Sagehen Creek Field Station

30 May, 02 AM - 30 Jun, 10 AM

What determines bee population sizes in the wild? Answering this question is important for understanding how different types of environmental change will affect bees and the plants they pollinate. Populations of solitary bees may sometimes be regulated by top-down forces such as predators or parasites, but they are more often thought to be limited from the bottom up, by resource availability?either food or nesting substrates. However, there have been few direct tests of factors limiting bee populations, in part simply because obtaining unbiased estimates of population size is difficult. For this study, we will focus on a set of cavity-nesting Osmia species that are specialist visitors of early-flowering Asteraceae. We will add artificial nesting habitat (trap-nests) to sites with the host plants (mainly Balsamorhiza and Wyethia spp.) and monitor bee abundances on flowers at manipulated and control sites. The specialist habit of the bees allows us to target their specific host plants for observations. Bee abundance, the primary response variable, will be estimated at each site using mark-recapture techniques. Floral resources and natural nesting resources will also be quantified. These data will allow us to evaluate if, and under what conditions, cavity-nesting bee species are likely to be limited by nest site availability.

Visit #24468 @Sagehen Creek Field Station

Approved

Under Project # 23323 | Research

Cavity-nest supplementation to test nest-site limitation in mason bees (Osmia spp., Megachilidae)

research_scientist - University of California, Davis

Reservation Members(s)

Jessica Forrest May 30 - Jun 30, 2011 (32 days)
Jessica Forrest May 30 - Jun 30, 2011 (32 days)

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Day Use 2 May 30 - Jun 30, 2011