(NaturalNews) Commercially bred bees used pollinate greenhouse crops may be spreading diseases to wild populations, according to a study conducted by researchers from the University of Toronto and published in the journal
PLoS ONE.
Bee populations have been collapsing across North America in recent years, alarming not only scientists but also the food industry. Honeybees alone pollinate 130 different food crops, responsible for $15 billion worth of food and ingredient revenue each year.
In the current study, researchers observed that commercially bred bumblebees used to pollinate bell peppers, cucumbers and tomatoes in southern Ontario were regularly flying in and out of the greenhouses where the
crops were kept. They then constructed a mathematical model to predict what it would look like if the commercial
bees were spreading infections to wild bumblebees.
The model predicted that the rate of
infection would slowly increase among wild bees living near the greenhouses over the course of weeks or months, until reaching a critical threshold leading to widespread rapid transmission affecting nearly all bees in the area. Rates of infection would drop off, however, with increasing distance from the greenhouses.
The researchers then captured a random sample of wild bumblebees from around the greenhouses and conducted thorough tests for pathogens. They found that infection rates of a certain intestinal parasite (Crithidia bombi) matched the pattern predicted by the model.
"All of the different species of bumblebees that we sampled around greenhouses showed the same pattern: really high levels of infection near greenhouses and then declining levels of infection as you moved out," researcher Michael Otterstatter said. "It was quite obvious that this was coming from the greenhouses and it was a general adverse effect on the bumblebees."
Approximately 50 percent of wild bumblebees in the vicinity of the greenhouses were infected with Crithidia bombi. Levels of other parasites were normal.
Sources for this story include:
www.reuters.com.
Have comments on this article? Post them here:
people have commented on this article.
Email this article to a friend
Share this article on: 
Now Available from 
