Wednesday, July 25, 2007

Not Associated With Disease Transmission

Unlike most other flies, BSF adults do not go into houses, they do not have functional mouth parts, they do not eat, they do not regurgitate on human food, and therefore, they are not associated in any way with the transmission of disease. Adults do not bite, bother or annoy humans. Their activity is limited solely to mating and egg-laying. Note that it is only the females that visit waste, not the males, since males do not lay eggs. When females visit waste to lay eggs, they never actually come into contact with the the waste. They lay their eggs above or to the side, never on, otherwise they run the risk of their eggs being eaten along with the waste.

Life Cycle At A Glance

A female produces about 900 eggs in her short life of 5 to 8 days. Housefly adults, by contrast, live up to 30 days, and during this long period, they must eat, and in so doing, they are actively engaged in the spread of disease. Their naturally short life span is the reason why they are not vectors of human pathogens. BSF eggs are relatively slow in hatching: from 102 to 105 hours. The newly hatched larvae have a light cream color, and crawl onto the waste, where they begin to consume it with amazing speed. Under ideal conditions, it takes about two weeks for the larvae to reach maturity. If the temperature is not right, or if there is not enough food, this period of two weeks may extend to several months. The ability of the BSF larva to extend its life cycle under conditions of stress is a very important reason why it may be used for waste disposal processing. BSF larvae pass through five stages or instars. Upon reaching maturity, they are about 25 mm in length, 6 mm in diameter, and they weigh about 0.2 grams. The dormant puparium is dark brown to charcoal gray in color. These larvae and pupae are extremely tough and robust. They can survive under conditions of extreme oxygen deprivation.

Friday, July 20, 2007

Attracting Songbirds

Mature larvae are an ideal food for attracting bluebirds, orioles, cardinals, goldfinches, thrushes, catbirds, woodpeckers, nuthatchers, chickadees, and warblers to the back yard garden. The logical and most common means of offering this nutritious food is to use a special bluebird feeder, or similar unit that has been designed to distribute mealworms to birds. Look for units that possess a sloped, overhanging lid or roof which will prevent runoff of rain or dew into the feeding area. Drainage holes and critter guards are also beneficial to a functional feeder.

Thursday, July 19, 2007

Residential Food Waste Diversion

BSF larvae are voracious consumers of food scraps. Decomposition via digestion can be measured in hours, rather than weeks or months. Wastes are reduced by up to 95% of original weight and volume. Despite their insatiable appetite in the larval stage, BSF are a relatively innocuous species of native arthropod - harmless to humans, pets and wildlife. Adult BSF possess no functional mouth parts or stingers, so they are not capable of feeding, biting, or inflicting pain. They are notable at mitigating the presence of the common house fly and other filth bearing flies - a definite plus for back yard composting.

Benefits to Vermiculture

One of the drawbacks of raising redworms is the speed at which food scraps are processed into castings. Before the worms can begin their feast, it is necessary for the beneficial micro-organisms to begin breaking down the scraps - redworms do not eat fresh foods, only ones that are decomposing. This can take a great deal of time, especially on new setups. The surface to volume ratio is also a factor that affects the rate of digestion. The smaller the particle size, the faster the decomposition. Most organic kitchen waste is not ground up sufficiently to maximize decay, and thus the transformation into casting can be painfully slow.

BSF larvae are notably different that redworms because they will actively consume fresh scraps immediately, without the need for pre-decomposition. BSF digestion is focused on the proteins and fats in the waste pile - most of the cellulosic materials do not get eaten by the larvae, though physical chopping into smaller pieces does occur. The remaining cellulose fraction is targeted quickly by fungi and composting bacteria at the lower levels of the pile. The black, friable residue that remains after digestion by the larvae is of ideal consistency, particle size and nutrient balance to be fed directly to an active vermiculture system. The end result of this two-tiered processing is the production of redworm castings at a faster rate than using redworms alone.

Wednesday, July 18, 2007


Thank you for visiting this weblog about the Black Soldier Fly. There is a paucity on the internet of relevant and practical information on BSF and its sustainable applications. This site was created for the purpose of pooling existing knowledge, in the hope that it may become the definitive clearinghouse for online discussion about Hermetia illucens. Please contribute or leave a comment.

Sincerely, Moderator