Wood Shavings for The Bird House

Cornell Laboratory of Ornithology conducted studies on the success rate of nest boxes being used by Black-capped Chickadees and discovered the following:

• Nest Boxes with wood shavings - excavated 40% to 50% more often than nest boxes without wood shavings
• Nest Boxes with wood shavings - nests were initiated 15% more often than nest boxes without wood shavings

This study shows that species that naturally dig out nesting spots in trees are more likely to use a manmade nest box if it’s filled with wood shavings. The shavings are packed tightly inside, extending up past the entrance hole. If you want to attract Black-capped Chickadees or Red-breasted Nuthatches, adding wood shavings to the nest box can increase the chances of successful nesting.

Not all wood shavings are suitable for use in a nest box. Here’s a quick rundown of the most common types available for purchase.

Wood Shavings

Any wood shavings used should be untreated.

Aspen vs Pine vs Cedar

• Aspen shavings are recommended.
• Lowest amount of Volatile Organic Compounds (VOC).

• Pine shavings are a better option than cedar.
• VOC’s are not in as high a concentration as cedar.

• Cedar shavings are not recommended.
• Very high in VOC’s
• When cedar is turned into shavings, much more surface area is exposed, so these compounds are released into the air more readily than from solid boards.
  
• Birds have extremely sensitive respiratory systems.
  
• Airborne chemicals (VOC’s) affect them more quickly and at lower concentrations.
  
• This risk is higher in enclosed spaces like nest boxes
  

Note:

Cedar nest boxes are safe:

• VOCs are slow‑releasing from solid wood
• Outdoor airflow keeps concentrations far below irritation thresholds.
• Birds evolved alongside aromatic woods and tolerate them well in structural form, not as bedding

 Aspen wood shavings