Collaborative Research: Effects of pulsed floral resources on pollinator population dynamics

这项研究将探讨景观变化的一个结果，鲜花的时间和可用性，如何影响大黄蜂的种群，大黄蜂是一组突出的本土蜜蜂，在北美为许多作物和野花授粉。 大黄蜂很重要，因为我们吃的食物中有三分之一以上来自农作物，而农作物在某种程度上取决于它们提供的授粉类型。 虽然非本土蜜蜂仍然是农业授粉的基石，但鉴于蜜蜂面临的持续挑战，本土蜜蜂越来越成为农业关注的焦点。健康的本土蜜蜂群体依赖于花粉和花蜜的持续供应。 然而，这些花卉资源的可用性已被与气候变化相关的不可预测的天气以及人类活动（包括集约化农业）所极大地改变。 研究人员将研究鲜花的时间和可用性的变化如何影响熊蜂的数量。 这项研究是过去研究的一个重大进步，过去的研究使用蜜蜂访问花朵的模式来对蜜蜂种群和社区的整体健康做出广泛的结论。 相比之下，目前的研究将集中在蜂箱的繁殖成功。研究结果将是制定战略的关键，以促进强大的蜜蜂种群，确保粮食安全，以及保护生物多样性。 具体而言，该项目结合了人工现场实验和原始人口模型，以评估年内资源变化（资源脉冲）对熊蜂种群动态的影响。 实验将用沃斯内森斯基熊蜂进行，这是北方加州的一种主要熊蜂物种。 研究人员将进行实验，其中花的可用性和时间被系统地改变。然后，他们将测量单个菌落的生命率（例如，工蜂产量、工蜂存活率和蜂王产量）取决于在殖民地生命周期中不同时期花资源的可用性。 为了确保蜂箱质量的一致基线，所有测量都将在从野生收集的蜂王开始的实验室饲养的菌落上进行。 实验结果将结合人口统计模型来预测蜜蜂在不同景观条件下的长期种群生存能力。 这项研究将回答有关持续的景观变化将如何影响熊蜂和其他蜜蜂物种的问题。它还将为蜜蜂和其他社会昆虫的种群生存能力分析提供一个以前缺少的框架。

This research will explore how one result of landscape change, the timing and availability of flowers, affects populations of bumble bees, a prominent group of native bees that pollinate many crops and wildflowers in North America. Bumble bees are important because more than one-third of the food we eat comes from crops that depend to some degree on the type of pollination they provide. Although non-native honey bees remain a cornerstone of agricultural pollination, native bees are increasingly the focus of agricultural attention in light of ongoing challenges facing honey bees. Healthy populations of native bees rely on continuous supplies of pollen and nectar. However, the availability of these floral resources has been dramatically altered by unpredictable weather associated with changing climate, and by human activities, including intensive agriculture. The investigators will study how changes in the timing and availability of flowers affect the number of bumble bees. This research is a significant advance over past studies, which used patterns of bee visits to flowers to make broad conclusions about the overall health of bee populations and communities. In contrast, the current study will focus on reproductive success of bee hives. The results will be key to developing strategies to promote robust populations of bees and ensure food security, as well as to conserve biological diversity. Specifically, the project combines manipulative field experiments and original demographic population models to assess effects of within-year resource variation (resource pulses) on population dynamics of bumble bees. The experiments will be conducted with Bombus vosnesenskii, a dominant bumble bee species in Northern California. Investigators will conduct experiments in which flower availability and timing are systematically altered. They will then measure how vital rates of individual colonies (e.g., worker production, worker survival, and queen production) depend on the availability of floral resources at different times in the colony life cycle. To ensure a consistent baseline of hive quality, all measurements will be made on lab-reared colonies started from wild-collected queens. Experimental results will be combined with demographic models to predict long-term population viability of bees under different landscape conditions. This research will answer questions about how ongoing landscape change will affect Bombus vosnesenskii and other bee species. It also will provide a previously-missing framework for population viability analysis of bees and other social insects.