Your peafowl pen will probably ultimately depend on your monetary resources and the time you have to build it. Peafowl can thrive in many different types of pens, and every enthusiast has a different setup. Below are a few tips and guidelines to keep in mind while you are planning your new aviary.
Space - Every website you visit or breeder you talk to will probably give you a different value for how much space each pea "needs." Although there is no magic number that works for every bird and situation, a general rule of thumb is the more space the better! Most sites recommend at least 100 square feet per bird. I'd say you could easily add another hen or two without requiring 100 or 200 more square feet, but males require a lot more space than hens-think of the tail. Peacock's trains can be over five feet long, which means that turning in narrow pens isn't easy-take pity and make your pens at least ten feet wide if you can manage. This also means that peacocks can be over five feet tall while displaying, so make you pen at least six foot tall so his tail isn't damaged.
Shelter - Peafowl are hardy birds, but they need your help to make them comfortable in extreme weather. A good wind and rain/snow proof shelter is a necessity to any pen. Peafowl need a place to stay dry and warm (or cool). Whether you go for runs attached to a building or construct some sort of shelter inside the pen is up to you, but make sure it's waterproof. If winters in your area get really cold, consider insulating the shelter.
Roosts - Peafowl like to roost at night, so you should provide them with a place to do so, preferable inside the shelter (although you can include outdoor roosts as well). Roost should be a few inches wide so they don't hurt the birds' feet. I use two by fours in my pens. Roosts should be three or four feet off the ground. Peafowl will enjoy higher ones, but consider how much space they have in front of the roost in which to fly down. If the birds are forced to descend abruptly to avoid colliding with a fence the impact can be hard on their feet. Consider placing lower roosts in front of the higher ones so the peafowl can fly down in stages.
Cover - Despite their size peafowl are great flyers, so you will need to cover your pen if you want to keep your peafowl in it. Most pea pens are covered with netting. Consider something strong that will not break if a peacock flies into it (which they are liable to do if spooked) but won't hurt the bird either.
Predator Proofing - If predators get into the pen with your peafowl it can be bad news. Find out what predators are local to your area and make sure you've proofed your pen against them. Make sure the holes in the wire you use are small enough that nothing bad can get through-if you're worried, consider covering the wire with lightweight netting or chicken wire with smaller holes for an extra layer of protection. If you have a lot of aerial predators (hawks and owls) make sure your netting is strong and tear resistant. If you have a lot of dogs and foxes, consider burying your wire so they can't dig under. Predator proofing might cause extra hassle and expense, but you'll regret not doing it if you lose any of your birds to a break-in.
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