• Accommodation for birds maintained in captivity should be designed to allow the birds to be maintained in good health, fulfil the 'five freedoms' as defined by the UK's Farm Animal Welfare Council, and to breed (if this is desired).
• Accommodation should also enable general management procedures, including monitoring, feeding, catching, cleaning etc. to be carried out effectively and with minimum disturbance to the birds. Consideration should also be given to the aesthetic and educational nature of accommodation on public display.
• Enclosures should of a sufficient size to hold the number of animals contained within them, or to look at the situation from the other direction, the number of animals placed within an enclosure should not exceed the carrying capacity of the enclosure: overstocking should be avoided, and thought given to expected population expansion. Carrying capacity will vary depending on the number and species of birds kept.

N.B. Local climate and general conditions may vary widely and appropriate enclosure design may vary accordingly (B7).

• Waterfowl are, as the name suggests, water birds and enclosures should be designed to give access to sufficient water for bathing and swimming, not just drinking.
• Many waterfowl species are grazers and enclosures preferably should provide substantial grass areas for these birds.
• Waterfowl are frequently maintained in spacious, open enclosures containing extensive water bodies. In most cases the birds kept in such enclosures will be flight-restrained in some way.
• Whatever the size of the area in which waterfowl are maintained, every effort should be made to avoid adding "one more pair" of birds to a collection in which the number of waterfowl has already reached the capacity of the land and/or water area available, as overcrowding leads to erosion of ground, reduction in grazing area, decreased water quality and increased contamination of the enclosure with potential pathogens.

• D15 - Secretary of State's Standards of Modern Zoo Practice

• Enclosures should be designed to allow birds to carry out as many as possible of their natural behaviours (migration will necessarily be impossible). Depending on the species, large open areas for flying, ground cover for hiding, water for diving, plentiful perches or multiple objects for investigation may be of most importance. The size, shape, general layout, boundaries, construction materials, substrate, water, plants and other furnishings of an enclosure should reflect the needs of the particular species to be kept, including their social system (e.g. territorial versus colonial breeding).
• Consideration must also be given to the provision of separate pens for aggressive birds, or for very shy and timid birds. With highly territorial birds, it may be necessary to ensure than pens are placed apart from the pens of conspecifics (for example with an unrelated species in the intervening pen) or to place visual barriers between the pens, to avoid excess time being spent in aggressive behaviour between birds and to reduce the risk of birds injuring themselves on the intervening fence.
• The risk of hybridization if closely related species are maintained in the same enclosure must also be considered (see: Reproductive Management of Birds - Hybridisation).
• In all enclosures with birds on public display, at least one side should be barred from access by the public to ensure that the birds are able to rest away from people and reduce stress..
• A well-designed enclosure and its contents provides behavioural stimulation for the occupants as well as fulfilling their physical requirements.

N.B. The information below should be used in conjunction with the information on behaviour in the wild given in the section on Behaviour on the individual species pages. Where adequate information on behaviour is not available for a species, data on similar species may be useful.

(B33.1.w1, B105.15.w2, D1 - [full], V.w5).

• Waterfowl generally spend the majority of their time on water or on land, and are frequently maintained in a flightless condition, with their flight restricted temporarily by feather-clipping, or permanently e.g. by pinioning. This has the advantage of allowing the birds to be kept in very large open enclosures without concern that they will fly away.
• Although flight restriction by pinioning of downies at a few days old has been common avicultural practice for many years, consideration should be given to alternative methods of flight restriction.
• A number of species, particularly smaller perching species species, are considered particularly suitable for maintenance in traditional, fully-enclosed aviaries. Species which have been kept successfully in this way and for which this type of accommodation may be considered include Callonetta leucophrys - Ringed teal, Aix galericulata - Mandarin duck, Aix sponsa - Wood duck, sharp-winged teal (Anas flavirostris - Speckled teal), Anas castanea - Chestnut teal, Anas hottentota - Hottentot teal, and many perching species including the Whistling-ducks (Tree-ducks) Dendrocygna spp. Larger perching species such as Pteronetta hartlaubii - Hartlaub's duck, and also Tadorna radjah - Radjah shelduck have also been successfully maintained in aviaries.

Flight netting

• Is an alternative allowing birds to be maintained fully winged, which is being used increasingly for even quite sizeable enclosures. Soft, knot-less nylon mesh is preferred; this is durable and unlikely to cause trauma in the event of a bird flying into the mesh. A small mesh size reduces the risk of birds colliding with the netting becoming caught in it.
• Flight netting also excludes wild waterfowl such as mallard, which may pursue female ducks in the breeding season and are also linked to outbreaks of Duck Plague, particularly in the UK, and excludes large aerial scavengers and predators such as seagulls, crows, magpies and owls, thus reducing feeding costs and predation.
• Flight-netting is impractical for use on very large enclosures and may be brought down by heavy snowfalls and high winds. 

(B7, B37.x.w1, B105.16.w3, P4.1992.w1, N1.94.w1, V.w5)

• Waterfowl may also be kept fully-winged in open enclosures. Waterfowl to be kept in this manner may be feather-clipped in their first year, to encourage the birds to consider the enclosure as "home". N.B. not all species are equally likely to stay if kept fully winged. Aggressive species and those which tend to hybridise are not suitable for being kept free-flying (B7).
• It is recommended that only species native to the local area are maintained in this way. There are both welfare and conservation considerations against allowing non-native species to be maintained free-flying in an open enclosure. Waterfowl which leave the enclosure and fail to return may not survive; the local habitat and climate may be completely unsuitable. If they do survive, they may hybridise and/or compete with native species. It may be an offence to allow waterfowl to escape: for example in the UK under the Wildlife and Countryside Act (1981) it is an offence to release exotic (non-native) species into the wild.
• Free-flying waterfowl may also have a greater chance of transmitting disease between a captive flock and native birds, in a similar manner to wild or feral birds which may "visit" a collection

Sociability, Aggression and Breeding:

• "On moderate-sized ponds, up to one acre, it has proved advantageous to keep only one pair of each species of ducks and teal, as territory fights occur in the spring, causing the harassment and sometimes the death of females. Only when ponds and lakes are extensive enough to ensure the privacy of several breeding pairs can they be associated." (Delacour, B7)
• Many species of waterfowl may be maintained in large, same-species or mixed-species flocks. Many waterfowl species, including many geese, are sociable and would commonly be found in flocks for much of the year in the wild. However, most species tend to be territorial while breeding and some species are aggressive to other birds of their own species or other species, either all year around or particularly in the breeding season. Some species are also aggressive to people, which is of particular concern for collections open to the public.
• Aggressive species may have to be maintained in separate enclosures. Aggression, particularly in the breeding season, is usually directed to a large extent at other birds of a similar size and colouration; it is sometimes possible for a pair of small ducks to share safely an enclosure in which a pair of large, aggressive swans are being kept. N.B. Individual birds vary in temperament. Guidelines on species which "should" be kept separate can never be absolute: particular individuals of "non-aggressive" species may be aggressive, while some pairs of "aggressive" species may be less aggressive than expected.
• N.B. Authorities vary to some extent in their recommendations as to the species which should be kept apart because of their aggressive behaviour. The Aviculture section on the individual species pages, which includes information on aggressive tendencies, should be consulted before new waterfowl are acquired. The following categories are adapted from Richardson, 1999 (D1 [full]):

1. Aggressive Birds (Category 1.) (D1)- Birds that are often aggressive to their own species, particularly during the breeding season and may need to be kept in separate pens or separated when breeding: Coscoroba, Black-necked swans, Orinoco, Blue-winged, ruddy-headed geese, Ruddy, Cape, Australian, Paradise, Radjah shelduck, Eastern greylag Anser anser rubrirostris, Emperor, Greater snow goose, Canada geese - moffitti, occidentalis, minima,  Patagonian crested duck, African black duck, pink-eared duck, comb duck, Hartlaub's duck. Magpie goose. (See Appendix from D1 for the species links)
2. Aggressive Birds (Category 2.) (D1) - Birds that are often aggressive to their own species all year round and to a wide variety of other species during the breeding season. Should be kept separate as appropriate: Black, Mute, Whistling, Bewicks, Whooper swans; Egyptian, Ashy-headed, Magellan, Cereopsis geese; Branta canadensis canadensis; Falkland steamer duck, Bronze-winged duck.(See Appendix from D1 for the species links)
3. Aggressive Birds (Category 3.) (D1) - Birds that are often aggressive to all species all year round, particularly during the breeding season: Trumpeter swan, Andean goose, Magellanic steamer duck, Black spur-winged goose.(See Appendix from D1 for the species links)

• Apart from considerations of aggression, frequently breeding may be improved if pairs are kept in individual enclosures, particularly if the birds are to be given the opportunity to hatch and rear their own offspring. Separate enclosures allow greater control over feeding of both adults and their offspring, and also prevent hybridisation.

See: Incubation of Birds - Parent Incubation, Rearing of Birds - Parent Rearing, Reproductive Management of Birds - Hybridisation.

• Flight Netting

• Perimeter fences are designed not just to keep birds in but to keep predators out.

N.B. A perimeter fence, of whatever construction, will not be sufficient to contain fully-flighted birds: Flight Netting or aviary-type construction is required for fully-flighted birds if they are to be prevented from leaving an enclosure.

• When designing aviaries it is important to ensure that the strength of the roof is sufficient to prevent access by predators such as cats. 

• Waterfowl are frequently maintained in open (unroofed) enclosures, which may be very spacious.
• Enclosures should be surrounded by a predator-proof perimeter fence, designed so as to prevent predators from coming through, climbing over, or digging under the fence.
• The fence should also be constructed so as to prevent waterfowl, including the smallest newly-hatched individuals, from exiting through the fence or extending their heads out of the enclosure.
• Consideration should be given, in designing a gate, to everyday requirements but also to the possible future need to be able to bring in machinery, for example for grass cutting or silt removal. A concrete sill may be useful to avoid erosion, rut formation and puddling in this area of heavy wear and to prevent predators digging under the gate.

(B7, B29, B40)

• External Fence (Permanent Enclosure)Construction
• Flight Netting

• Waterfowl require a relatively large enclosure area to avoid erosion and poaching.The area required for a given type and number of waterfowl will vary for example with soil type: heavy clay soils with poor drainage tend to become poached and larger areas may be required if grass is to survive.
• Mixed exhibits should have sufficient space to allow birds chased by more aggressive individuals to escape.
• General guidelines for minimum enclosure size for a pair of waterfowl are: swans: 400m2, large geese: 300m2; small geese: 200m2; large ducks 100m2, small ducks 50m2. Most waterfowl require approximately 50% of this area to be water. A larger proportion (up to 80%) may be land for geese. Even the most aquatic species require some land as a loafing area (D1 [full]).
• For a mixed-species group it is more difficult to give precise recommendations due to the wide variation in the size and requirements for land and water of the species involved. One suggested guide is: "Ten pairs of the smaller geese and forty pairs of ducks to an acre of water are a good proportion for enclosures." (Delacour, B7).

(B13.46.w1, B30).

Internal barriers for waterfowl:

• Need only to be about three feet or one metre high. As with external fences, fences should be designed to prevent waterfowl, including the smallest newly-hatched individuals, from exiting through the fence or extending their heads out of the enclosure. Constructing or overlaying the bottom 8-12 inches (20-30cm) of fencing with either a solid material (e.g. boards) or small-gauge wire netting (e.g. 1 inch by 1/2 inch weldmesh, or 1/2 inch chicken wire will "proof" the pen against exit by even the smallest ducklings.
• Planting bushes along fences both disguises the fences (for public display) and provides shelter for the birds. Additionally, such bushes provide a visual barrier between birds on either side of the dividing fence; such a barrier may be necessary to control aggressive interactions.
• Where internal fences also act to separate the birds from members of the public, bushes may also be used on the outside (visitor-side) of external fences as stand-off barriers.
• N.B. As with external fences, regular inspection is required to ensure fences are in good repair.

(B7, B29, B30, B40, V.w5)

• --

• Waterfowl require more water than most other bird groups and high water quality is particularly important. A constant flow of water is ideal. Water may be taken from a stream running through the area, diverted from a stream or river, taken from an underground source (e.g. by sinking a well) or mains water may be used. Pipes or a narrow connecting channel may be used to transport water from the source to ponds in different enclosures. Generally, mains water will be suitable as a supply only for relatively small ponds.
• Water pressure should be sufficient to facilitate rapid cleaning and refilling of ponds.
• In all systems, high water turnover rates assist in keeping water clear and reducing build up of waste products and disease agents such as bacteria and parasites. It may be possible to keep a greater number of waterfowl on a given area of running water than on a similar area of stagnant ponds.
• Where continuously-running water cannot be provided, ponds should be emptied and cleaned regularly. Small ponds need to be cleaned more frequently than large ponds, and in general cleaning is required more often in summer than in winter; e.g. weekly cleaning in winter and twice weekly in summer may be required. A practical alternative to complete drainage and refilling for large ponds is to partially drain and refill. This may be more effective for water exchange than continual water input with overflow drainage. Removal of half the water followed by rapid refilling is also effective in reducing algal blooms (B23.37.w1).
• Permission is required from the riparian owner before water may be abstracted from a stream or river. In the UK this will usually be the Environment Agency. A licence for water abstraction may depend on reaching stringent conditions of cleanliness prior to returning the water to the source. Water may be cleaned by using reedbeds (Phragmites australis)(see: Reedbeds for Water Cleaning) or sedimentation pools.
• If a stream runs through the pens, it is important to know minimum and maximum water heights for siting of nests and nest boxes.
• If water is used to fill a series of ponds, parallel or serial filling and drainage may be used.

1. Parallel filling involves water running separately into each pond from the water source and leaving each pond directly into a drainage system. This system tends to use more water, but is preferred due to the reduced risk of transmission of water-borne diseases between pens.
2. Serial filling involves water running into one pond and then, generally by gravity, using connecting streams or pipes, from one to another of a series of ponds, before leaving the final pond for the drainage system. This system may require less total water output, which is advantageous particularly where water is scarce. However, the system produces a considerable potential for transmission of  water-borne diseases between pens.

• Pipes connecting ponds to one another or to source/drainage systems should be constructed in such a way as to ensure that waterfowl cannot become caught in them, or pass through them. Outlets should be inspected daily to clear debris which may block them.
• Where water is scarce, a recycling system may be used. This is frequently used in combination with serial filling, but could also be used with parallel filling. Incorporation of a filtration system (e.g. sand filtration) is advisable to reduce both silting and transmission of potential pathogens, and the water may also be aerated.

Filtration Mechanisms:

• Mechanical, chemical or biological filtration systems may be used.

Aeration:

• Bubblers are effective at oxygenating water and also provide some degree of turbulence and therefore water mixing. Compressed air is pumped to a diffuser on the bottom of the lake or pond, from which air bubbles rise to the surface. Fountain-type spray systems may produce some degree of aeration although this is likely to be significant only on small ponds. Mechanical aerators paddlewheel aerators create turbulence and thereby both aerate the water and promote water circulation.

Drainage:

• Small ponds may be constructed on a mound,or on naturally sloping ground allowing drainage by a simple siphon.
• Alternatively, a permanent drain pipe with plug may be built into the bottom of the pond at the time of construction. 
• Drains should be of sufficient diameter to allow a reasonable speed of drainage and to reduce the risk of blockage.
• Used water may be led away to a soakaway (see: Soakaway for Water Drainage), ditch or main drain.

(B7, B10.26.w1, B11.33.w1, B23.37.w1, B29, B37.x.w1, B94, B95, B97, B105.16.w3, D1)

• Reedbeds for Water Cleaning
• Soakaway for Water Drainage

• Waterbodies and/or watercourses provided for birds should be designed with consideration for the needs of the bird species to be maintained. Depending on the species, water may be required for drinking, bathing, swimming, feeding and mating.
• For many species only shallow water should be provided, even for bathing. This will reduce the chance of birds drowning if, for example, they are startled during the night and are crashing about the aviary.
• Some birds such as waterfowl, flamingoes and penguins require much more water.

• The area and depth of water required will vary considerably with the species of waterfowl kept as well as with the number of birds. For most species, except in very large enclosures, it is suggested that approximately 50% of the total area of the enclosure should be water, for enclosures of size: - swans, 400m2; large geese, 300m2; small geese, 200m2; large ducks, 100m2, small ducks, 50m2. With geese, this may be reduced to only 20% of the area, although more should be provided if enclosure size permits.
• For dabbling ducks, large areas of shallow water are preferred, while diving ducks require at least 50% of their water area at least 60cm (two feet) deep and preferable 90-120cm (three to four feet) deep, with a maximum depth of two metres or more; neck-deep is preferred for swans.
• Ponds intended to house mixed species should vary in depth to fulfil the requirements of different waterfowl species. Ideally, still and running water and large and small water areas should be provided within an enclosure to suit their varied preferences.

N.B. Overcrowding should be avoided, as this leads to fouling and build up of potentially-pathogenic micro-organisms.

(B29, B37.x.w1, B97, D1).

Banks:

• Need to be sufficiently shallow (30 degrees preferably, and no more than 45 degrees) to allow birds to exit the water easily, with particular regard to the requirements of species which are clumsy on land, downies, and individuals being chased. Ramps may be used on areas of steep bank to avoid birds becoming trapped on the water, but these are not suitable for diving ducks. Ducklings which cannot exit the water and become wet may quickly drown (see: Drowning)
• Banks are also subject to considerable wear. Banks of streams and lakes are subject to wear from water movement (flow, waves). Banks of all waterbodies and waterways used for waterfowl also are liable to damage from the waterfowl themselves probing and dabbling. In general, some form of protection will be required to reduce erosion, extending out from the water for a full neck's-length of the waterfowl species kept. Erosion at the junction between a surround and the soil may produce a muddy area in which bacteria such as Mycobacterium avium (Mycobacterium avium-intracellulare complex) may build up.
• Concrete may be used to reduce bank erosion; this requires an initial outlay in time and materials, and tends to be rather obtrusive but is relatively long-lasting. Concrete may be made less obtrusive by matching the colour to the soil. It is important to ensure that the concrete is smooth to reduce the risk of chronic trauma which may lead to bumblefoot. 
• Stone flagging, crazy-paving or natural rocks placed along the banks provide a more aesthetically-pleasing alternative to reduce wear on banks, and also form a loafing area on which waterfowl may sunbathe.
• Netting laid on the ground may also be used to reduce erosion. This should be securely pegged down and extend well below (1 ft or 30cm) the water level. Grass or other vegetation growing through it will soon hide the wire. Netting used in this way is less durable than concrete or flagging, but may be cheaper and take less time to put down.
• A wider surrounding area of gravel, cement, paving stones, bricks or shingle may be used to reduce the amount of soil carried into the water on the feet of the birds.

(B7, B10.26.w1, B11.33.w1, B29, B30, B37.x.w1, B41, B94, B97, B105.16.w3, D1, V.w5)

Pond linings may be used for waterfowl:

• Natural: Natural, mature lakes or ponds with sufficient depth, water input and natural aquatic flora and fauna are usually of great benefit. Shallow natural water bodies with low natural water input, or which have been neglected, may require considerable work in restoration and maintenance.
• Premoulded plastic ponds are expensive for their size and are rather small. They should be considered suitable only for e.g. one or at most two pairs of small ducks (e.g. mandarins (Aix galericulata - Mandarin duck) or wood ducks (Aix sponsa - Wood duck )), or for domestic waterfowl. They are simple to construct, requiring only the excavation of a suitable hole to allow the pond to be sunk to ground level. Such ponds quickly become fouled and required emptying, cleaning and refilling frequently - perhaps even daily, particularly in warm weather.
• Concrete ponds: have been used for many years and may be constructed in a variety of shapes (see: Pond Construction (Concrete)). More recently there has been increasing use of various synthetic liners (see: Pond Construction (Synthetic Liner)).
• Clay: clay soils may allow the construction of ponds without any lining other than the clay. The clay must however be well compacted (puddled) if it is to hold water reliably. Clays with fine particle size have better water-impermeability. Clay may also be applied to a dug out area of other soils in a layer at least 30cm (12inches) thick, and compacted well. Specialist equipment such as rollers or a hydraulic excavator may be required for puddling clay for large areas. Leaks may develop if the clay is allowed to dry out (e.g. if water levels fluctuate) or if deep-rooted plants grow through it (B93 - [full - see Chapter 7].

Islands or floating islets:

• Should be constructed in ponds where possible. Most waterfowl species feel secure on islands and prefer to rest and/or nest on islands. These also provide a degree of protection from predators. Simple rafts may be constructed from inch-thick (2.5cm thick) planks fastened together with battens. Plastic containers, partially filled with water and fixed to the underside may be used to provide buoyancy and the raft may be anchored to a weight or to the bank (B108).

N.B. General Maintenance is required:

• A portion of each pond should be shaded (either naturally or by artificial means).
• Large-leafed underwater vegetation assists in maintaining oxygenation and water-life but are unlikely to be maintained in a small pond.
• Sturdy marginal species may be established at the edges of even small ponds. These improve the aesthetic appearance and provide cover. (See: Marginal / Emergent Planting of Waterbodies).
• Shallow water bodies, including natural water bodies, may require periodic dredging to remove sediment.
• Leaves falling into ponds from overhanging trees should be removed to reduce sedimentation and blockage of drains.
• In freezing weather in winter, birds may be able to keep an area of water open themselves. If water does freeze totally, on small ponds it may be possible to break the ice and remove it. Alternatively, water should be provided in bowls, refilled several times daily (B11.33.w1, B41, V.w5).

(B7, B13.46.w1, B23.37.w1, B29, B40, B41, B93 [full] B95, B97, B105.16.w3, B108)

• Marginal / Emergent Planting of Waterbodies
• Pond Construction (Concrete)
• Pond Construction (Synthetic Liner)

Concrete

• Being hardwearing, is commonly used as a substrate in areas which are subject to considerable wear, for example at gateways and around food troughs and the banks of ponds. However, the use of concrete should be minimized as it may lead to the development of callus, foot abrasions and Bumblefoot particularly if it has a rough, abrasive finish.

Grass

• Is important for geese, swans and some duck species (e.g. wigeon) for grazing. It is difficult to provide sufficient grazing for winter, when supplementation may be required. Stocking density should be sufficiently low to allow grass to become re-established each spring (see: Food and Feeding for Birds).
• Well-managed grazing areas may provide much of the total nutritional requirements of grazing species, while overgrazing may lead to poaching of the ground, the encroachment of coarse, unpalatable grasses and other plant species such as nettles and thistles or loss of ground vegetation. On the other hand, grasses which are undergrazed and allowed to become too long increase the risk of the development of gastro-intestinal impactions (see: Impaction).
• The ideal sward length varies depending on the bill length of the waterfowl grazing it: shorter grass is better for species with shorter bills, longer grass for those with longer bills.
• As well as providing food, grass should act as a protective covering for the soil, reducing erosion, particularly in wet periods and under the puddling attention of waterfowl feet and bills. As with other vegetation, it is advisable to allow grass to become established before waterfowl are introduced to an area.
• Annual or biennial (every second year) cultivation, resting and reseeding has been recommended to minimize contamination by pathogens by increasing desiccation and exposure to sunlight. Re-sowing and resting for at least 12 months is required before an area may be considered "clean" of parasites such as Cyathostoma (See Gapeworm Infection).
• Unpalatable grasses have sometimes been used to provide a ground covering for aesthetic purposes. If such grasses are used it then an alternative supply of green food must be provided for grazing species.

Temporary substrate:

• In cold winter weather, depending on the climate, the ground may become covered with snow and ice. In such conditions, straw may be provided as a temporary substrate to give an alternative surface for the waterfowl to stand and sit on. This provides some protection against Frostbite.

(J23.16.w3, B10.26.w1, B11.33.w1, B29, B30, B37.x.w1, B40, B95, B105.16.w3, B139D1)

• Food and Feeding for Birds

• Protection from cold: furnishings may also be required to provide protection from extremes of temperature and precipitation. Heated night enclosures/sheds, bedding material over snow, windbreaks and water kept unfrozen by artificial means may improve the ability of some species to withstand cold.
• Protection from heat and sunlight: for species in which sensitivity to high ambient temperatures is problematic, advantage should be taken of natural microclimates, such as the existence of shade trees. Valleys may provide reduced exposure to sunlight and exposed locations tend to have cooling breezes. Shade netting should be provided where natural plantings do not provide sufficient protection from the sun.

(B96, B105.16.w3, V.w5).

• Plants for waterfowl enclosures should be chosen with the needs of the birds in mind. Additional considerations are aesthetics and ease of management. Native plants should be used if possible, and non-native plants which are known to be invasive should be avoided.
• Trees may be used to camouflage fences and to provide shelter. Conifers are very useful for these purposes. Live hedges may play a dual role of hiding low fences (internal fences) and also provide shelter and seclusion for the birds. Trees and bushes may additionally provide roosting sites, shade, nesting sites, nesting material and habitat variety, as well as visual barriers which may assist in reducing aggressive interactions between birds.
• For maximum aesthetic appeal, and to increase habitat variation, trees and shrubs may be planted in groups, with plenty of space in between. Suitable shrubs should be provided at the edges of the pond for species which prefer cover for sleeping; low, overhanging shrubs provide some protection from aerial predators.
• Where natural plantings are inadequate to provide protection against wind and draughts, artificial wind-breaks may be provided, for example by the use of screens of wattle or osier hurdles, round the enclosure sides or on pool banks. Shade should be provided over part of the water area, by means of shade netting if necessary.
• In general, waterfowl tend not to not use man-made shelters such as sheds. However an open-fronted shelter may be useful for feeding birds in bad weather, or in snow, and shelters with supplemental heating may be required for tropical species in winter.
• Perches should be available for the Perching Ducks and the Whistling-ducks (Tree-ducks). Partially submerged logs and tree stumps will be used by a wide variety of species.

N.B. SPECIFIC CONSIDERATIONS:

• The amount and type of shelter required will vary depending on the local climate and on the waterfowl being kept. In some climates heated housing may be required for less winter-hardy species for the whole winter.
• Dense cover, while being beneficial in terms of shelter for the waterfowl, may also produce damp shaded areas allowing survival and build-up of bacteria such as Mycobacterium avium (B37.x.w1).
• Densely growing tall grasses, reeds, bamboo etc., while excellent in providing cover and nesting sites for waterfowl, may also provide shelter for pests such as rats.
• The edges of ponds and lakes should be planted with emergent and marginal plant species as well as larger shrubs to provide cover and nesting sites. (See: Marginal / Emergent Planting of Waterbodies.
• Consideration should be given in the siting of deciduous trees to the problem of leaves covering ponds and clogging their outlets.

DOMESTIC WATERFOWL:

• Domestic waterfowl are commonly kept in enclosures which are not predator proof, and housed at night. Houses should be predator-proof and of a size sufficient for the number of birds to be kept (3 square feet per duck - B16.19.w1). The floor should be covered with bedding, such as wood shavings, and these must be cleaned out and renewed regularly.
• Domestic waterfowl quickly learn to be driven into their house at night by a single person. Patience, perseverance and possibly an extra person may be required initially. The house should be sited along a fence and preferably in a corner, so that birds can be guided along the fence line into the house.

(B7, B29, B30, B37.x.w1, B40, B95, B96, B97, B105.16.w3, P4.1992.w1, V.w5)

• Marginal / Emergent Planting of Waterbodies

Nest Placement:

• Many species of ducks and swans prefer to nest surrounded by water. On sufficiently large ponds, an island may be constructed built up from the pond bottom, or a floating island (raft) constructed, covered in turf and secured out in the water. On large islands, several well-spaced nest boxes may be provided, well concealed and placed well apart from one another.
• Most species of waterfowl nest in cover of vegetation, for example in grass, weeds, reed beds, between rocks or tree roots, under bushes. Reeds and rushes should be planted around pond edges, clumps of sedges in more open areas and pampas grass and sand sedge may be used in dry soils.
• Many ducks will nest only a short distance apart from one another if there is ample concealment available.
• Natural cover may be supplemented by the use of clumps of branches, such as evergreens or broom stuck into the ground.

Nesting Material:

• Suitable nesting materials such as grass, small branches, leaves etc. should be provided for species which build substantial nests (e.g. swans, some geese, whistling ducks). In general, nesting material will simply be pulled into the nest if it is in reach, not specifically carried to the site.
• Nest sites such as boxes off the ground should have suitable nesting material provided inside, as the birds will not take nesting material (other than their own down) into the box.
• Nests consisting of piles of vegetation may be provided partially build in suitable locations for swans, with a base of sticks topped with softer materials. If water depth may vary these nests should be sited above expected high water levels. Loose nest-building material should also be provided around the nest base for the swans to complete the nest for themselves.

Nest Structure:

• Open-fronted nest boxes, without a floor (i.e. eggs rest on the earth) are often acceptable. These should be rectangular, and of a size allowing the intended user to turn around. Sizes may vary from 18 inches by nine inches (45 by 22.5cm) to 3ft by 1.5ft (60 by 45cm). Similar boxes with a hole just large enough for the intended user to gain entrance should also be offered. Boxes fixed on a pole just over the water are also used, and bottle-shaped woven baskets placed along banks. Hollow logs, old metal drums and old chimney pots may be used as nest boxes. All of these may be hidden in clumps of tall grass or under thick shrubs, or screened with cut branches if natural cover is not available. "Wigwams" may be constructed from straight branches or bamboo, with the bottom ends stuck into the ground and the tops tied together with string. Lawson Cypress plants may have the tops cut off and be trained to trail at low level, providing cover for nest boxes and even, once they reach the ground, nest sites beneath the plant itself. Old tyres with earth and dried grass inside may be used by geese; these provide cover but also allow the goose to observe its surroundings. Soil several inches thick should be provided in every structure which is not directly on the ground.
• Artificial burrows for shelducks may be created by using a length of drainpipe for the entrance tunnel with a buried box forming a small nesting chamber at the end. The nesting chamber should have a removable lid of e.g. wood or slate to allow access to the nest for inspection or egg removal. 
• Species which normally nest in tree holes above ground level require nest boxes or barrels raised several feet above the ground, e.g. on a post, or in a major fork of a tree if suitable low-growing trees are present in the enclosure. For flight-restricted birds, these require an access ramp or sturdy branch leading from the ground or water to just underneath the entrance hole. Suggested entrance hole sizes vary, e.g. about five inches diameter (Aix sponsa - Wood duck), or four inches (Aix galericulata - Mandarin duck) (B41) versus three and a half inches diameter suggested for mandarin-sized birds (B29). A sloping roof is suggested and the roof should overhang the entrance hole, shading it. Weldmesh or coarse hessian sacking attached to the inside under the entrance hole will provide footholds for exiting ducks. A hollow log may also be used for tree-nesting ducks, again with a ramp leading up to the entry hole at the top, and a wooden lid. Tall logs (e.g. four feet high), placed standing vertically, may be subdivided with a false "floor" half way down to form two chambers, and e.g. earth placed in the top chamber.
• Elevated nest boxes, placed over water or land, are appreciated by most Dendrocygna spp., although pinioned birds will use ground-level boxes. A suggested size for these species is 30.5cm square, with a height of 56cm at the front sloping backwards to 51cm, an entrance hole of 13cm and a perch on front for pinioned birds. Such boxes may be constructed of plywood or pine, 1.3cm thick, and holes may be drilled into the bottom for drainage. A "climbing" ladder such as a strip of wire mesh attached to the wall leading up to the exit hole should be provided to assist ducklings in exiting (J23.13.w10).
• Stifftails prefer a dark, protective rushy environment for nesting. Land-based nest boxes surrounded by vegetation on the shore may be used. An ideal site may be produced by constructing a floating or fixed raft. A fixed structure should be placed sufficiently far from the bank to allow waterfowl to swim behind it and to provide protection from predators and is constructed on top of four poles driven into the pond bed, with a wooden frame, about 5ft square, attached at a couple of inches (a few centimetres) above water level and floored in weldmesh or stiff wire netting, with a very shallow ramp leading into the water to allow for a decrease in water level. Floating rafts must be constructed with regard to buoyancy and should be tethered to the bank for (human) access. In either case the edges should be lined with rushes or junctus reed, with their roots reaching the water. Rushes should be used to construct a nest in the centre, with the whole structure hidden by pushing willow branches or bamboo into the pond bed on the sides, bending them over the raft and tying them together. N.B. easy access is important, remembering that stifftails are clumsy on land (B29).

(J23.13.w10, B7, B29, B41, B95, B97, P4.1992.w1).

• Perches should be provided for most species of birds. The size of the perches should be appropriate for the species of birds being hospitalized, with more than one perch provided if possible, and with variable diameter and surface texture. Additionally, most birds prefer to be located high up, where they can look down on intruders.
• Tail guards may be used to avoid damage to the tail feathers. This is particularly important for species such as raptors in which flying and precise control of flight are vital.
• If possible, provision should be made for hospitalized social species to have contact with other individuals of their own species. Visual and/or auditory contact should be provided if physical contact is not possible or is contraindicated by other factors.
• Hygiene requirements: The possibility of patient to patient spread of infection and the risk of zoonoses must be remembered and minimized. Good ventilation is essential. Rooms should be easily cleaned and dust-traps avoided. Cages should be constructed from impermeable materials (e.g. metal, plastic, fiberglass, sealed concrete) which can be easily cleaned and disinfected. Wire mesh cage doors should be avoided due to the risks of feather damage; doors constructed with vertical bars are safer. Perches should be placed away from food and water containers, to avoid contamination of food and water with droppings.
• Substrate: Cage floors may be covered with disposable paper and/or constructed with a removable tray-type floor. For larger birds, consideration of appropriate substrate is very important. Floors should be non-slip, particularly for long-legged birds, non-abrasive and easily cleaned. A cage floor made of plastic-covered small-mesh netting may be used for water birds. The use of straw and hay should be avoided, due to the risk of Aspergillus spores.
• Heat: Hospitalized birds frequently require additional heat and a heated hospital cage is very useful for small birds. Rooms used for larger birds should also be capable of being heated. Heat lamps, which mat be raised further from perches to lower the temperature, or fitted to a dimmer switch to control their output are useful in allowing birds some freedom to chose their preferred temperature, but must be used with caution if the bird is immobile and unable to move away from the heat. An ambient temperature of at least 26°C may be useful to decrease the energy requirements of ill or injured birds, and an even higher temperature such as 38°C may be useful initially (24-48 hours). Placing a bird inside a box or cage next to a hot radiator may be useful temporarily, or placing a hot water bottle, well wrapped in a towel, in the bottom of the box.
• Ventilation: Good ventilation is important, but without draughts.
• Lighting: A reduced lighting level is frequently useful for hospitalized birds. Hospital accommodation (rooms and/or cages, as appropriate) should be designed to provide a dark environment (e.g. for birds recovering from anaesthetic, or which have been stunned) and also subdued lighting but with sufficient light to allow feeding. If a cover such as a towel over the door is used to provide darkness it is important to ensure that the cage occupant is still observed regularly.
• Water containers: water bowls should usually be provided above floor level and be sufficiently small to discourage the bird from trying to bathe in the bowl. A shallow bowl may be provided for bathing if required. Provision of deeper water may be important for some aquatic species. When swimming water is provided it must be kept clean, preferably by using a constant flow with surface skimming, or if this is not possible then the water should be changed frequently - e.g. two to three times daily.
• Privacy: Wild birds, unless habituated to humans, are liable to be highly stressed by close proximity and sight/sound contact with humans and domestic species such as cats and dogs, while all "prey" species are likely to be stressed if in sight of predators. Such stressors should be reduced as much as possible. This is particularly important to consider when birds are being maintained in a hospital which is also used for other species. Provision of a sheltered area such as a box in or behind which the bird may hide may be advantageous, although a balance is required concerning the need for monitoring.
• Enclosures used for longer-term accommodation of birds during convalescence and rehabilitation should have at least one side which is "out of bounds" to humans. It the area is visited by the public (as may be the case with some wildlife hospitals) it is particularly important to ensure that fencing and/or plantings enforce this restriction. [D1].
• Monitoring: Wild birds will frequently attempt to hide their illness from an observer, making monitoring of their true condition difficult. Consideration should be given in designing hospital accommodation to enable the occupants to be observed without their being aware of the observer. This may involve one-way glass panels, a wide-angle lens viewer in the door or the use of close-circuit television.
• Temporary accommodation, such as may be used in treatment of birds in the field (e.g. at the site of a botulism outbreak (Avian Botulism)) , should be constructed of materials sufficiently durable for the intended period of use. Consideration should be given to the requirements of the occupants for food, water, shelter from the elements (wind, precipitation, excess sunlight), perching etc. Netting which may not easily be visible to birds should be marked (e.g. with pieces of tape) or covered with opaque material to avoid collisions due to birds trying to fly through it.

(B11.4.w17, B11.14. B14, B36.6.w6, B105.16.w3, B117.w15).

GENERAL - SUBSTRATES AND FURNISHINGS

• Accommodation should be designed to allow maintenance at a higher ambient temperature if required, for example 35-40°C for oiled birds before washing.
• Social species should be housed in groups if possible, and within sight/sound of their conspecifics if this is not possible.
• Maintenance on concrete for any length of time may lead to damage to the foot surface and the development of Bumblefoot. Butyl rubber matting or artificial turf are more suitable substrates. Net-bottomed cages may be used short-term for species which normally spend the majority of their time on water, for example prior to washing oiled birds (P14.5.w5).
• Perches should be available for perching ducks and whistling-ducks (tree-ducks); flight-restricted individuals of these species will appreciate a low perch which they can step or hop onto.
• Temporary pens, which may be used e.g. for waterfowl being treated for botulism, should be moveable (to prevent excessive contamination of substrate with droppings etc.) and/or built on an easily-cleaned and disinfected surface. Appropriate water and shade provision should be incorporated.

PROVISION OF WATER

• For waterfowl species which normally spend the majority of their time on water, it may be necessary to provide specialized accommodation which enables the birds to remain on water. This is particularly important for seaducks and stifftails. Foot and leg joint problems are common if such species are maintained in solid-floored accommodation and Keel Lesions may also develop. Net-bottomed cages may be used short-term, for example prior to washing oiled birds (P14.5.w5).
• Water for bathing is essential unless absolutely contra-indicated by the treatment or state of health of the birds (e.g. waterfowl being treated for botulism and unable to hold their heads up reliably should not be given water they can drown in). Maintaining waterfowl without access to water may result in plumage problems including loss of waterproofing, foot problems and cloacal problems (see: Cloacitis (Vent Gleet)).
• Provision of water for swimming is also particularly important in waterfowl recovering from leg injuries (B11.33.w1).

(B11.33.w1, B11.4.w17, B13.46.w1, B36.2.w2, V.w5)

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