Humans won’t be the only ones affected if anthropogenic climate change continues at current rates. Although human industries like agriculture and transportation are largely responsible for increased greenhouse gas emissions, all species on earth will be subjected to the effects of global warming. We must consider the loss of biodiversity that will occur as a result of sea level rise, intensified droughts, and new weather patterns. We stand to lose keystone species like African elephants and sensitive indicator species like sea turtles. We also stand to lose the important ecosystem services that these species provide.
Although there once were millions of elephants roaming the African continent, the total population is now estimated at 470,000 to 690,000. Elephants have been targeted for decades by poachers, because of their valuable ivory tusks. Between 2007 and 2008, the number of elephants poached in Kenya alone jumped from 47 to 98. Their reduced numbers make them more susceptible to threats, such as further poaching and climate change. As a keystone species, elephants have major impacts on their environments. They make clearings by uprooting trees and shrubs; without these massive herbivores, the savanna would be forested. They also disperse more seeds than any other species in Africa. With this in mind, elephants may have the ability to actually mitigate climate change, by ensuring the growth of new trees and carbon sequestration. Rhinos and gorillas are also keystone species in Africa, and both are subject to the effects of global warming. Protecting these species also protects habitats; without them, fewer seeds would be spread and there would be much less plant life. Elephants are especially valuable for habitat maintenance, as they both sow seeds and uproot excessive vegetation.
Sea turtles are indicator species because their presence means that an ecosystem is relatively healthy; these species are especially sensitive to environmental degradation, habitat destruction, and pollution. They are important indicators of environmental quality and allow humans to monitor changes in biodiversity and habitat. Sea turtles—which are already threatened by fishing nets, beachfront development, and poaching—are highly susceptible to global warming. The reefs they feed on are dying because of increased ocean temperatures and the beaches where they lay their eggs are being washed away as sea levels rise. These 150 million year old creatures are also faced with another climate related obstacle: A slight increase in temperature can lead to all-female turtle broods! If the sand around a turtle nest reaches 86 degrees F, there will be more female turtles than males. At 89.6 degrees, all of the eggs will hatch female young. If global warming isn’t reduced, these ancient aquatic reptiles may face extinction.
While sea turtles are helpful indicators of environmental quality, a more unexpected, less vulnerable species may be able to provide unique insight into climate change. Although the melting icebergs of Antarctica are at the center of global warming, only 1% of this frozen continent is routinely monitored. Elephant seals are one of the few species that thrives in this inhospitable climate and humans have found a way to use these mammals in field research. The Norwegian Polar Institute captured twenty bull seals and affixed small instruments to their backs, which use GPS to track water temperature, salinity, and depth. Since these seals swim to depths of 1000 feet in search of squid, they explore underwater Arctic terrain that is far from human reach. Researchers hope that tracking elephant seals will allow them to measure the rate and distribution of ice melting and ocean warming.
Photo credit: Ben Alman