Black flies have been plaguing us recently and I see that they are a hot topic of discussion for Ocean City beach goers this week. I did a little research and found that our writer, Tony Russo, addressed this topic almost exactly 4 years ago. Here’s some of the biology of flies and why a west wind bodes ill for beach-goers who are likely to attract the blood-hungry insect. Enjoy — and hope for a change in the wind direction!
Originally published September 9, 2016
Although black biting flies are a rarity on the boardwalk their occasional appearance isn’t unknown, although it always is unwelcome. I spoke with Ginny Rozenkrantz, who runs the lower shore University of Maryland Extension offices. She has a good handle on the fly problem and its (fleeting) solutions.
West wind is a factor
“Whenever you have a land breeze, you have a lot of flies,” said Rozenkrantz. The sea breeze traditionally keeps these flies on the mainland, but without resistance flies have no impediment. In fact, the wind actually helps them to cover larger distances than they normally would cover.
A perfect storm
The deluge of last week brought out the worst in the flies, the larvae of which grow in moving water. Big storms in the fall, as we’ve been having, tend to encourage flies to join in in what the birds and bees are mostly known for. There were a bunch of flies around anyway. It’s been a less-than-great year for Assateague beach goers who don’t really dig the flies, so although Ocean City usually is immune, there already were a ton of flies active before last week’s storm.
Autumn is crunch time for flies
The female flies feed on blood before laying their eggs. All of their biological clocks are ticking at deafening levels. So when given the opportunity they find their food where they can. People on the boardwalk in the still, or westward wind air are a perfect target. Moreover, they look to the untrained eye like normal flies until they’re inflicting an irrationally disproportionate level of pain on your arms and legs.
Technically invincible
When the flies come to Ocean City’s Boardwalk there is no solution but to wait for the wind to change. Most pesticides prevent larvae from maturing, but once they mature there is little to be done. If bug spray is your thing (and it totally is mine, I’ll have the extra DEET version, thanks) use it generously. It works on Assateague, so it ought to work in Ocean City. Beyond that, just be patient and keep your eyes on the flags because when the wind changes it will disperse the flies.