Wasp Season Has Arrived — Help Us Map Active Nests
If you’ve been hiking recently, you’ve probably noticed them - and they are fierce this year.
That’s not just your imagination. According to BC pest experts, a relatively mild winter followed by an early, warm spring allowed more queen yellowjackets to survive hibernation and establish new colonies. With a longer growing season, those colonies have had more time to expand, resulting in larger, more defensive nests by late summer.
Why Are They So Aggressive?
The yellowjackets we encounter in Southwest BC are ground-nesting wasps. Their nests are often hidden beneath roots, rocks, logs, or vegetation beside the trail. You may not see the nest until you accidentally step near it, triggering dozens of wasps to defend their colony. Unlike bees, yellowjackets can sting repeatedly.
By August and September, a single colony may contain hundreds to thousands of worker wasps, all protecting the nest and searching for food as natural food sources become scarce.
What Happens If You’re Stung?
Most stings cause:
· Pain
· Redness
· Warmth
· Swelling
· Itching
These symptoms usually improve over the next few days.
Some people experience a large local reaction, where swelling extends well beyond the sting itself. For example, a sting on your leg may cause your entire calve to swell.
More serious reactions are uncommon but can occur.
Signs of Anaphylaxis
· Difficulty breathing
· Swelling of the lips, tongue, or throat
· Widespread hives
· Dizziness or fainting
This is a medical emergency.
An EpiPen is the only first-line treatment for anaphylaxis. If you’ve been prescribed one, always carry two when heading into the backcountry and call 911 immediately after using one.
What Should You Carry?
For most hikers, consider packing:
· A non-drowsy antihistamine such as Claritin or Reactine
· 1% hydrocortisone cream to reduce itching
· Basic pain medication if needed (Advil / Tylenol)
Remember, antihistamines can help relieve itching and swelling, but they do not treat anaphylaxis.
Don’t Forget Your Dog
Dogs often find yellowjacket nests before we do. A sting to the face or inside the mouth can cause significant swelling.
If your dog develops facial swelling, difficulty breathing, repeated vomiting, or collapses after a sting, seek veterinary care immediately.
Help Protect Other Hikers
If you discover an active wasp nest along a trail, please report it.
Report it to Lions Bay Search and Rescue
Email info@lbsar.com with:
· Trail name
· Approximate location
· A photo, if it’s safe to take one
· GPS coordinates, if available
We’ll post the location as a trail hazard to help warn other hikers on All Trails.
Add it to Wasp Watch
Visit wasp-watch.com and pin the nest on the interactive map. Community reports help hikers identify active nests before they unknowingly walk into them.
A simple report today could prevent the next hiker—or their dog—from having a very painful day on the trail.