What effect does rock salt have on birds when they eat it?

Rock salt can be harmful to birds when ingested, as it can lead to salt poisoning. This condition occurs because birds have a limited ability to excrete excess salt, leading to dehydration, kidney damage, and, in severe cases, death. Symptoms of salt poisoning in birds may include excessive thirst, lethargy, and neurological issues. It's important to keep rock salt and other salt sources away from birds to ensure their health and safety.