Environment 

The tiny island of Polillo is virtually unknown amongst the 7000 others that compose the fringing archipelago of the Philippines. However the ‘island of plenty’, as it was first named by 7^th century Chinese sailors, has much more to it than first meets the eye. A long way removed from the hustle and bustle of life in Britain, with barely any roads (or resemblance to roads), no cars, and only lush green coconut trees for as far as the eye can see. No one would suspect the treasures hidden deep in the island's remnant forest.
        The Philippines is renowned for its wealth of biological diversity. Its abundant wildlife includes many species found nowhere else in the world. Few though are aware that the tropical rainforest harboring these rarities is disappearing at an incredible rate. Polillo, like much of the Philippines, was densely forested until after the Second World War. Subsequently a staggering 97% of the nation’s forest has been destroyed. So dense was the original forest on Polillo that it took many teams of loggers a full 25 years to strip the island of wood, which was later exported to Japan. Today less than 3 square kilometers of primary forest remains on Polillo. This tiny oasis is nested among vast tracts of coconut trees that provide virtually the only income for the islands 50,000 or so inhabitants.
        An intrepid group of young and relatively inexperienced students from the United Kingdom departed for Polillo in 1999 with ambitious if not naïve aims of discovering unknown species and completing detailed ecological surveys on the island. Fortunately the expertise of Filipino counterparts brought their objectives closer to reality. No one had documented the fauna of Polillo Island since the extensive collecting days of the exploring American biologist Edward H. Taylor in the early 1920s. At the time Taylor had recorded species unique to the island's forest, but with the rapidly ensuing deforestation, it was possible that many of these would already be gone, for good.
        With this in mind, the students from Oxford University and the University of the Philippines in Los Baños, agreed on a collaborative project, and arranged to spend three months on Polillo, armed with Taylor’s historic records in an attempt to complete biological surveys within Polillo’s watershed reserve. Fortunately Enteng, Polillo’s recently appointed wildlife warden, took the team under his wing, together with several other islanders that have intimate knowledge of it’s forest. Camped a 10-minute walk away from the tiny Sibulan Watershed Reserve, all 2.8 square kilometers of it, the team brainstormed a plan of action, listing rotas and devising methodologies for studying such diverse groups from bats to trees, contemplating the past records and possible methodologies.

The tiny, white Polillo forest frog, platymantis polillenlis

One particular species of interest to the project was the Polillo forest frog. This miniature island endemic presumed by most researchers to be extinct had not been seen since 1922, and possibly remained preserved only in a few dusty pickling jars from Taylor’s first species description. Certainly these thoughts occurred to me while trudging through thick mud, night after night, for weeks on end, searching meticulously for hours at a time. The expedition team had become closely familiar with the many different types of frog found in Polillo's forest, having spotted thousands of individuals in torchlight beams, and always to an accompanying chorus of singing amphibians. So when, nearing the end of the three months, out of the green, a truly unrecognizable, miniature beastie was spotted sitting inconspicuously on a leaf, it was with some excitement muffled with caution that we caught the animal. Yes, indeed, this little white frog was the previously presumed extinct Polillo forest frog that had evaded searchers until that memorable night in the depths of the forest. Even more amazingly during a short excursion to the north of the island only a week later, an unrecognizable chirrup was tracked down by Enteng and it too turned out to be the elusive Polillo forest frog.

The butaan, Gray's monitor lizard, can grow to a length of two meters

        Another great and welcome surprise was our success in the study of Gray’s monitor lizard, an extraordinary and mysterious animal of dinosaur proportions. One of the largest lizards in the world, it was known from only one specimen in the British Museum, and generally considered extinct, between 1845 and 1976, when it was rediscovered by Walter Auffenberg of the Florida State Museum. Its tough, weathered, battle-scarred skin and thick set powerful jaws help affiliate it with its carnivorous cousin the Komodo dragon of Indonesia. However the diet of this animal is uniquely fruit, complemented by snails and crabs, possibly a reason why the Butaan, as it is known locally, has the unenviable reputation for being delicious, its rarity making it a particularly prestigious food.
        When we were first told that the almost mythical Gray’s monitor lizard still survives on Polillo today, we were very skeptical that this huge lizard, reaching a total length of almost 2 metres could still inhabit this island, with so little forest cover still remaining. Described as "shy" by hunters because of its reclusive habits, Auffenberg stated that it would be possible to spend years in the forest without being aware of the animal's presence. However, we were fortunate to have the expertise of skilled ex-hunters, whose ingenious trapping techniques resulted in the capture of a total of nine animals. To each of the lizards we attached rather unconventional tracking devices – cotton reels! -- and then we released them.

The author examines a medium-sized butaan

        In the days that ensued we attempted to follow these trails of thread in an unlikely imitation of Theseus’ escape from the labyrinths of Crete. Often while battling through thick thorny undergrowth losing track of the threads, we discovered instead vast nests of ferociously furious large red ants who rewarded us with multiple savage bites.
        However, quite literally on the trail of the Butaan, we had some exciting finds. Occasionally the lizards left behind exciting gifts: large, fresh, stinking piles of feces often containing large Gnetum seeds, an ancient fruit that existed during the reign of the dinosaurs and had not been previously known as a food of the lizard. Our observations suggest that, between July and September, adult Butaan feed largely on fruit. Most of the fruits eaten occurred not only in the forest remnants but also in cultivated areas. Thus food availability did not appear to explain why the Butaan cannot survive outside the forest. A more likely reason for its limited distribution is likely to be its requirement for very large shelter trees. All the trees used by the lizards during the study had a circumference of at least 90cm, and tended to be tall, emergent trees with lots of shelter in the form of vine thickets. These trees were rare in the forest, and much rarer outside the protected area. Unfortunately they have exactly the same characteristics as the trees which are preferred by loggers, who illegally collect timber with chainsaws. Consequently, the available habitat for this rare and magnificent animal continues to decline.
        From enormous lizards to ones small enough to sit on the palm of your hand, members of the team, taught by our intrepid and quick-handed guides, were soon able to catch a whole variety of small skinks and geckos. Of all colours and patterns imaginable, from mottled browns to the almost flourescent green, yellow and pink skin of the endemic Polillo green gecko, these beautiful, small lizards brightened up the forest floor and bushy vegetation as we scouted the forest. Some team members had the unenviable task of bird-surveying from the first crack of dawn till deep into the night, when the owls could be heard and roosting doves encountered. Though exhausting this was another productive task, as some of the birds recorded such as the Polillo trogon are unique to this small island, and quite different from their nearest relatives on the mainland.

  The trogon  of Polillo

       A colleague of one of the Philippine students passed on an inspirational bat-trapping method, which makes the net undetectable to the microchiropteran bats' highly developed echo location system until they are right within it. Many an expectant evening was spent waiting inside the trap, wading in the streams that make up the network waterways trickling through the Watershed Reserve, ready to entrap any unsuspecting victim (of course all animals were released after they had been measured and photographed). With this revolutionary new trap, the team successfully managed to trap 19 species, adding 11 to the list of bats found on Polillo, having never been caught on the island before.

 The ptenochirus bat of Polillo looks able-bodied and fierce

       What the future holds for the Butaan and other forest-dwelling animals depends almost entirely on whether sufficient forest can be conserved to allow them to survive in sufficient numbers. The problem is not a simple one. The forest timber represents a resource that can be profitably exploited by anyone with access to a saw. Although many recognise that forests are precious in their own right and provide protection from a great number of potential environmental catastrophes, for most people, immediate needs are simply too urgent to allow the luxury of maintaining pristine habitats. For Gray’s monitor lizard, and the multitude of other unique creatures of the Philippines, the likelihood of continued existence depends largely on whether the people sharing its habitat can attain the reasonable standard of living they are entitled to without destroying the last vestiges of their precious heritage.
        So despite initially overambitious aims the Polillo 1999 expedition turned out to be a great success: rediscovering species previously thought extinct, documenting new records of the island's fauna, and gaining an understanding of the ecology of the island and the threats it faces. But the most memorable thing in my mind is the fun that was had by all, a great team full of laughter and jokes, yet desperately hard-working, and we thus felt that leaving Polillo was like leaving home. Which explains why again in 2001 the same team is returning to Polillo, this time armed with posters and tape recordings, in an effort to help Enteng in his effort to publicise more widely the uniqueness of Polillo’s wildlife, and to find what other treasures may exist on Polillo.

Katie Hampson finished her BS course in Biology at Oxford University this year. While still a freshman, she and four other Oxford undergraduates won a British Petroleum Conservation Award for their research proposal on the monitoring and documentation of Polillo's biodiversity. The team stayed several months on the island of Polillo, working with their counterparts from the University of the Philippines in Los Baños. In July this year, the team went back to Polillo and will be staying for a much longer period.