Soil Dwelling and Scavenging Insects

By their very habit the majority of soil-dwelling insects are ignored by humans. Only those that adversely affect our well-being, for example, termites, wireworms, and cutworms, normally "merit" our attention. When placed in perspective, however, it seems probable that the damage done by such pests is greatly outweighed by the benefits that soil-dwelling insects as a group confer. The benefits include aeration, drainage, and turnover of soil as a result of burrowing activity. Many species carry animal and plant material underground for nesting, feeding, and/or reproduction, which has been compared to ploughing in a cover crop.

Many insects, including a large number of soil-dwelling species, are scavengers; that is, they feed on decaying animal or plant tissues, including dung, and thus accelerate the return of elements to food chains. In addition, through their activity they may prevent use of the decaying material by other, pest insects, for example, flies. Perhaps of special interest are the dung beetles (Scarabaeidae), most species of which bury pieces of fresh dung for use as egg-laying sites (Figure 24.3). Generally, the beetles are sufficiently abundant that a pat of fresh dung may completely disappear within a few hours, thus reducing the number of dung-breeding flies that can locate it. Furthermore, the chances of fly eggs or larvae surviving within the dung are very low because the dung is ground into a fine paste as the beetles or their larvae feed. Likewise, the survival of the eggs of tapeworms, roundworms, etc., present in the dung producer, is severely reduced by this activity.

In Australia there are an estimated 22 million cattle and 162 million sheep that collectively produce 54 million tonnes of dung (measured as dry weight) each year! The cattle dung especially provides food and shelter for many insects, including the larvae of two fly pests, the introduced buffalo fly (Haematobia irritans exigua) in northern Australia and the native bush fly (Musca vetustissima) in southeastern and southwestern areas of the country. Further, because of the generally dry climate, the dung soon dries and may remain

FIGURE 24.3. (A) A dung beetle, Sisyphus rubrus, with its ball of dung which is rolled away from the dung pad and then buried. This southern African species was introduced into Australia in 1973; and (B) diagrammatic section through nest of the Australian native dung beetle Onthophagus compositus, which colonizes the dung of kangaroos, wallabies, and wombats. [A, photograph by J. Green. By permission of the Division of Entomology, CSIRO. B, from G. F. Bornemissza, 1971, A new variant of the paracopric nesting type in the Australian dung beetle, Onthophagus compositus, Pedobiologia 11:1-10. By permission of Gustav Fischer Verlag.]

FIGURE 24.3. (A) A dung beetle, Sisyphus rubrus, with its ball of dung which is rolled away from the dung pad and then buried. This southern African species was introduced into Australia in 1973; and (B) diagrammatic section through nest of the Australian native dung beetle Onthophagus compositus, which colonizes the dung of kangaroos, wallabies, and wombats. [A, photograph by J. Green. By permission of the Division of Entomology, CSIRO. B, from G. F. Bornemissza, 1971, A new variant of the paracopric nesting type in the Australian dung beetle, Onthophagus compositus, Pedobiologia 11:1-10. By permission of Gustav Fischer Verlag.]

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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