Promoting Native Bee Health and Pollination Services on Diversified Organic Produce Famis

View the project final report

• 2015 annual report

Commodities

• Animal Products: honey

Practices

• Education and Training: on-farm/ranch research
• Farm Business Management: whole farm planning
• Natural Resources/Environment: biodiversity, hedgerows
• Production Systems: holistic management, organic agriculture
• Sustainable Communities: public participation, social networks, urban agriculture, urban/rural integration

Native bee communities are threatened by agricultural intensification and urbanization. The practices used by organic farming systems, and the addition of pollinator habitat, may be two means to conserve native bees and the valuable pollination services they provide. These conservation practices may be particularly important in intensive landscapes such as urban centers. Our project explored how habitat augmentation promotes native bee communities and pollination services on diversified organic produce systems across a landscape highly affected by urbanization in western WA (Seattle, Olympia, Tacoma). Our results indicate that these farming systems host at least 20 genera of bees. Urban and rural farms had similar bee diversity, but bees were significantly less abundant on urban compared to rural farms. In addition, we found that native bees visit similar plants in both urban and rural areas, indicating the conservation of pollination services across these landscapes. Habitat augmentation did not increase the abundance or diversity of bee groups, but effects of our treatments may take several years to fully manifest. The outreach component of our project consisted of six field days for growers and a citizen science initiative for bee conservation in the Puget Sound Region. Growers who attended our field days received a four hour short course on bee monitoring techniques and a packet of our extension materials and publications that are in-review. Citizen scientists have to-date contributed to over 50 records of bee biodiversity in the Puget Sound region and the nesting requirements of bees. Our work has culminated in the creation of a website, http://nwpollinators.org, which serves as a clearinghouse of information on native bee conservation as well as for our citizen science initiative.

Introduction

Diversified farming systems that produce many crops throughout a growing system are considered to be more sustainable than monocultures. Native bees are critical for the sustainability of these farming systems, and diversified farms typically achieve significantly higher yields when healthy native bee communities are present. However, we have a poor understanding of the suites of practices that promote healthy native bee communities on diversified farms. To address this knowledge gap, we established a network of 34 diversified produce farms, all of which were either certified organic or use organic practices, to evaluate factors that promote native bee community health and pollination services.

Our research objectives were to evaluate the impact of habitat augmentation on native bee community health and pollination services on diversified organic produce farms. We worked with farms located in western Washington, an area highly impacted by urbanization (i.e. Seattle, Washington). Indeed, several of our farms were surrounded almost entirely by urban development, while others were located in areas with more natural habitat (Figure 1). This is important, because urbanization has been shown to reduce available habitat for native bees. In turn, strategies that promote native bees needed to be effective in this highly-intensified and fragmented urbanized landscape.

On participating farms we established habitat in the form of flowering plant strips, nesting structures, and bare ground. These three practices were implemented to promote a diversity of nesting habitats and floral resources for many native bee species. We are evaluating how these augmentation strategies influence native bee community health and pollination services on our network of farms, and how augmentation strategies interact with the surrounding landscape to influence bee health. This research was also paired with field days and the production of a diverse set of educational materials to engage and educate growers on practices to support native bee community health and diversified farming. Moreover, through this project we initiated a citizen-science project that inspired community members to actively participate in native bee conservation. Both field days and citizen science provided a forum for farmers and community members to come together in an initiative that promoted peer-to-peer learning while also addressing native bee conservation over a broad area.

• Objective 1: Determine if habitat augmentation expedites the development of abundant, diverse, and stable native bee communities
  • Sub-objective 1a: Establish habitat augmentation treatments on farms
  • Sub-objective 1b: Sample native bee communities
  • Sub-objective 1c: Measure the effects of habitat augmentation and landscape intensity on native bee community abundance, diversity, and stability

• Objective 2: Measure the impact of habitat augmentation on pollination services
  • Sub-objective 2a: Assess pollination services on farms
  • Sub-objective 2b: Explore the effects of habitat augmentation and landscape intensity on fruit set and pollination services

• Objective 3: Educate farmers and engage community members on native bee conservation
  • Sub-objective 3a: Conduct field days to educate farmers about conserving native bees and pollination services
  • Sub-objective 3b: Establish citizen science initiative on bee conservation
    • Provide citizen scientists with native bee “mail boxes”
    • Gather data from citizen scientists to assess bee communities