Rattus rattus

Invasive alien species (IASs) on islands have broad impacts across biodiversity, agriculture, economy, health and culture, which tend to be stronger than on continents. Across small-island developing states (SIDSs), although only a small number of IASs are widely distributed, many more, including those with greatest impact, are found on only a small number of islands. Patterns of island invasion are not consistent across SIDS geographic regions, with differences attributable to correlated patterns in island biogeography and human development.

In November 2007 and November 2008, we conducted a bird and mammal survey on Wallis and Futuna. We found two non-native bird species on Wallis: the Common Myna (Acridotheres tristis) and the Chestnut-breasted Munia (Lonchura castaneothorax), and one on Futuna: the Jungle Myna (Acridotheres fuscus). We also recorded Black Rats (Rattus rattus) on Futuna, a recent introduction to this island. The introduction of 3 bird species and Black Rats in the last decade denotes a lack of preventive measures and demonstrates that the issue of invasive species has not received sufficient priority

In November 2007 and November 2008, we conducted a bird and mammal survey on Wallis and Futuna. We found two non-native bird species on Wallis: the Common Myna (Acridotheres tristis) and the Chestnut-breasted Munia (Lonchura castaneothorax), and one on Futuna: the Jungle Myna (Acridotheres fuscus). We also recorded Black Rats (Rattus rattus) on Futuna, a recent introduction to this island. The introduction of 3 bird species and Black Rats in the last decade denotes a lack of preventive measures and demonstrates that the issue of invasive species has not received sufficient priority.

Seabirds are notoriously sensitive to introduced mammalian predators and eradication programs have benefitted seabird populations and their habitats on numerous islands throughout the world. However, less evidence is available from the tropics as to the benefits of rat eradication. Here, we report the seabird recovery and vegetation dynamics on a small coralline island of the tropical western Indian Ocean, eight years after Norway rat (Rattus norvegicus) eradication.

The three most invasive rat species, black or ship rat Rattus rattus, brown or Norway rats, R. norvegicus and Pacific rat, R. exulans have been incrementally introduced to islands as humans have explored the world’s oceans. They have caused serious deleterious effects through predation and competition, and extinction of many species on tropical islands, many of which are biodiversity hotspots. All three rat species are found in virtually all habitat types, including mangrove and arid shrub land.

The eradication of some introduced pests such as rats, stoats and possums in New Zealand seems increasingly feasible with successful action to date in various cities (e.g. Wellington City) and with the government’s national 2050 predator-free goal. Here we specifically detail the potential benefits of urban rat eradication and find these cover a wide range of topics including a potentially reduced risk of infection from at least seven zoonotic diseases (e.g. leptospirosis, toxoplasmosis, trichinellosis, murine typhus; and three enteric diseases).