Stock Assessment of Small Pelagic Fishes Caught by Ring Net Fishery in the Camotes Sea, Central Visayas, Philippines (2003-2012)

Abstract

Majority of the fisherfolks were full-time fishers with monthly income from fishing ranging from Php 1,000-6,000 for the marginal fishers to Php 20,000-100,000 for the commercial fishers. About half of the fisherfolks earned Php 1,000-3,000 per month, while others were fishing for consumption only with an average monthly income of Php 2,700. Both motorized and nonmotorized boats are utilized in most fishing activities except in the gathering of sea cucumbers and shells. The growing importance of ring net fishing in the Camotes Sea has given rise to many speculations regarding its effect on the fishery resources. Most of the marginal fishermen, for instance, believe that the rapid increase in the number of commercial fishing activities that catch small pelagic fishes in the Camotes Sea would, in the long run, lead to the depletion of these fishery resources if not properly regulated. In any fishery investigation, information on stock assessment is deemed necessary, particularly to commercially important species of fish. Information on sexual maturation and sex ratio of many ring net caught fishes in the Camotes Sea is, however, inadequate and hence an attempt has been made to study this aspect of fishery biology in the Camotes Sea. This report presents the findings using the data gathered by NSAP Region 7 on the catch trends of the commercial ring net fishery in the Camotes Sea from 2003-2012, and the population dynamics and exploitation rates of the major fish resources exploited by this fishery. The results are then compared to the findings in an earlier study by Jabat and Dalzell (1988) of the Danao ring net fishery from 1983-1987.

Assessment of Postharvest Losses Due to Catching Undersized Fishery Commodities and Size-Dependent Pricing in the Philippines

“…Based on the assessment conducted by Olaño et al (2018) in Lagonoy Gulf, ring net caught 98% of small-sized pelagic fishes that contributed to the exploitation of juvenile species in the gulf. This also coincides with the findings of Villanueva (2018) and Belga et al (2018) in Davao Gulf and the Camotes Sea, respectively.…”

Population Dynamics of Shortfin Scad (Decapterus macrosoma) Bleeker 1851 in Babuyan Channel, Philippines

“…Length frequency data for all gears were validated and L max was established following the Binohlan and Froese (2009) model. The largest L max observed in the study was 32.8 cm, however, this measurement seems too big for the species and questionable since most of the recorded and published length for this species was only up to 29.5 cm (Lavapie-Gonzales et al 1997;Belga et al 2018;Magallanes et al 2022;. Applying the equation of Binohlan and Froese (2009), the species of D. macrosoma in the Babuyan Channel that matures at 17.64 cm would predict an L max of 31.46 cm.…”

“…D. macrosoma were most abundant during the months of February to April and June, before the onset of the southwest monsoon (June to October), and least observed during the northeast monsoon. In the study of Belga et al (2018), the highest peak of D. macrosoma in the Camotes Sea was observed in April which prevails until June and no more secondary peak was observed after that. This is further supported by the observation of Trinidad et al (1993), wherein the highest production of its congeners in the Philippines happened between March and June ensuing the end of the northeast monsoon and the beginning of the southwest monsoon.…”

“…The stocks are already declining, as observed in different major fishing grounds of the country. The exploitation ratio is already beyond the sustainable level being one of the targeted species by commercial and municipal fishing where high exploitation levels were noted in different parts of the country like Palawan (Ingles and Pauly 1984), Sulu Sea (Lavapie-Gonzales et al, 1997), Tawi-Tawi (Aripin and Showers 2000), Camotes Sea (Belga et al 2018), Eastern Sulu Sea and Basilan Strait (De Guzman et al 2018), and Lagonoy Gulf (Olaño et al 2018). Based on DA-BFARc (2020) available data, a declining catch and catch per unit effort (CPUE) trend for D. macrosoma was observed during the past 11 years in the Cagayan Valley Region starting the year 2007 where a total of 80.30 MT was landed both for commercial and municipal sector (Figure 1).…”

“…Population assessment studies were conducted in some areas of the country in some members of the genus Decapterus, including Decapterus kurroides Bleeker 1855 (Lavapie-Gonzales 1991), Decapterus russeli Cuvier 1833 (Ingles and Pauly 1984), and Decapterus macrosoma Bleeker 1851 (Belga et al 2018) using length-frequency data. However, published studies on population dynamics and fishing patterns still need to be included in Babuyan Channel, Philippines.…”