The Fisheries Research Department conducted a pilot study to investigate the spatial and temporal distribution of spawning aggregations and nursery areas for Lutjanus sebae (Red emperor snapper). The goal of the pilot study was to conduct fieldwork that would test proposed research methodologies in preparation for upcoming research cruises scheduled for 2026.

The first phase of the research began in early 2025 with an interview-based survey conducted on Mahé, Praslin, and La Digue. Through semi-structured questionnaires, information was gathered from fishers and divers regarding potential locations, habitat types, and seasonality for both adult and juvenile Red emperor snapper. This information was then used to develop a survey methodology and a map identifying potential spawning aggregation sites and nursery areas.

For nursery areas, the method of Underwater Visual Census (UVC), along with transects and point counts, was employed to observe and tally any juveniles encountered along a measured transect. The habitat was also recorded during these observations. Although customized traps were intended to be used for capturing and releasing juveniles in potential nursery areas, they were not ready in time; therefore, two standard traps were utilized instead.

In terms of spawning aggregation sites, no aggregations of Red emperor snappers or any other demersal species were encountered. As a result, the full methodology could not be tested. However, one or two Red emperor snappers were caught using hook and line, and metric measurements were taken as planned.

For spawning identification, gonad extraction and collection were planned. While the methodology for extraction was successfully executed, gonad samples could not be collected as the fish caught were not from aggregating individuals.

Pilot studies are essential before scientific research is conducted, as they lay the foundation for the project. During this phase, trial and error processes are thoroughly reviewed and adjusted. Although not all planned activities were completed, effective teamwork ensured a smooth and successful survey. Moreover, valuable insights were gained, which will aid in improving methodologies and determining the next steps for 2026.