Reef Decline as a Result of Climate Change?

EarthzineOriginal, St. George's School, St. George's School 2013 VPS

Cropped image from the reef decline poster. Credit: St. George's School

* This project was conducted by high school-aged students at St. George’s School in BogotÌÁ, Colombia, as part of a 2013 literature review project on ecosystems.

Research question: How will the increasing sea surface temperature in the Great Barrier Reef in Australia affect the symbiotic relation between the zooxanthallae algae and the coral?

Abstract: This project will monitor changes in climate and other environmental factors with the help of satellites. Based on these images, which show alterations in the sea surface temperature and the concentration of chlorophyll, we will be able to determine the areas that are at risk of coral bleaching.

The Great Barrier Reef in Australia is a large coral reef system that is located in the northeast portion of country. Due to its size, it is one of the most biodiverse ecosystems, and is home to many aquatic food webs. In order for coral to be a primary source of food and shelter, it is fundamental that there is a healthy interaction between zooxanthellae and coral.

The holding agent in the coral reef ecosystem is the coral — a colonial animal that develops a calcareous skeleton. This skeleton and distribution of coral colonies form a natural barrier between the open sea and the coral reef. The survival of coral depends on its symbiotic relationship with the zooxanthellae algae living within its tissue. The two have a mutualistic relationship, since the unicellular algae gets its food and energy from the coral, allowing it to photosynthesize and therefore protect the coral. Unfortunately, during the past 10 years, global warming has made the interaction between these two agents much more difficult. A rise in sea temperatures has caused the coral to expel the zooxanthellae, resulting in a process known as coral bleaching. This kills the coral and the extinction of this agent means leaving large numbers of animals without a habitat, food source or protection.

Team members:

Paula Aponte

Juan Felipe Ariza

Jennifer Cianci

Carlos Losada

Julian Molina

Nicolas Valencia