Biodiversity directly influences the delivery of multiple ecosystem services, most notably within agriculture. Projected future global demands for food, fiber and bioenergy will require enhancement of agricultural productivity, but favoring biodiversity-based ecosystem services generally remains underutilized in agricultural practice. In addition, agricultural intensification is a key driver of biodiversity loss. A significant obstacle preventing the adoption of ecologically sensitive practices is a lack of knowledge of the species delivering the services. Insectivorous bats have long been suggested to regulate insect pest populations and may be a critical component of biodiversity-based ecosystem services. Bats may also serve as agents of insect pest surveillance through environmental DNA (eDNA) monitoring approaches. However, the biological and economic importance of bats to agriculture remains under-quantified. Here we catalogued the dietary niche of two North American bats, little brown bat (Myotis lucifugus) and big brown bat (Eptesicus fuscus), through DNA metabarcoding of guano collected from seven roosting sites over a 26-week period. We measured the frequency of occurrence of known pest species in guano samples, compared interspecific differences in diet, and examined seasonal patterns in prey selection. Overall, we detected 653 unique prey species, 160 of which were known agricultural pests or disease vectors. Species diversity of prey species consumed varied by bat species and across the season, with big brown bats accounting for the majority of arthropod diversity detected. However, little brown bats consumed relatively more aquatic insects than big brown bats, suggesting that increased bat species richness in a landscape can amplify their net pest regulation service. Further, we hypothesized that detection probabilities of target insect pests would be higher in guano samples than in conventional survey methods. Multi-survey occupancy modeling revealed significantly lower detectability in bat guano than in conventional monitoring traps, however, highlighting important tradeoffs in selection of survey methods. Overall, the results presented here contribute to a growing evidence base supporting the role bats play in the provisioning of biodiversity-based ecosystem services.

生物多样性直接影响多种生态系统服务的提供，尤其是在农业领域。预计未来全球对粮食、纤维和生物能源的需求将需要提高农业生产力，但在农业实践中，支持基于生物多样性的生态系统服务通常仍未得到充分利用。此外，农业集约化是生物多样性丧失的关键驱动因素。阻碍采用生态敏感做法的一个重要障碍是缺乏对提供服务的物种的了解。长期以来，食虫蝙蝠一直被认为可以调节害虫种群，并且可能是基于生物多样性的生态系统服务的重要组成部分。蝙蝠还可以通过环境 DNA (eDNA) 监测方法充当害虫监测的代理。然而，蝙蝠对农业的生物学和经济重要性仍未得到充分量化。在这里，我们对两种北美蝙蝠的饮食生态位进行了编目，小棕蝙蝠（Myotis lucifugus ) 和大棕色蝙蝠 ( Eptesicus fuscus ))，通过对 26 周内从七个栖息地收集的鸟粪进行 DNA 元条形码编码。我们测量了鸟粪样本中已知害虫物种的出现频率，比较了饮食的种间差异，并检查了猎物选择的季节性模式。总体而言，我们检测到 653 种独特的猎物，其中 160 种是已知的农业害虫或疾病媒介。蝙蝠种类和整个季节消耗的猎物物种多样性不同，大棕蝙蝠占检测到的节肢动物多样性的大部分。然而，小棕蝠比大棕蝠消耗的水生昆虫相对更多，这表明景观中蝙蝠物种丰富度的增加可以扩大其净害虫调节服务。更远，我们假设鸟粪样本中目标害虫的检测概率高于常规调查方法。多调查占用模型显示蝙蝠粪便中的可检测性显着低于传统监测陷阱，然而，突出了调查方法选择的重要权衡。总体而言，此处提供的结果有助于支持蝙蝠在提供基于生物多样性的生态系统服务中所发挥作用的证据基础不断增加。