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In general, population growth roughly follows one of these trends: [1] Logistic growth leveling out at some carrying capacity. Overshoot ("boom" and "bust" cycles). Oscillation at or below the carrying capacity. Insect pest growth rates are heavily influenced by temperature and rainfall, among other variables.
where N is the biomass density, a is the maximum per-capita rate of change, and K is the carrying capacity of the population. The formula can be read as follows: the rate of change in the population (dN/dT) is equal to growth (aN) that is limited by carrying capacity (1 − N/K).
Between 950,000–1,000,000 of all described animal species are considered insects, so over 50% of all described eukaryotes (1.8 million species) are insects (see illustration). With only 950,000 known non-insects, if the actual total number of insects is 5.5 million, they may represent over 80% of the total, and with only about 20,000 new ...
Decline in insect populations. An annual decline of 5.2% in flying insect biomass found in nature reserves in Germany – about 75% loss in 26 years [1] Insects are the most numerous and widespread class in the animal kingdom, accounting for up to 90% of all animal species. [2] [3] In the 2010s, reports emerged about the widespread decline in ...
Economic threshold. In integrated pest management, the economic threshold is the density of a pest at which a control treatment will provide an economic return. [1] An economic Injury is the insect's population level or extent of crop damage at which the value of the crop destroyed exceeds the cost of controlling the pest. [2]
Alexander John Nicholson. Alexander John Nicholson (25 March 1895 – 28 October 1969) was an Irish Australian entomologist who specialized in insect population dynamics. He was Chief of the CSIR / CSIRO Division of Economic Entomology for 24 years and is credited with initiating the professional era in Australian entomology. [1]
This uses one organism to reduce the population density of a pest organism; it is a key element of integrated pest management. [156] [157] Biological control is favored because insecticides can cause harm to ecosystems far beyond the intended pest targets.
Insect migration is the seasonal movement of insects, particularly those by species of dragonflies, beetles, butterflies and moths. The distance can vary with species and in most cases, these movements involve large numbers of individuals. In some cases, the individuals that migrate in one direction may not return and the next generation may ...