- A team of ecologists examined the impacts that invasive rats on tropical islands have on coral reef ecosystems.
- Because rats eat seabird eggs and young, they can decimate seabird populations.
- With fewer seabirds depositing their guano on islands, coral reef ecosystems near rat-infested islands can’t support as much life.
- The findings suggest that eradicating rats from tropical islands could be a straightforward way of bolstering the health of coral reefs.
TOULOUSE, France — Rats exact a punishing toll on island seabird colonies, decimating their numbers as they eat the birds’ eggs and young. Research has shown that fewer birds, and fewer bird droppings, mean that ecosystems on these islands don’t have the same diversity and quantity of life. But until now, our understanding of the impact that rats have has stopped at the island’s edge.
“What people haven’t really captured is how that then affects adjacent marine ecosystems,” said Nick Graham, a marine ecologist at Lancaster University in the U.K.
Graham is the lead author of a study published July 11 in the journal Nature, in which he and his colleagues demonstrate that coral reefs next to rat-infested islands aren’t as healthy as reefs near rat-free islands. He presented the team’s research on July 10 at the European Open Science Forum 2018 (ESOF18) in Toulouse, France.
“These rats are having a knock-on effect to the adjacent coral reef system,” Graham said, “and that’s never been shown before.”