Philippine Journal of Science 140 (2): 195-206, December 2011 ISSN 0031 - 7683 Date Received: 29 Apr 2010 Freshwater Fish Fauna in Watersheds of Mt. Makiling Forest Reserve, Laguna, Philippines Vachel Gay V. Paller1*, Bonifacio V. Labatos Jr.2, Beatriz M. Lontoc2, Olivio E. Matalog2, and Pablo P. Ocampo1,2 1Animal Biology Division, Institute of Biological Sciences, College of Arts and Sciences, University of the Philippines Los Baños 2UPLB Limnological Research Station, College of Arts and Sciences, University of the Philippines Los Baños Survey of freshwater fish fauna was conducted in watersheds of Makiling Forest Reserve (MFR), Laguna, Philippines. These watersheds were Molawin Creek, Dampalit Falls, and Cambantoc River, all in the Province of Laguna, Philippines and directly under the management of Makiling Center for Mountain Ecosystems (MCME), University of the Philippines Los Baños. There were 10 families of fish found in MFR. Two native species, Rock goby (Glossogobius celebius) and Snakehead gudgeon (Giuris margaritacea), were found to be common in all the watersheds of Makiling Forest Reserve. Similarity index of the three watersheds was computed at 72 %. Diversity index of the study areas was 1.12, 1.15, and 0.85 for Dampalit Falls, Molawin Creek, and Cambantoc River, respectively. In terms of species richness, Molawin Creek had twelve species, four of which are native; Dampalit Falls had twelve but with five native and one endemic species; and Cambantoc River had nine with two native species. The study revealed that Makiling Forest Reserve harbors a diverse community of fish. However, diminutive species which are becoming prone to extinction, such as Glossogobius celebius and Hippichthys heptagonus, also found the place as a haven especially in those areas with least human interventions. The study also showed that there was no significant difference in the physico-chemical properties among the three sites. Conservation efforts must focus on protecting these areas to guarantee the continuous existence of these diminutive species which are very important components of our freshwater ecosystems. The survey also updated the list of freshwater fish fauna of Makiling Forest Reserve. Key Words: fish diversity, freshwater fish, Makiling Forest Reserve, similarity INTRODUCTION country’s natural heritage (Vallejo 1986; Ng et al. 1998). The Philippines is a globally important hotspot for Many unique species of freshwater fishes, particularly biological diversity and center for endemism, but much gobies, pipefishes and halfbeaks are known to be restricted of the studies are centered in terrestrial and marine only to isolated lakes and rivers in major islands in the biodiversity (Mallari et al. 2001; Ong et al. 2002). Little Philippines, but their current status in these beleaguered is known about the diversity and status of endemic freshwater habitats is not known (Herre 1953; Butler freshwater fishes which are equally valuable as bio- 2006). Gobies represent the most diverse group among indicators of ecosystem health and an integral part of our the freshwater fishes in the country, with about 16 species known to occur only in the Philippines (Froese and *Corresponding author: [email protected] Pauly 2010; Eschmeyer 2011) that include Gobiopterus 195 Philippine Journal of Science Paller et al.: Freshwater Fish Fauna in Watershed of Vol. 140 No. 2, December 2011 Mt. Makiling Forest Reserve lacustris of Laguna de Bay (Herre 1927), G. stellatus of ecosystems, notwithstanding the economic potentials of Lake Dapao, Lanigay, Polangui, Albay (Herre 1927) and these species in local fisheries – especially in the multi- Mistichthys luzonensis of Lake Buhi in Buhi, Camarines million tropical fish industry (Guerrero 2002; Grist 2007). Sur (Smith 1902). Continued threats from pollution, erosion and introduction of invasive species pose a level of uncertainty on the Taal Lake is the only habitat of the world’s only known survival of these endemic fishes, coupled with the lack of freshwater sardine, Sardinella tawilis (Herre 1927). local concern/education or stable protection (Bagarinao More interestingly, there are four endemic Gulaphallus 2001; Diesmos et al. 2004; Cagauan 2007). species: G. bikolanus (Herre 1926), G. eximius (Herre 1925), G. falcifer (Manacop 1936) and G. mirabilis Development of strategies through habitat protection, (Herre 1925) as well as four Neostethus species of the captive-breeding and local education is vital to the family Phallostethidae: N. ctenophorus (Aurich 1937), N. conservation of these potentially endangered endemic robertsi (Parenti 1989), N. thessa (Aurich 1937) and N. fishes. Consequently, surveys done in other Southeast villadolidi (Herre 1942) that only inhabit the freshwaters Asian countries led to the description of many new of the Philippines. The country also has an endemic rice species, and subsequent surveys on selected lakes and fish, Oryzias luzonensis (Herre and Ablan 1934) from the rivers of the country may reveal similar new discoveries family Adrianichthyidae. There are about sixteen species (Kottelat et al. 1993; Watson & Kottelat 2006). of the family Cyprinidae with species known mostly from Lake Lanao in Mindanao and Lake Manguao in the The Makiling Forest Reserve (MFR) which is under island of Palawan namely, Cyclocheilichthys schoppeae the administration of the University of the Philippines (Cervancia and Kottelat 1997), Puntius amarus (Herre Los Baños - Makiling Center for Mountain Ecosystems 1924), P. bantolanensis (Day 1914), P. cataractae (Fowler (MCME), covering the municipalities of Los Baños, Bay, 1934), P. disa (Herre 1932), P. flavifuscus (Herre 1924), and Calamba in the province of Laguna and Sto. Tomas P. hemictenus (Jordan & Richardson 1908), P. herrei in the province of Batangas. Being a forest reserve under (Fowler 1934), P. katolo (Herre 1924), P. lanaoensis the direct supervision of an academic institution, a number (Herre 1924), P. lindog (Herre 1924), P. manalak (Herre of research works has already been initiated to study its 1924), P. manguaoensis (Day 1914), P. sirang (Herre rich biological diversity, its flora and fauna like mammals, 1932), P. tumba (Herre 1924), and Rasbora philippina reptiles, amphibians, and birds but little attention is given (Günther 1880). on the fishes of MFR. Except for the surveys conducted by Herre in 1927, 1931, 1936-1937, and 1940-1941, There are few species described in the Philippines after which merely listed the freshwater fishes he collected the monumental work done by Herre (1924 and 1927), from Molawin Creek, no studies to date have examined due mainly to the limited surveys conducted in the country the natural fish population of MFR; hence, this study after World War II. The most recently described species was done to record and collect fish samples, determine in the Philippines include the following freshwater fishes: species composition, and diversity to contribute to the Stenogobius kyphosus (Watson 1991), two new species of better understanding of its faunal richness. Stiphodon: olivaceus and surrufus (Watson and Kottelat 1995) from Leyte, Sicyopus cebuensis (Chen and Shao 1998) from the island of Cebu, Stigmatogobius elegans (Larson 2005) from Luzon, Cyclocheilichthys schoppeae MATERIALS AND METHODS (Cervancia and Kottelat 2007) from Palawan and Anguilla Study Sites luzonensis (Watanabe et al. 2009) from Cagayan River. The Makiling Forest Reserve (14° 08' N, 121° 11' E), At least 20 species of endemic non-commercial freshwater which is under the administration of the University of the fishes are known to occur in Southern Luzon, and their Philippines Los Baños - Makiling Center for Mountain possible sustainable use, socio-cultural and eco-tourism Ecosystems (UPLB-MCME) lies approximately within 65 value to local communities have not been tapped km South of Metro Manila covering the municipalities of (Gonzalez 2006; Froese and Pauly 2007). And much Los Baños, Bay, and Calamba in the province of Laguna of the research done on freshwater ecosystems locally and Sto. Tomas in the province of Batangas and has a is focused on commercially important fishes (Samonte total area of 4,244 ha. The MFR is divided into six major et al. 2004); however, the implications presented for watershed zones: Zone 1- Molawin/Maralas Watershed, equally valuable endemic species to ichthyology and Zone 2 – Dampalit Watershed, Zone 3 – Puting Lupa/Tigbi environmental science were apparently overlooked Watershed, Zone 4 – Sipit/Sto. Tomas Watershed, Zone (Santiago et al. 2001). Impending loss of these diminutive 5 – Cambantoc Watershed, and Zone 6- Maitim Watershed but integral components of the aquatic food web may have (Cruz 1992). A total of three major watersheds of Makiling detrimental effects on the natural balance of freshwater Forest Reserve (Figure 1) were studied representing 196 Philippine Journal of Science Paller et al.: Freshwater Fish Fauna in Watershed of Vol. 140 No. 2, December 2011 Mt. Makiling Forest Reserve two rivers and a cataract. Study areas include portion were done during sampling. Seine netting is effective on with primary forest growth, secondary forest growth, banks of lakes and rivers but hard to use in rocky areas. agroforestry areas, near and within human settlements Hand-nets of ‘sinamay’ mesh were also used as traps that are subjected to various human disturbances. Some during low voltage electro-fishing, wherein they were areas have riparian growth, others have none. These three placed at the end of the transect