Population and Community Ecology
Population ecology is the objects of study of which are the change in the number of populations, the relationship of groups within them. Within the framework of population ecology, the conditions under which populations are formed are being ascertained. It describes fluctuations in the numbers of different species under the influence of environmental factors and establishes their causes. The main factors that effect on the size of population are density, abundance and distribution (Friedl, 2019).
In this experiment were used few methods to estimate the population of the species: Removal method and Mark-Recapture method.
This method is very convenient for estimating the number of small organisms, especially insects, on a certain part of the meadow or in a certain volume of water. With a wave of a special grid, animals are caught, the number of caught is recorded and not released until the end of the study. Then the capture is repeated three times, with each time the number of animals caught decreases. When plotting, the number of animals caught at each catch is noted against the total number of animals caught earlier.
This method involves trapping an animal, marking it in such a way as not to harm it, and releasing it where it was caught, so that it can continue normal livelihoods in the population. For example, gill covers of nets caught by fish are attached to aluminium plates, or rings are put on the legs of nets caught by nets. Small mammals can be marked with a paint, incise the ear or cut off the fingers, arthropods are also marked with paint. In any of the cases, a form of coding can be applied that allows one to distinguish individual organisms. The captured animals are counted, a representative sample of them is tagged, and then all animals are released to the same place. After some time, the animals are again caught and the number of animals with a label is counted in the sample (khanacademy.org, 2019).
The population size was estimated by using the following two formulas: