Culturing Insects

Many species of insects are maintained routinely in culture for purposes ranging from commercial sale to scientific research and even conservation and reintroduction to the wild. As mentioned in section 1.2, much of our understanding of genetics and developmental biology comes from D. melanogaster, a species with a short generation time of about 10 days, high fecundity with hundreds of eggs in a lifetime, and ease of culture in simple yeast-based media. These characteristics allow large-scale research studies across many generations in an appropriate timescale. Other species of Drosophila can be reared in a similar manner, although they often require more particular dietary requirements, including micronutrients and sterols. Tribolium flour beetles (section 1.2) are reared solely on flour. However, many phytophagous insects can be reared only on a particular host plant, in a time- and space-consuming program, and the search for artificial diets is an important component of applied entomological research. Thus Manduca sexta, the tobacco hornworm, which has provided many physiological insights including how metamorphosis is controlled, is reared en masse on artificial diets of wheatgerm, casein, agar, salts, and vitamins rather than any of its diverse host plants.

The situation is more complex if host-specific insect parasitoids of pests are to be reared for biocontrol purposes. Not only must the pest be maintained in quarantine to avoid accidental release, but the appropriate life stage must be available for the mass production of parasitoids. The rearing of egg parasitoid Trichogramma wasps for biological control of caterpillar pests, which originated over a century ago, relies on availability of large numbers of moth eggs. Typically these come from one of two species, the Angoumois grain moth, Sitotroga cerealella, and the Mediterranean flour moth, Ephestia kuehniella, which are reared easily and inexpensively on wheat or other grains. Artificial media, including insect hemolymph and artificial moth eggs, have been patented as more efficient egg production methods. However, if host location by parasitoids involves chemical odors produced by damaged tissues (section 4.3.3), such signals are unlikely to be produced by an artificial diet. Thus mass production of para-sitoids against troublesome wood-mining beetle larvae must involve rearing the beetles from egg to adult on appropriately conditioned wood of the correct plant species.

Insects such as crickets, mealworms (tenebrionid beetle larvae), and bloodworms (midge larvae) are mass-reared commercially for feeding to pets, or as bait for anglers. Further, hobbyists and insect pet owners form an increasing clientele for captive-reared insects such as scarabs and lucanid beetles, mantises, phasmids, and tropical cockroaches, many of which can be bred with ease by children following on-line instructions.

Zoos, particularly those with petting facilities, maintain some of the larger and more charismatic insects in captivity. Indeed some zoos have captive breeding programs for certain insects that are endangered in the wild - such as the Melbourne Zoo in Australia with its program for the endangered Lord Howe Island phasmid (Dryococelus australis), a large, flightless stick-insect. In New Zealand, several species of charismatic wetas (outsized, flightless orthopterans) have been reared in captivity and successfully reintroduced to predator-free offshore islands. Among the greatest successes have been the captive rearing of several endangered butterflies in Europe and North America, for example by the Oregon Zoo, with eventual releases and reintroductions into restored habitat proving quite successful as interim conservation strategies.

Beekeeping for Beginners

Beekeeping for Beginners

The information in this book is useful to anyone wanting to start beekeeping as a hobby or a business. It was written for beginners. Those who have never looked into beekeeping, may not understand the meaning of the terminology used by people in the industry. We have tried to overcome the problem by giving explanations. We want you to be able to use this book as a guide in to beekeeping.

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