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The remarkable bird life of the Wakatobi Islands, SE Sulawesi: hidden endemism and threatened populations

Darren O'Connell
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Working on the avifauna of the Wakatobi Islands was an opportunity to follow in the footsteps of some great ornithologists and biogeographers, out to a remote string of islands off South-east Sulawesi, Indonesia. The Wakatobis have always sat in glorious isolation, they’re a coral uplift which formed upon a platform of Australasian origin and have never been connected to mainland Sulawesi. This isolation has meant these islands are home to a unique mix of species, and have been largely understudied.

Until recently, knowledge of the islands’ biodiversity came solely from a brief visit at the beginning of the 20th century by specimen collector Heinrich Kühn. This trip provided some important museum specimens and hinted at a potential hotspot of new species on theses islands, but no subsequent visits were made, and the Wakatobi Islands largely remained a mystery to science. Then in 1999, teams of researchers from Trinity College Dublin, Halu Oleo University and Operation Wallacea, led by my PhD supervisors Prof Nicola Marples and Dr David Kelly, began a series of eight research expeditions which aimed to investigate this potential trove of unique biodiversity. In our recent paper in the Raffles Bulletin of Zoology we summarise 20 years of remarkable work by Prof Marples, Dr Kelly and others, recording 100 bird species for the islands, highlight recently described species, and discuss the threats facing the resident Critically Endangered species. 

Location of the Wakatobi Islands in relation to mainland South-east Sulawesi and its other offshore islands. The inset shows the location of the South-east Sulawesi region within Indonesia and the wider region.

Reading the original paper on Kühn’s work (Hartert 1903) on the Wakatobi Islands in late 1901 and early 1902 is a step back in time to a very different world. This was the tail end of the Victorian era explosion of natural history collections. These historical collections provided the raw material for developing our formal scientific knowledge of the natural world, with Darwin and Wallace’s Theory of Evolution foremost among those. This era of collections was also facilitated by odious colonial systems, and could be viewed as widescale biopiracy, which serves as a good reminder to temper any overabundance of natural history nostalgia.

The paper itself reads like a mish mash of a modern scientific paper and a Victorian era travel novel. The opening section contains Kühn’s complaints about long delays, inexplicable bureaucracy and the local officials he was obliged to bring by the Sultan of Buton, filling the boat with their opium smoke! Kühn seemed to admire the Wakatobi locals, enjoying their belligerent attitude towards their nominal local lords (the Butonese officials). Despite these more literary flourishes the scientific rigour in the paper is strong, with four unique endemic species proposed for the islands and 57 species recorded.

Kühn and Hartert also comment on the unusual patterns of species occurrence in the region with several species on the Wakatobi Islands not being related to nearby populations on Sulawesi, instead several Wakatobi species were found only on widely separated small islands scattered throughout the Wallacea region. This phenomena of small island specialist “supertramp” species, capable of wide dispersal, is unique to the Indo-Pacific, and was only formally described much later by Diamond (1974). However, much of the insight Kühn and Hartert provided was forgotten or discarded, setting the stage for modern investigations.

Prof Nicola Marples and Dr David Kelly in their element, in the field, leading the bird team.

Prof Marples and Dr Kelly’s modern scientific assessment of the avifauna of the Wakatobi Islands have certainly made for an eventful two decades for them. Their expeditions resulted in a nice collection of tropical diseases (malaria and dengue fever for starters!), innumerable hair raising boat crossings and car trips, a couple of dozen research students inspired to be tropical ecologists and some top class science! As part of this research Prof Marples and Dr Kelly have been able to propose that two of the species originally outlined by Kühn and Hartert (the Wakatobi White-eye and Wakatobi Flowerpecker) receive modern recognition as full species. Remarkably our research has also uncovered a novel bird species, completely new to science, the Wangi-wangi White-eye. This new white-eye species is a single island endemic, only found on tiny 155 km2 Wangi-wangi, the northernmost Wakatobi Island. 

In our latest paper we bring the Wakatobi’s bird species checklist up to a beautifully symmetrical 100 species, and also highlight the urgent conservation threats that the island populations face. The Wakatobi Islands are one of the last remaining homes of the Critically Endangered Yellow-crested Cockatoo, and this small remaining population requires urgent conservation action to survive. In addition, the Wangi-wangi White-eye is extremely vulnerable, being found only on a single small island. Cockatoos and white-eyes have been badly hit by the cage bird trade (Harris et al. 2017), so the small population size of these species will make them particularly vulnerable. The Wangi-wangi White-eye was spotted, being traded illegally in bird markets, only months after its description as a species.

Our hope is that by uncovering new species unique to the Wakatobi Islands, and highlighting the urgent conservation action needed, the Wakatobi Islands can be recognised as a BirdLife International Endemic Bird Area, providing further support for conservation action in the region. TCD, Halu Oleo University and Operation Wallacea are determined to continue to work hard to ensure that some of the stunning wild areas of this region remain intact, and its unique species are recognised!

The Wakatobi Islands could be a pretty nice place to do fieldwork!

To find out more read our full Raffles Bulletin of Zoology article here: ‘An assessment of the avifauna of the Wakatobi Islands, South-east Sulawesi’

Reference

O’Connell DP, Kelly DJ, Kelly SBA, Karya A, Analuddin K, Marples NM, Rheindt FE and Martin TE (2020) An assessment of the avifauna of the Wakatobi Islands, South-east Sulawesi, Indonesia: species recorded and taxonomic considerations. Raffles Bulletin of Zoology, 68: 574–587.

Acknowledgements
Thanks to TCD, Halu Oleo University and Operation Wallacea for facilitating, planning and providing logistical support for this research. A big thanks to Kementerian Riset Teknologi Dan Pendidikan Tinggi (RISTEKDIKTI) for providing the necessary permits and approvals for this study. We thank all the volunteers that assisted with each of our expeditions, including Sean Glynn, Rebecca Graham, Katie Byrne, Rachel Ud-din, Patrick Boyce, Heather Cuddy, Sadhbh Murphy, Susan Doyle, Katie Boyle, Samuel O’Hara,  Deirdre McClean, Katherine Elsom, Emma Hall, Louise Rome, Julia Lubbock, Samuel Jones, Keith  McMahon, Anna Lindemann, Louis Kitchen, Ariana Mouradijan, Larisa Gokool, Henry Ali Singer, Clodagh Dooley, Melanie Sheridan, David Duffy, Rachel O’Sullivan, Niamh McKeon, Martin Meads, Veronica French, Jack Budworth, Richard Randall, Kirsten Purcell, Mark Catterall, Ben Phalan, and Fabrice Tortey. We also thank Joseph Monkhouse and Silviu Petrovan for contributing several photographs to our image library, and James Eaton and Anna Reuleaux for contributing their knowledge about important locations for key Wakatobi Islands bird populations. Photo credits © Nicola Marples, David Kelly and Seán Kelly.

Other posts from the Sulawesi Birds project:

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