aggressive bees in michigan

Aggressive Bees in Michigan: How to Identify and Avoid Them

Bees play an important role in Michigan’s ecosystem and agriculture but some species can become aggressive and pose a risk to humans. Understanding which bees tend to be more defensive, why they act aggressively and how to avoid provoking them is key to coexisting safely.

The Most Aggressive Bee Species in Michigan

According to entomologists, the most aggressive bee species commonly found in Michigan include:

• German Yellowjackets (Vespula germanica)
• Bald-Faced Hornets (Dolichovespula maculata)
• European Hornets (Vespa crabro)
• Honey Bees (Apis mellifera) – Africanized subspecies

These species are more likely than other bees to sting when their nest or food source is threatened. Their stings can be painful and repeated stings potentially dangerous.

German yellowjackets are small, black and yellow wasps that build papery nests. They can become very aggressive in late summer when colonies reach maximum size.

Bald-faced hornets are large, black and white wasps that make football-sized gray paper nests high in trees They will vigorously defend the nest if disturbed

European hornets are non-native wasps with brown and yellow markings. They build large paper nests and will sting repeatedly when threatened.

Africanized honey bees, also called “killer bees,” are an aggressive hybrid derived from an African subspecies. They’ve gradually spread northward into southern states.

What Triggers Aggressive Behavior?

Bees become defensive when they perceive a threat to their colony, food source, or selves. Some key triggers include:

• Vibrating or disturbing a nest: Bees interpret vibrations as an attack on the nest.

• Swatting: Rapid movements near bees trigger a defensive response.

• Blocking food sources: Guard bees will sting to protect a food source.

• Trapping: Accidentally trapping a bee elicits stinging behavior.

• Body heat and sweat: Bees are attracted to these, so can inadvertently fly inside clothing.

• Carbon dioxide: When we exhale this causes excitement and alarm in bees.

Aggressiveness also increases late in the season as colonies enter “defensive mode” to protect queens and food stores for winter. Africanized honey bees are genetically predisposed to heightened aggression.

Avoiding Bee Aggression

The best way to prevent aggressive behavior is to avoid antagonizing bees in the first place. Helpful tips include:

• Give nests a wide berth and avoid disturbing them. Bald-faced hornet nests should not be approached within 15-20 feet.

• Stay calm and move slowly if bees start buzzing around. Don’t swat or make sudden movements.

• If a bee lands on you, gently brush it away or slowly walk away.

• Don’t wear strong perfumes, scented lotions or brightly colored clothing outdoors.

• Keep food and drink covered when eating outside since sweet items attract bees.

• Check for bees inside clothing or umbrellas before using them.

• Be cautious drinking from open soda cans which can trap bees inside.

• Avoid mowing or trimming vegetation when bees are most active during warmer midday hours.

• Have a professional remove problem nests whenever possible, especially those of bald-faced hornets or Africanized honey bees.

What to Do if Stung

If stung, the key steps are:

• Use a scraping motion to remove the stinger immediately with a fingernail or card. Avoid squeezing the stinger which releases more venom.

• Wash the sting site with soap and water and apply an ice pack to reduce swelling and pain.

• Monitor for signs of systemic reaction, including hives, difficulty breathing, or swelling of the face or throat. Seek medical attention immediately if these develop.

• Use over-the-counter analgesics like acetaminophen or ibuprofen to relieve pain.

• Apply hydrocortisone cream containing 1% lidocaine to further reduce pain, swelling and itching.

For most bee species, stings produce only localized pain, swelling and redness lasting a few hours. Multiple stings or stings to sensitive areas like the head or neck can be more dangerous, especially for young children or those with allergies. Seek medical care if needed.

With proper precautions, we can safely co-exist with even the more aggressive bee species that call Michigan home. Being aware of their nesting behaviors, not inadvertently threatening hives, and removing problem nests are key to avoiding negative encounters. Staying calm, still and gently removing any bees that do land on you can also prevent stings. Taking sensible precautions allows us to respect the important pollination role of bees while protecting human health and safety.