Fig.1. Honey bee (Apis mellifera) collecting pollen (Credit: Jon Sullivan)
Last summer, all 45,000 bumblebees from the National Museum of Natural History’s entomology collections were digitized. This enormous project involved taking pictures of each specimen with their accompanying data and uploading this information into an online database. Collection digitization has become an increasingly popular method for both preserving sample information and offering greater accessibility - in this case, to one of the world’s largest bumblebee collections. With the unfortunate declines in bumblebee and honey bee populations, physical and digital collections offer an opportunity for conservation and research that might otherwise be impossible.
Over the past 60 years, European honey bee (Apis mellifera) colonies in the United States have dropped from six million to two million beehives. The past nine years have seen the largest decline, with an average of 30 percent or more colony loss each winter across the US. The cause of this loss, known as the Colony Collapse Disorder (CCD), has baffled both beekeepers and scientists. In addition to declines of the European honey bee, which is used in agriculture, wild bee populations are also losing members. This drop caught the attention of one Dutch research team that decided to go back in time in order to understand the problem.
Thousands of bees, similar storyJeroen Scheper, a graduate student at Wageningen University in the Netherlands, combed through 140 years worth of bee specimens with the help of his colleagues.They studied wild bee specimens from seven different natural history museums in the Netherlands and Belgium, as well as distribution reports from the European Invertebrate Survey. Scheper and his fellow scientists found that food limitation was key in driving population loss. As humans spread and increased intensive agricultural practices, native plants disappeared. Bees that depend upon specific pollen lost their food supply and certain species dropped significantly in number.
Scheper was not alone in looking toward collections. Another study led by Ignasi Bartomeus at Rutgers University documented a 30-percent loss in bumblebee populations after surveying more than 30,000 specimens and 438 species of wild bees from collections at the American Museum of Natural History, the New York State Museum, and several university museums. Yet another study of pollinator records at the University of Northampton discovered that some bee and wasp species had been dying out in Britain for more than a century. These regional and national collections tell a similar tale: too many bees are dying.
Fig.2. This bumblebee species, Bombus occidentalis, has nearly been wiped out in some areas of North America, however there is hope for some recovery (Credit: USGS Bee Inventory and Monitoring Lab, Beltsville, MD, 2014)
Bees, disease, and our food supplyWhy look toward collections for a current problem? Some researchers, like Scheper, believe the answer to missing bees is in our past. A lack of habitat and shortage of flowers certainly harm wild bee populations, as Scheper et al. found. Honey bees, however, are susceptible to diseases, such as the Varroa mite and the fungus Nosema ceranae, which have the ability to cross over to their wild bumblebee cousins. To complicate the matter, researchers have found links between pesticide use and bee loss and are still learning about the effect of climate change on pollinators.
The tale these collections tell have dangerous implications. First, the majority of food crops are dependent upon animal pollinators, and honey bees alone contribute $15 billion to the U.S. economy. A loss of bee populations means less food security for people who depend upon these crops and a large blow to the economy. Additionally, a recent study suggests that pollinator decline could put several developing countries at an increased risk for malnutrition and diseases like malaria. Our food crops, economies, and public health are harmed if bee populations continue to lose members.
Collecting for conservationLuckily, all hope is not lost. In addition to increased public awareness and scientific focus, governments are taking steps towards protecting our pollinators. The White House released a memo last June calling for the creation of a federal strategy to promote the health of honey bees and other pollinators. Internationally, groups like the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) are working to assess the role of pollinators in ecosystems in order to advise on policy responses. More money is being funneled towards research, land management, and education.
Additionally, digitization projects and efforts by scientists to document loss contribute to pollinator conservation. Collections maintain vital records of history that aid in our understanding of ecosystem health, agricultural efforts, and public health. They are the basis for research that informs policymakers on how to mitigate this loss and, hopefully, preserve bee populations for years to come.
Bartomeus, I., Ascher, J.S., Gibbs, J., Danforth, B.N., Wagner, D.L., Hedtke, S.M., & Winfree, R. Historical changes in northeastern US bee pollinators related to shared ecological traits. PNAS, 110(12): 4656-4660. doi: 10.1073/pnas.1218503110.
Brown, J.E. & University of Vermont. (2015, Jan 26). Got Bees? God Vitamin A? Got Malaria? [Press release]. Retrieved from http://www.uvm.edu/~uvmpr/?Page=news&storyID=20032&category=ucommfeaturea.
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