If you are one of the hundreds, if not thousands, of people who got to watch Jerry Seinfeld lend his voice to the lovable Berry B. Benson in The Bee Movie, you’re probably aware of the massive ecological affect bees have on the environment. But in case you’ve been living under a rock, you should know that bees, honey bees and bumble bees included, are responsible for pollinating more than a third of the food we shove into our mouths. In case you’re more of a numbers person, that means bees rake in about 1.2 billion dollars for people in just the US alone. And if you already knew this, you’re probably also aware of the fact that bees have been declining at pretty alarming rates, probably for multiple reasons. For bumble bees specifically, one of the major causes of mortality is the spread of pathogens from captive-bred bees to wild bees.

bumblebee

Wild bumblebees may be contracting diseases from captive bees. Photo courtesy of University of Illinois at Urbana.

A study published recently by researchers at the University of Notre Dame documents the results of a sampling of bumble bees in Michigan for the fungus known as Nosema bombi. This nasty pathogen is found in the gut and excretory organs of bees and has major negative consequences in terms of individual fitness. Bees infected with Nosema bomi have higher death rates, lower reproductive success, and when they do manage to reproduce, often have deformed offspring. Researchers at Notre Dame set out to see if bees in Michigan were infected with Nosema bombi, and if so, wanted to know if the use of pesticides on farms made them any more susceptible to it. They captured 232 bees in total from 9 different farm sites.

The good news is that none of the bees they sampled were infected with Nosema bombi, which is an encouraging sign for the bumble bee population of Michigan. The bad news, from a scientific perspective, is that the researchers did not get to test their hypothesis regarding the use of pesticides on farms and infection rate of bumblebees. We can all breathe a sigh of relief for the bumblebees in Michigan, but that doesn’t mean we should let our guard down. Two to four percent of bumblebees in North America have been infected by Nosema bombi, including bees in states neighboring Michigan. This study suggests that we need to utilize the time we have to find out more about the pathogens and other factors affecting bees, and in the meantime hope those in Michigan stay safe.

Article:

Skuse, B., Phillippi, A., & Batchelder, E. (2019). The Absence of Nosema bombi in Bumblebees (Bombus spp.) on Farms in Michigan. The American Midland Naturalist, 182(2), 270+. Retrieved from https://envoy.dickinson.edu:8439/apps/doc/A605414962/GRNR?u=carl22017&sid=GRNR&xid=2d010e7a