BACKGROUND: Ports and naval bases play a significant role in understanding marine macrofouling and the associated transport of species across boundaries. Structures on ports and piers become habitats of foulers, whether indigenous or non-indigenous. There is a paucity of literature on species composition of foulers in ports in the Philippines. Naval Base Heracleo Alano in Cavite City, formerly known as Sangley Point, is a potential habitat for non-indigenous species.

METHODS: The study assessed benthic biofoulers at four areas in close proximity at Naval Base Heracleo Alano, Cavite City, using artificial collectors. Fouler collector design was adapted from the North Pacific Marine Sciences
Organization (PICES). Fouler collectors were deployed in 4 sampling points from November 2015 and retrieved in February 2016. Collected fouling organisms were identified using taxonomic keys. Species diversity (H) through Shannon Wiener Index, Species Evenness (H'/H'max), and Simpson's Index were determined.

RESULTS AND DISCUSSION: A total of 6203 organisms belonging to 20 families was collected. Common macrofoulers were bivalves, polychaetes, decapods, amphipods, and barnacles. Shannon-Wiener index values as well as species evenness were relatively consistent. Values of the Simpson's index indicated the presence of dominant species, Balanus sp. The macrofouling community contained 7 non-indigenous species, namely, Mytella charruana, Brachidontes, Mytilopsis sallei, Hydroides, Stylochus, Sabella, and Membranipora membranacea. The macrofouling organisms present in the area may pose problems in submerged equipment and cause some financial loss to the facility; the non-indigenous could be potential threats to the local ecosystem. All seven non-indigenous species are potentially invasive, although their abundance suggests otherwise.

CONCLUSION: A baseline listing of species was generated and showed various species of foulers in the naval base, with Balanus being the dominant species, which is the same as other studies in the Asian region. Seven nonindigenous
species were detected. There is a need to monitor the non-indigenous species, as Mytilopsis sallei (origin: Carribean) has been reported to in huge numbers in the Indo West Pacific region, particularly in Singapore, Hongkong, Thailand, India, Taiwan, China, Malaysia, Japan, and Australia; Brachidontes (Origin: Indo- Pacific) has spread to the Mediterranean and Red Sea.