The flies this summer seem to be biting more than the mosquitos. In fact, we've been hearing from our listeners about the nuisance the biting families of flies are causing in the area, including for the dogs at the Weyburn Humane Society animal shelter.

Many of these flies release a numbing anti-coagulant when they bite, which means they have already had a feast before you even notice the painful, burning sensation, which can sometimes leave quite a mark on people, pets, and livestock.

We asked Dr. James Tansey, Provincial Insect and Vertebrate Pest Management Specialist for the Saskatchewan Ministry of Agriculture, for some tips on how to help deter these pests. 

"DEET is effective for all of these biting flies, and it can also be effective for ticks as well, so that's a really good consideration," he noted. "There's also a product called Lemon eucalyptus for those who might have a DEET sensitivity or concerns about DEET. So in my experience, that product has been very effective. I can't say for ticks, although I have seen some data to indicate that it's efficacious for dissuading ticks."

He noted the lemon eucalyptus is a natural product for those who favour that, "however, everything comes with a bit of an asterisk. It does still pack a bit of a punch. So you want to be careful around your nose and around your eyes. It'll sting if it touches mucous membrane, so you apply that much like you would a Deep Woods OFF." 

Tansey said there are also garments available for those who need them.

"You can get permethrin-treated permeated clothing, and I know there are some retailers in Saskatchewan that sell that," he said. "Permethrin is a Group 3 insecticide, with low mammalian toxicity, but it has a really profound effect on some of the biters that you might encounter, and we'll dissuade them from landing on you. So you can buy shirts and pants that are permeated with that insecticide."

How do citronella-based products stack up against the rest?

"I haven't seen convincing data that those citronella coils are all that efficacious, even for mosquitoes."

He said the H-Traps, commercially available in Saskatchewan, work well for catching biting flies such as horse flies, deer flies, and stable flies. 

"I purchased one recently, have it set up on my place, and it works very well, with not too much in the way of bycatch. So of course, people don't want to be catching moths and bumblebees and that sort of thing. I've also seen very little in the way of bycatch with it, but it does seem to be a pretty good trap for catching horse flies."

Tansey doesn't, however, recommend the use of 'bug zappers'

"The reason being is, although we do have night active mosquito species, most of the biting flies are going to be day flyers like the horse flies and deer flies," he explained. "They're only active during the day, so once it's dark, those bug zappers are active. They're just putting out ultraviolet light mixed with visual light, of course, and that's just a general-purpose attractant to a broad assemblage of insects, so really, you're killing beneficials, you're killing neutrals."

"It really is kind of carnage for the insect world where you might be inflicting some damage on some species where you don't want to, in addition to really being only moderately attractive to night flying mosquito species." 

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