A first-of-its-kind resource is helping in the fight against the dramatic decline in bee pollinator populations. Coauthors of the USDA web-based tool include Pavel Klimov, a research scientist in the University of Michigan Department of Ecology and Evolutionary Biology and the Museum of Zoology and Barry OConnor, EEB professor and curator of insects at UMMZ.

The USDA Animal and Plant Health Inspection Service’s (APHIS) Identification Technology Program has released “Bee Mite ID: Bee-associated Mite Genera of the World.” This tool allows for identification of adult and immature mite life stages found on bees and in their nests, focuses on important bee pollinators, and can help in distinguishing harmful from non-harmful mites.

This is the first comprehensive diagnostic tool for this group of wordwide, economically-important arthropods that pose a serious threat to our agriculture and natural resources. (Prior tools deal with agricultural pest “flat mites,” and other groups of insect pests.) “Bee Mite ID,” designed for use by novices to experts, features an illustrated interactive key, comprehensive fact sheets, a filterable image gallery, quick reference guides, illustrated mite and bee morphology pages, and more.

A bumblebee queen carrying phoretic stages of mites of the genus Parasitellus. Image credit: photo © Alan Smith.

Pollinating bees play an essential role in agriculture, and parasitic mites are known to be a factor in recent declines in bee pollinator populations, according to USDA. For example, Varroa destructor, an introduced mite parasite and disease vector, has decimated colonies of the European honey bee, one of the most important agricultural pollinators in the world. Global trade in alternative pollinators increases the likelihood of transporting mites, so there is a potential for more Varroa-style invasions. The tool is being  used by biosecurity specialists and beekeepers to identify the mites of greatest concern to help prevent such invasions.

A number of bee pollinators and their ecological services are facing sharp declines due to habitat destruction, pesticide use, pathogen spillover from commercial colonies, and other causes, according to Klimov. In particular, significant losses of European honey bee (Apis mellifera) populations due to diseases and attacks by parasitic mites could result in failure of crops requiring pollination – an estimated 35 percent of the human diet. Currently, the development of alternative, non-Apis pollinators is underway. Of these, mason bees (Osmia) and bumblebees (Bombus) are the most important. As the pollinator trade increases worldwide, the opportunity for introductions of new harmful mites and/or host switching also substantially increases. In addition to the direct threat posed by parasitic mites, mites colonizing new hosts may spread harmful pathogens, such as viruses, bacteria and fungi.

Only quarantine measures can prevent this situation. Prior to the release of the “Bee Mite ID,” implementing these measures was difficult because bee-associated mites are understudied, and the taxonomic information is scattered, incomplete and difficult to access by the non-specialist.

With this tool, researchers are making valuable observations and associations about bee mites, identifying potential problem mite species and introductions, which can support future risk assessments and detection and eradication efforts. This is especially important for citizen naturalists, beekeepers (managing either honeybees or replacement pollinators), sustainable crop growers, and backyard farming or bee garden enthusiasts. The tool aims to provide an understanding of the diversity and the role played by the various mite associates of native bees in their natural situations, which is necessary in order to monitor host shifts into economically important species of introduced bee pollinators from different parts of the world. As an easy-to- use, web-based resource, this tool will potentially allow for the dissemination of critical information pertaining to the classification and naming issues within the group. This will allow for ease of collaborative research efforts within the broader entomological and acarological communities.

The importance of bee pollination to the U.S. agriculture and the danger of exotic parasites of bees was recently recognized in the presidential memorandum “Pollinator Research Action Plan” which stated that it “shall be informed by research on relevant topics and include: mitigation strategies for … parasites and other pests, … and unsustainable management practices.” (Barack Obama, “Presidential Memorandum – Creating a Federal Strategy to Promote the Health of Honey Bees and Other Pollinators,” June 20, 2014). This project directly addresses the Pollinator Research Action Plan.

OConnor, the project’s co-principal investigator, is guiding and reviewing the content and project design of this identification tool. OConnor is an experienced world authority on mites, with international recognition in bee mite systematics. In 2003, he received an USDA grant to document and synthesize information on bee-associated mites in North America. OConnor serves as a primary reviewer for the content of “Bee Mite ID” and also provides resources needed to accomplish such a large scale project (for example, slide mounted mite specimens hosted at UMMZ). He has also supervised undergraduate assistants during specimen preparation.

Recent undergraduate alumni Jane Dykema, Jill Diesel and Randa Tao worked on the earlier project that produced many of the specimens of mites used in the project. More recent undergraduate students who worked preparing specimens for the Bee Mite ID project included Anna Reed, Elizabeth Pittman, Maria Wooten and Erica Marcos.

OConnor and Klimov are currently the only active systematists in North America working on mites associated with bees other than Apis. They receive many requests to identify mite species intercepted at the U.S. port of entries by the USDA.

The honey bee tracheal mite, Acarapis woodi male, dorsal view; LT-SEM (digitally colorized). Image credit: Ron Ochoa and Gary Bauchan, USDA-ARS.

Klimov previously served as a cooperator for the U.S. bee-associated mite species pages, database, and identification tools developed for USDA in collaboration with OConnor. Klimov has hands-on experience with several computer programming languages. He authored one large monograph and many research papers on bee-associated mites. He supervises undergraduate assistants, who take digital pictures of mites and their character states to be incorporated into the key and webpages and also prepare mite specimens on microscopic slides.

Klimov is a recipient of an Encyclopedia of Life (EOL) fellowship to implement data sharing between the Bee-Associated Mites website and the EOL. EOL is a large biodiversity and educational bioinformatics portal. Klimov created the script that enables nearly instantaneous data sharing between the site on bee-associated mites and the EOL. This was created in 2004, long before “Bee Mite ID," mostly to disseminate taxonomic information about bee mites.

UMMZ has the largest collection of bee-associated mites in the world with an estimated 10,000 slide-mounted specimens. This collection has been accumulated over several decades by OConnor, with a substantial portion added in 2003-2004 through the auspices of a USDA grant. Mite specimens were collected in 42 museums and research institutions in the USA and around the world by examining pinned museum bee specimens for mites, photographing mites in their original place, removing them from the bee host (with permission from curators), and mounting them on labeled microscopic slides. A total of seven families, 157 genera, 1,167 species and 4,420 individual bees have been sampled for mites. Many mites were also obtained through field collecting in different countries and via a network of collaborators.

Coauthors are Dr. Ronald Ochoa, USDA-Agricultural Research Service (ARS), Systematic Entomology Laboratory, Beltsville, Md. (a former postdoctoral fellow of OConnor’s);  Dr. Gary Bauchan, USDA-ARS, Electron and Confocal Microscopy Unit, Beltsville, Md.; Amanda Redford and Julia Scher, USDA APHIS, Fort Collins, Colo.

Compiled by Gail Kuhnlein