Przydatność danych z wyszukiwarki internetowej do analizy intensywności inwazji biologicznej na przykładzie szopa pracza

Biological invasions are one of the most important problems of nature conservation, which affect several branches of forestry and game management. In case of recent invasions, there is a problem with assessment of invasion intensity due to insufficient quantity of data. In Poland, eight of 31 game species are alien and three small predators are serious threat to biological diversity. The most recent of them is raccoon (Procyon lotor L.). Similarly to studies about rodents and flu, we tested potential of Google search engine to assess whether it may be used as a proxy for species abundance, by downloading search index of phrase 'szop pracz' (i.e. raccoon). We decomposed time series of search intensity in weak intervals into trend, seasonal and remainder, and identified sources of variability within these elements. We also proved, that this time series may be modeled using four moving average model, according to ARIMA technique. Seasonal element was connected with species biology – raccoon was recorded less frequently in winter, due to its lower activity in this time. Remainder was connected with entertainment and law regulation news in most popular websites, which resulted the peak of search index in 2009, when there was a change in length of hunting season for raccoon. Moreover, we proved that annual sums of search indices were positively correlated with hunting gain of raccoon (p<0.05; R²=0.34), thus studied time series is connected with biological phenomena of raccoon invasion. Our results show that search engine queries may be useful in predicting and reconstruction of biological invasions.