What do I need to know about raccoons if I keep chickens?
*Small, omnivorous mammal with grey fur and black "bandit" mask over the eyes. It also has a distinctive, bushy, black-striped tail.
*Up to 30 inches long, and weighing up to 20 pounds
Found almost everywhere in North America, as well as in some introduced areas in Europe and Asia
A raccoon that gets into your coop or run will normally kill multiple birds if they can get to them, and the bodies will usually be left where they were killed, rather than carried away. Raccoons won't eat the whole bird or even most of it: they will often just eat the contents of your birds' crops and occasionally some of the chest. They are awfully destructive of your flocks' lives without bothering to eat much of their victims.
They can climb walls and over fencing; they can reach their hands through wire mesh that is too small for their whole bodies to fit. In that last case, they will pull out parts of your birds if that is all they can get reach. They have great manual dexterity and can open complex latches and closures. They can dig under fences and into runs. For most people in the US, raccoons are probably the worst and most common wild predator of chickens.
Protecting Your Flock
First, don't attract raccoons to your yard. For instance, don't leave out cat food, and make sure they can't get to wild bird feeders or any seed beneath the feeders. In dry areas or during dry periods, raccoons may be attracted to sources of water in your yard, too. Don't leave anything out for them!
To keep your flock safe, make sure any wire mesh on your coop is securely attached, because raccoons will try to pry it off or bend it enough that they can squeeze through. Don't use chicken wire: chicken wire is not a barrier to predators. Raccoons and other predators can tear right through it like tissue paper. (Chicken wire should only be used to keep chickens in, not to keep predators out.) Ideally, use hardware cloth with a fine mesh that raccoons can't reach through (use 1/2" or 1/4").
Raccoons are very smart, but although they have been shown to open complex latches in laboratory tests, they will not usually be driven to figure out something really complex in the real world unless they are starving and all their easy meal options are gone. On your coop, latches that require two or more steps to operate are best. For example, a simple gate latch can be usually secured from raccoons just by inserting a screw lock carabiner into the bottom hole.
On the other hand, some people simply padlock everything. That is not usually necessary, and can make access more inconvenient for you, too. However, with a padlock, you will know they are safe.
Raccoons are chiefly nocturnal, so if you free range your flock during the day, be sure to lock your birds up securely at night with the precautions recommended above. Raccoons are carriers of rabies, so if you do see a raccoon out during the day, be very cautious. It might just be hungry, but it might also be sick. Your birds can't get ill with rabies, as avian metabolism is just too different... but you can! Use extreme caution.