Caving expeditions Negros Oriental, Philippines 1989 and 1992

In 1989 and 1992 I joined two caving expeditions (as a photographer) to the island of Negros in the Philippines. During both expeditions a total of 27 km of caves were mapped in the province Negros Oriental between 1989-1993. From these explorations two expeditionreports were made (you can download these reports at speleo.nl heading expeditions). Negros is the third largest island of the Philippines, which is 200km long and between 40 and 80km wide. Vulcanos north and south alternate with limestone plateaus and canyons. In 1989: Our base-camp was located in the village of Paniabonan (Mabinay) around 35km inland, on a plain some 180m above sea level. During the explorations in the mountains a smaller camp was installed 25km north in Carol-an. Best investigated was the plain around Mabinay. During this expedition about 50 caves were explored and 30 caves were mapped (with a total length of 18 km), although it is assumed there are many more. Most caves were shorter than 1000m, with the exception of Cayaso Cave (2222m) and Odloman Cave System (8870m). Many caves ended in syphons, which nearly all dip to the north, and caves are generally richly decorated.

In 1992: A second expedition went to Negros Oriental. Because of our good contacts with DENR (Department Environment and Natural Resources) we got permission to explore the Guihulngan area in the northern parts of Negros Oriental. This area was opening up for foreigners since 1991.Basecamp was set up at the second floor of the office of DENR in Guihulngan. Guihulngan is a municipality with 23 barangays. The expedition explored in the barangay’s Kinayan, Imelda, Tac-Pao, Bino-Bohan and Sandayao. In the mountains the expedition also set up two subcamps in the sitio’s (villages) Nalundan (Tac-Pao) and in Lip-o (Imelda). Under supervision of the military the expeditionteam got permission to explore the mountains. The mountains and karsthills are 500 to 700 meters high. Entrance to the mountain area is from a road in Bolado. The expeditionteam was split up in 3 groups. One group explored the Lip-o area, the second group explored the area around Nalundan and the third group was working In Guihulngan. The teams worked in shifts. Every time when a group in the mountains obtained to much information (5-6 days) the team came to Guihulgan to write everything down and make a map of the explored cave in the computer. Then the team who was in Guihulngan went to the mountains en so on. During six weeks the expeditionteam mapped 11 caves with a total length of more than 9 kilometer.

Mapped Caves Negros Oriental 1989-1993: Odloman Cave 8870m (+82m),Small Mag-Aso 3498 m (+116 m), Cayaso Cave 2222m (+55m), Mag-Aso Cave 1502 m (-40 m), Lag-Asan Cave 1065 m (- 95 m), Mainit Cave 850 m (-37 m), Baliw Cave 769m (-55m), Natiniti-An 1 Cave 772 m (+23 m), Mambayo 1 & 2 Cave 636m(+35m), Tuntunan Cave 580m (-15m), Kemapegues 469m (-5m), Bugwak Bito 416m (-52m), Tajkan Cave 377m (+11m), Kabogan Cave 373m (-57m), Gripo Cave 368 m (-104 m), Toiopan Cave 333m (-51m), Guano Cave 330 m (-45 m), No-Name Cave 320m (+24m), Awayon Langub 296m (-56m), Pandalihan Cave 282m (+25m), Natiniti-An 2 Cave 250 m (-6 m), Ayakan Cave 233m (-30m), Twin Cave 212m (-54m), Bato Cave 169m (-57m), Tacoy Bito 167 m (-36 m), Cangohob Cave 157m (-18m), Mabaliw Cave 145m (-30m), Panligawan Cave 143m (-22m), Carol-An Bito 141m (-88m), Danekop Langub 1 138m (+11m), Danekop Langub II 136m (-22m), Basketball Bito 134 m (-25 m), Tobud III Cave 116m (+14m), Salung Cave 109m (-39m), Bito Bito 87m (-28m), Bino–Bohan Cave 82 m (-4 m), Tobud I Cave 77m (+7m), Tobud II Cave 58m (+4m) and Lulosbon Spring 54 meter (-4m).