The nests of most birds harbour fleas and other parasites, which remain to infest young birds that hatch the following year. We recommend that old nests be removed in the autumn, from August onwards once the birds have stopped using the box.
Maintaining your box
Use boiling water to kill any remaining parasites, and let the box dry out thoroughly before replacing the lid. Insecticides and flea powders must not be used.
Unhatched eggs in the box, can only be removed legally between August and January - and must then be disposed of.
If you place a small handful of clean hay or wood shavings (not straw) in the box once it is thoroughly dry after cleaning, small mammals may hibernate there, or birds may use it as a roost site.
It is quite normal for a few eggs to fail to hatch, or for some young to die. Blue and great tits lay up to 14 eggs to allow for such losses. Cold weather and food shortage may lead to nest desertion, or to only the strongest young surviving. The death of one parent or interference from animals or humans may also cause desertion.
Avoid inspecting nestboxes in use, however tempting it may be to take a peek! Simply watch and enjoy from a distance. Only open it up if you've got appropriate skills and experience and are taking part in a monitoring project, such as the BTO’s Nest Record Scheme.If you want to see the chicks as they grow, you could consider installing a nestbox camera before the breeding season starts.
Good hygiene is particularly important during the summer months. The warmer weather can make food go off quicker, and can provide ideal conditions for harmful bacteria.
Monitor your food supply carefully. If the food takes days to clear, reduce the amount of food you're offering. Use a birdtable or hanging feeders. A ground feeding tray is preferable to putting food directly on the ground because it's easier to keep clean. Food on the ground should all be eaten before nightfall. Rats are attracted to leftover food and often carry diseases, which can affect birds or humans.
Keep your bird tables and surrounding areas clean and free from droppings or mouldy food, which can provide breeding grounds for parasites and bacteria. If large amounts of droppings have accumulated, they should be cleared and burnt and the ground cleansed with a disinfectant.
Clean and wash your bird table and hanging feeders regularly (ideally, using a 5% disinfectant solution), and move feeding stations to a new area every month to prevent droppings accumulating underneath.
Water containers should be rinsed out daily, especially during the warmer months, and allowed to dry out before fresh water is added. Droppings can accumulate in bird baths.
Personal hygiene is also important. Don't bring your feeders into your house to clean them - do it outside, using separate utensils. Wear gloves when cleaning feeders and bird tables, and particularly if you need to handle a sick or a dead bird in your garden. Always wash your hands when you've finished.