The Philippine Agricultural Scientist Vol. 89 No. 1 (March 2006) 97 Algal Bloom Occurrence in Coastal Waters J. P. Peralta et al. THE PHILIPPINE AGRICULTURAL SCIENTIST ISSN 0031-7454 Vol. 89 No. 1, 97-100 March 2006 An Investigation of the Algal Bloom Occurrence in the Coastal Waters of Barangay Kirayan Norte, Miag-ao, Iloilo, Philippines Jose P. Peralta 1* , Soledad S. Garibay 2 , Rose Marie M. Espina 3 , Hon. Jose Rey N. Noble 4 and Angelito N. Nualla 3 1* Institute of Fish Processing Technology, College of Fisheries and Ocean Sciences, University of the Philippines in the Visayas, 5023 Miag-ao, Iloilo, Philippines (Author for correspondence; e-mail: peralta2k2@yahoo.com) 2 Museum of Natural Sciences; Institute of Aquaculture, College of Fisheries and Ocean Sciences, University of the Philippines in the Visayas, Miag-ao, Iloilo, Philippines 3 Miag-ao Municipal Health Office (MMHO), 5023 Miag-ao, Iloilo, Philippines 4 Sanggunian Bayan, Municipality of Miag-ao, Miag-ao, Iloilo, Philippines On March 1, 2005, residents of Barangay Kirayan Norte, Miag-ao, Iloilo complained about the foul smelling sea breeze that was emanating from the shore and that caused difficulty in breathing in children, and problems of sleeping at night, skin irritation and itchiness in adults. The smell of the sea breeze was characterized as seaweedy and ammoniacal, with a tint of decay. Residents attributed these problems to the occurrence of a dense mat of floating algae in the shorelines. The floating marine algae in the coastal area were harvested and later buried in a make- shift pit; the person who did the job subsequently suffered from swelling of the face and other skin irritations. The causative organism was preliminarily identified as Lyngbya majuscula. Proliferation of Lyngbya majuscula may now pose risks to the coastal communities in the near future. It would be best to collect more information about the organism’s occurrence and distribution in order to address and appropriately mitigate future incidents of similar nature. Further monitoring and study of this phenomenon is highly recommended. Key Words: Lyngbya majuscula, harmful algal bloom (HAB), skin irritation, face swelling INTRODUCTION Residents of Barangay Kirayan Norte, Miag-ao, Iloilo com- plained about the foul smell from the sea breeze emanating from the shore on March 1, 2005. They noted that children had problems in breathing, while the adults had difficulty sleeping at night and complained of skin irritation and itchiness. At that time, the wind direction was toward the coast. The coastal residents were experiencing nasal irri- tations, difficulty in breathing, dermal irritations and eye sores. Some families evacuated the area and temporarily resided with relatives elsewhere. The smell of the sea breeze was characterized as seaweedy with a tint of decay. The ammoniacal odor was very pronounced. Barangay Kirayan Norte is located 122 0 15.20’east and 10 0 38.5’ north in the municipality of Miag-ao in Iloilo, one of the provinces of Panay Island, which is part of the Western Visayas region of the Philippines (Fig. 1). Kirayan Norte has a population of 1,500. Residents attributed their problems to the floating al- gae along the shorelines; the algae were observed to be more than usual. The dense mat of marine algae was dark green to blackish in color with hair-like strands. The algae, which were described by the residents as “lumot”, piled up on the shore when carried by the waves. There was also a noticeable thick mat of algae underwater, which extended up to about 100 m away from the shoreline, and up to a depth of about 4.5 m. The floating marine algae in the nearshore were har- vested, and buried in a makeshift pit along the shore. As reported, about two truckloads of algae were harvested on the first day of their occurrence. Those who buried the algae experienced swelling of the face and body irritations. Figure 2 shows Barangay Kirayan Norte’s shoreline with the thick mats of algae. A preliminary investigation was conducted with the formation of an Ad Hoc Response Team by the municipality of Miag-ao. Research Research Research Research Research Note Note Note Note Note