USDA-APHIS Farm Bill Development of Resources for Early Detection of Existing and Emerging Parasites Infesting Honey Bees in Texas
What is Colony Collapse Disorder (CCD)?
- Most worker bees disappear
- Food remains
- Queen bee and a few attendants remain
- Immature and larval bees remain
- Pollination stops
- Honey production stops
CCD occurs worldwide-mainly between 2006-2013. An estimated 10 million beehives have been lost to CCD. $200 billion of crops depend on honey bees for pollination so we need to do everything we can to
Potential Causes of CCD:
- Pesticides (neonicotinoids)
- Infection by parasitic mites (ectoparasites)
- Infection by internal parasites (endoparasites)
- Depredation by ants
- Diseases & loss of disease resistance
- Genetic issues
- Loss of habitat
Most likely CCD is caused by a combination of the above potential causes
TISI Project Goals:
- Conduct a comprehensive baseline survey of privately owned apiaries for pests and parasites of honey bees
- Place traps for small hive beetles and varroa mites
- Use molecular biology techniques to identify:
- Genetic lineages of bees in each apiary
- % Africanization from colonies that display aggressive behavior
- Provide a GIS map of counties affected by Africanized honey bees
- Calculate parasite and pest density
- Report regional distribution of parasites and pests
- In 2015, TISI sampled honey bees from 18 apiaries within 11 counties and 8 ecoregions.
- In 2016, TISI sampled honey bees from 35 apiaries within 22 counties and 10 ecoregions as well as caught feral bees from west Texas (Trans-Pecos ecoregion).
Counties sampled are indicated by symbol
Field technicians visited apiaries to collect samples of honey bees, place traps for small hive beetles, and form connections with beekeepers.
TISI sampled both Top-bar (above) and Langstroth (left) hives and placed small hive beetle traps in either the entrance of the hive, on top of brood frames, or below frames (top-bar hives). We used Beetle barn (Rossman Apiaries, bottom right) and All Beetle traps (insectslimited.com, bottom left).
Some bees were caught “in the wild” using swarm traps (right). Collecting feral (wild) honey bees allows TISI to research if feral bees have different number of pests/parasites than “managed” bees at an apiary.
Dr. Autumn Smith-Herron was able to detect Nosema (right) (Nosema apis), which is a protozoan parasite of adult honey bees that looks similar to grains of rice. Nosema affects the digestive hind gut and causes severe diarrhea and prevents the bee from producing royal jelly (used to feed brood and make new queen bees), resulting in low brood number. This disease usually occurs in spring, so keeping hives well stocked with food and free of other diseases throughout winter helps prevent Nosema infection.
Small hive beetle (SHB): SHB (Aethina tumida)
larvae eat everything inside the comb, defecating along the way causing the honey to ferment and ooze out of the comb. The larvae need to pupate on the ground, so keeping hives on top of concrete or hard-packed earth should help prevent reinfection of a hive. Strong colonies seem to be able to keep this pest under control, but weak colonies may leave the hive entirely. Adult SHB (left) larval SHB (middle).
Varroa mites: (Varroa destructor)
External parasites of honey bees harm both brood and adults, but prefer brood. They suck blood from honeybees which weakens them and shortens their lifespan. Brood may emerge with missing or deformed wings and legs.
If varroa mite infestations are left untreated, they will kill honeybee colonies. Mites will spread from one honeybee colony to another by drifting drones and workers within an apiary.
Early detection of low levels of varroa mite infestations is essential to their management. If one colony has mites, all colonies should be treated to prevent further infestation.
Tracheal mites: (Acarapis woodi) live in the trachea of honeybees and can’t be seen without dissecting the bees (left); however, bees that can’t fly but seem to have working wings are an indication. They also cause K-wing (right). Strong colonies should keep this parasite to a minimum. Tracheal mites invade the airways of the bees so the bees don’t breathe well. This mite is more prevalent in winter because all the bees congregate in the hive and the mite can jump from bee-to-bee in a similar manner as fleas.
This is the only pest/parasite we have not yet found.
Greater Wax Moths: (Galleria mellonella) are a pest species originally from Asia and Europe. Adult left) and larval (middle) moths feed on honeycomb. Adult moths construct webs that entangle bees (right). Larval moths leave foul deposits in the honey so neither the bees nor humans want to consume it.
TISI also promotes Education and Outreach. In June 2016 TISI had an educational booth at the Texas Beekeepers Association summer clinic about the honey bee health research project. We found volunteers to participate in our project by placing small hive beetle traps in their hives and mailing the traps back 3-4 weeks later. Volunteers make our research possible and we would like to thank everyone who has allowed us to sample from their apiary and participated in the beetle trap survey.