As nesting season approaches, calcium consumption becomes more important. In the spring, food and calcium availability can determine the total number of eggs that a female can lay. Eggs that lack the proper amount of calcium can have shells that are too thin and break or embryos that die due to excess evaporation through the thinner shell. Chicks also require extra calcium for growing bones. If given a choice between two foods that are identical in every respect except calcium level, young birds and laying females will select a calcium-adequate food more frequently than a calcium-deficient one.
How can I provide my birds more calcium?
Ask for the purple bag. You can offer Wild Birds Unlimited’s No-Mess NM CD. It is sunflower seed with No-Messy shells, Calcium and Diced Peanuts. The hulled sunflower seed is for all the seed eating birds. The chopped peanuts is for all the bug eating birds and the calcium for all the feeder birds. The source of calcium is from finely ground and easily consumed oyster shells or limestone. This also gives them a source of grit, something else birds need to digest food.
You can also offer your wild birds crushed eggshells. Eggshells are about 95% calcium carbonate.
Learn more about serving crushed eggshells: http://recycle-eggshells.html
Learn more about the Lab’s research on acid rain and its effects on breeding birds: http://songbird-population-declines-linked-acid-rain