Mamauag, Penolio, and Aliño 54 Science Diliman (January-June 2001) 13:1, 54-65 ABSTRACT Preliminary data on the patterns of occurrence of juvenile groupers in the Philippines was examined. Survey questionnaires were randomly distributed to respondents (i.e., fishers and traders of juvenile groupers). Patterns of presence/absence of the juveniles were examined and recruitment and spawning patterns were inferred from survey results. Results showed that patterns of recruitment of juvenile grou- pers in the Philippines varied greatly with each area/region. The large variability in the recruitment patterns precluded a “general pattern”. Upon closer examination, however, some emergent signals were noted, albeit not very strong. Spatio-temporal patterns for recruitment of juvenile groupers seemed to be influ- enced by change in seasons (summer and wet) and monsoons (northeasterlies and southwesterlies). Inferred spawning patterns likewise varied with area/region and an inter-specific variation in spawning behaviour may be possible. Although results are preliminary due to lack of intensive data verification, a more rigorous type of sampling protocol is worth pursuing in the future. The results of this preliminary examination provided insights on the recruitment of the commercially important epinepheline serranids in the Philippines. Key words: groupers, lapu-lapu, fish recruitment, spawning patterns Deriving Recruitment and Spawning Patterns from a Survey of Juvenile Grouper (Pisces: Serranidae) Occurrences in the Philippines Samuel Mamauag 1* , Lutgarda Penolio 2 , & Porfirio Aliño 1 1 Marine Science Institute, University of the Philippines Diliman, Quezon City 1101 2 Bureau of Fisheries and Aquatic Resources Department of Agriculture, Quezon Ave., Quezon City * Present address of corresponding author: International Marinelife Alliance 2268 Sylvina Bldg., Tramo St., Pasay City; Tel. No.: (632) 831-2805 to 06, E-mail: smamauag@imamarinelife.org INTRODUCTION Fish resources are currently being fully-exploited on a global scale (Hilborn & Walters, 1992; Alverson & Larkin, 1992). Increasing evidence of over-exploitation of fish stocks has been documented (e.g., Munro & Williams, 1985; Russ, 1991; Hilborn & Walters, 1992; Alverson & Larkin, 1992) and management schemes are often either lacking or ineffective (Longhurst & Pauly, 1987). Biological information such as stock size, age, growth, mortality, and recruitment provide the building blocks of population dynamics models which are essential to the development of sound management schemes for these exploited resources. * Corresponding author