Quantitative Aspects

Though the amount of food available might be considered as an important regulator of insect abundance, it has been found in natural communities that populations do not normally use more than a small fraction of the total available food. This is primarily because other

FIGURE 23.1. An example of a food web in a terrestrial ecosystem, showing the importance of insects. [From P. W. Price, The concept of the ecosystem, in: Ecological Entomology (C. B. Huffaker and R. L. Rabb, eds.). Copyright © 1984 by John Wiley and Sons, Inc. Reprinted by permission of John Wiley and Sons, Inc.]

FIGURE 23.1. An example of a food web in a terrestrial ecosystem, showing the importance of insects. [From P. W. Price, The concept of the ecosystem, in: Ecological Entomology (C. B. Huffaker and R. L. Rabb, eds.). Copyright © 1984 by John Wiley and Sons, Inc. Reprinted by permission of John Wiley and Sons, Inc.]

components of the environment especially weather but including, for example, predators, parasites, and pathogens, usually have a significant adverse effect on growth and reproduction. Other features of insects may, however, be important in this regard. Many species, especially plant feeders, are polyphagous. Thus, when the preferred food plant is in limited quantity, alternate choices can be used. Among endopterygotes, larvae and adults of a species may eat quite different kinds of food, and in some species such as mosquitoes the food of the adult female differs from that of the adult male.

Two situations may occur in which the quantity of food limits insect distribution and abundance. In the first, there is no absolute shortage of food, but only a proportion of the total is available to a species. Thus, there is said to be a "relative shortage" of food. Various reasons may account for the food not being available. (1) The food may be concentrated

FIGURE 23.2. An example of a food web in a freshwater ecosystem, showing the importance of insects. [From P. W. Price, The concept of the ecosystem, in: Ecological Entomology (C. B. Huffaker and R. L. Rabb, eds.). Copyright © 1984 by John Wiley and Sons, Inc. Reprinted by permission of John Wiley and Sons, Inc.]

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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