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Discovering our diversity
Since its publication earlier this month, the book Contributions to Biodiversity Exploration and Research in Sri Lanka has hit the headlines, its results being carried by all major news syndicates, helping to place Sri Lanka’s threatened biodiversity in the international limelight. The 21 papers presented in this volume announce a ‘quantum leap’ in knowledge of Sri Lanka’s biological diversity: a new mouse deer, 35 new frogs, 7 new lizards, 50 new snails, 16 new crabs... and the list goes on. But not all news is good news, as Dr. Sarath Kotagama, the well-known ornithologist who is also Professor of Environmental Science at the University of Colombo and Chairman of the National Experts Committee on Biodiversity, explains.

Ever since the shortened pseudo-cognate “biodiversity” for “biological diversity” entered the English vocabulary, the numbers of animals and plants found in Sri Lanka (and elsewhere) have become of great interest to laymen and scientists alike. It is now widely recognized that without comprehensive inventories of biodiversity, effective conservation is near impossible. This has even been recognized in the UN’s 2005 Millennium Ecosystem Assessment Synthesis Report which identified the lack of a “complete inventory of species and limited information on the actual distributions of many important plant and animal species” as one of the “important uncertainties hindering decision-making” in biodiversity conservation.

The numbers of species in many groups of animals in Sri Lanka are still in doubt. While birds and larger mammals are relatively well known, diversity in many groups of even vertebrates is still poorly understood. The country’s wealth of amphibians, lizards and snakes are yet to be fully explored, discovered and documented, and no one has even mentioned the almost total lack of knowledge of most invertebrate animals. Yet, up to now, little such exploration has taken place. The new discoveries announced in the 21 papers presented in Contributions to Biodiversity Exploration and Research in Sri Lanka, published earlier this month, show that at last this trend is changing.
Sri Lanka’s biodiversity inventory, especially with respect to the larger and more obvious groups such as mammals, was considered almost complete in the 1960s and 1970s.

The description, identification, nomenclature (giving names) and classification of species (taxonomy), was a neglected science in every academic institution, as more and more people thought, “the task of discovering, describing and naming species has largely been done.” While teaching and researching in taxonomy dwindled, the number of species in each animal group was assumed to be that assessed by early 20th-century scientists. For Sri Lanka, it was mostly foreign scientists who made these assessments, because science was then accessible mainly to expatriates. Specimens (types), being the basis for zoological identifications, were collected and lodged in numerous museums both abroad and in Colombo. Estimates of the country’s biological diversity remained fairly static thereafter, until the early 1990s. Exploration had largely ceased.

Karu
In the early 1980s, my interest in taxonomy was kindled by the late P. B. Karunaratne, who joined us in many field studies. Given the task of documenting the species present in the Accelerated Mahaweli Project Area, we found Karu to be an encyclopaedia of information. Having retired as the Assistant Curator in Entomology at the National Museum, Karu had an uncanny ability to identify species. It quickly became an interesting exercise for us to learn to put names to what we were seeing in the field. Soon we were realizing that there were more species without names (i.e., species “new to science”) than those that had been formally described and named by scientists. Sri Lanka’s biodiversity inventory was far from complete.

I will never forget the day we set out to Aruwakkalu to identify frogs with the Rev. Pinto and Lalith Jayawickrema. As we reached our destination there was a shower of rain and soon the whole area became an orchestra of amphibian sounds. Armed with big “poly bags” we set out in the night to make a collection. We bagged a considerable number of different species of frogs and toads of various shapes and sizes. Being tired, we secured the bag and went to sleep looking forward for an exciting morning of species identification. The morning, however, was a total disappointment. During the night the frogs had escaped and we had only an empty bag to greet us. As a consequence, the list of species for Aruwakkalu still remains uncharted.

Our desire to secure the future of the Sinharaja rainforest in the late 1970s necessitated the compilation of biodiversity inventories. The George Rajapakse Committee (1976) had concluded that “there was not enough scientific evidence to prove the numerous claims of uniqueness of the Sinharaja Forest”. Work on the species composition of plants was already ongoing, and with assistance from the Smithsonian Institute, March for Conservation initiated a research programme in Sinharaja, to document the uniqueness of its fauna. After four years of work we were able to compile a preliminary list, which we now know influenced the basis for its World Heritage Site designation. The inventory of species thus became a very important factor in Sri Lanka’s conservation-planning process and prestige.

Early days
But these species numbers were based on the literature available at the time: we now know that they were gross under-estimates. For instance, the amphibians were identified using the keys provided by Parakrama Kirtisinghe in his 1957 book, Amphibians of Ceylon. Together with an addition made by Bogert & Senanayake in 1966, the number of amphibians as at 1981 totalled 39 species. The tally for (western) Sinharaja stood at only 20. We did suspect that many “new species” were present, but could not identify them as there was no competent amphibian taxonomist in the country.

The renewed interest in biological diversity through the popularization of it as “biodiversity”, rekindled the dying science of taxonomy. This was further supported by the new trend in using DNA to identify species. Novel techniques involving DNA sequencing gave an impetus to the re-examination of many known groups of organism with surprising new discoveries. It is nice to see that all these techniques and more have been used to make the discoveries described in this book.

Anti-Science
This interest was however, was not without obstacles and problems. The increased interest in “biodiversity” also enhanced the sense of “protection” among the growing numbers of “conservationists”, some of whom thought the scientists were out to make money from biodiversity. While lauding the “richness” and high “endemicity” of species in the country, the critics denigrated biologists who were making the scientific collections that are essential for taxonomy. Many non-scientists did not understand why such collections are necessary, and failed to realise that the scientists themselves were doing this only to help conserve the species. They did not understand that without scientific data and sound taxonomy conservation is impossible.

Biodiversity Hotspots
In the late 1990s, the concept of global biodiversity hotspots too, became established. Here, the idea was to act fast and decisively to prevent areas containing “less than 70% of their original natural habitat, and at least 0.5% (i.e. about 1,500) of the world’s plant species” from further destruction. The recognition of ‘hotspots’ therefore has both good and bad connotations, meaning that we have a lot of biodiversity but have not cared for it very well.
Sri Lanka’s South Western region along with the Western Ghats of India was recognized as one of the world’s 21 hotspots in the first assessment of 1998 (34 hotspots are now recognized globally). Sri Lanka by itself, with only about 1,000 endemic plant species, does not qualify to be a ‘hotspot’ on its own. India’s Western Ghats and Sri Lanka together have about 3,000 endemic plant species and so jointly qualify as a hotspot.

The enhanced interest in biodiversity also set the stage to lay new emphasis on the smaller, lesser known animals in the country. The large fauna, such as elephants, leopards and deer were very well known and looked after by the numerous conservation plans. However, the smaller fauna and flora received little attention until the 1990s.

A problem faced by the conservation planners in Sri Lanka is that they often cannot know what to conserve, except for large animals, which are obviously threatened (e.g. the elephant). In the case of many groups of smaller animals such as frogs, a lack of exploration has meant that we have only a vague idea of how many species there are, what their habitats are, and whether or not they are threatened. Without this information, it is impossible to implement conservation measures. After all, if you don’t know that a species exists, or where it lives, how can you conserve it?

Highest standard
Against this historical background, it is good to see the body of research that has been published in the volume titled Advances in Biodiversity Exploration and Research in Sri Lanka, a collection of 21 papers presented in a special supplement of the Raffles Bulletin of Zoology. These papers provide a great deal of new information on Sri Lanka’s biodiversity, ranging from the importance of mountaintop forest fragments to the description of almost 50 new species of vertebrate animals. Much of this research is the work of the Wildlife Heritage Trust (WHT), which is well known also as a biodiversity research foundation and a major publisher of biodiversity-related books on Sri Lanka. The papers are clearly the culmination of years of field work on the part of several local biodiversity researchers, supplemented in some cases by foreign expertise.

Some may be critical of the fact that the publication was done abroad and not in Sri Lanka. However, with such a large number of new species being described, scientific credibility was obviously a factor the project’s leader, WHT’s managing trustee Rohan Pethiyagoda (who is co-editor of the volume) was concerned about. Rohan explained to me that the decision to publish these papers in Singapore and not in Sri Lanka was made because he wanted the highest standard of peer review and also wanted this work to be disseminated as widely as possible internationally. The publisher (Singapore’s Raffles Museum of Biodiversity Research), has made a limited amount of copies available for sale in Sri Lanka at a subsidized price, so as to make it widely accessible to the general public and local conservationists.

Serendipity
Following on their earlier announcements published in two key papers in the international journal Science in 2002 and 2004, Rohan Pethiyagoda, Kelum Manamendra-Arachchi and Madhava Meegaskumbura of WHT describe 35 new species of frogs, all of them endemic to Sri Lanka (i.e. found nowhere else in the world). Thirty-five species is almost 1% of the world total of frog species, and this is a remarkable finding in Sri Lanka. The authors are now involved in describing the next 35 species, for there are more that have been discovered, but not yet described in detail.

This detailed study, however, has brought to light the sad realization that we have in the last few decades been responsible for the extinction of 19 known species of Sri Lankan frogs. Based on a global survey made for the IUCN’s Red List in 2004, this represents more than half of the 34 amphibian species that have become extinct worldwide, showing that urgent conservation measures are needed to save the remaining threatened species in Sri Lanka. Amongst the 65 species of tree frogs now known from Sri Lanka, the researchers have found that 17 species are extinct, 7 critically endangered and 19 endangered, showing that further extinctions may be imminent.

The findings presented in Contributions to Biodiversity Exploration and Research in Sri Lanka add greatly to our knowledge of Sri Lankan biodiversity, and help us to formulate conservation plans. For example, several papers underline the need to conserve hilltop forest “isolates” in the wet zone, especially areas such as Morningside, at which almost 20 new species of frogs, lizards and crabs have been recorded. It was only two years ago that an attempt by a powerful minister of the former government to alienate a large part of Morningside for tea cultivation was stopped after the clearing of land was reported to the Central Environmental Authority by researchers from the Wildlife Heritage Trust who were doing field work there at the time. The results of this new research make a powerful case for Morningside to be annexed to the Sinharaja World Heritage Site.

I hope that these exciting results will lead to a new phase of exploration and research on the biodiversity of Sri Lanka, providing data for conservation planning. Which species are in imminent danger of extinction and need recovery programmes? Which habitats are essential for the survival of biodiversity? How will we conserve species that live outside the protected area network? How will we manage the invasion of protected areas by alien species? What will the impacts of climate change be on Sri Lanka’s biodiversity, and how will we mitigate them? All these, and so many other questions can be answered only through more research. A good start has been made, and it is now necessary to keep up the good work, with universities, government agencies, NGOs and private individuals joining hands for a common cause.

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