Estimating the number of bird species in INBio Park in the Central Valley of Costa Rica

Costa Rica, famous for its conservation efforts, has recovered a massive amount of forest cover in recent decades. However, remaining problems like urbanization threaten many animals\u27 habitats that depend on forests and tree cover. MacArthur and Wilson put forth the Theory of Island Biogeography, which established the likelihood of species survival based on proximity to the mainland and island size. Using their ideas, a slightly altered theory allows urban environments to replace water and form artificial islands that can roughly follow principles of island biogeography. Species identification observations and a population estimation curve were used to estimate how many species of birds live in INBio Park, a forest patch developed by the National Institute of Biodiversity. 27 distinct bird species were observed, three of which are considered partially forest dependent. 20 to 30 yet unobserved species were estimated to abide in the park based on the rate of decreasing daily new species observed. This indicates that INBio is not large or isolated enough from the city for true forest-dependent species, but it is sufficiently large or partially forest-dependent species not otherwise found in a city. While MacArthur and Wilson\u27s Island Biogeography relates mostly to real islands separated by water, the urban environment is a significant enough barrier for some bird species, and the biogeography theory is relevant. This could be explored further by examining common vs unique species between specific forest patches of various proximities and sizes, and further classification of artificial urban forests with regards to various forest dependencies