Grey seals are sexually dimorphic (2 distinct gender forms) in both size and coloration. Males are significantly larger with thicker necks and shoulders than females. Males also have wider, more rounded snouts and a darker coloration than females. However, both sexes are some shade of black with white specks and splotches that vary from whiteish to black in color.

Populations appear to be increasing in most areas of their habitats. They are not threatened with habitat destruction or habitat fragmentation.

Listed as of "least concern" on the IUCN Red List (International Union for Conservation of Nature and Natural Resources).