Tongariki.jpgTe pito o te huena (Rapanui for "naval of the world"), Rapa Nui (Easter Island) is the most remote inhabited place on earth.  The island is famous for its towering statues (called moai; Ahu Tongariki featured above) and the environmental catastrophe that occurred.  The ancient Polynesians arrived to an incredibly fragile and remote island environment, evolved into a complex society and ultimately exhausted most of their natural resources.  As a result, Rapa Nui is often considered as a cautionary tale for planet Earth.  Given humankind’s insatiable desire for material wealth and unchecked population growth, a similar fate awaits our planet unless contemporary societies embrace sustainability and biological conservation.

easter island deforestation.jpgAs with all oceanic islands, Rapa Nui is volcanic in origin.  Three distinct volcanoes (the crater of Rano Kao featured at right), roughly located in each corner of this triangular shaped island, gave rise to its existence in the middle of the South Pacific Ocean.  Slightly more than 100 km2 in size, Rapa Nui is located approximately 3,600 km west of continental Chile and roughly 2,075 km east of the Pitcairn Island Chain. 

The landscape of Rapa Nui looks much different than it did when the ancient Polynesians arrived over 400 years ago.  The lush palm-dominated landscape has been transformed to a grassland punctuated by patches of invasive Eucalyptus trees.  Most native plants no longer exist, and all native terrestrial vertebrates were driven to extinction by man’s hand.  Today, nonnative invasive plants and animals dominate the landscape.

IMGP2093.JPGJut making sure the insect specimen is actually in vial.  With smaller animals (mites, springtails and book lice), one often double-checks the vial to make sure the animal was collected and isn’t still wandering about under foot.

Of the over 400 known insect species known to the island, only about five percent are believed to be either endemic (having evolved on the island and known to occur only there) or are indigenous (having arrived and became established without man’s assistance). 

Our knowledge of Rapa Nui cave biology is quite limited.  Most entomological research over the past 100 years focused on surface ecosystems.  Prior to the work of Jut Wynne and colleagues, only one species was documented as occurring within caves.  Discovered in 2008, a new species of Collembola (or springtail), known from one cave, is believed to be endemic to the island.

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Jut and the 2009 expedition team about to participate in an Umu Tahu.  Led by Lazero Pakarati (at right unearthing our meal), this ceremony is conducted to ask the aku aku (or spirits) for permission to access the caves.  We feasted on chicken (prepared in an earth oven) and some of the best poi on the planet.

On three separate research trips (in 2008, 2009 and 2011), Jut Wynne and colleagues inventoried 11 caves for insects on the Roiho lava flow.  From this work, they identified at least 50 species of insects using caves.  Of these, most represent invasive species, and many have cosmopolitan (global) distributions or are known to occur on other Polynesian islands.

Currently, Jut and colleagues are preparing several scientific papers on this research.  This page will be updated as these papers are published.

centismer.jpgTwo insect species with cosmopolitan distributions identified from Rapa Nui caves. Left: A stone centipede (Lithobius obscurus). This was the most common ground-dwelling predator found within cave entrances. Right: A female pholcid spider (Smeringopus pallidus) with her egg sac. This pholcid was the most common spider found in Rapa Nui caves.