabitat diversity may contribute to better body condition in lizards or, alternatively, facilitates competition and attracts lizards with better body condition. Comprehending the complex interactions between animals and different microhabitats is critical for developing better conservation plans, understanding the risks of climate change, and suggesting mitigation strategies.
微生境为动物提供了生态和生理上的益处，使它们免受捕食和极端温度的影响，并提供额外的水和食物供应。然而，大多数研究都假设动物在寻找微生境或在它们之间移动时不会产生能量成本，或者没有考虑微生境的可用性如何影响动物的能量储备，以及这种影响在不同季节可能会有何不同。为了填补这些空白，我们研究了在朱迪亚沙漠的极端环境中，蜥蜴的身体状况如何受到微生境可用性的影响。具体来说，我们量化了这些蜥蜴周围的植被和岩石覆盖如何影响它们在夏季和冬季的身体状况。首先，我们使用航空图像来绘制两个研究地点的植被/岩石覆盖图。接下来，我们收集了 68 只成年蜥蜴，并研究了它们的身体状况如何随季节和植被及岩石覆盖的可用性而变化。此外，我们还研究了植被和岩石覆盖在有效距离（即最能解释蜥蜴身体状况的距离）上可能有何不同。我们发现，如果蜥蜴被采集到离植被或岩石更高的可用性更近的地方，它们的身体状况就会更好。然而，虽然近距离（在 10 米内）是岩石的积极影响的最佳预测因素，但更大的距离（高达 90 米）是植被覆盖的最佳预测因素。此外，植被的积极影响是岩石的 12 倍。有趣的是，尽管蜥蜴在冬季的身体状况比夏季差，但岩石和植被覆盖的积极影响在季节之间保持不变。这种跨季节的利益相似性表明，遮荫微生境具有重要的额外生态作用，无论气候如何，它们在冬季也可能提供热调节益处。我们还发现植被和岩石覆盖对蜥蜴身体状况有协同作用，这表明它们的作用是互补的，而不是重叠的。我们的研究揭示了遮荫和遮蔽微生境在夏季和冬季的重要性。我们认为，接近微生境多样性可能有助于蜥蜴更好的身体状况，或者便于竞争，并吸引身体状况更好的蜥蜴。理解动物与不同微生境之间的复杂相互作用对于制定更好的保护计划、理解气候变化的风险以及提出缓解策略至关重要。
