The domestic cricket, Acheta domestica, can be both hardy and delicate. Many people have success keeping colonies to supply their animals with food, while others seem to have trouble keeping small numbers alive on a weekly basis. Crickets eat nearly anything and are easy to breed, yet an entire colony can be wiped out in hours if conditions are not perfect. These massive die-offs, which are common when large groups of crickets are kept, can be avoided with a few simple rules.
Poor ventilation, crowded conditions and high humidity are the most common reasons for cricket colony failures.
Domestic crickets are most likely native to southwestern Asia, but their exact origin is unclear. The movement of humans over continents and across oceans has established populations throughout the world, usually in close association with people.
In the U.S., most common crickets belong to the genus Gryllus and are collectively known as field crickets. These species thrive in damp conditions, whereas domestic crickets quickly sicken and die unless kept dry.
Always choose the largest possible enclosure for your cricket colony. Poor ventilation, overcrowding, and high humidity are the most common reasons for cricket colony failure. Crickets excrete large volumes of solid waste which is quickly colonized by harmful fungi and bacteria. Cramped quarters, even if well-ventilated, allow for the buildup of moisture released in respiration. The resulting dampness can lead to fatal fungal diseases. Crowding also increases aggression and cannibalism.
Large plastic storage bins or garbage cans make the best enclosures. Most of the plastic from the bin's sides and top should be cut away and replaced with aluminum mosquito screening. The screen can be secured to the bin with aquarium silicone or duct tape. As crickets will chew on dried adhesives like silicone or tape, these should be applied on the outside of the bin.
Ample cross ventilation helps dissipate moisture and is essential for the colony's survival. Aquariums, plastic terrariums, and cricket cages can also be used, but top ventilation alone will limit the number of crickets that can be kept.
The bottom of the enclosure should be left bare to aid cleaning. It is important to increase the surface area by providing material for the crickets to climb upon. Cardboard egg crates, paper towel rolls, and crumpled newspapers work well, but must be replaced as they are soiled.
Heat and Humidity
Cricket activity level and appetite increases as temperatures rise. To limit waste production, large groups should be kept at 70-72°F. At this temperature, they will be active enough to feed and thus pass on nutrients to your animals, but their metabolisms will be slow enough to limit unsanitary conditions.
Warmer temperatures, up to 90°F, are acceptable. However, at high temperatures crickets eat enormous quantities of food and the enclosure will be harder to keep clean and dry. Chirping increases with temperature as well, although some noise is to be expected when keeping crickets.
Humidity should be kept low. Never spray the enclosure, as dampness can quickly kill the entire colony. Dry conditions will also limit odors.
In order to improve their dietary value, crickets should be allowed to feed on nutritious foods for at least 2 days prior to being offered to other animals. A mixture of cricket food, tropical fish flakes, dry milk, and a calcium powder can be used as the bulk of their diet. A protein source such as dry dog food should be added, as low protein diets have been linked to increased cannibalism.
Oranges, apples, kale, yams, carrots, and other produce should be offered regularly and removed before it becomes moldy or spoils. Fruits and vegetables provide an additional variety of nutrients as well as a convenient water source.
As stated above, produce can make a great water source as long as it is fresh. Other methods of watering crickets must also not lead to an increase in humidity. Standing water is not an option, as crickets will easily drown, and absorbent cotton added to the water dish will become quickly fouled. Cricket gel, water pillows, and water dispensers designed for crickets are preferable but still must be replaced or cleaned regularly.
Daily Care and Maintenance
Check daily to remove moldy produce, dead crickets, or soiled egg crate. Dry food should also be checked daily and replaced if necessary.
Once a week the enclosure should be emptied and cleaned with warm bleach water (1 cup bleach per gallon) and allowed to dry thoroughly, preferably in the sun.
Domestic crickets breed readily, with the best results at 82-90°F. Females will deposit eggs in bowls filled with 2 inches of moist sand or soil. These bowls should be removed often, as crickets will eat their own eggs. Hatching occurs in 1-2 weeks at 85-90°F, resulting in tiny crickets that can be fed to smaller frogs and juvenile lizards. Rearing crickets to adulthood takes 2-3 weeks and is not worth the effort for most keepers.
Some people who work with crickets develop an allergy to the associated dander and dust over time. A disposable face mask may be useful; please consult your doctor if you are concerned about this possibility.