Invasive predators and islands conservation

Invasive predators have contributed to close to 60% of extinctions of birds, mammals, and reptiles.

13 October 2016, Sara Kaiser

Published on Island Conservation website

That is reported in a new study published in Proceedings of the National Academy of Sciences :

Invasive predators and global biodiversity loss – PNAS 2016 113 (40) 11261–11265; published ahead of print September 16, 2016,

Authors :

• Tim S. Doherty,
• Alistair S. Glen,
• Dale G. Nimmo,
• Euan G. Ritchie,
• and Chris R. Dickman

The International Union for the Conservation of Nature classified 596 species listed as Vulnerable, Endangered, or Critically Endangered due to invasive species.

The actual number is believed to be higher and the study indicates that the threat of invasive species to biodiversity generally was previously underestimated.

The research also revealed that island species with high evolutionary distinctiveness are most vulnerable to invasive species impacts.

81% of species threatened by invasive predators are found only on islands.

Feral cats and rats combined threaten 850 species.

Invasive mice are also eroding ecological health on islands.

Though small, invasive mice have been documented eating seabird chicks alive while the mother is away searching for food.

Feral dogs, pigs, Indian mongooses, red foxes, and stoats are also highly destructive invasive species.

Once introduced to an environment, these large invasives can do a lot of damage in very little time.

Invasive species threaten not only individual animals but also entire ecosystems.

The presence of invasive species can drastically alter interspecies interactions–upsetting predator-prey balances, vegetation composition, and nutrient cycles.