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Songbirds
Swallows
![[Swallow]](../img/cliff5_200.jpg) Photo by Walt Carnahan Management of Swallows Actions to solve problems with swallows should be started as soon as they are identified. Cliff swallows are colonial and the number of nesting birds can increase significantly from year to year. They are best managed by nest removal and exclusion techniques. There are no chemical toxicants registered for cliff swallow control, and shooting, trapping, or harming swallows is not permitted. |
Legal Status and Permit Requirements
All swallows are included under the Migratory Bird Treaty Act of 1918 as migratory insectivorous birds and as such are protected by state and federal regulations. It is illegal for any person to take, possess, transport, sell, or purchase them or their parts, such as feathers, nests, or eggs, without a permit. As a result, certain activities affecting swallows are subject to legal restrictions.
The California Department of Fish and Game, the enforcement agency, considers February 15 to September 1 to be the swallow nesting season. Completed nests during this breeding season cannot be touched without a permit from the U.S. Fish and Wildlife Service. Outside of these dates, the nests can be removed without a permit. During nesting, a permit authorizing nest removal will be issued only if it can be justified by strong, compelling reasons. For example, such justification might include a health or safety hazard posed by a nesting colony situated over a doorway/entrance, near a loading area of a warehouse or a food processing facility, or at an airport if aircraft and maintenance safety are impaired.
If eggs or young are in the nest when a permit is requested, the application will probably be denied. It is best to request the permit during the nonbreeding season and well before spring nest construction begins. Past history and problems will be taken into consideration. The permit is issued for one season only. The permit will authorize the permittee or the permittee's employee(s) to use specified methods to remove the nests. The number of nests removed must be reported within 10 days after the permit expires.
For all permit requirements, contact the main office of USDA-APHIS Wildlife Services in your state. In California the address is 3419A Arden Way, Sacramento, CA 95825; phone (916) 979-2675. You will be referred to a district biologist who will assess the problem and make control recommendations. If lethal control is recommended, then a permit application must be completed and sent to the U.S. Fish and Wildlife Service regional office along with a fee.
Nest Removal
In areas where a permit is required, the nest removal method will be specified by the permit. In California, old nests or nests under construction may be washed down with water or knocked down with a pole. Swallows are strongly attracted to old nests or to the remnants of deteriorated nests, so all traces of mud should be removed. During nest building, nest removal will require many days because cliff swallows persistently rebuild nests for most of the breeding season. They usually return the following year and the whole process must be repeated.
Exclusion
Exclusion refers to any control method that denies physical access to the nest site area. Exclusion represents a relatively permanent, long-term solution to the problem. In California, a permit is not required for this method if it is done before the birds arrive, during nest building when there are no eggs or young in the nest, or after the birds have left for the winter. If swallows have eggs or young in the nest, exclusion may not be used without a permit.
Netting can provide a physical barrier between the birds and the nest site. The mesh size should be 1/2 to 3/4 inch; however, 1 inch has been used successfully. If a plastic net is used, it should be attached so that it can be pulled taut. This prevents flapping in the wind, which looks unsightly and results in tangles or breakage at mounting points. The net should not have any loose pockets or wrinkles that could trap and entangle birds.
Attach netting to buildings before the birds arrive and leave it up permanently or remove it after the nesting season. Netting can be attached using tape, staples, or hooks on the eaves and the side of the building. An advantage of hooks is that the net can be taken down during the nonbreeding period or for maintenance of light fixtures, painting, etc. If staples are used, they should be rust-resistant to avoid unsightly rust stains on the building. For netting, a supporting framework of wooden dowels, wood laths, or metal rods along the edges will ease attachment to the hooks and create more even tension on the net. Netting may also be wrapped once or twice around wood laths and nailed directly to the building. It should extend from the outer edge of eaves down to the side of the building where protection from the elements given by the eaves is lost. Be sure there are no openings in the net where swallows might enter.
Some individuals have reported that hanging a curtain of netting from the eave will prevent nesting. The curtain should be 3 to 4 inches from the wall and extend down from the eave 18 inches or more.
Blocking the entrance will prevent cliff swallows from nesting inside buildings. Hang netting or strip doors of vinyl plastic or similar material across the entrance like a curtain, allowing passage of vehicles, materials, or people. Weighting the bottom of the netting will help keep it reasonably taut and in position during windy weather. Cliff swallows have been known to abandon nests inside a barn loft when the entrance was partially closed, reducing it to less than 8 x 8 feet.
Usually, swallows will not fly into a net but will stop and hover in front of it. If only that section of a building where swallows have nested is netted, the swallows will often choose alternative sites on the same structure. Therefore, any part of a building suitable for nesting must be netted. After the netting or wire mesh is installed, monitor the area for entry points and make necessary adjustments.
Other Methods
Nesting is sometimes discouraged through the use of metal projectors.These are sharp, needlelike wire or plastic devices generally installed along building ledges and windowsills to discourage birds from roosting. This method is not always successful in preventing swallows from nesting. In one instance cliff swallows learned to land on the metal spines and eventually built nests attached to them. Attach the sharp projectors to cover the area where swallows prefer to build nests, especially horizontally along walls protected by eaves. Additional projectors running vertically should be attached along interior corners. Once installed, projectors are left in place permanently.
Fiberglass panels that are 6 inches wide have been used to prevent nesting in some situations. The panels are installed between the eave and wall forming a smooth, concave surface that makes nest attachment difficult.
Modification of the surface where swallow nests would be attached sometimes effectively discourages nesting. Swallows prefer rough, uneven surfaces that provide a good foothold and suitable surface for nest attachment. Removing the rough surface of the wall and overhang can make the site less attractive to swallows. Attaching glass, sheet metal, or other very smooth-surfaced materials to the potential nest site can inhibit swallow nesting. A fresh coat of paint producing a slick surface may discourage nesting. Removing old nests and painting the area may discourage nesting the following year.
Other methods have shown little success or are unproven against cliff swallows. These include employing hawk, owl, or snake models or using taped alarm calls, noisemakers, revolving lights, and chemical roost repellents.