A large number of round and elongated pockmarks were recently discovered in the Oslofjord, Norway. Pockmarks are formed by expulsion of fluid, most commonly methane or ground water. The elongated shape is a believed to be a result of either strong bottom currents, linear sub-surface weakness zones, the merging of circular pockmarks, or a combination of these factors. The seeping of methane may generate high microbial production, providing a stable nutrient supply to the benthic fauna. Some specialized ‘seep’ species are also known to contain endosymbiotic chemosynthetic bacteria.The benthic macrofauna of five elongated pockmarks were investigated by quantitative sampling and multivariate statistical techniques. The results showed that the faunal composition inside the pockmarks was significantly different compared to the outside, although with a high degree of overlap. The faunal diversity was not higher inside the pockmarks, and no species known to obtain energy by chemosynthetic symbionts were identified. This indicates that methane does not provide an additional nutrient source for the benthic community. Other aspects of the pockmarks are discussed as possible explanations for the different species composition. Eruptive rather than continuous fluid escape may act as a disturbance and remove resident macrofauna inside the pockmarks. Another possible explanation is that the pockmarks act as traps for organic material due to reduced bottom current flow. This could lead to increased organic deposition inside the pockmarks, and in combination with low oxygen content lead to anoxic conditions in the sediment surface layer. Higher abundances inside the pockmarks of opportunistic polychaete taxa (‘indicator species’), such as Capitelle capitata and Polydora spp. were found, indicating that the pockmark sediments might be disturbed. However, the high overall abundance of such opportunists suggests that the study area in general is environmentally stressed. The environmental variables were on the whole similar inside and outside the pockmarks, and correlated only weakly with the species patterns observed.