This study investigates the potential of locally available mosquito nets as an alternative material for sandfish ocean nurseries. Mosquito nets (~ 2 mm mesh) were designed into single (SL), double (DL), and triple-layered (TL) to approximate the conventional hapa (CH) with ~ 1 mm mesh normally used in sandfish ocean nurseries. The study was conducted in Maliwaliw island and in a cove in Buyayawon both located in Eastern Samar, Philippines. Results showed that TL had the highest juvenile survival (35.93 ± 10.56%) in Maliwaliw, which was significantly different (p < 0.05) from SL and DL. The DL design showed the highest survival (25.23 ± 17.15%) in Buyayawon by day 60, followed by TL (21.37 ± 3.11%), although not statistically significant. On the other hand, average growth rate was highest in SL in both sites where survival was also the lowest. Biomass, however, was the highest in DL in Buyayawon (1,014 ± 266 g m-2) followed by TL in Maliwaliw (925 ± 107 g m-2). Sandfish juvenile survival in DL and TL were higher than those in the CH in both sites suggesting that mosquito nets can indeed be used as an alternative material for rearing early-stage sandfish juveniles in floating ocean nurseries.

Biophysical characteristics that affect the distribution of sandfish in the sea ranch were investigated to determine indicators for a suitable habitat for sandfish sea ranching. These include sediment grain size, organic matter (OM), chlorophyll a, pheophytin, penetrability, depth and seagrass cover. A total of 5864 hatchery-produced sandfish juveniles were released in seven batches in a 5-ha ranching site in Maliwaliw Island over a period of three years. The 5-ha ranch was divided into three zones, with Zone A (50 × 50 m) being the juvenile release site. Survey of the released sandfish was done quarterly from February 2016 until May 2017 and sediment collection done twice. A total of 750 sandfish weighing 10-600 g were recorded; 23% were <150 g, 59% were 151-350 g, 17% were 351-550 g, and 2% were >550 g. Distribution of substrate parameters between the different sea ranch zones showed no significant differences (p > 0.05). Visualized sediment grain-size data showed multiple cohorts of sandfish with varying sizes in different zones with predominantly medium and fine grains with relatively higher total OM and labile OM. Sandfish >351 g were found in deeper waters (>70 cm at low tide) with lower concentrations of labile OM and chlorophyll a, and higher pheophytin. Sandfish <350 g were found in areas with higher labile OM, higher chlorophyll a and lower pheophytin. Results of this study indicate the need for a sandfish sea ranch site with water depth >30 cm at low tide, and varying sediment particle size and composition to support the different stages of growth and development of sandfish.

Four different techniques in processing sandfish: a) MB-method described by Brown et al. (2010), b) MN- from NFRDI, per Pardua et al. (2018), and two variations of method from Purcell (2014), c) MP1, and d) MP2 which were slightly modified and tried to compare resulting product quality and yield from freshly gutted sandfish. This demonstration was to encourage sandfish ranch managers to add value to their sandfish and ensure better earnings. Twenty-four sandfish individuals (350 to 870 g) harvested from the sea ranch site at Maliwaliw Island were used for processing at six individuals per technique. Results show that live sandfish weight was reduced to 45% after gutting. MB had the highest weight percent recovery from gutted weight at 10.75%, not significantly different (p > 0.05) from MN at 9.65% but significantly higher (p < 0.05) from MP1 (9.38%) and MP2 (9.50%). In terms of product quality, bigger sandfish >600 g produced good quality products when processed correctly. Bêche-de-mer is priced based on three criteria: quality of the product, size length, and weight. Although there is no single best-practice method for processing sandfish, sea ranch managers may opt to adopt the MB and MN for a simpler procedure to save time and resources, and higher product yield for better income. Keywords: Sandfish, processing techniques, yield, balat, product quality.

Since the 1970s, Samar and Leyte islands had a thriving sea cucumber fishery but have rapidly declined over the years. In Maliwaliw Island, anecdotal accounts validated by the community revealed that the island had a brisk sea cucumber fishery but collapsed due to uncontrolled collection. In 2013, a sandfish sea ranching project was implemented in Maliwaliw Island, Salcedo, Eastern Samar, to bring back the sandfish that has disappeared from the area, and subsequently provide a supplemental livelihood to the local fishers. This study was conducted to investigate the impacts and lessons learned from the sandfish project. Recruitment of wild stock, increased community knowledge of sea cucumber biology and ecology, additional income through sandfish bycatch, and perceived enhancement of the coastal marine environment of the island were among the positive gains from the project identified by the respondents. On the other hand, poaching by fishers from neighboring communities resulting in inter-community conflicts was a major challenge. Clearly, the sandfish sea ranching project in Maliwaliw achieved ecological, social, and economic impacts on the project participants and the community. However, these gains need to be strengthened with effective management measures including size regulation to sustain the sea cucumber fishery in the area.