[Source: Coral Vita]
Rats! These pesky little creatures are starting to take a bad toll on the environment, especially on an island with a large population of rats. According to a research study done by Lancaster University, the invasive rats devour almost everything, including bird eggs and native bird species. The results? The negative impact has gone even further than hurting just the island’s ecosystem – all the way to the coral reefs.
In the islands of Chagos Archipelago, nearby the Indian Ocean, a team of ecologists studied and compared rodent populated island and non-populated rodent island, finding shocking results. The rodentless island turned out to have a much healthier coral reef system because of the help of the native birds’ rich excrement. In addition, rodent populated island had less native birds compared to the rodentless island.
Now some may ask how rats can affect the coral reefs. Turns out there was an indirect relationship. The nitrogen rich excrements from the native birds give nutrients to coral reefs. However, with the rats eating up native birds and its eggs, the bird population has sunk, meaning less nutrients for coral reefs. Coral reefs depend on these nutrients to maintain habitats for marine organisms. There is a relationship with the land animals to the marine ecosystem: from birds to coral reefs to marine animals.
There are several speculations relating that reefs around the non-rodent populated island has healthier reefs because of the nitrogen from the excrements which acts as a fertilizer. This eventually supports the growth of algae, attracting more fishes to graze and help clean dead coral reefs. This cycle helps the growth of coral reefs and the marine population. However, with the rats affecting native bird populations negatively, the marine food chain is being disrupted. Overall the domino effect of the rats takes a huge toll on the ecosystem.
However, coral reefs have been getting damaged for years because of pollution and human activities (bleaching and littering). Studies are still being continued to find a solution to protect coral reefs from crisis. The disruption of the rats may somehow need to be taken control of; but as of now, researchers are seeing that as only one of the many problems affecting the coral reefs negatively.
Lucy Jin, Grade 12
Cypress High School
