Think before you swat: How wasps mark you as a target for the group

It’s a reflex we all have, and it's a difficult one to fight — but experts say swatting at wasps can actually make things worse.

According to Dr. James Tansey, an entomologist with the Saskatchewan Ministry of Agriculture, wasps don’t just sting in the moment — their defensive attack also involves chemical communications with others of their species nearby.

“They actually produce an alarm pheromone, which has been demonstrated in at least one of the yellowjacket species. So crushing a worker female, if she’s stinging, can elicit an attack response in other nearby yellowjackets, especially if they’re related.”

Even more surprising, Tansey says, is how long the scent can linger.

“They also tag you with a pheromone once you’ve been stung. You can carry this ‘threat marker’ for 8 to 12 hou