here are many shapes and sizes of mews. There really are few constraints except the legal ones, your own living situation, and the bird's needs. Many mews designs appear to us as very unattractive, but are actually much more sensitive to the bird's needs. While we would design a mews for ourselves that had many open windows, many birds become nervous when they cannot hide. Dark corners which, to us, look spooky, become preferred perching places.
Providing materials such as a translucent roof brings light in and barred windows which, from some angles, appear to be solid are excellent features. The flip side to the concern there is that it lets in too much heat in some climates and will overheat the bird.
There are generally two well-defined entities - a weathering yard and a mews. A weathering yard is an open area where the bird may safely spend her days during good weather. A mews is where she will live and is traditionally a stand-alone building completely enclosed. However, there are many structures that are hybrids or are only one or the other, and many situations where birds are kept in other ways.
Birds are generally kept in one of two ways - they are either tethered to a perch and dependent on the falconer moving them and providing for their needs, or they are freelofted loose in an enclosure.
If you have not yet planned your mews, try to visit several local falconers to get ideas of what works in your area or what has worked for them. They will have definite opinions on what worked for them and what didn't and how they would improve their current setup.
The overall design of the facilities to keep the bird must take both the bird and the falconer into consideration. A falconer with hundreds of acres of relatively flat land without restrictions from zoning boards may decide to build very large flight cages for each bird. A falconer in a suburban environment may have a very small mews to meet the legal requirements and keep the bird in the house or garage weathering her in the yard every day. A falconer with a Kestrel can keep her in fine condition in a 3' x 3' x 3' box with shelf perches and barring on two sides. This sort of mews can be kept on a table in the house, in the garage, or outside, even. A falconer with a Red-Tailed Hawk might want a mews that is 8' x 10' x 8' wanting to freeloft her, and will be able to keep her in perfect feather. There are a million ways to keep a bird healthy and in great condition, and more than a million ways she will find to damage a feather or injure herself. Good falconers will look for many options, try something out, and observe how it works for him ready to make changes as necessary.
The first consideration is the bird's safety. A mews must be completely enclosed not just to keep the bird in, and preferably in the most private area available. It must be enclosed to keep other animals out. Neighborhood dogs, coyotes, eagles, and other animals will all take advantage of a bird. Even cats can inflict enough damage to a large bird to mortally wound it. The first concern is the bird's safety. If you are making a weathering yard where the bird will spend the vast majority of her time unwatched, then it must be completely enclosed either with wire or a roof structure. For a small falcon like a Kestrel, a dog exercise pen is portable and allows the bird to be safe from most potential harm while being low impact on the falconer. For larger birds a larger structure will be needed.
One very common aspect to a mews is a two-door entry system. This is more typical with a free-lofted bird where there is the potential for a bird to fly out if the door is mishandled. Having a two door system reduces the likelihood of this from happening. Many falconers who use the two door system take advantage of the space between the doors to make a storage room or otherwise use the space well. If there is no way to implement a two door system, consider using a heavy canvas or duck cloth drape to act as a second door. Even a clear shower curtain will allow you to view the bird as you enter, but make sure she is not able to get past you or attack you. Some falconers have both a two door system as well as a door drape. A note to make the inner mews door open into the mews and not into the preparation area. The reason for this is, again, to help control the bird's ability to get past the falconer or attack him.
Modern falconry has many different tradeoffs that traditional falconry never had. Here a falconer has a great setup to allow his birds to weather, even though he is in a suburban neighborhood with limited land.
Birds of different ages and conditions have different needs. A bird that has injured a foot is often recommended by veterinarians to have all her equipment removed and placed into a large dog carrier in a dark room with a few inches of fresh hay lining the bottom of the carrier. This allows the bird to nest and take weight off the foot temporarily. Immature birds may need to be kept in very different structures and with different methods. Many falconers keeping an immature bird allow the bird free movement within the house while she is growing.
As with anything, a flooring is only as good as your maintenance of it. There is no perfect floor, but some substrates will fit your situation and constraints better than others. Keep it clean and regularly clean out bones, castings, food particles, and mutes. Keep it dry and well ventilated to prevent mold or insects from developing. In general, avoid concrete and brick unless they are overlaid with something else such as padded Astroturf or plywood. Consider how the flooring itself will decay, particularly when damp or with mutes sitting on it. Consider how the hawk food will sit on it, sand will stick to food, and food may sit and rot on a plywood floor depending on the techniques and environment. Consider the ability to sanitize in case of disease. Consider if it attracts or allows insects and other vermin to hide. Consider how it dries after being cleaned. Consider if larger predators can get under, either by digging or by coming through a wall. Lining the ground with a foot or so of chicken wire or hardware wire will help prevent animals from digging under a mews. Extending this out from the mews wall will also help prevent invasion.
Wood chips can make an excellent flooring material if they are used in a way where they are not breaking down. Wood chips don't overheat in direct sunlight. Wood chips also will not dull talons if a bird bates a lot. However, wood chips are a biodegradable material and, when decomposing, they will harbor mold, fungus, and bacteria. In circumstances where they are not getting wet, and are rotated out appropriately, they can be an excellent material.
Pea gravel (sometimes referred to as river bed gravel) should be 1/4" to 1/2" and smooth - not the jagged driveway gravel (crushed gravel).
Sand can be readily available and work for many falconers. It is easily cleaned out and raked and is easy to manage. However, it will reflect a considerable amount of heat on a bird. A bird who is tethered and bates will have the effect of filing her talons into razor sharp needles. Some falconers spread an inch or two of sand over just a small area of the mews to have the bird bate on that area. However, sand can get under anklets and can abrade the skin. If a bird is fed on sand the particles can be ingested and impact in the GI tract. Sand works particularly well directly underneath a falcon's perch since she mutes straight down. This allows the area to be picked clean regularly.
Dirt or Grass
Dirt or grass floorings may be the easiest flooring to care for and manage. This is a natural environment for the bird and tends to produce healthy feet, although a tethered bird who bates will dull her talons. Dirt can be raked or removed, absorbs well, and contains microbes which help break down both leftover food particles as well as mutes.
Soil types that are more clay-like will tend to dull the talons while soil types that consist mostly of sand will tend to sharpen the talons. Birds who like to walk on the ground or who pace may have the result of sharper talons, or of dulling their talons. Falconers see different results here for different birds and surfaces. Watch how things go for you in this setup and adjust accordingly.
Rubber mats can be anything from those found at home improvement stores, to horse and cattle mats, to rubber tracts laid down as a flooring. Mats are easily pressure washed clean. Black mats will heat up considerably and so the temperature must be considered as well as the amount of direct sunlight. Since the surface is impermeable, mutes will dry slowly and tend to smell more than a flooring which absorbs and dries faster.
Similar to rubber mats are Astroturf. There are many different types of materials referred to as "Astroturf" but there is only one true Astroturf. If you want to use this, go to a local driving range and ask them if they will sell old driving range mats. These are padded and have stadium Astroturf adhered to one side. These make excellent padded surfaces and protect the bird's feet in a number of ways.
Avoid the "daisy" mat of Astroturf - the type that door mats are made of. The "grass blades" are hard plastic with sharp edges and in cold weather they become brittle and break into even sharper edges. This cannot be healthy to the bottom of a raptor's feet.
Shavings may work well enough for a flooring in cold climates, but should be cautioned in warm or moist climates. Being fine, they will produce an amount of particulate matter in the air, moisture gets held in them and they can mold (although not as badly as sawdust), but perhaps more importantly, they are small enough for a bird to ingest them, especially if food is dropped onto the floor. Shavings in the system will cause an impaction and can be difficult to diagnose and put over.
Sawdust is too fine for a mews flooring. It holds moisture, molds, and can be thrown into the air and inhaled by the bird. Avoid sawdust.
Straw, different from hay, is the perfect substrate for mold spores. It likely has some mold already in it from the moisture and spores from harvest, then it has been bundled up and the mold has been allowed to grow. Being an organic material it should be avoided at all costs. Straw even near the mews should be cautioned as the propensity for developing asper is very high.
Perches inside the mews must be provided with the bird in mind. A variety of perching surfaces should also be provided. Perches and windows go together as poorly placed perches in relation to the windows will cause the bird additional stress. Some birds will want to look out, while others will want a perch where they can feel secure and hidden. In a free lofted situation with part of the mews exposed to the weather, placing a favored perch in the weather will help her be exposed to enough sun, rain, etc. Be careful of perches in mews so that they are spaced far enough from the walls that if the bird turns around, her tail will not rub. And a tip to position the bath away from perches to avoid mutes in the bath. Some falconers will even place a large rock, like a large sandstone rock or even a large chunk of salt in desert climates, on a shelf perch or on the floor as another option for the bird to perch and feak on. Placing a window perch about 18" from the window gives her a way to look out of she wants, but keeps her far enough away from the wall that she will likely not damage her feathers. More details on perches.
Mews should have windows, primarily for ventilation. As humans, we would design windows for our comfort with large expanses of open view, however the bird's needs are slightly different. First, the windows need bars to prevent the bird from getting out and other animals from getting in. Most birds want to be able to escape and to hide. Mews windows can help her achieve the feeling of hiding by having slats that appear to be solid wall from certain angles. The ventilation will help air exchange, keep the mews fresh, prevent mold from taking hold, and allow moisture and mute to dry quickly.
Consider which direction the window will face. A southwardly facing window will bring in much direct sunlight and allow the bird to bask, however if that is the direction of winds or rain, then shutters may be appropriate or a mews which faces another direction, or vents placed in particular areas around the mews to allow the proper amount of cross ventilation. some birds are ok with large windows (24"x24") others need smaller windows to prevent bating. Larger windows may make a weathering yard completely unnecessary. Some falconers put an open strip all along the bottom of the mews to allow air exchange and the bird to view the outside if she wishes, but to increase her sense that she can "get up" and hide in the corners. Some birds prefer perches in front of the window, others do not. Consider amount of light to be let in, angle of sun, and wind direction.
For mews bars, thick walled PVC pipe will hold almost any bird in and will not rot although it may be come brittle in cold weather or as it ages. However even the thick walled pipe will flex beyond what some falconers are comfortable with. Some run EMC inside the PVC pipe. This metal pipe inside the plastic pipe means that the PVC cannot be bent to a point of breaking and yet the plastic protects the bird if she does try to fly into the window. PVC is susceptible to breakdown due to UV light, heat, and is more brittle in the cold, but the thick walled exterior PVC will last a lot longer and will be more sturdy. If you will be using wood slats, anything from a 1"x2" to a 1"x6" will work. Mews bars for a Red-Tail sized bird should have no more than 1.75" of open space between the bars. Ideally there would be only 1.5" of open space between the bars. For a mews to hold any bird from a kestrel on up, it should have no more than 3/4" of open space between the bars. An additional advantage is that from an angle the bars block the visual allowing the bird not to see some things that may alarm her, and keeping her more private and unbothered by onlookers.
Also consider screening your window (placing the screen on the outside of the bars) to prevent mosquitoes and bees from entering the mews. This will reduce the likelihood of West Nile Virus and reduce the probability of a bee stinging your bird. If you plan on feeding meat in the mews, consider the early spring when wasps and yellowjackets are searching for meats and attracted to this. Either a fully enclosed mews or a change in the feeding pattern can prevent attracting a nest to be built next to your mews, and help reduce the chance that your bird is stung. Creating window insets allows a window to be fully blocked if necessary in case of storm or need for greater privacy such as breeding.
For a management setup with the bird in the house, some birds are fine without any modification to the home. Blinds or curtains will discourage a bird from trying to fly through a window, and electrical tape can be used to create "bars" on the window and discourage a bird from colliding into it.
Cleaning the mews is not necessarily a frequent occurrence, but a clean mews is important. The bathpan should be cleaned and changed regularly in order for the raptor to drink and bathe properly in it. During the summer this may be daily, during the spring or fall this may be weekly, or there may be no bathpan in the mews during the winter. Some falconers are so concerned by the regulations regarding feathers, or by a non-game bird that has gotten into the mews and been eaten, that they will vacuum the mews with a ShopVac clearing out all castings, feathers, or fur, and then even throwing away the ShopVac filter so that no feather particles clinging there can be said to "be in their possession" thereby ensuring they are completely legal with the feather regulations.
If you will be cleaning the mews, first remove all birds from anywhere near the mews. Put the bird in her hawk box or a safe weathering area for the next day or so until the air has exchanged several times, all surfaces are dry, and all cleaning products have dissipated. Use a cleaning product that is safe for raptors. Bleach mixed with water into a 10% solution is fine, or you can visit a farm supply store and find a cleaning product safe for dairy cows. A power washer makes quick work of getting mutes off of gravel, Astroturf, or walls, but be very careful that the bird is not replaced into the mews for several days as the action of power washing aerates all the dirt and mutes and disperses them into the air.
If you are in a climate that is moist and warm and Asper is a large concern you may want to periodically fog your mews with an anti-fungal treatment. This is especially useful when introducing or caring for a Gyrfalcon or Snowy Owl who are prone to Asper.
Some falconers line the inside of their mews with Chloroplast or a shower curtain or use shower stall walls, or line areas where mutes will be flung. This can be attached to the walls with pan head screws and is easy to spray or wash with a pressure washer. Walls can also be sprayed with Simple Green and then scrubbed or rinsed off. If the seams need to be sealed, a tiny bit of silicone can be used. Mews can also be cleaned with plain bleach and water per directions. Particularly difficult mutes can be scrubbed off with Oxyclean. Mews can be disinfected with Symphonel 3 which continues acting for a week after it is applied (birds should not be allowed into the enclosure until it is fully dry). One squirt of this will dilute into a fallow of water for effective disinfecting. Virkon or bleach are also a good disinfectant, however it needs to be fully rinsed before allowing a bird into the enclosure. For general cleaning simple white vinegar is useful and can be diluted 1/4 cup to a liter of water. There are bird mute enzymes that can be sprayed to help break down biological materials. Check a good farm supply store for cleaners and disinfectants for poultry farms. For any cleaning solution I am overall very cautious preferring to clean in warm, if not hot, weather. In this way I have the temperature helping to evaporate and break down the chemicals, and strong direct sunlight helping to evaporate and break down the chemicals. I like to let this works for a few days, if possible, to ensure that the chemicals will not adversely affect the bird. Be sure to read all instructions, and check if birds have any adverse reactions to the chemicals. I also will wear a simple respirator or mask as the dried particles and the chemicals can be damaging to be inhaled.
Consider the drainage and moisture level in the mews. Some falconers install PVC for drainage only to have it clog several years later. You will have a bird's mutes collecting somewhere, how will these get broken down? Do you plan on using water to hose them off? How will that water drain? A pressure washer can get many surfaces clean, but leaves everything soaked and can splash and aerize droplets that the bird, or you, will inhale. Rubber mats or driving range mats over pea gravel will leave enough space for worms, spiders, centipedes, and more, and in some climates mold, mildew, and asper can be a problem. This may be fine in your climate, or it may present problems. Indoor/outdoor carpet is usually not as easy as mats.
There are some nice features that any mews should consider.
Peephole Consider a peephole on a solid side of the mews and on the inner door so that you can view the bird and observe her without affecting her behavior. With a peephole on the door you can enter a freelofted bird's mews more safely.
Paperwork Keeping a copy of the necessary paperwork displayed in the mews can prevent many problems and help law enforcement quickly see that you are perfectly legal. Including your veterinarian's business card and the business card of your lawyer is also not a bad idea.
Thermometer A thermometer is useful when making notes in your log book, but also for monitoring the bird's environment, and the remote thermometers are a great fixture to have. Some mews have a small electric heater placed in it, or a large lightbulb to produce heat, as would be found in a chicken coop.
Food Chute Many falconers include a food chute so that another falconer can feed in case of an emergency or so that they can feed during the moult. With the new temporary care regulations an unlicensed neighbor or friend can even take care of the bird in your mews, and this may help them care for the bird without the need for any ands-on abilities.
Perches and surfaces Having a variety of perching surfaces in a variety of diameters will help keep your bird's feet in good shape.
Toys Some birds like to play. An empty two-liter bottle, dog toy, or sticks can amuse some birds for hours. Other birds haven't the slightest interest in these objects. Great Horned Owls are noted as loving to rip things up, and will tear up heads of lettuce, broccoli, or a white t-shirt for fun. If the bird is particularly into shredding, rope perches may only get destroyed in her mews. A rotten log or stump can have food hidden in it, and many Red-Tailed Hawks enjoy ripping that up to get their meal out. Some birds like to grab and hold something like a stuffed dog toy or a wool sock. Some other environmental enrichments that falconers and rehabilitators found useful include: rubber dog toys, Kong dog toys, dog rope toys, stuffed dog toys, parrot toys, tennis balls, phone books to shred, paper bags filled with leaves and tidbits, Holee Rollers (open-lattice rubber ball dog toys)and the like. Variations in the food can be stimulating. Kestrels enjoy chasing down grasshoppers. Chicken and pigeon wings can be picked at for a while as tirings. Vegetables like zucchini, pumpkins and cabbage are fun for some birds to shred.
Electricity This may seem unnecessary until you want to have a radio, a refrigerator or freezer, and lights (especially during the early dusk of winter). But one consideration for electricity is for helping the moult with special lights. Running electricity to the mews will allow you to use special lights to help your bird's moult. Some falconers put their lights on a timer so they can go out, feed the birds and leave the lights on for 30 minutes to allow them to eat, then the lights will automatically turn off.
Lights While not all mews need lights due to their design, many do have them. When lights are able to be used, consider using a full spectrum UV bulb to help the bird get the amount of UV light appropriate for her.
Video camera Many falconers now have video cameras installed in the mews and around the property to identify any predators or human disturbances. Many have been surprised to find large predators, other raptors, or enforcement agents who have visited their mews when they were not around and found a video camera to be useful in documenting all the events at a mews. It is also useful in monitoring how a bird is doing, especially in low light situations.
Whichever methods and equipment are used, they must work for the falconer, the bird, the environment, and the overall training methods. Two birds in the exact same environment may require very different methods to keep them safe and healthy. Freelofting is a great way to give the bird exercise and choice in her perching surfaces, but a highly active bird will break feathers, damage her talons, and damage her cere in even the most carefully constructed mews. Tethering a bird can work great when her personality and the environment work for it - the wrong leash or perch can cause broken feathers, dull talons, foot damage, or a broken leg. Trolley or runner systems can work great, but must not allow the bird to get enough speed to hit an endpoint too hard and dislocate a joint. Raptors are prone to damage as attested by their high mortality rate in the wild. Keeping a raptor properly in captivity requires monitoring her needs and making adjustments when warranted.
Mews, Weathering Yard, and Dog Run
Mews designed and constructed by Tim Ainge - falconer
Located in the Pacific Northwest, this mews has so many considerations that it could be located almost anywhere. It is one of the finest examples of a mews built with the bird in mind. It features cedar wood chip flooring, rope perches, and electricity as well as a preparation room.
Additional plans for this include a second mews, running water and sewage pipes for a sink, and adding a refrigerator.
Mews and Weathering Yard
Mews designed and constructed by W.J. Miller and Baine Carruthers - falconers each
Located in the South, this mews has to take into consideration large amounts of strong sunlight, heat, and rain. Insects are also an issue. With the temperature and moisture, mold and fungus is an issue which means guarding against Asper aggressively. The falconer reports he has had no problems at all with moisture in his setup with the gravel flooring base, pine bark, and deep trench for drainage.
Falconry Facility - Mews and Equipment Room
Mews of the US Air Force
Located at the US Air Force Academy, this mews is the state of the art. Each mew room features an easily cleaned floor with drainage system, adequate perches, open air windows, skylight, and food chutes in the doors. There are both individual mews and breeding chambers in the facility. Most mews do not need to be built to this degree, however with the number of people involved, the number of birds involved, the number of activities conducted, and the number of public visitors, this level of facility is required for this situation.
I'd like to thank Lt. Col Muldoon and his cadets for the opportunity to be behind the scenes with them.
Rehabilitation Facility - Mews and Equipment Room
Mews of the South Plains Wildlife Rehabilitation Center's education birds
Located in Lubbock, Texas.
I'd like to thank Rob and Carol Lee for the opportunity to be behind the scenes at their facility.
The mews features vinyl coated steel wire mesh ceiling available from aquaculture suppliers. While it is safe if a bird grabs it and sturdy enough to protect from external predators, it tends to warp in heat or too much direct sunlight.
The metal conduit bars for the windows are set with 3/4" gap between each bar (small enough to hold a kestrel). Don't bother drilling the holes under the window bar pipes as it is unnecessary.
Windows face west which gives good direct sun, but also gets overheated during summer. This will be solved with an awning made of enameled corrugated metal.
Shelf perch and other perches Tree stump perches Hardyboard is an excellent material for mew walls as it is sturdy and easy to clean, however be careful with a power washer as it can break down the board. Don't use nails, use sheetrock screws.
Use silicon calking for calking jobs (not the waterproof latex kind)
If using metal conduit for window bars, make the windows 4' high maximum - 5.5' is unnecessary and allows pipes to flex a bit too much.
Mews floors are compacted dirt with pea gravel over surrounded by concrete. This makes the mews floor a pool of water when it is cleaned. French drains or something would help solve the drainage problem.
And finally, I was surprised by Rob's advice regarding the most stunning feature of this facility. Don't do a curve! Nothing is a straight line and everything is constantly under stress - walls are curved, gutters have to curve, etc. This is more effort than necessary.
Flight Cage Aviary
Flight Chamber of the South Plains Wildlife Rehabilitation Center
Located in Lubbock, Texas.
I'd like to thank Rob and Carol Lee for the opportunity to be behind the scenes at their facility.
Mews designed and constructed by falconer Jo Turley
Jo Turley provided some commentary on the design choices for this mews.
We didn't put in a floor drain, and should have, though it can be done retroactively when/if we really need it. It is not (yet) suitable for free lofting because the inside around the eaves has ledges the hawk might want to cling upon. I don't free loft, so that isn't an issue for me. Ditto the heavy duty grill vs vertical bars - we felt the grill was better at keeping moose heads out of it. Also, it doesn't have a safety door, but that could be an easy add-on. We had to be able to move this mews on a flat bed 100+ miles, so kept the design simple and sturdy. What I like is the amount of fresh air and light and view the hawk can get, with shuttering for hawks that need darkness and temperature control. It is wired so we can have light, heat, and so we can also set up a heated drinking bowl. Since I tether and don't feed in the mews, cleaning is amazingly simple - on the astroturf mats, all around the perch, I keep an area an inch deep in spruce shavings. I scoop the dirty shavings several times a week and add fresh. The slices can't reach the walls.
We are going to put a fish eye lens in the door so as to check on the hawk before we open it - especially useful if the mews has been partially shuttered while in the early phase of training a passage bird.
My Red Tailed Hawk used it for 5 years with no problems. I kept a garden chair in it, and would have my morning tea with my hawk almost every day of the year - he would sit on my knee the while.
Open Air Aviary Mews
Mews designed and constructed by Jason Caldwell - falconer
Mews designed and constructed by Ron Kearney - falconer
This particular mews is mostly used at night. The birds are working birds and therefore are not kept in the mews during the day. They are hooded and placed here for the night.
This particular mews is inside the house, however is actually very clean.
This particular mews is outside in California where the temperature weather works well for such a small bird. In climates with very cold weather a Kestrel may be better kept inside.
Outside Trolly System
Mews designed and constructed by Derry Argue - falconer
This is a trolly system whereby the bird is leashed, but instead of being leashed to a single point, the leash connects to a long line running between two perches. The line must be clear of any obstruction and the bird must not be able to get caught or hung up on either perch. The bird then has the choice to be out in the sun or rain or to seek shelter in her hut.
The trolley system was explained to me by a French falconer, Henri Desmont, and is not my invention. I have had my male parent reared goshawk on this system for two and a half years, 24/7, and he has not broken a single feather. Obviously, falconers may need to adapt it to local conditions. The trolley system has the hawk tethered to a ring on a tensioned wire between two small huts for the bird to roost in. It seems to keep the hawk reasonably fit as my goshawk caught two January pheasants on the wing after I had stopped flying for over a month. My set up is surrounded by electrified sheep netting but in some areas it would also need to be protected from avian predators.
On my set up the wire is stretched between two angle iron stakes, each one beyond the back wall of each hut. The wire I use is a single strand of galvanized high tensile steel fencing wire, 2.5mm diameter, as used for permanent electric fencing (which I just happen to have handy!). The wire is tensioned by an ordinary fence line tensioner beyond one of the huts.
The leash is tied to a stainless steel ring, link, or small yachting pulley that runs on the wire. There is a "stop" clamped to each end of the wire preventing the ring running too far - you want to keep the leash reasonably taut so it doesn't snag on anything in the hut or on the perch. The wire could be any length in theory.
The perches I use in each hut are 2" diameter hardwood (cut out of the woods). One side is cut to leave a flat surface, then this is bolted to a steel bracket (1"X1") which is in turn bolted onto an upright at the back of the hut.
I have had the bird straddle this perch, then turn, so twisting the jesses onto the perch. I have countered that by (a) fixing windbreak material beneath the perch, and (b) fixing a wire from the end of the perch to the ground.
I cannot stress too strongly that you need to go over the whole set up to make sure nothing can snag or work loose. That is also the reason for the wind break material under the bow perch. (And, no, it isn't a little shelter for the hawk as someone suggested).
Aviary Style Mews
Mews designed and constructed by David Maritz - falconer
This is a large aviary style free flight pen measuring 24' x 12' x 8', but with 4' of space dedicated to a double door, one of the aviaries is only 20' long. The frame is from a pergola structure of 2"x4" boards with the wall of an existing structure used as one of the long sides of the aviary. The walls are large gauge field fencing (2"x4" wire) outside of white sunscreen panels. The wire mesh prevents predator entry or the bird's escape should the sunscreen rip. The birds held in these particular aviaries are Goshawks who are known for their erratic behavior. The softer walls help prevent injury should they fly about careening into a wall. The woven polyurethylene sunscreen material allows in plenty of light, yet it is always slightly dimmer inside the aviary than outside. Because of this, the birds can easily see out yet passers by cannot easily see in. In fact, many people who routinely are near this structure don't even realize that there are birds inside, yet the birds themselves have the opportunity to acclimate to people, dogs, cars, and traffic without harm.
The substrate to this structure is a flat concrete foundation covered with sand which is then covered with Astroturf. There is a 4' plywood roof over one end of the aviary providing a roost and rain shelter for the bird. Behind the roost perch is plastic for easy power wash cleaning of the mutes every few weeks. At the opposite end of the aviary is another high perch in the open and the center area has several low bow perches and a large bathpan. The entrance to the aviary is a two door chamber entry which has been effective at preventing escapes.
A dog pen has been added next to the aviary allowing the hawks to be exposed to the dogs daily and make them part of their environment.
The mews is located in the mild climate of the Northwest, but similarly styled structures are used for mews in a variety of climates including hot, dry, arid climates. Concerns in those locales would be the exposure to the weather extremes (temperature and wind primarily), and providing adequate shade and the appropriate temperature for the species in question. An aviary like this could easily be outfitted with a light spray sprinkler system to cool the area by 10° or more.
David adds that the wisteria in bloom in May makes for one of the most beautiful blossom adorned mews in the world.
Located in the Pacific Northwest, this mews does not have to consider snow, ice, or many temperature drops. For the few that occur, the bird can be brought into the house or garage for the night or a few days. The hybrid mews/weathering yard gives excellent ventilation as well as exposure to all daily routine. One argument would say that the bird may be over stressed by this, but the other is that the bird is acclimated to it. The bird has plenty of sun, but also enough rain and protection from the elements as well as the temperature.
This particular mews had just been a chain link dog run. When the falconer started renting the house, the landlord permitted a roof to be added to the dog run converting it into a hybrid mews. For a suburban falconer, this setup can be very successful.
Mews designed and constructed by Harry McElroy - falconer
This particular mews is located in hot, arid climate.
This particular mews is located in a moderate climate and a very tiny California backyard.
Mews designed and constructed by Charlie and Pam Kaiser - falconers each
This particular mews is located in a arid, desert climate featuring a full weathering yard and separate indoor mews.
Backyard Weathering Yard
Mews designed and constructed by Larry Ray - falconer
This particular mews is located in a temperate climate with cold and snowy winters and hot, humid summers.
Many falconers use their house as a mews at least some point. Some even depend on it as a part of their husbandry. For a small falcon like a Kestrel, the constant temperature may be very important. If temperatures drop to unexpected levels, having the ability to bring the bird inside insures her health. A bird may have a perch and matting for her, or just be brought in and placed in her hawk box for the night. As long as she still has enough sun and time outside to stretch and enough exercise and mental stimulation, she will be fine.
Many traditional falconry cultures are highly mobile or nomadic. While many falconers in North America have a permanent residence and permanent structure for a mews, it is perhaps the most traditional practice to be without one. Some falconers spend months traveling and hunting with their birds, others outfit their mode of transportation for only day trips. Some use their vehicles as a mobile mews - and some are outfitted well enough that they could be permanent mews whether they use it that way or not.
Various rehab aviaries http://thefeather.org/caging.htm
Incredible eagle aviary http://lonestarwildlife.org/eagle_flight.htm