DataSheet_1_Potential fitness consequences of roosting spatiotemporal selection in an endangered endemic damselfly: conservation implications.pdf

Understanding habitat requirements of species of conservation concern is central for their conservation and management. Although much of the research attention has been focused on reproductive sites, the understanding of roosting behavior and microhabitat selection, and their potential fitness consequences is also crucial. Here, we assess the roosting behavior of an endangered endemic damselfly Calopteryx exul Selys in a lotic habitat of Northeast Algeria. Based on marked individuals, we specifically investigated their vertical and horizontal distribution at roosting sites, as well as the timing of roosting and its correlation with lifespan (as a measure of fitness). We found that individuals were philopatric to roosting sites and less so to vertical stratification. Roosting sites were used for both foraging and roosting. Individuals that occupied lower strata in roosting sites had longer lifespans and ceased roosting earlier. Average temperature of the day affected the timing of roosting such that on warm days roosting started later and ended earlier. Individuals with longer lifespans roosted earlier, suggesting potential scramble competition for roosting sites. Our results suggest that C. exul individuals show variability in the vertical and horizontal location as well as the timing of roosting, and these choices potentially have fitness consequences. This study highlights the importance of bank vegetation as roosting sites for lotic insects, and emphasizes the benefits of protecting these sites and including them as integral parts of the conservation plans of species.

厘清受保护关注物种的栖息地需求，是其保护与管理工作的核心要义。尽管过往多数研究多聚焦于繁殖栖息地，但对栖宿行为(roosting behavior)、微生境选择(microhabitat selection)及其潜在适合度(fitness)影响的认知同样不可或缺。
本研究于阿尔及利亚东北部的流水生境(lotic habitat)中，针对濒危特有豆娘*Calopteryx exul Selys*的栖宿行为开展了系统评估。基于标记个体，本研究重点探究了该豆娘在栖宿地的垂直与水平分布格局，同时考察了其栖宿时段及其与作为适合度衡量指标的寿命之间的关联。
研究结果显示，该豆娘个体对栖宿地具有恋地性，但对垂直分层的依恋程度相对较弱。栖宿地同时被用于觅食与栖宿活动。占据栖宿地下层生境的个体寿命更长，且更早结束栖宿时段。当日平均气温会影响栖宿时段：气温偏高的日间，个体的栖宿开始时间更晚、结束时间更早。寿命更长的个体栖宿开始时间更早，这暗示栖宿地可能存在潜在的争夺型竞争。
本研究结果表明，*C. exul*个体在栖宿的垂直与水平位置以及栖宿时段上均存在变异，而这些栖宿选择可能会对其适合度产生影响。本研究凸显了岸带植被作为流水昆虫栖宿地的重要价值，并强调了保护这类栖宿地、将其纳入物种保护规划核心组成部分的必要性。