Latin Name: Passer Domesticus
The House Sparrow is a small, non-migratory, insectivorous and granivorous songbird native to most of Europe, the Mediterranean region, and much of Asia that is now the most widely distributed bird in the world. Originally introduced into New York City in 1852 as a control agent against the ravages of the Linden Moth, the House Sparrow’s population has since exploded, becoming one of the most abundant birds in North America. Strongly associated with human habitations, House Sparrows thrive in both urban and rural settings, typically avoiding extensive woodlands, grasslands, and deserts away from humans. Large scale flocking of House Sparrows overwhelms urban spaces not only visually, but also does structural damage to buildings (uric acid in fecal matter), clogs drains and poses a potential health risk for residences. House sparrows are one of very few bird species in North America that are not protected by the law.
Adult House Sparrows are small; their typical range is 13-16 cm (5-6.6 in) in length. Females and nestlings are pale brown and grey, whilst males are black-throated with a reddish chestnut back and grey underparts. During breeding times beaks of both sexes darken in colour. During the winter, the male’s black markings become greyer, and the beak goes from black to a more yellowish colour. The adult weight range is 0.85–1.39 oz (24-39.5 g).
Remarkably, a breeding pair can grow to over 2000 birds in 2 or 3 years if left unchecked. Breeding pairs only mate for a single season, with an average of three broods per season with each clutch containing 4-7 eggs, House Sparrows spawn an average of 20 offspring a year. Eggs are white, pale blue or pale green with a few grey or brown dots. The same nest will often be occupied by several different females in a given year. After a two week incubation period, sparrows will take their first flights in about 15 days and gather in small flocks once they’ve left the nest. Flocks amalgamate and result in crowd sizes of several hundred birds.
House sparrows are non-migratory, but in cold climates can show movement between rural/suburban breeding sites and to warmer winter roosting sites within the city. House sparrows are aggressive birds and will often force native birds away from their territories during flocking periods. House Sparrows are well-adapted to living around humans, frequently living and breeding indoors, especially in factories, warehouses, and zoos, preferring enclosed spaces such as shutters, drainage piping, building rafters and corrugated metal siding, only nesting in trees as a last resort. The nesting material typically consists of sticks, with an inside lining of grass, string, fabrics or straw, the nest can often hold several families.
Predators of the sparrow include domestic cats, hawks, owls, and many other predatory birds and mammals.
House Sparrows usually host a variety of ectoparasites that will invade the structures that bird nests are in, or, on when for whatever reason, nests are vacated. When lacking a consistent food source, these mites, lice and ticks may begin to feed on humans, pets and livestock and can transmit dangerous pathogens. House Sparrows are reservoir hosts; the commonly recorded bacterial pathogens of the House Sparrow are often those common in humans and include Salmonella and E. coli. Salmonella epidemics in the spring and winter can kill scores of sparrows. The House Sparrow also hosts Avian Pox and Avian Malaria, which it has spread to the native forest birds of Hawaii. House sparrows are a factor in the spread of fowl cholera, Newcastle disease, Avian Tuberculosis, Turkey Blackhead, Canary Pox, Eastern equine encephalitis, Pullorum, Canary Pox, Anthrax and various worms, fungal and protozoan parasites. The West Nile virus, which most commonly infects insects and mammals, goes dormant in birds like the House Sparrow, surviving winters in temperate areas. The House Sparrow is usually regarded as a pest since it consumes agricultural products and spreads disease to humans and their domestic animals. Even birdwatchers often hold it in little regard because of its molestation of other birds.
Sparrow pest management and population control demands an integrated approach to pest management involving physical modifications to the property: The removal of a food source, the use of netting, wire and spikes to trap and remove sparrows from roosting sites or to render roosting sites inaccessible. Scare tactics can include the implementation of predatory bird sounds and scarecrows and the use of actual predators, i.e., Peregrine Falcons. Nests must be removed and the structure treated for fleas, mites and lice that will migrate in search for a new host body food source. Although in Toronto there is no bylaw that prevents a person from feeding wild or domesticated birds or animals, Toronto Municipal Code 629 places onus on the tenant to keep their balcony clean of potentially harmful bird droppings. Avicides are widely banned from use due to their non-selective nature and to avoid the risk of harming predator bird populations.