Recent research

In the article Detecting insect pollinator declines on regional and global scales Gretchen LeBuhn and co-authors outline a simple method for a global network of people monitoring bee populations to form an early warning system alerting scientists to dangers threatening the world’s food system and economies. The study found that counting and identifying bees, using seven different methods of sampling, regularly for five years in 200 locations, would produce data accurate enough to detect a 2-5% annual decline in bee populations. The monitoring programme would cost an estimated US$2 (€1.5) million and includes international sampling sites, although it could be scaled to fit different regional monitoring needs. The cost is a relatively small investment compared to the potential economic cost of severe pollinator losses: 35% of the global food supply depends on bees and other pollinators, including crops worth US$200 (€150) billion each year.

The study explains that a monitoring programme must be simple, repeatable, inexpensive, and, most importantly, have the ability to quickly detect declines if they are occurring. The proposed system relies on paid workers around the globe to count and identify bees using simple pan traps, in which bees are attracted to a brightlycoloured pan filled with liquid. To determine scalable sampling techniques, costs and time scales for completing the work, the researchers designed simulations using data from 11 previously published multi-year studies. The research was funded by the UN Food and Agriculture Organization (FAO). The programme has already been used in Brazil, Ghana, India, Kenya, Nepal, Pakistan and South Africa, with support from the Global Environment Facility and UN Environment Programme. LeBuhn said the long-term goal of the project is to establish a network of monitoring stations to provide data for global analysis and to centralise data collection so that people who are counting bees regionally can contribute to a larger data set.

LeBuhn is known also for organising the annual Great Sunflower Project when 100,000 citizen-scientists volunteers across North America count bee populations in their own backyards. The project, now in its fifth year, found low numbers of bees in urban areas across the USA adding weight to the theory that habitat loss is one of the primary reasons for sharp population declines.

Philip Riley, San Francisco State University Communications

Citation: Lebuhn, G., Droege, S., Connor, E. F., Gemmill-Herren, B., Potts, S. G., Minckley, R. L., Griswold, T., Jean, R., Kula, E., Roubik, D. W., Cane, J., Wright, K. W., Frankie, G. and Parker, F. (2012), Detecting Insect Pollinator Declines on Regional and Global Scales. Conservation Biology. doi: 10.1111/j.1523-1739.2012.01962.