The graph shows a species of finch native to Eastern Europe.
1400
The finch population reached its carrying capacity for the
ecosystem between 1975 and 1976 after which time rapid
deforestation and logging took place. Starting in 1979 the local
people became concerned that the native finch population had
declined drastically and began replanting mature trees in the area at
which point the finch population then grew to levels seen in
1975-1976. Which of the following explanations is the most credible
given the changes in the finch population?
Population size
1000
600
200
1975 1976
Ye
A. The trees were not acting as sufficient producers in the
ecosystem
В. The finches encountered a biotic factor like a disease that
cause their population to decline.
С. The trees were unable to continue their normal growth due to
the over abundance of finches.
D. The trees were acting as a limiting factor that was preventing
the finch population from growing.