Boston’s WHDH reports that swimmers have been warned to stay at least 300′ away from seal colonies. The large seal population in the area is believed to be responsible for the increase in white shark sightings over recent years, as the seals are a natural prey item for the shark.

The warning comes after multiple credible white shark sightings were reported in the area over the past week, as well as reports of seal carcass sightings.