What not to feed crows

Toxic: never feed these to crows

• ChocolateToxic Theobromine and caffeine are toxic to birds.
• AvocadoToxic Contains persin, which is toxic to many birds. Skip it entirely.
• Onion and garlicToxic Can damage red blood cells in birds, raw or cooked. Watch for them hidden in leftovers.
• Caffeine and alcoholToxic Never. Both are poisonous to birds, and that includes leftovers.
• XylitolToxic A sweetener in sugar-free gum and some "sugar-free" peanut butters. Read the label.
• Moldy or spoiled foodToxic Mold toxins can kill birds, and crows cannot tell old food is dangerous. This includes moldy nuts.

Avoid: not poison, but not worth it

• Salted or seasoned anythingAvoid Chips, salted nuts, seasoned leftovers. Salt causes dehydration and kidney problems in birds. This is the most common mistake, because salted peanuts look like the right food.
• Fried and processed foodAvoid Fries, fast food, candy, pastries. Nothing good in them for a bird.
• Spicy leftoversAvoid Chili heat does not hurt birds the way it hurts people, but spicy human food is almost always salty, oily, or full of onion and garlic.
• Cooked bonesAvoid They splinter. Take meat off the bone first.
• Raw minceAvoid Australian wildlife groups warn against it for magpies: too much fat, no calcium, linked to bone disease. Cooked is safer everywhere.
• Green tomato, tomato leaves and stemsAvoid Nightshade family; the green parts contain solanine. Ripe red flesh in small amounts is fine.

The bread question

Can crows eat bread? A crust now and then will not hurt. Piles of it will. Bread fills a bird up with almost no nutrition, it molds fast, and it draws rats and pigeons to your spot, which is the fastest way to lose a neighbor's goodwill. If bread is the only thing you have, a small piece is fine. As a daily food, it is the wrong choice when a handful of unsalted peanuts costs about the same.

Foods people ask about

• GrapesSafe Yes. Sweet, hydrating and popular. Halve them for smaller birds.
• AlmondsSafe Yes, unsalted, as a treat alongside walnuts and cashews.
• Peanut butterSometimes Plain and unsalted, yes. The real danger is xylitol in some sugar-free brands. Audubon and Cornell report no hard evidence that birds choke on it; a thin smear or a mix with oats keeps it from being sticky.
• AppleSafe Yes, chopped, with the seeds removed. Apple seeds contain a small amount of a cyanide compound.
• CheeseSometimes Tiny cubes occasionally. Salty and fatty, so a treat.
• PopcornSometimes Plain air-popped only. Salt and butter are the problem, not the corn.
• Raw eggSometimes Crows eat eggs in the wild, but cooked egg is the better choice from you. Raw spoils fast in warm weather.

The full list of good foods, with how to offer each one, is in what crows eat.

Where the danger hides

Almost nobody feeds a crow a square of chocolate on purpose. The risk is in the leftovers: a pasta sauce with onion and garlic, chips, a salty sandwich, a cookie, nuts from the back of the cupboard that have gone musty. The rule that keeps crows safe is simple. If it has salt, seasoning, sauce or sugar in it, or you would not eat it yourself today, it does not go out.

If a crow ate something bad

You usually cannot do anything for a wild bird after the fact, and you should not try to catch one. Pick up what is left so no other bird gets it, and stop putting that food out. If you find a crow that looks sick, weak or unable to fly, contact a licensed wildlife rehabilitator rather than handling it. In the United States, Animal Help Now finds one near you. If you see several sick or dead birds, stop feeding and follow your local avian-flu advisories.