Why Wild Birds Need Foods with Calcium

Calcium is the most challenging mineral that birds need because of the extreme changes in periods of demand (like egg laying and chick development) and because many foods are likely to be deficient in calcium.

The amount of calcium in the seeds and insects supplied by natural diets of many birds is inadequate for the production of eggs and they must seek calcium-rich foods as a supplement. Birds that lay more than 2-3 eggs must markedly increase their calcium intake during the days the eggs are laid.

If adult birds don't eat enough calcium they may not lay as many eggs as normal. Without enough calcium the eggs they lay will have thinner than normal shells causing the embryos to dry up due to excess evaporation

In growing chicks, a calcium deficiency causes skeletal abnormalities including rickets, lameness, enlarged and painful joints and misshapen bones.

If available, birds often consume concentrated calcium sources, especially in the evening as they are forming eggs overnight to lay them the next day. So, watch for increased evening feeder activity by female birds during their nesting time if you are offering calcium-supplemented foods. Nesting season for most backyard feeder birds run from April through July.

Calcium carbonate is the mineral found in wild bird foods. Calcium carbonate is quickly and efficiently broken down in the digestive tract to be easily absorbed and used by the bird. So, pass the mile and cookies. Happy Birdfeeding!

(Kathy and her husband, John, own and operate the Wild Birds Unlimited, located in Billings. She is a Certified Bird Feeding Specialist, and is past president of the Yellowstone Valley Audubon Society.)