Biologists from the Massachusetts Division of Marine Fisheries detected a white shark off Monomoy Tuesday, according to a press release.
The shark spotted was a 13-foot female that was tagged by researchers in 2011.
This is the first shark detected off the coast of Cape Cod this year.
Researchers believe white sharks come to Cape Cod to feed on the grey seals that migrate to the region every summer.
Officials are reminding beachgoers to use common sense when swimming. They recommend avoiding swimming at dawn or dusk, staying close to the shore and avoiding areas where seals congregate.