Why are my sparrows eating barbecue ashes?? - Via Twitter
calcium. Some songbirds in search of calcium may have started to look in unusual places because pollution has depleted it in the environment.
Another explanation for birds rummaging in charcoals is for grit. The gizzard is an organ found in the digestive tract of some birds and is used to grind up food. A lot of grain eating birds swallow small stones, shells, and sand occasionally to break apart hard seeds as they pass through the ventriculus also known as the gizzard. The grinding stones in the bird's gizzard wear down eventually and pass through the bird but are replaced with new stones the bird swallows.
Finally birds may be looking for any food scraps. While most of our backyard birds visit seed feeders some also enjoy animal fat. Birds can be found pecking the fat off a dead deer's body, investigating road kill, looking for fat drippings in a barbecue or eating a suet cake in a feeder.
This was a very good observation. Thank you for sending in the question.
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