Question: A Study from the Biological Dynamics of Forest fragments Project (BDFFP) considered the number of understory bird species living in different sized forest fragments surrounded by deforested land. This study involved counting the number of bird species in the fragments at the start of the experiment and then over a handful of years afterward. A scaling factor was estimated to determine the time it takes to lose half of the bird species (t50) in the different fragment sizes. Below is a table with the results of the study, organized by the fragment area:

Fragment Area (ha) Bird species richness initial count T50 (yr)

1. Graph the Initial numbers of bird species by fragment area. Do the fragments follow the species-area relationship?

2. Assuming that the species loss is linear over time, use the table to calculate the percentage loss of species per year in the 1-, 10-, and 100-ha fragments. Which fragment has the greatest species loss per year, and which has the least?

3. Now use the percentage loss per year to calculate the number of species in each of the fragment sizes 9 years after the start of the experiment. Graph the number of species by fragment area on the graph you developed for question 1.
Fragment Area (ha) Initial Number of Species Species loss per year % Number of years Number of species after 9 years

4. If you were to draw linear regressions for the species-area data points at the start of the experiment and 9 years after fragmentation, which species-area relationship would have the steepest slope (z)? Explain why.