What Do Honey Bees Do on a Cold, Wet, and Windy Day in Australia?
Beekeeping in a variable climate like Australia, especially in a region like Port Sorell, Tasmania, means preparing for all kinds of weather. While we often think of bees buzzing on sunny days, their survival hinges on remarkable adaptations to less favourable conditions. When the Southern Hemisphere winter brings cold, wet, and windy days, your European honey bees (Apis mellifera) aren't simply 'doing nothing'. They're engaged in a complex, collective effort to ensure the survival of the entire colony.
The Winter Cluster: Bees' Natural Defence Against the Cold
On days when the temperature drops, especially below 10°C, European honey bees don't hibernate individually. Instead, they form a remarkable "winter cluster." This isn't just a random pile of bees; it's a highly organised, dynamic structure. Bees on the outer layer of the cluster form a protective insulating shell, vibrating their flight muscles to generate heat without actually flying. The bees on the inside of the cluster are warmer and less active.
As the outer layer cools, bees from the warmer core gradually move to the periphery, rotating positions to ensure no bee freezes. This continuous, slow-motion dance allows the colony to maintain a remarkably stable temperature within the cluster, typically around 20-30°C in the outer layers and up to 35°C at the core where the queen and any developing brood might be. This intricate social thermoregulation is vital for their survival during prolonged cold snaps, common in Tasmanian winters.
Maintaining Optimal Hive Temperature: A Collective Effort
The bees' ability to control their internal cluster temperature is a marvel of nature. Their primary goal is to keep the queen warm and ensure any existing brood can develop. During active brood rearing, the brood nest area is maintained at a precise 33-36°C. Even on the coldest, wettest days, the cluster will work to achieve this.
Muscle Vibrations: Individual bees vibrate their flight muscles, generating heat. This is a significant energy expenditure.
Honey Consumption: To fuel this heat generation, bees consume their stored honey. The rate of consumption increases with colder temperatures. This is why adequate honey stores are critical for colony survival over winter.
Cluster Density: The tighter the cluster, the more efficiently heat is conserved. On extremely cold days, the cluster will contract significantly.
The Importance of Cleansing Flights
Even on a series of cold, wet, and windy days, bees still need to expel waste. Unlike many creatures, honey bees are remarkably fastidious and generally do not defecate inside the hive. This means that after a prolonged period of confinement due to adverse weather, they will take what's known as a "cleansing flight."
A cleansing flight is a short, rapid flight out of the hive for defecation. This typically occurs on the first brief period of sunny, relatively calm weather where temperatures rise above around 10-12°C. You might observe a sudden flurry of activity around the hive entrance, with many bees flying out, defecating, and quickly returning. It’s a crucial activity for hive hygiene and bee health. If bees are unable to take cleansing flights for extended periods, they can develop issues like dysentery, which weakens the colony.
Ideal Conditions for a Cleansing Flight:
Temperatures above 10-12°C
Minimal wind
No rain
Presence of sunlight (often triggers the activity)
Food Consumption During Inactivity
While confined to the hive, bees rely entirely on their stored resources. Honey is their fuel, and pollen provides essential proteins and nutrients. During a cold, wet, and windy period, their activity outside the hive is minimal or non-existent, meaning no fresh nectar or pollen is coming in.
The colony consumes honey to generate heat and maintain the cluster. The queen continues to lay eggs (though at a reduced rate during colder months), and larvae need pollen for development. A healthy colony going into winter in Australia will have ample honey and pollen stores to see them through. Beekeepers at Frogmouth Ponds consistently monitor honey stores, ensuring our bees have abundant reserves to thrive during these challenging times.
What This Means for Australian Beekeepers
Understanding these behaviours is paramount for Australian beekeepers, particularly those in Port Sorell, Tasmania, where winter conditions can be quite severe.
Leave Ample Honey: Ensure your hives have sufficient honey stores going into autumn and winter. This is the bees' lifeblood.
Minimise Disturbances: Avoid opening your hives during cold, wet, and windy conditions. Disrupting the cluster can cause significant stress and heat loss, potentially leading to colony collapse.
Monitor Entrances: Ensure hive entrances are clear of debris or dead bees, allowing for cleansing flights when conditions permit.
Observe from a Distance: Observe your hive from a distance. Signs of activity during a brief sunny spell indicate a healthy colony taking cleansing flights. Lack of activity over extended periods may warrant closer inspection on a warmer day.
By respecting the bees' natural instincts and providing the right environment, you can help your European honey bee colonies not just survive, but thrive through Australia's coldest, wettest, and windiest days, emerging strong and ready for the spring nectar flow.
