Chapter 9- Islands on Dry Land

In Brazil, there is an island in the center of the Amazon known as Reserve 1202. The area, like many others, are all controlled by the Biological Dynamics of Forest Fragments Project or BDFFP. Kolbert goes to Reserve 1202 with Mario Cohn-Haft, an ornithologist. Cohn-Haft noticed a decline in diversity because capture rate and number and variety of birds in fragments dropped harmful for future ecosystems. Kolbert discusses islands of habitat versus real islands and the effects of diversity against isolation. More specifically, for many species a habitat may prove to be inadequate because of insufficient resources needed to survive. But if a lack of suitable environment was the only issue the area should be able to stabilize relatively quick. However, the habitat will “keep on bleeding species” known as relaxation. Relaxation is a random process. The increase in breeding pairs decrease the chances of the species suffering. However, a small population size is most vulnerable to extinction. But how do islands cope with extinction because of population size?

When extinction occurs because of environmental factors, a new population of species will recognize the area. But, on islands it's very difficult for recolonization. Environments that are fragments lead to a decrease in the number of species in the area. Habitat fragments depend on what surrounds the fragment which can lead to new species being able to recognize the are or not. Kolbert mentions how certain species can be vital for the survival of their environment for other organisms. For example, the Eciton burchellii or army ants are like hunters and gatherers consuming huge amounts of prey. Kolbert notes that some birds are obligate ant-followers who rely heavily on the ants and their habits for survival. When extinction occurs time is a key factor. When deforestation takes place two things can occur: an immediate drop of species making it harder for the forest to “relax” or the habitat can be regrown. A decline in land available for forest animals could set off a domino effect resulting in the extinction of other interconnected species. Chapter 9 connects to the theme of earth is one interconnected system. Global warming is harming to biodiversity which can hurt many ecosystems and set off a wave of extinction. Kolbert states, “there’s a dark synergy between fragmentation and global warming, just as there is between global warming and ocean acidification, and between global warming and invasive species, and between invasive species and fragmentation. a species that needs to migrate to keep up with rising temperatures, but is trapped in a forest fragment...isn’t likely to make it.” (189) Deforestation occurs because of human activity like overpopulation, private corporations and other factors which can lead to a spiral of other problems. When other issues ensue like global warming and habitat fragment they are interconnected and affect the organisms that live there which most likely won’t survive.