The line graph delineates the fluctuation in the population percentages across different species of wild bird in the United Kingdom between 1970 and 2004. It is immediately obvious that, there are significant differences in figures between the bird species. The pattern of lines started to show sharp change in the middle years between 1976 and 1979.
The main feature that distinctly described the prevalence of the costal species, there was a sharp soar in the population between 1976 and 1986. In contrast, regarding to the same period of time, farmland wild birds were in a dramatic declining phase. The correspondent indexes to the two species, where 140 and 65 respectively. In addition, the wood land species had recorded a slight change in their population, the index was maintained to a range of 90 to 110 over approximately 30 years.
From the middle of 1980s, the three types displayed a steady-state for the population figures. Whether there were increasing in coastal species as an example or in decreasing as in farmland wild type, the pattern of line remained unchanged apparently. In other words, despite of rising and falling in the bird species, there was insignificant effect on the overall population figures.