The House Sparrow, Passer domesticus, is not native to North America and in fact it was introduced in the 1850s from England. It was mistakenly thought that it would reduce insect pests to crops. It is now one of the most abundant birds in North America and the most widely distributed bird on earth. They are not actually sparrows but Old World Weaver Finches, which are noted for their resourceful nest building.
Biology & Damage
Breeding season for house sparrows begins early in the spring and sometimes even in midwinter. They are very prolific with each pair producing up to four broods a season. House sparrows are nonmigratory and are so closely tied to human activity that they are only found in the vicinity of human habitation.
House Sparrows are very aggressive and are the number one reason for the decline in the Purple Martin and Eastern Bluebird in our eastern and southern states. In Montana they are responsible in part for the decline of other cavity nesting birds. The aggressive nature of the House Sparrow also results in their driving away more desirable song birds from feeders and other locations. Most House Sparrow damage is related to their nesting and feeding habits. They are very gregarious, nesting and congregating in large numbers. In these situations they are a considerable nuisance, and often cause unsanitary or odorous conditions. Droppings can kill ornamental vegetation and damage finishes on vehicles. House Sparrows are also a factor in the spread of several diseases such as chlamydiosis, New Castle disease, salmonellosis, toxoplasmosis and transmissible gastroenteritis. House Sparrows also carry parasites, insects, fleas, mites and fowl ticks.
Exclusion
To keep sparrows out of nesting cavities or other sites, the openings should not be larger than ¾". Any sparrows found in nest boxes should be immediately removed. Openings greater than ¾"; around houses and other buildings should be screened off or blocked to prevent entrance. All outside structures such as air conditioners should be mounted with no open spaces between it and the structure. Exclusion of sparrows around bird feeders is difficult. However, do not scatter birdseed on the ground where they prefer to scavenge. Avoid cheap mixed bird seed that contains a large amount of filler grains, such as milo, millet or cracked corn. Concentrate on using sunflower seeds which are preferred by many songbirds, but not by house sparrows.
Repellents
If sparrows are using ledges, window sills, and roof lines for roosting or access to nesting cavities, these areas can be protected using “porcupine wires”. The wire has multiple projections that prevent birds from roosting, and it can be attached directly to structures. There are also a number of “sticky” substances that can be applied to prevent birds from roosting.
Trapping
A number of traps have been found effective for controlling sparrows. Live traps such as funnel entrance, automatic triggered traps, mist nets, nest box traps and sieve traps are all effective. These have the added advantage as any protected songbirds can be released. Funnel type entrance traps will require no monitoring as the birds trap themselves and continue to enter the trap. Essentially the birds enter the trap through a funnel with sharp projections that prevent them from going back out. Grain scattered in the trap and even a small mirror will attract sparrows. Leave a number of trapped sparrows in the trap as decoys. These decoys will attract even more sparrows to the trap. Ten sparrows in a trap, seems to be the most effective number for luring more sparrows. Sieve traps with bait on the ground underneath are also effective. These simple traps are a sieve supported by a stick and drops when the stick is pulled out. However, they have to be monitored to trip. Another trap is one which attaches or fits to a cavity nest, such as on the bottom of a bluebird house. Automatic traps such as the “Hava Hart” sparrow trap will capture individual sparrows as they enter.
Check your local ordinances and decide if these types of control are not only legal, but safe within your area.
Chemical Control
Several different chemicals have been developed and are designated for sparrow control and should be used only if exclusion, trapping and other methods don’t work. Avitol baited wheat or corn is effective on sparrows. Federal and state law protect all songbird species except house sparrows, starlings and pigeons. Therefore, use must read and follow label directions and target only those three nuisance species. Many of these chemical are poisons that are potentially harmful to people and pets, are dangerous to other birds and can create many other problems. Consequently, we do not recommend chemical control or poisons for most situations. Many of the control products mentioned here can be purchased or ordered through nurseries, garden centers and farm supply stores.
Nest Destruction
Good old fashion harassment by spraying with water or oil, especially the nests, and continual removal of nests is the most effective technique, but can be time consuming. Nest should be removed, and all nestlings and eggs destroyed. To be effective, removal of eggs or nestlings from nest cavity nests, needs to be repeated every 2 weeks, as the birds will re-nest immediately.
Scare or Frightening Devices
Acoustical repellents such as alarm or distress notes are not successful. Devices such as decoy owls, rubber snakes or balloons are usually ineffective. Additionally, noise making devices have very little effect on sparrows.
Shooting
In rural areas, shooting can be effective in removing, harassing and discouraging sparrows from using an area. It is especially important to remove the males as they have a strong attraction to a particular nest site, attracting females to the site. It is illegal and unsafe to discharge firearms within many cities, but it may be legal if done with air rifles or pellet guns.
