Where have all the pests on Auckland Island gone?
Life on the Auckland Islands is hard. Just ask the settlers of Hardwicke who in 1849 were part of the shortest lived British settlement ever – 2 years and 9 months. The Maori only lasted 10 more years themselves. But what about the mammals they brought with them? Upon the islands ‘discovery’ in 1806 pigs were immediately released within a year. Mice and cats were recorded as present by 1820 but in all likelihood had been introduced earlier by secretive sealing camps well before the islands official discovery.
Compared to my National Geographic funded research mission to Antipodes Island two years ago, I can immediately notice the stark difference on the main Auckland Island. Most obvious is the complete absence of procellariiformes (tube-nosed seabirds): albatross and petrels. Pigs and cats have hunted out almost every last nest and eaten the egg, chick or sometimes even adult. The chatter of their bird calls is silent. Pigs have also rooted up every edible plant on the island, particularly including the delicious megaherbs. Luckily, nearby Adams Island was saved from this fate, maintaining the crucial seabird-ecosystem link. A short-lived farming attempt on Adams Island also failed in the harsh climate, and in part because the captain was found illegally poaching seals and so lost the lease. Today, all that remains of Hardwicke is a few bricks on the ground, and its cemetery. Ironically Olearia tree daisies, themselves possibly an invader, are now colonising the site.