Mychajliw Alexis M, Almonte Juan N, Martinez Pedro A, Hadly Elizabeth A
Departments of Biology and Environmental Studies Middlebury College Middlebury Vermont USA.
Department of Biology Stanford University Stanford California USA.
Ecol Evol. 2022 Mar 24;12(3):e8761. doi: 10.1002/ece3.8761. eCollection 2022 Mar.
While trends in tropical deforestation are alarming, conservation biologists are increasingly recognizing the potential for species survival in human-modified landscapes. Identifying the factors underlying such persistence, however, requires basic ecological knowledge of a species' resource use. Here, we generate such data to guide conservation of an understudied venomous mammal, the Hispaniolan solenodon (), that occupies a mosaic landscape of agriculture and forest fragments in the western Dominican Republic. Using feces collected in both wet and dry seasons, we found significant differences in the stable isotope values of carbon (δC) between pasture (-24.63 ± 2.31‰, Las Mercedes) and agroforestry (-28.07 ± 2.10‰, Mencia). Solenodon populations in agricultural areas occupied wider isotopic niche spaces, which may be explained by more diverse resource within these patches or individuals combining resources across habitats. We detected elevated δN values in the dry season of pasture areas (8.22 ± 2.30‰) as compared to the wet season (5.26 ± 2.44‰) and overall narrower isotopic niche widths in the dry season, suggestive of the impacts of aridity on foraging behavior. Our work highlights the importance of considering a more nuanced view of variations in 'modified' or "agricultural" landscapes as compared with strictly protected national parks. We suggest that seasonal differences in foraging should be considered as they intersect with landscape modification by landowners for maintaining resources for focal consumers. This work adds to a growing body of literature highlighting that fecal stable isotopes are a non-invasive and cost-effective monitoring tool that is particularly well-suited for cryptic small mammal species, ensuring actionable and evidenced-based conservation practices in the tropic's rapidly changing landscapes.
尽管热带森林砍伐的趋势令人担忧,但保护生物学家越来越认识到人类改造后的景观中物种生存的潜力。然而,要确定这种持久性背后的因素,需要了解物种资源利用的基本生态知识。在这里,我们生成这些数据以指导对一种研究较少的有毒哺乳动物——伊斯帕尼奥拉岛沟齿鼩(Solenodon paradoxus)的保护,该物种栖息在多米尼加共和国西部由农业和森林碎片组成的镶嵌景观中。通过收集湿季和干季的粪便,我们发现牧场(-24.63 ± 2.31‰,拉斯梅塞德斯)和农林复合系统(-28.07 ± 2.10‰,门西亚)之间碳的稳定同位素值(δC)存在显著差异。农业区域的沟齿鼩种群占据了更宽的同位素生态位空间,这可能是由于这些斑块内资源更多样化,或者个体在不同栖息地之间组合资源。我们检测到,与湿季(5.26 ± 2.44‰)相比,牧场区域干季的δN值升高(8.22 ± 2.30‰),且干季的同位素生态位宽度总体更窄,这表明干旱对觅食行为有影响。我们的研究强调了与严格保护的国家公园相比,对“改造”或“农业”景观变化采取更细致入微观点的重要性。我们建议,在考虑土地所有者为重点消费者维持资源而对景观进行改造时,应考虑觅食的季节性差异。这项工作为越来越多的文献增添了内容,这些文献强调粪便稳定同位素是一种非侵入性且具有成本效益的监测工具,特别适合隐秘的小型哺乳动物物种,可确保在热带地区迅速变化的景观中采取切实可行且有证据支持的保护措施。