Western Pest Services - Pest Library

Pest Library

Blow Fly, Bottle Fly
Calliphora spp., Phaenicia spp., etc.
.

Class:

Insecta

Order:

Diptera

Family:

Calliphoridae

Size:

Blow fly and bottle fly adults are about 1/8-5/8 in (4-16 mm) long, the size of a house fly, or slightly larger. Mature larvae are about 3/8-7/8 in (9-22 mm) long.

Characteristics:

Blow flies and bottle flies have sponging mouthparts; antennae are feathery, at least on the bottom two thirds. Larvae are eyeless, legless, tapered from large, rounded rear segment to head, which is a pair of dark hooks.

Color:

Adults are partly or wholly metallic blue, green, or dull brassy, sometimes black. Larvae are pale yellow to white.

Geographic Range:

The black blow fly, shiny bluebottle fly, and bluebottle fly are found throughout the United States, but the last is more common in the northern part of the U.S. and in Canada. The bronzebottle fly occurs in the southern U.S., and greenbottle flies are found mostly in the northern U.S., southern Canada, and commonly in the midwestern U.S.

Comparison with other species:

Cluster fly has a dull body, tan to brownish black, with golden hairs on thorax. Secondary screwworm fly has bluish green body, orange head, reddish legs, and 3 black stripes on thorax. Screwworm fly has metallic black body, legs shiny green-black, 3 black stripes on thorax (middle one shorter). Dump flies have bluish black to shiny and bronzy black body. Flesh fly and House fly have dull gray and black bodies, and thorax with 3 or 4 black stripes.

Habitat:

Same as food source!

Food:

Meat; animal carcasses, especially those of birds and other small animals; excrement; decaying vegetation; garbage.

Biology:

Females lay their eggs on material which larvae will eat. Larvae may feed on the surface, then burrow into less decayed material underneath. They go through 3 instars, leaving the food material in order to pupate. Most species pupate within the top 2" of soil. Usually they overwinter as mature larvae or pupae. Development time from egg to adult varies, depending on species and temperature conditions, but usually takes between 10 to 25 days.

Invasion:

Blow and bottle flies are most active on warm, sunny days. They rest on cool or cloudy days. They are attracted to light coming through windows. Some species are strong fliers, such as some black blow flies that were found 4-28 miles from their starting point.

Damage:

Bottle flies and blow flies transmit disease.