Expert Insight

• Reporting the birds in your birdhouse can help protect endangered species.Female Tree Swallow (tachycineta bicolor) in a birdhouse image by Steve Byland from Fotolia.com
  
  According to the Cornell Lab of Ornithology, the most effective way to understand the causes of and solutions for declines in species is monitoring. By checking the inhabitants of your birdhouse and participating in a bird count such as Cornell’s NestWatch program, scientists can track reproductive success for all North American breeding birds.
  
  

How to Check

• Watch your birdhouse for activity before checking.Mother Tree Swallow (tachycineta bicolor) And Baby image by Steve Byland from Fotolia.com
  
  Listen and watch the birdhouse for about 30 minutes to see whether there’s any activity. If you do hear baby birds, knock gently on the birdhouse, open it and look inside quickly. Remove any gnats, moth, ants or other parasites and close the box. If your birdhouse opens on the side or from the front, be aware that a baby bird could escape when you are conducting the inspection. If this occurs, gently put the bird back into the nest. According to the U.S. Fish & Wildlife Service, birds have a weak sense of smell and therefore will not reject the baby.
  
  

Keeping Other Birds Out

• Starlings and house sparrows should be removed from your birdhouse.starling image by Nadezhda Bolotina from Fotolia.com
  
  House sparrows and starlings will aggressively take over a birdhouse and often destroy the eggs or kill baby birds. If you find these birds have set up housekeeping in your birdhouse, throw away the nesting material and continue to check the birdhouse every day. You may have to move the birdhouse if they continue to invade. These birds are not a protected species, and it is acceptable to remove their eggs.
  
  

Checking for Animal Predators

• Squirrels can rob a birdhouse of baby birds.squirrel image by Mariusz Blach from Fotolia.com
  
  Regularly inspect your birdhouse for signs of invaders such as raccoons, opossums and squirrels. If the hole on the birdhouse seems larger, a red squirrel might be attempting to secure the house for itself or be hunting the baby birds. Use sheet metal around the hole to keep squirrels away. Opossums and raccoons are adept at reaching inside birdhouses and extracting birds and eggs. Secure an inverted cone to the pole support to discourage these animals.
  
  

Considerations

• Bluebirds are drawn to birdhouses.Male Eastern Bluebird (Sialia sialis) on a stump image by Steve Byland from Fotolia.com
  
  About 85 species of North American birds are cavity nesters, and about 35 of these will use a birdhouse. The most common inhabitants of backyard birdhouses are bluebirds, titmice, bluebirds and wrens. Cardinals, doves and orioles will not use a birdhouse. Some birds that do not nest in birdhouses will use them as protection during the winter.