By NIKKI ROTHWELL Special to the Record-Eagle
Traverse City Record-Eagle
---- — During spring in the fruit business, our thoughts always turn to pollination.
First, we hope that our “hired help,” honeybees, will be in good condition to pollinate our fruit crops. Unfortunately, honeybees have suffered some setbacks in recent years, and as a result, bee populations have been declining. The new United States Department of Agriculture and Environmental Protection Agency report on honey bee health concluded there are multiple factors playing a role in colony declines: parasites and disease, genetics, poor nutrition, and pesticide exposure. The report finds honeybee health is a complex problem and the declines in healthy colonies are caused by a combination of stressors.
First, parasites are playing a role in honeybee health, which is not a new problem. The Varroa mite is a parasite that can only reproduce in honeybee hives and it is likely the primary cause of colony loss in the United States. These mites attach themselves to the bees, feed off the hemolymph, and can eventually kill a whole bee colony under optimal conditions. Researchers have also documented widespread resistance to the chemicals beekeepers use to control mites in the hive. New virus species have also been found in honeybee hives, and these diseases have been linked to Colony Collapse Disorder (CCD.)
Scientists have identified a need for increased genetic diversity in honeybee colonies. They believe that genetic variation will improve the honeybee’s ability to keep body temperatures stable despite the fluctuations in the surrounding environment. Genetic variation will also help with disease and parasite resistance and improve worker productivity.
Nutrition has also been identified as a problem with honeybee declines. Good nutrition, just like in humans, has an impact on both individual bees as well as colony durability. If bees do not have a nutritious diet, they become more susceptible to disease and parasites. In short, bees need better forage and a variety of plants to support a nutritious diet to improve overall health. To this end, Michigan State University has received a Specialty Crop Research Initiative (SCRI) grant to investigate bee habitats and pastures planted next to agricultural crops to improve pollination services.
Lastly, there needs to be more research to determine the risks posed by pesticides. There are misconceptions circulating about the impacts of pesticides on honeybees, but empirical data are lacking to determine the true relationships between pesticides and honeybee health. More research is warranted in this area in order to make any recommendations or conclusions about the amounts and types of pesticides that may impact honeybee colonies.
Thus, the verdict is still out as to why honeybee populations are declining. However, there is a major commitment by the U.S. government, beekeepers, researchers, growers, and the public to work together to protect our honeybee population. And, we know here in northwest Michigan, our honeybees are working hard to pollinate our fruit crops.
Nikki Rothwell is a Michigan State University Extension district horticulturalist and coordinator of the Northwest Michigan Horticultural Research Station.