Observations on the stranded marine turtles and mammals in a stretch of 10 km at Gahirmatha Beach, Orissa during 1983 to 1987 are reported here. The washed ashore marine turtles were due to the result of turtles getting entangled and drowned in fishing operations conducted off Paradip and adjacent area, the carcasses drifting northwards and ashore at Gahirmatha. In 1983 around 7S00 olive ridley Lepidochelys olivacea were washed ashore and the curved carapace length in cm varied from 51-72 (62.2) and the carapace width in cm varied from 48-63 (57.8). The number of stranded turtles was reduced to 360 in 1987 and this is due to the effective steps taken to enforce the Wildlife (Protection) Act by the State Forest Departments. Strandings of Humpback dolphin Sousa chinensis, Snubfin dolphin Orcaella brevirostris and Finless black propoise Neophocaena phocoenoides were also recorded. Mortality of nesting females during arribada could have an adverse effect on the breeding population of olive ridley visiting the rookery and consequently on recruitment. A careful study is needed to take preventive and precautionary regulatory measures to be adopted in specific type of fishing operations during the nesting season of olive ridley.