The Domestic, Brown or House Cricket, Acheta domesticus, is the most widely-used live food for reptiles, amphibians, tarantulas, scorpions and other pets. At once hardy and delicate, it eats just about anything and is easy to breed, yet a colony can be wiped out in hours if conditions are not perfect. Whether you need only to keep a few alive so that they can feed for several days (thereby increasing their nutritional value) or plan to save money by ordering in bulk or breeding your own crickets, die-offs can be avoided if you follow a few simple rules.
Primary Concerns
Poor ventilation, crowded conditions and high humidity are the most common reasons for cricket colony failures. These three factors are related to one another, and will be discussed below.
Natural History
Domestic Crickets are native to southwestern Asia. Escapees have established populations throughout the world, usually in close association with people. Their taxonomic order, Orthoptera, contains over 20,000 grasshoppers, katydids and related insects.
The USA is home to over 120 cricket species; my favorites, the bizarre Mole Crickets, tunnel below-ground with spade-like front legs (please see photo). Over 3,000 species have been described worldwide. New Zealand’s “super cricket”, the Giant Weta, is the world’s heaviest insect…at 70 grams, it weighs as much as a House Sparrow!
Housing
Always choose the largest possible enclosure for your colony. Crickets excrete copious waste products, which are quickly colonized by harmful fungi and bacteria. In addition, cramped quarters allow for the buildup of moisture released via respiration, which leads to fungal diseases. Crowding also increases cannibalism.
Plastic storage bins or garbage cans make the best enclosures for cricket colonies. Most of the plastic from the bin’s sides and top should be cut away and replaced with aluminum mosquito screening (adults chew through plastic screening). The screening can be secured with aquarium silicone or duct tape, which should be applied to the outside of the enclosure. Ample cross-ventilation helps dissipate moisture; top-only ventilation will limit the number of crickets that can be kept.
Screen-topped aquariums and commercial cricket cages can also be used, but they will support fewer crickets than ventilated storage containers.
Substrate
The bottom of the enclosure should be left bare to facilitate cleaning. Cardboard egg crates, paper towel rolls and crumpled newspaper should be used to increase the available surface area.
Heat and Humidity
Cricket appetites increase as temperatures rise. To limit waste production, large groups should be kept at 70-72 F. They will feed at these temperatures but their metabolisms will not be racing.
Warmer temperatures, up to 90 F, are acceptable. However, the enclosure will be harder to keep clean and dry, and fungal/bacterial growth will speed. Chirping (a/k/a noise!) also increases with temperature.
Humidity should be kept low. Never spray the enclosure, as dampness can cause massive die-offs.
Feeding
In order to improve their dietary value, crickets should be provided nutritious foods for at least 2 days prior to being offered to pets. A mixture of commercial cricket pellets, tropical fish flakes, dry milk and powdered reptile calcium supplements works well. Food should be placed in jar lids or shallow bowls.
Oranges, apples, kale, yams, carrots and other produce should be offered, but care must be taken to limit mold growth; use small amounts until you can judge how much will be consumed before spoilage.
This cricket diet will ensure a nutritious meal for your pets, but cat chow, rabbit pellets and other foods have also been used with success. Low protein diets have been linked to increased cannibalism.
Water
Crickets need to drink often, but will drown in standing water. Gravel, sponges or cotton placed in water bowls will prevent this, but these quickly become fouled. Commercial gel cubes or water pillows are preferable.
Another option is to use fruits and vegetables, which also provide valuable nutrients, as a water source. Oranges are particularly good in this regard. If orange pieces dry out quickly, try cutting several “entry holes” into an intact orange to slow the drying process.
Daily Care and Maintenance
Daily chores include checking for mold and damp substrates and removing dead crickets and droppings that have accumulated in food bowls.
The enclosure should be emptied and cleaned weekly. To empty, shake the egg crate or other substrate (to dislodge living crickets) and discard. Then tilt the cricket bin one side up and add some fresh newspaper…most of the living crickets will climb onto this. These crickets can be retained and put back into the clean container. Place the remaining debris in a plastic bag and freeze, so as to euthanize injured individuals. Avoid transferring dead or injured crickets to a clean enclosure.
The cricket bin should then be cleaned with warm water and bleach (1 cup/gallon) and allowed to dry thoroughly.
Breeding
Domestic Crickets breed readily, with the best results being had at 82-90 F. Females will deposit their eggs in bowls stocked with 2 inches of moist sand or earth. These should be removed often, as adults love snacking on their own eggs. Hatching occurs in 1-2 weeks at 85-90 F, and sexual maturity is reached in 2-3 months.
Health Considerations
Some people who work with crickets develop allergies over time. A disposable face mask may be useful; please consult your doctor for details.
Further Information
Rearing Grasshoppers and Locusts
Mate Guarding in Field Crickets
Domestic Cricket image referenced from wikipedia and originally posted by G U Tolkeihn
Mole Cricket image referenced from wikipedia and originally posted by Sharadpunita