Birds

The presence of birds is usually welcomed, as they are indicative of a pleasant, diverse environment. However, in both rural and urban environments, when a large population of certain species is present, serious problems can occur including:

  • Fouling of buildings, causing corrosion
  • Fouling of footpaths, causing safety hazards
  • Noise pollution
  • Disease spread through droppings

Destroying birds is not effective

PigeonsMost wild birds are protected under the Wildlife and Countryside Act 1981 but certain birds are classed as pest species and can be destroyed.

The killing or taking of birds from an area is seldom an effective means of control as it creates a vacuum into which other individuals will readily move.

Destruction of the birds is a difficult control method to implement and is usually a last resort, e.g. to remove a particular problem individual from an area.

Problems with the urban bird populations are always made worse when the general public feeds birds. Discouraging or forbidding the feeding of birds would be a solution; however, it is unlikely to be a practical approach.

Usually, pest controllers have to accept the presence of birds in an environment and use a number of proofing techniques to keep them away from sensitive areas.

The main species causing bird problems are feral pigeons, gulls, starlings and sparrows. Around farm buildings, crows and rooks may also need to be controlled.

A range of solutions

Indoors

The best method of controlling bird problems inside buildings is to keep them out in the first place. Total bird-proofing can be achieved in commercial buildings by sealing all holes and openings greater than 20mm in diameter.

Doors

In many buildings such as warehouses, birds can gain easy entry via loading bays and doors. Effective proofing can be made using plastic strip curtain doors across the entrance. However, these must be allowed to hang freely and must touch the ground to prevent birds from sneaking in through small openings. Ideally, all doors should be kept closed when not in use. Self-closures are advisable.

Eaves

Corrugated panels and gaps must be filled using mortar, proprietary pre-formed sealing strips or expanding foam and wire mesh preparation. The wire mesh will give added protection, as birds may try to gain access by pecking at the softer expanding foam.

Windows

Window meshWindows are a common point of access for birds. Ideally, they should be kept closed but where ventilation is required, some form of proofing of the open window is essential.

The use of mesh or netting, placed either inside or outside the window, will deny access to birds. In many cases, it is not necessary to cover the entire window reveal, merely the opening section. In addition, louvered windows and doors will also allow bird entry and need to be proofed in a similar manner.

Outdoors

A more common problem is the fouling of buildings where birds perch or roost. A number of systems can be used to protect the buildings from this menace. They all involve either covering parts of the building with a barrier or adding material to make the area unsuitable as a bird resting site.

Netting systems

PigeonsPolythene or polyester woven netting can be used to exclude birds from areas such as light wells, ornamental building frontages, eaves, roof spaces and underneath bridges. Netting of the appropriate colour should be chosen for each application to ensure the nets are virtually invisible from the ground level.

A net which retains its plasticity when exposed to UV light and the correct mesh size must be chosen. The system is available in different sized mesh to account for the different size of the bird

Bird netting is usually attached via 2mm galvanised or stainless steel perimeter straining wire using fasteners called Hog Rings. This is supported using the appropriate fixings drilled directly into the stone/brickwork. With eye bolts in each corner, the whole assembly is tensioned using Barrel Strainers. Various intermediate fixings are also available for intricate or large jobs. Zip fasteners can be integrated into the net when access to light fittings etc is required

Care must be taken to ensure close fitment of the netting to the surrounding masonry as birds may gain access down the sides and become trapped behind the net, often causing public concern.

Anti Perching systems

It is seldom possible to protect exposed edges and gable ends of buildings from perching or roosting birds using nets. Therefore some sort of anti-perching system that prevents birds alighting on these parts of the building is required.

Pin and wire

Pin and Wire systems, principally aimed at preventing feral pigeons from perching and roosting on ledges, work by making the surface unsuitable for the birds. A spring-tensioned stainless steel wire is supported by a number of stainless steel posts drilled into or fixed on top of the masonry.

Pin and WireAs the birds attempt to land they are either repelled by the wire pressing against their breast, or if they attempt to land on the wire, they are unable to stand due to the springing and flexing motion of the wire.

The system can be used on window ledges, roof ridges, chimneys, gutters, gable ends and other architectural features

Special fixtures for application onto areas where drilling is not allowed, or unsuitable, are available. For example, supporting pins can be slotted into plastic bases, which can then be stuck onto the surface using strong adhesives.

Care must be taken as any undue pressure may cause damage to the surface material. Gutter clips can be used where pigeons are perching on gutter edges. Such clips have serrated jaws and are bolted on the gutter, usually at 1.5m intervals. Where an end fixing is required but a post is not suitable, a stainless steel split pin can be used in conjunction with an anchor rivet, drilled into the side of the structure.

It is usual to use just one run of wire along the leading edge where birds first alight. This can be sprung at one end or in several places when a longer run is used. Posts are usually placed at 0.75 to 1.5m intervals, but this interval will alter when going around intricate structures.

On wide ledges it is recommended that 2 or more runs are used to prevent birds from flying over the top of the edge wire and landing behind. A combination of different height pins (e.g. edge wire 11cm, second wire 15cm) is also advised to give a variation in the wires.

Spike systems

This comprises typically a plastic base onto which are fixed UV stabilised plastic upright spring wires. The principle is similar to the pin and wire system.

The birds are unable to gain firm footage and are repelled by the spikes. The spikes are available in several different lengths or configurations, which ensure that there is a system suitable for every need. The bases can be plugged into the masonry or attached with a silicone glue where drilling is unsuitable or undesirable.

This system is simple to use and is often more suited to smaller sections of ledge or when treating ornamental or irregularly-shaped features, as sections of the base can be easily snapped off and fixed into position