Assessing the scale and ecological impact of derelict and discarded fishing gear across Thailand via the MARsCI citizen science protocol.

South-East Asia is among the least studied regions for the growing issue of marine debris pollution, despite being a major contributor towards global marine debris. In the present study, we provide the preliminary results from the MARsCI project, a survey protocol designed to utilise citizen science to facilitate data collection on the ecological impact of discarded fishing gear (DFG) in Thailand. Over a three-year period, 103 surveys were carried out across Thailand, resulting in impact assessment of 606 pieces of DFG. Our findings indicate corals are regularly impacted by DFG in Thai waters and that isolated marine habitats may be more severely impacted than near-shore sites. We further identify crabs, muricid snails, and demersal fish to be among the most regularly entangled animals. We discuss our findings in the context of earlier work from Thailand, and conduct a critical review of the protocol itself, identifying improvements for future efforts.

First successful head-start program of leatherback sea turtles (Dermochelys coriacea) in Thailand and proposed dietary strategy.

Leatherback sea turtle (Dermochelys coriacea) hatchlings have previously been kept alive for over a year in captive conditions but these were the few survivors of initially larger groups. In this report, newly hatched leatherback sea turtles were randomly harvested from two nests in Thailand and successfully reared before release back to the wild. In captivity, the survival of the turtles decreased sharply during the first 4 or 5 months, and then steadied until the end of the 12-month trial. The survival of yearlings from one nest was 13.3% and from the other nest 46.7%. Their growth was exponential, reaching 1.36-3.35 kg (n = 9) at the end of program. The causes of death of the reared turtles were accidents (25.0-38.5%) and infections from water and live food (61.5-75.0%). The dietary requirements of the turtles were investigated by determining the digestibility of protein and carbohydrate in vitro, using enzymes from the digestive tracts of hatchlings that had died in an accident (70.1-92.9 g body weight). The results indicated that the most suitable source of protein was wheat gluten, followed by soybean meal, nonruminant meat and bone meal, fish meal, nonruminant meat meal, pork meal, and skimmed milk, while suitable carbohydrate sources were mashed cassava, corn, wheat flour, and alpha starch, followed by cereal meal and rice flour. Findings from the current report provide a practical protocol for head-starting leatherback sea turtles, and indicate the possible basis of an effective artificial diet for this species.