Africanized Bees in Arizona: Why a Swarm on Your Wall Is Not a Do It Yourself Job

A bee swarm on your wall in Arizona is not a do it yourself job because every honey bee colony in the state below about 5,000 feet should be assumed to be Africanized, and an Africanized colony responds to a hardware store spray by sending out hundreds of defenders that chase for a quarter mile. The swarm may leave on its own within a day or two; if it does not, or if it is near a door, a pool or a school, it needs a suited technician.

What Africanized Bees Are

Africanized honey bees are a hybrid of the European honey bee and an African subspecies that escaped from a breeding program in Brazil in the 1950s and spread north, reaching Arizona in 1993. They are now established across the whole state below roughly 5,000 feet: the Phoenix metro, Tucson, Yuma, Lake Havasu City, Bullhead City, Casa Grande and Sierra Vista. Flagstaff and Prescott sit high enough that pressure drops off.

They look identical to European honey bees. Only a lab can tell them apart. The venom is the same per sting. What is different is behavior. An Africanized colony guards a much larger zone around the hive, responds to a disturbance with 10 times as many defenders, stays agitated for hours, and pursues a person or animal for hundreds of yards. A dog tied in a yard, a child on a bike, a landscaper with a mower and a homeowner with a can of spray are the typical victims, and deaths in Arizona have involved all four.

Swarm Versus Hive

The first thing to figure out is which one you have, because they are handled differently.

A swarm is a ball of bees, from softball to basketball size, hanging from a branch, a block wall, a mailbox, a patio beam or the side of a car. It is a colony in transit: the old queen and half the workers left the parent hive and are resting while scouts look for a new home. A swarm has no comb and nothing to defend, so it is usually calm, and it often moves on within 24 to 48 hours. The problem is where it goes next, which is frequently the nearest wall void, chimney, shed or irrigation box.

An established hive is bees going in and out of one spot: a weep hole, a gap under the stucco, a water meter box, an irrigation valve box, a shed wall, a chimney, a hollow saguaro or a block wall cell. Behind that entry is comb, brood and honey, and the colony will defend it. A hive that has been in a wall for a season has 20 to 40 pounds of comb and honey in the cavity.

Why Spraying It Yourself Goes Wrong

The hardware store wasp spray reaches the bees at the entrance and nothing else. The colony inside reacts to the attack by pouring out, and now there are thousands of agitated bees in the yard with nowhere to go. The person spraying is stung first, then whoever is nearby. Even when the spray kills the bees at the entrance, the comb is still in the wall. In summer heat above 100 degrees it melts, honey runs down inside the drywall, ants and roaches come for it, the wall stains, and the scent draws the next swarm to the same spot within weeks.

Sealing the entrance shut is the other homeowner mistake. The bees do not die, they chew through the drywall into the house.

What a Technician Does

1. Clears the area of people and pets and assesses whether it is a swarm or a hive, where the comb is, and who is nearby.

1. Suits up with a full bee suit and veil. Nobody does this work in a t shirt.

1. Treats the entrance and the void with product applied into the cavity so the colony is dead before the wall is opened.

1. Opens the wall or box and removes every piece of comb and honey, which is the step that makes the fix permanent.

1. Seals the opening and masks the scent so a new swarm is not drawn to the same cavity.

1. Comes back to confirm no returning bees and no missed comb.

Wasp work is similar but simpler: paper wasp nests under eaves are treated at dusk when the wasps are on the nest, and yellowjacket ground nests are treated at the hole and left for 24 hours before the hole is filled.

What to Do While You Wait

Keep everyone inside and keep pets in. Do not mow, use a blower or run a pool pump near the bees, since vibration sets them off. Warn neighbors on either side. If bees are already attacking, get into a house or a car, cover your face, and keep moving away; do not jump in the pool, they wait above the water. Call 911 for anyone stung many times, anyone with a known allergy, anyone stung in the mouth or throat, and any child or older adult with more than a few stings.

FAQ

Will the swarm on my wall leave by itself? Often, within a day or two. If it is still there after 2 days, or it is near a door, a walkway, a school or a pool, it is worth a call, because the place it picks next may be your wall.

Can a beekeeper just take them? Some beekeepers collect hanging swarms. Most will not remove an established Africanized hive from a wall, and a colony in a structure in Arizona is a pest control job with a suit, a treatment and comb removal.

Why do bees keep coming back to the same spot on my house? Because comb was left in the wall after a previous treatment. The scent of old comb draws the next swarm. Opening the wall and removing it stops the cycle.

If bees are going in and out of a weep hole or hanging from the block wall, call Green Ninja Pest Control for bee and wasp removal and keep the family and the dog inside until the technician arrives.