Biological control of invertebrate and vertebrate pests

Among the pests covered in this book, animals with and without backbones are often extremely obvious to humans. Vertebrates are animals with backbones while invertebrates are all multicellular animals without backbones, thus including a broad array of organisms from worms to dragonflies to lobsters. While both vertebrate and invertebrate animals can be pests that need to be controlled, they differ in the diversity of problems they cause as well as in the potential means for using biological control against them. Invertebrates The invertebrates covered in the following chapters will principally include insects and mites, both belonging to the jointed-legged animals, the arthropods. Plant parasitic nematodes are the focus of biological control efforts but will be covered in Chapter 16 and 17 because they are historically most commonly considered along with plant pathogens. Among the invertebrates, the arthropods targeted most tirelessly for biological control are pests in terrestrial systems, although some aquatic pests are targeted. It has been estimated that there are from less than 5 million to as many as 80 million species of insects alone. Such a huge number of species is accompanied by a great diversity in life-history strategies. Controlling pestiferous insects and mites has most certainly always been a concern of humans. However, it is difficult to quantify the injury or damage incurred by insects around the world. In 1997, it was estimated that in the USA alone each year $7.7 billion of crops are lost due to insects.