Mammals and birds as agricultural pests: a global situation

On the globe there are approximately 7 thousand species of pests injuring agricultural crops. Because of pests’ activity from 33 % (D. Geinrikh et al., 2003) to 40 % (D. Pimentel et al., 1999) of world agricultural products are lost with annual financial losses estimated at $ 244 billion (D. Pimentel et al., 1997). In spite of the fact that the consequences of plant diseases and harmful insects for plant growing and forage production are discussed more often, economic loss caused by mammals and birds, is quite significant. It surpasses substantially losses put by nematodes, mites and molluscs, though far less than caused by harmful insects. As a whole it is to be noted that size of damage from mammals and birds as agricultural pests decreases gradually, remaining, however, still high. The reason of it consist both in application of modern scientific-design development (new technologies of harvesting, methods of pest control, etc.) and decreasing of populations size of wild animals due to reduction of their area and deterioration of the conditions of the habitat. As a preferred group of animals - agricultural pests, rodents were chosen. Their impact on condition of such branches, as production of grain, forage grasses and ensilage crops as well as vegetable growing, orcharding, and melon-growing is described. In California the annual economic loss from Spermophilus beecheyi at grain production is $ 8-12 million (S.A. Shwiff et al., 2009). Methods of struggle with rodents are presented. Other types of mammals, the most significant from the standpoint of their injuriousness are described. Information on their composition in a series of world regions is presented. For instance, they are deer, raccoons, and coyotes in the USA, and wild boar, bear and some ungulates in forest temperate zone. The figures of financial loss from them in some countries are given. Impact of plant-eating and omnivorous species of birds on grain-growing, gardening, vegetable growing, seed farming, and breeding of new cultures of plants is considered. In Australia more than 60 avian species are the pests of garden plantings, which cause the annual material loss of $ 300 million (Yu.M. Markin, 2008). The species of birds the most harmful on a global scale are listed, the figures of economic losses from them for a series of countries are presented.