The seasonal shrimp fishery off Periathalai in the Gulf of Mannar was studied for a period of three years from
2000 to 2002 and the results obtained were compared with those of the earlier observations carried out by
the authors during the years 1985 - 1987. The most striking difference in the fishery between the two periods
was found to be in the species composition. From the exclusive occurrence of a single species of shrimp viz.,
Penaeus indicus during the previous investigation one more commercially important shrimp P.semisulcatus
was observed to contribute to the fishery significantly during certain months. The annual estimated landings
fluctuated widely from 9 t to 213 t in the present observation as against a more or less uniform trend, with
only marginal fluctuation ranging between 96 t to 107 t, recorded earlier. Mature and spent-recovering
females constituted significant proportions during both the observations.