The catch per unit effort (c.p.u.e.) estimated as kg/hr and the yield per recruitment (Y/R) often common by-catch fishes are used in the present paper to investigate the effects of shrimp trawlers on the fisheries status and its environment in the Northwest Arabian Gulf. Samples were collected on weekly basis through fishery-oceanography survey carried out by the Marine Science Centre at the University of Basrah during the period of 1995-1999, using two small shrimp trawlers. The catch per unit effort (c.p.u.e.) of total, commercial fishes, shrimps, and other invertebrates catches showed a drastic drop year by year. The results of the relative yield per recruitment (Y′/R) of the ten investigated species, their optimum and current lengths at first capture (Lc) and their lengths at first maturation (Lm) indicate that the stock of these species suffered a problem of recruitment overfishing. A strategy of protection for Northwest Arabian Gulf fisheries involves implementing closed season, introducing an effort limitation policy should be designed.