Detectability and impact of repetitive surveys on threatened West African crocodylians

West African crocodylians are among the most threatened and least studied crocodylian species globally. Assessing population status and establishing a basis for population monitoring is the highest priority action for this region. Monitoring of crocodiles is influenced by many factors that affect detectability, including environmental variables and individual- or population-level wariness. We investigated how these factors affect detectability and counts of the critically endangered Mecistops cataphractus and the newly recognized Crocodylus suchus. We implemented 195 repetitive surveys at 38 sites across Côte d’Ivoire between 2014 and 2019. We used an occupancy-based approach and a count-based GLMM analysis to determine the effect of environmental and anthropogenic variables on detection and modeled crocodile wariness over repetitive surveys. Despite their rarity and level of threat, detection probability of both species was relatively high (0.75 for M. cataphractus and 0.81 for C. suchus), but a minimum of two surveys were required to infer absence of either species with 90% confidence. We found that detection of M. cataphractus was significantly negatively influenced by fishing net encounter rate, while high temperature for the previous 48 h of the day of the survey increased C. suchus detection. Precipitation and aquatic vegetation had significant negative and positive influence, respectively, on M. cataphractus counts and showed the opposite effect for C. suchus counts. We also found that fishing encounter rate had a significant negative effect on C. suchus counts. Interestingly, survey repetition did not generally affect wariness for either species, though there was some indication that at least M. cataphractus was more wary by the fourth replicate. These results are informative for designing future survey and monitoring protocols for these threatened crocodylians in West Africa and for other endangered crocodylians globally

Post forest fire management at tropical peat swamp forest: a review of Malaysian experience on rehabilitation and risk mitigation

Malaysian Peat swamp forests constitute a significant component with an estimated 1.54 million hectares remaining. More than 70% of these peat swamp forests are in Sarawak, less than 10% Sabah in and the remainder 20% in Peninsular Malaysia (UNDP, 2006). Peat swamp forest is the fragile unique forest ecosystem type that usually found in the lowland of tropical forest areas. Peat forest is exposed to the fire even especially during the dry season. The impact of forest fires at the peat swamp area not only destroys the above ground biomass but also penetrates the underlying peat, resulting in undesirable environmental impacts, including high atmospheric emissions of carbon gases. Therefore, undertaking the rehabilitation and fire risk mitigation activities at burned peat land is very tough and challenges due to the massive destruction and changes in the ecosystem. This paper will emphasize more on restoration and rehabilitation as well as fire risk mitigation efforts on burn peat swamp forest in Malaysia. The issues and challenges encountered in order to restore the burn peat swamp forest area will also be addressed

A review on the improvement of cladocera (Moina) nutrition as live food for aquaculture: using valuable plankton fisheries resources

Since formulated feed for this purpose has not yet been established effectively, the features of live feeds in the performance of marine and freshwater larval rearing is essential. Hence, to succor growth productivity and to introduce newly livestock species into aquaculture industry, support for the stage of larval rearing must be improved and, better nutritional options must be applied. Furthermore, the natural feeding habits of fish needs live food rich in protein for improved growth, enhanced reproduction as well as survival. Common enrichment protocols, such as oil emulsion, are relatively expensive and consequently, increase overall production cost in hatcheries. The above factors have moved scientists to focus more on development of low-cost, live feed substitutions to ensure success of larval feeding in aquaculture. Larval feed performance depends directly on improvements in finding a better low-cost live feed technology for a better zooplankton and phytoplankton production. Cladocerans like Moina sp. have recently been explored as a potential live feed alternative to boost fish and shrimp larval cultivation in hatcheries. The increase in demand for fish as a source of protein for human consumption requires advancement in the development of aquaculture technologies and, emphasis is well placed on improving supply of live food organisms to assist in the larval development process