The Fishery Potential of Freshwater Gobies in Mandulog River, Northern Mindanao, Philippines

Freshwater gobies, particularly fry and some adult species, have been used as an alternative fishery resource. Mandulog River in Iligan City, northern Mindanao, Philippines, is one of the areas known for goby-fry fishery. This study described the potentials of the goby population in Mandulog River in terms of its fishery aspects. Households along the Mandulog River were the respondents of the survey. Results show that most of the freshwater gobies were caught as alternative food while goby-fry were sold in the market. Goby fishing was done five times a year using nets and traps. The maximum catch per fishing session was one to three kilograms and sold at more or less PHP 10 (Philippine Peso) (USD 0.23) per kilogram. Monthly income from goby fishing was from PHP 100 to PHP 200 (USD 2.35 to USD 4.71) only. Goby species such as Sicyopterus lagocephalus, Oxyeleotris lineolata, Awaous melanocephalus, A. ocellaris, Giuris margaritacea, and Rhyacichthys aspro were the preferred prey species. Findings suggest that goby fishing was not a major source of livelihood as fishers were not earning much from it. However, as a bycatch, the goby population is under threat, with their economic and ecological benefits not utilized. Destructive fishing methods such as cyanide fishing, electric fishing, and use of fine mesh nets might also adversely affect the goby population, despite being non-target species. Therefore, protection of target species from overexploitation would also benefit the goby species.