Eimeria wobeseri sp. n. and E. goelandi sp. n. from the kidneys of nestling herring gulls (Larus argentatus) are reported. Species descriptions are based on the morphology of sporulated oocysts. Oocysts of one or both species were recovered from 90 of 100 gulls. Nine of 16 gulls rigorously examined were found infected simultaneously with both species. Meronts, gamonts and zygotes were observed histologically in epithelial cells of distal tubules, collecting ducts and ureters. Sporulated oocysts with thin walls and micropylar caps were present within or near collecting ducts and were identified as E. goelandi sp. n. An electron-lucent outer layer and electron-dense inner layer of the oocyst wall, the ultrastructure of the oocyst wall at the micropylar cap and endogenous sporulation of E. goelandi sp. n. are unique observations for a member of the genus Eimeria.