Fate and effects of Ekofisk crude oil in the littoral of a Norwegian fjord

Field experimental studies of the effects of Ekofisk crude oil on the intertidal rocky-shore and rock-pool faunas were carried out in a fjord in western Norway. Chemical analyses indicate a rapid loss of oil from these habitats due largely to physical removal by tidal and wave action. Amphipods and other mobile crustaceans showed avoidance responses to the presence of the oil, although such behavioral responses were often insufficient to prevent significant mortality. Among the sessile fauna, significant mortalities of spat of Balanus balanoides were observed due to experimental oilings, although adult Balanus were affected only at an extremely high level of oil application.