First published in Herpetoculture House Digital Magazine vol. 3 issue 4
The Dubia roach (Blaptica dubia) also known as the Guyana spotted roach, Argentine roach, or orange spotted roach is a popular soft-bodied insect used to feed many species of insectivorous reptiles. Dubia roaches gained popularity as an alternative to crickets due to their higher nutritional content and lack of noise and odor. They are native to Central and South America and cannot survive outside of tropical conditions even indoors which means there is no risk of any home infestations as some people have feared however they are illegal to own in the state of Florida.
Dubia are a medium size roach with nymphs born measuring only 2 millimeters and adults reaching maximum lengths of 4.5 centimeters or 1.8 inches. They are sexually dimorphic with mature males being slightly smaller than females and having large fully developed wings that range in color from brown to black. Females are bulkier, developing only small wing stubs, and vary in color from an almost solid black to dark brown with orange markings. Their lifespan is typically about 9 months for males and 12-18 months for females. As with many insects Dubia roaches will need to shed their exoskeletons in order to grow, through a process known as molting.
Dubia colonies are typically housed in large opaque plastic totes with either drilled air holes or screened cut-out sections and provided with stacked egg crates to live and hide in. Dubia cannot climb smooth surfaces and although males have wings, they are unlikely to fly unless they are able to launch themselves from a suitable height in highly favorable conditions making smooth sided totes perfect for housing them. Coming from tropical areas they favor high temperatures and mid-level humidity. They can be maintained at temperatures ranging from 75 to 95 degrees Fahrenheit but temperatures around 80 degrees are optimal especially for breeding purposes. At higher temperatures they will mature and breed quicker but it will also shorten their lifespans conversely they will cease breeding activities at temperatures below 68 degrees. The best way to provide heat without drying out the captive environment would be to use a low level heat pad or thermostatically regulated heat tape. An overhead light bulb or heat emitter tends to dry out the environment plus roaches prefer darkness over light. Dubia roaches require adequate levels of humidity in order to molt properly however care should be taken to ensure that conditions are not allowed to become too wet and stagnant which would promote detrimental mold growth and even attract pests such as flies, gnats, and mites. Humidity levels of 50 to 60 percent are usually satisfactory and humidity can be raised by lightly misting the colony with water only when absolutely necessary such as roaches dying off from an inability to complete the molting process.
They can be sustained on commercially available and home made meals which are typically a ground mixture containing a variety of grains and other nutritious ingredients including vitamins and minerals, especially calcium. Other staple food sources come from cereal grain, dog/cat food, fish flakes or pellets, and poultry feed. Commonly available commercial foods include Repashy's Bug Burger and Fluker's cricket diet. They should also be regularly supplemented with fresh fruits and vegetables. True to their nature as roaches, Dubia will eat just about anything but the more nutritious the foods they eat, the higher their nutritional value as feeders. Water can be provided in gel form made from polymer water crystals although if they are consistently provided with fresh fruits and vegetables they are able to derive moisture from these sources also. Uneaten fresh foods should be removed every 24 to 48 hours to prevent spoilage, and the growth of mold and bacteria.
Roach bins should be cleaned every 3 to 6 months by replacing soiled egg crates and filtering out the waste products known as frass. The easiest and quickest way to sift out the frass without losing any of the smallest nymphs is to drill 9/64 inch holes in a bucket and use that as a sifter. This will allow the frass to fall through the holes but not the small nymphs and the roaches will also not be able to climb out of the bucket easily. Other methods include using a mesh colander or sieve. Beneficial “cleaning crew” insects such as dermestid and darkling beetles may also live with the Dubia colony and will help to reduce waste by eating frass and left over food.
When provided with suitable captive conditions and proper nutrition Dubia roaches are quite prolific with females capable of producing one egg sack every 1.5 to 2 months. Breeding is initiated when a male deposits a sperm packet inside the female. The females then lay an egg sack which is incubated ovoviviparously inside the female's body which will produce between 20 to 40 nymphs in approximately 28 days. Dubia roaches appear to give live birth because the nymphs hatch inside the female and emerge fully formed. Nymphs reach sexual maturity in about 4 to 6 months.
Tips and tricks
It has been reported that feeding foods such as bread or oranges spurs reproduction.
12 to 24 hours prior to being used as feeders Dubia roaches should be “gut loaded” by feeding them nutritious fresh foods. The nutrition derived from these foods will be passed on to the reptiles that eat the Dubias.
Dubia should not be fed a high protein diet such as provided by feeding solely dog or cat foods as Dubia roaches retain uric acid in their bodies rather than excreting it as waste. Too much retained uric acid is not only fatal to the roaches especially mature adults but also causes gout in reptiles like crested geckos when roaches are used as feeders.
When feeding off adult Dubias, feed off excess males first leaving a ratio of one male to three or four females which will eliminate any territorial disputes between males resulting in low reproductive productivity and even death.