🐝 Two-Queen Colony Systems and Double Screen Boards

About this simulation

A two-queen system stacks two full, independent brood colonies — each with its own laying queen — in a single vertical hive tower, separated by a double screen board: two layers of fine wire mesh with a small ventilated air gap between them. The mesh blocks bees and queens from ever touching, so neither queen can be killed by the other, but it still lets warmth, scent and colony vibration pass through, so the two units behave, thermally, almost like one large colony. Above both brood nests sits one shared honey super that either colony's foragers can fill, roughly doubling the flying force contributing to a single crop of honey without doubling the footprint of hives in the apiary.

How it works

• The double screen board is the safety feature: remove it and the two queens can meet directly through a torn or missing mesh, which almost always ends in a fatal queen fight and collapse back to a single-queen colony.
• Entrance layout matters because young orienting bees learn the location of "their" entrance. Facing the two entrances in opposite directions (front and back, or 180° apart) keeps each colony's flying bees finding their own queen; stacking both entrances the same way increases accidental drifting between colonies.
• Drifted bees are not necessarily lost — worker bees are usually accepted into either colony — but heavy drift can quietly shift population and stores from one colony to the other, undermining the balance the system depends on.
• Because the mesh screen prevents direct contact, both queens keep laying independently below, while their combined foraging force is funnelled up into one shared super, which is where the yield advantage of the two-queen method comes from.

Controls

• Double screen board fitted — remove it to see what happens without the mesh separating the two queens.
• Entrance layout — compare opposite-facing entrances against both entrances stacked the same way.
• Forager traffic — how many bees per second are returning home across both colonies.
• Shared honey super open — toggles whether the super above the screen is accessible to both colonies' foragers.
• Show pheromone zones — toggles the translucent scent-field markers around each queen.
• Drag to rotate the hive stack, scroll to zoom.

Did you know?

Two-queen colonies were popularised in North American commercial beekeeping in the mid-20th century specifically to boost honey yield per apiary site: two queens laying at full pace can build up a far larger combined foraging population than one queen ever could, and that extra workforce is what fills the shared supers so quickly.