Rock doves or feral pigeons eat seeds and grains that they pick up from the ground. Pigeons are also opportunistic and will eat cake, popcorn and bits of bread. They have been known to eat discarded animal protein such as meat from chicken bones and cheese from pizza crusts. Doves of all kinds will also eat worms, slugs, snails, insects and small lizards. Some doves have a preference for fruit.
Doves that eat seeds have evolved a specialized digestive tract to help them process the seeds. They can be seen pecking at grit, which is stored in their gizzard. The grit is then used to grind the seeds after it leaves the bird's crop. Seed-eating doves need lots of water. Unlike other birds, pigeons don't need to raise their heads to swallow, but can pump the water into their throats like horses. Doves who live in the desert can drink the water found in cacti and other succulents and can tolerate salt water.
Baby pigeons, or squabs, are fed crop milk by both parents. This is a liquid nutrient that resembles milk. Some squabs are fed crop milk for a few days while others are fed crop milk even after they've fledged.