The colonisation of black rats on this island would lead to the certain death of the only French Polynesian population of ‘Ura , or Kuhl’s Lorikeet (Vini kuhlii). It would also affect the Oroma’o, or Rimatara Reed-warbler (Acrocephalus rimatarae), which is endemic to Rimatara.
These birds not only hold heritage significance but can also help supporting a sustainable economic development through an ecotourism activity like birdwatching.
The invasion of the black rat on the Island of Rimatara would have a major impact on coconut plantations. Rats are good climbers and create extensive damage to coconuts. The monitoring of various rat-infested islands showed an average crop loss ranging between 20 to 80%. This loss can increase up to 90% at low altitudes and during the dry season.
As for human health, the black rat is a vector of the leptospirosis bacteria, and a dangerous one at that, since it is not afraid to venture into homes. It’s difficult to differentiate the symptoms of leptospirosis from flu or dengue fever. Leptospirosis is potentially lethal if not prescribed quickly with antibiotics, and it actually kills a few people each year on rat infested islands.