Lakes Bito, Mahagnao, and Danao are renowned lakes in Leyte (Fig. 1). Lake Bito has an area of 126 ha and is within the jurisdiction of the town of MacArthur. It is the most exploited lake among the three study sites. About 40 percent of the lake is covered with fish pens and fish cages devoted to the culture of Nile tilapia. The deeper waters covering about 60% of the lake is devoted to open water fishery. Lakes Mahagnao and Danao are both located within declared natural parks. Lake Mahagnao, in Burauen, Leyte covers an area of 15.75 ha (Francisco, et al., 2001). The whole lake area is devoted to open water fishery, aside from being a source of the micro-hydroelectric power that provides electricity to Barangays Lugsungan, Cansiboy, and Mahagnao. Lake Danao in Ormoc City covers an area of 148 ha. The lake supplies water to the cities of Ormoc and Tacloban. The lake is also developed for tourism, with activities like boating, swimming, and hook and line fishing. There is very limited information about these lakes, with prior studies conducted by Montemayor (1985) and Francisco, et al. (2001). The data obtained was part of a preliminary study on the biodiversity of aquatic flora and fauna of these three lakes. The study was conducted in a period of one year to come up with baseline information about the three lakes. Sampling was conducted once a month in each of the three lakes. Depth, percent transparency, pH level, temperature, and dissolved oxygen (DO) were monitored through a longitudinal survey. Depth was measured using a depth gauge, transparency was monitored using a secchi disc; and pH level was determined using a pen-type pH meter (Milwaukee). Temperature and dissolved oxygen were determined using a DO meter (Cyberscan DO 110). Univariate Analysis of Variance and Tukey HSD were the statistical tools used to analyze the data obtained. Results showed that overall mean depth of water ranged between 1.48 m and 1.90 m; 2.61 m and 4.92; and 2.84 m and 4.11 m in Lakes Bito, Mahagnao, and Danao, respectively (Table 1). Overall mean percent transparency were between 52.59% and 68.06 %; 40.35% and 92.37%; and 63.19% and 97.41 % in Lakes Bito, Mahagnao, and Danao, respectively. Overall mean temperature ranged from 24.99°C to 29.74°C; 20.74°C to 27.32°C; and 19.90°C to 25.60°C in Lakes Bito, Mahagnao, and Danao, respectively. Overall mean DO were between 4.04 mg/l and 10.77 mg/l; 5.37 mg/l and 13.28 mg/l; and 4.93 mg/l and 12.84 mg/l in Lakes Bito, Mahagnao, and Danao, respectively. Overall mean pH were between 6.3 and 8.3; 6.2 and 8.4; and 6.0 and 8.8 in Lakes Bito, Mahagnao, and Danao, respectively (Table 1). There were significant differences (P<0.01) in depth, transparency, temperature, and DO among the three lakes during the study period. No significant differences in pH were observed among the three lakes, although monthly fluctuations within each lake was observed.

The Seven Lakes in San Pablo City, Laguna are all volcanic in origin. It spelled out the uniqueness of San Pablo City, influencing its traditions and culture. The seven lakes comprise the following: Sampaloc, Palaqpaquen, Calibato, Mohicap, Pandin, Yambo, and Bunot (Fig. 1). These lakes multiuses include irrigation, domestic, navigation, sustenance fishing, tourism, and aquaculture. With the increasing population in the lakeshore areas and the various uses of the lake, the demand on the lakes as significant resource has led to the deterioration of the water quality. At the same time, the lakes became sinks of waste. The Department of Environmental Science of Ateneo de Manila University developed the Seven Lakes Research Program in response to the urgent need to maintain the sustainability of the lakes uses. It has been coordinating with the local government units and the fisherfolk community and the FARMC for the past five years. The following are the expected outputs of the Department of Environmental Science for the Seven Lakes: 1. Determining Macrophyte Primary Production and Nutrient Availability in Lake Palacpaquen, San Pablo City, Laguna 2. An assessment of the Coliform Contamination in Sampaloc, Calibato and Mohicap Lake Waters and Selected Springs 3. A Comparative Study of the Effectiveness of Commercial and Farmmade feeds on the Growth of Tilapia 4. Nutrient Dispersion Patterns in Drainage and Lake Sediments: A Study of Sourcing for Selected Lakes in San Pablo City, Laguna 5. The Physico-Chemical Characterization of Sediments in Palacpaquen Lake and Adjoining River Systems, San Pablo City, Laguna 6. Assessing the Effects of Anthropogenic Activities to the Hydrology of San Pablo City, Laguna 7. A Geo-physical and Geo-chemical Assessment of Soils Surrounding Selected Lakes in San Pablo City, Laguna 8. Isolation and Characterization of Denitrifying and Phenoldegrading Microorganisms from Sampaloc Morphometry and Sedimentation of Palacpaquen Lake, San Pablo City, Laguna 9. An Assessment of the Phytoplankton and Macrobenthic Organisms as Biological Indicators in Calibato, Mohicap and Sampaloc Lakes 10. An Assessment of the Benthic Community Structure: Implications on the Water Quality of Lake Palacpaquen, San Pablo City, Philippines 11. A Study of the History of Fishery Utilization of Tilapia in Lake Palacpaquen, San Pablo City, Philippines There is also an existing collaboration with the Department of Electrical and Computer Engineering (ECE) of Ateneo de Manila University where using solar powered water pH, temperature and dissolved oxygen meters immersed in the Lake Palacpaquen are monitored and transmitted to the main server. The Department of Environmental Science is in the process of identifying gaps on the researches done in the Seven Lakes and assessing the future directions.