Eye in the Sky: Google Earth used to monitor animal behaviour
Google Earth is a popular free programme that provides satellite imagery and aerial photography of the entire Earth's surface. These free, detailed satellite images are a treasure trove for scientists of all disciplines.
The beauty of Google Earth for scientists is that animal behaviour which leaves a footprint on the landscape can be observed remotely. This makes the research much cheaper and also offers an additional perspective to the one that scientists get from on the ground research.
Until now, scientists have mainly used Google Earth to conduct research on terrestrial sites. Now, in a study published in Scientific Reports, scientists have used Google Earth to research animal behaviour in shallow coral reef habitats.
Dr Madin of the University of Technology, Sydney, led a team of researchers using Google Earth to monitor patch coral reefs around Heron Island, an area of the Great Barrier Reef. Patch coral reefs are small, isolated outcrops of coral, often seen surrounded by 'grazing halos'.
These grazing halos were thought to be made by herbivorous urchins and fish, which feed on seaweed and graze the area down to the substrate. Grazing halos were observed in reefs around Heron Island using Google Earth images. The researchers then visited the reefs and confirmed that the halos were formed by herbivores marine species. Herbivores use coral reefs for shelter, but are forced to venture out to feed. Fear of predators keeps the herbivorous fish and urchins from going too far in search of food, creating a grazing halo around the coral reef. Astonishingly, the collective foraging behaviour of small herbivores is creating patterns in vegetation that are visible from space.
These findings demonstrate that Google Earth can be used to rapidly and cheaply monitor animal behaviour in protected areas, both in terrestrial and aquatic habitats. One use for Google Earth is in assessing the indirect effects of removing or reintroducing predators.
In addition, remotely monitoring predator-prey interactions using Google Earth can indicate the efficacy of protection afforded by national parks and marine reserves. The results of this study show that the use of Google Earth in conservation initiatives has huge potential.
Top Image Credit: © 2011 Nature Publishing Group