Spatial and temporal variations in catch rates and economic value of artisanal fisheries in Myanmar’s Gulf of Mottama: A five-year assessment

The Gulf of Mottama (GoM), Myanmar, is a globally significant coastal wetland that supports artisanal fisheries and local livelihoods, yet long-term fisheries data remain scarce. This study provides a five-year assessment (2020–2024) of catch composition, catch per unit effort (CPUE), and economic value from 15 monitored fishing boats in three coastal sites along the gulf. Using fisher-reported catch records, we analyzed spatial and temporal variation through relative abundance, CPUE trends, non-metric multidimensional scaling (NMDS), and generalized linear models to standardize CPUE for assessing temporal and seasonal effects. A total of 28 species were recorded, but catches were highly concentrated: five species, led by Pama croaker ( Otolithoides pama ) and Flathead sillago ( Sillaginopsis panijus ), accounted for more than 80% of total catch and income. Catch composition differed significantly among sites, while interannual differences were limited. Standardized CPUE varied strongly by site and season, with higher values in the lower and middle sites and during monsoon and cool seasons. Although CPUE showed an apparent increasing trend, fisher reports indicated intensified gear use, suggesting potential effort creep rather than stock improvement. Average annual income per boat ranged from USD 3,238 in the upper site to USD 5,458 in the lower site, reflecting spatial inequalities in productivity and fishing capacity. These findings highlight ecological concentration, seasonal dynamics, and livelihood dependence on a narrow suite of species. The study provides a rare multi-year baseline for Myanmar’s data-limited small-scale fisheries and supports adaptive, site-specific management approaches. • Five-year dataset reveals spatial and seasonal variation in fish catches. • Catches dominated by few species, led by Pama croaker and Flathead sillago. • Catch level is maintained but increasing effort masks stock sustainability risks. • Economic values were nearly double for lower-site fishers compared to upper-site. • Results provide first multi-year baseline for adaptive fisheries co-management.