As you spend time with your bees -- doing hive inspections and observing their behavior in general, you learn to gauge their mood. Let’s say that your colony is typically mellow, but suddenly, their mood has changed. It’s as if someone has taken your nice bees and exchanged them for their mean ones. What is going on? What has caused your normally gentle colony to become aggressive and difficult to manage?
First of all, unless the colony has become Africanized, as a rule, bees are not aggressive. Instead, most honeybees are defensive — they will not attack unless they feel threatened. But when you’re being attacked by a colony of angry bees, whether you want to use the word “defensive” or “aggressive,” it matters little as bees pelt your protective gear. Hopefully, you’re wearing a hat and veil, at minimum, if and when it does occur. But to keep things simple, we’ll go with the word “aggressive,” because that’s what it feels like.
Reasons Bees Become Aggressive
There are many reasons why a normally gentle and calm colony can become cranky and difficult to work with. Let’s take a look at those reasons now.
1. Nectar Dearth When we talk about problems with the hive, it seems that the term 'nectar dearth' keeps popping up, and with good reason. Bees spend the warmer months of the year stocking up for the cold winter months when they aren’t able to get out of the hive and forage. When a nectar dearth occurs, resources (pollen and nectar) are scarce. Without a continual supply of incoming resources, the colony becomes stressed. Some bees resort to robbing activities to bring resources into the colony. To save available resources, drones may be evicted. The queen may even stop laying eggs. Most parts of the country go through a nectar dearth at some point during the warm months, maybe even more than once. A nectar dearth can last for several weeks, or it may only last for a few days. However long it lasts, your colony may be a little testier than usual until it has passed.
2. Hot Weather Detrimentally Affects Bee’s Mood Aside from bringing about nectar dearths, hot weather causes stress to colonies in other ways as well. As the workers are diligently working to forage for nectar and pollen, the hot weather pulls some workers away from their normal activities. Some bees are working to ripen the honey. Others that would normally be out foraging have to spend a good portion of the day gathering water as they work hard to ventilate and cool the hive. The hive may be at its peak with large populations of bees, resulting in lots of eggs and larvae to care for. All this extra work can cause stress, making the bees a little grumpier than usual.
3. Bigger Colonies May Be More Aggressive Larger colonies have a tendency towards being more aggressive and defensive than their smaller counterparts.
4. Robbing Activities Leads to Aggression We just spent the last four weeks talking about robbing activities and how bees on both sides of the battle are willing to fight to the death. That's a lot of aggressive bee behavior. Many insects love the sweet taste of honey, including ants, wasps, hornets, bumblebees and other honeybees. Given the opportunity, they'll do what they can to satisfy their sweet tooth. The resident bees don’t just stand by and allow these robbers to come in and steal their winter survival resources. When the robbing begins, the guard bees release an alarm pheromone. This tells the rest of the hive that there’s a threat and that it’s time to fight ... to the death. If you happen to approach the hive when a robbery or robbery attempt is going down, especially without protective gear, you’ll find yourself on the receiving end of the bee’s defensiveness and aggression.