How Do Birds Detect Food Vs. Object?

Birds are blessed with acute vision, and it's the primary way they find food. Colors attract them to berries, and shifts in movement indicate insects. Water birds watch for fish to jump and then swoop in. Due to their quick metabolisms and high level of activity, birds must eat nearly all of their waking hours for energy. They spend most of their time searching for food, so they become quite good at it. They may mistake a bright-colored object for food once, but after pecking it they'll realize it isn't lunch.

When birds cock their heads, they're listening for clues as to where their next meal will be. They hear other birds call and know food is nearby. Night predators, such as owls, listen for the familiar sounds of the rodents, insects and small birds they prey on. Most birds use both visual and auditory clues combined to locate their food. Objects don't make sounds, so they aren't likely to be drawn to them.

Like humans flocking to the kitchen, birds come to know where their food is likely to be found. They see the bright colors of a familiar berry bush and know the fruit has ripened. Ground-foraging birds know which stalks bear the seeds they prefer by their height and color. Caged pet birds recognize their favorite fresh food. Wild birds remember where the well-stocked bird feeders hang. They come to know what's food and what's a plaything, and aren't likely to eat it.

Flock birds hang together and watch where the other birds go when they're feasting on bushes or grasses. Birds don't flock to objects, so other birds won't be attracted to them, either. They find feeders for the first time by watching for activity. Birds high up in a tree, who see the feeder on a deck or balcony, fly back and forth and alert their families to the food source. Other birds see the commotion and join them, and soon it becomes a favorite place to find food.

Some birds, such as vultures, have well-developed senses of smell, but most birds don't. Caged pet birds do use their sense of smell and often recognize their favorite foods cooking, but outside, odors tend to dissipate in the air. With at most 100 taste buds compared with 10,000 for humans, birds don't have a great sense of taste, either, although it must be enough for them to prefer some foods over others. In experiments by ornithologist Dr. Frank Heppner to determine whether robins used vibrations to find worms, the robins found the worms even when they were not on the ground where their movement might be felt. The robins were attracted to both live and dead worms, so smell wasn't a factor either.