VOICES Ideas and Insight From Explorers
Last week I bore witness to the re-wilding of an entire island ecosystem. Invasive mammalian predators were eradicated from Ahuahu (Great Mercury Island) in 2014, and the original predators and keystone species are now returning naturally.
Invasive alien species are now found on every corner of the planet and rank higher than climate change as a current threat to endangered species. So then why, despite all the scientific evidence of negative impacts from invasive species, would people be resistant to taking action against them?
Brown rats are found throughout the world, on its continents and islands, affecting human health and biodiversity, but where did they originally come from? Researchers this month sought to answer that question when they released a global phylogeography of brown rats from cities and islands around the world.
On Tetiaroa Marlon Brando wanted to “to maintain the natural beauty of the atoll setting” and as our expedition draws to a close we too are marvelling at the natural marine and terrestrial beauty of the atoll.
The Polynesian rat is distributed throughout the Pacific Ocean and is found on most islands. Early European naturalists thought that because the rat was already present it must be native to each island.
Ants are one of the best hitchhikers in the world. This is so true that in the Pacific, it’s hard to unravel whether the ants on even remote motu are native or ancient introductions with original voyagers.
Today we embarked for Tetiaroa with a two hour boat trip from Moorea. As we arrived at Tetiaroa we were fortunate enough to see humpback whales and spinner dolphins greeting us.
Seabirds have incredibly high site fidelity, which means they typically return to the same breeding colony, often where they were born, time and time again. But at the same time they are also amazingly long-distance dispersers to colonise the remotest islands of the world. I was reminded of this paradox this evening barely a few…
As we travelled around the globe humans transported our favourite mammals with us. Either inadvertently such as rats, or intentionally such as cats. These species introductions have gone on to have unrivalled impacts.
The International Union for Conservation of Nature (IUCN) holds a congress every four years and this year it was in the island archipelago of Hawai‘i. Concluding today the congress adopted ‘The Hawaiʻi Commitments’.
Biological invasions can happen quickly and the best response is a rapidly confirmed eradication. Models combining data on the population dynamics of the invasive species with a given level of monitoring effort allow managers to quantify the probability that eradication has successfully been achieved.
This week the second Island Biology conference is taking place in the Azores Islands of Portugal. Its hard to believe its already been two years since the first one in Hawaii.
Antipodes Island is one step closer to being mouse-free after the first bait-drop across the entire island was completed in record time. Department of Conservation staff arrived on the island on 27th May and the first drop was completed by 29th June.
The science of pest control includes developing and testing new tools. Today we deployed self-resetting traps on Goat Island to test their efficiency at keeping rats from perpetually reinvading the island.
Ants are often an unwelcome pest species, particularly on islands, and so its great news this week that one of the world’s worst invasive ant species – the Argentine ant, has been successfully eradicated from Tiritiri Island.