To help honey bees survive the winter in the Pacific Northwest, you can:
Provide enough food
Make sure the hive has enough honey and pollen to survive the winter. You can feed the bees syrup in the fall, and a pollen supplement or substitute if there isn't enough pollen in the frames. After October, you can switch to feeding the bees dry sugar or a partially converted sugar source like fondant or drivert sugar.
Reduce moisture
Use shims to prevent the top cover from pressing against the hive box, allowing damp air to escape. You can also remove the propolis seal that glues the covers to the hive box.
Reduce the entrance
Use the narrowest opening on the entrance reducer to keep out wind and reduce the space the bees need to defend. You can also protect the entrance from mice with a mouse guard.
Control mites
Varroa mites can weaken bees and make them more susceptible to disease. You can treat the bees with Thymol or Oxalic Acid to reduce the infestation
Avoid moving the bees
If it's very cold, wait to move the bees because they might not be able to crawl back in and could die.
Honey bees don't go dormant in the winter, but instead stay active inside the hive, eating honey and shivering to generate heat. However, bees that fly during mild winter weather are less likely to survive until spring.
