Location: Invasive Species and Pollinator Health
2020 Annual Report
Objectives
Pollinators, such as honey bees and other insects, are critical components of both natural ecosystems and agroecosystems, ensuring the production of many agronomic crops.
Objective 1: Employing long-term, longitudinal studies of honey bee survivorship under current management conditions for honey bees used as pollinators and honey producers, elucidate honey bee forage needs and causes of mortality to serve as the basis for best management practices for pollination of specialty crops such as almond. [NP305, Component 2, Problem Statements 2A, 2B, 2C]
Approach
Honey bees are the main pollinators of crops in the United States and worldwide. Losses of honey bees due to a variety of factors are unsustainable at the current levels of over 30 percent. To mitigate these losses, it is necessary to determine their causal factors; however, long-term baseline data for colony survivorship is not available that can be used to parse the relative importance of suspected factors. It is therefore crucial to develop such a methodology, particularly as part of long-term longitudinal studies of spatial and temporal changes in bee populations exposed to a number of abiotic and biotic stresses and management practices. These longitudinal studies may incorporate research on pesticide, pathogen/pest, and nutrition/forage or other bee health effects, using hives that are stationary as well as those that follow pollination service migratory routes. The proposed longitudinal studies support ARS National Program on Production (NP305) Action Plan research objectives; Component 2: Bee Health; Problem Statements 2A: Bee Management—Improving Bee Nutrition and Performance, 2B: Bee Health—Mitigating the Impacts of Pathogens, Pests, and Pesticides, and 2C: Maximizing Bee Pollination and Quantifying Bee Forage Requirements of the Action Plan.
Progress Report
This is the final report for project 2030-21000-001-00D, “Longitudinal Studies to Determine the Causes of Honey Bee Loss studies,” which has been replaced by bridging project 2030-21000-053-00D. The project focuses on establishing a new honey bee research program in Davis, California, and initiating long-term monitoring of honey bee health in the state.
Efforts in 2015 included initiating a land lease process with the University of California (UC) Davis to secure space for a USDA facility adjacent to the existing Laidlaw Honey Bee Research Facility. Two offices for the new scientists were identified within the University of California at Davis Entomology and Nematology Department building in Briggs Hall. An agreement was also developed through the department to position mobile office and laboratory facilities adjacent on the land leased from the University. Purchase of these new facilities was completed during 2015 but delivery occurred in 2016 to the USDA’s facility in Albany, California, for temporary storage until the site land lease was secured. A stakeholder workshop was organized in 2016 as part of the development of a long-term action plan for longitudinal research activities. Efforts in 2016 also focused on recruiting the new scientists to work on the project, as well as working with the university on the land lease agreement and local site improvements. Interviews of scientific staff occurred during 2017 and selections were made, but the federal hiring freeze halted progress on filling the scientific positions. The land lease agreement was approved in 2017 and site infrastructure (parking lot, utilities, sewer, etc.) was completed in early 2018. Mobile laboratory and office facilities were moved to their permanent location in Davis during 2018. During the same year, reprioritization resulted in the re-advertisement of the two scientist positions. Interviews were conducted in 2019 and selections were made. One scientist joined the program in June 2019 and the second in September. The facilities were considered fully functional and suitable for occupation in 2019, after which equipment was installed. In 2019, an additional mobile facility was purchased to add additional office and research space for the growing program. A formal opening and dedication ceremony was held in Jan. 2020, involving stakeholder collaborators, national and regional directors.
A collaborative project on assessing risk of honey bees to pesticides was also initiated with scientists at UC Davis. Honey bees are the most effective pollinators of fruit and nut crops, such as cherries, apples and almonds; row crops, such as cucurbits and melons; and oilseed crops (sunflowers and canola), contributing over $200 billion to the country’s economy. Despite this, bees continue to face debilitating challenges relating to a number of interactive factors including poor quality and insufficient nutrition, indiscriminate use of agrochemicals, and improper hive management. These factors have systematically led to colony susceptibility to a range of pests and pathogens. The risk of these pesticides to bees is still largely unknown, particularly beyond field scale trials and single exposure events. To better understand large-scale patterns of pesticide risk, ARS scientists are collaborating with UC Davis scientists to develop predictive maps and validate these predictions with empirical pesticide loads sampled from sentinel hives. University collaborators have unified the 2017 California Pesticide Use Report and state-wide parcel data for Yolo, Sutter, and Colusa counties. For 37 pesticides, the amount, timing, and parcel- specific application location have been quantified. Scientists have collated separate data on decay rate and toxicity to bees of these chemicals. This fine-scale spatiotemporal data has been combined with an existing predictive bee foraging model available from the scientific literature. Next steps include testing sensitivity of predictions to specific foraging model settings and identifying specific pesticide concerns. In the coming season, scientists will begin evaluation of the preliminary model and testing correspondence of predicted pesticide risk with field measured pesticide loads observed in sentinel hives. This effort will generate, for the first time, landscape-scale risk maps for an important and pollinator-dependent agricultural region. In addition to this landscape level pesticide analyses, the scientists will begin nutritional content of pollen from honey bee hives beginning from almond flowering in February through the end of the season in September.
Accomplishments
