Evaluation of the catch assessment strategies of Tanzania Marine Fisheries

The study evaluated the current sampling strategy, data quality, and estimation procedures used in eCAS system, aiming to improve catch assessments that are fundamental for effective fisheries management and stock assessment. Findings reveal that, sampling intensity frequently remained below protocol targets, with inconsistencies and a general decline after 2020. Several districts and landing sites experienced prolonged periods of low or no sampling, while most fishing gears were inadequately represented. Data quality issues included incomplete records, duplicated entries, implausible trip information, and limited species reporting per trip, despite the multispecies nature of the fishery. Comparison with recalculated estimates showed that system generated eCAS outputs were generally lower, suggesting possible effects of missing effort data, outdated frame survey information, and estimation inconsistencies. The study concludes that while the eCAS system has improved fisheries data collection and reporting, critical gaps in sampling coverage, data validation, and estimation procedures must be addressed to ensure more accurate, representative, and actionable fisheries statistics for sustainable resource management.