Three more Jersey Shore towns have formally joined a growing movement by banning plastic bags in an effort to reduce pollution on beaches and in the ocean.

The bag bans went into effect Saturday, June 1, in Brigantine, Avalon, and Stone Harbor, and repeat violators face fines of up to $500 in the three towns.

Enforcement efforts come amid a growing number of reports of whales and other sea mammals being found dead with plastic in their stomachs.

In Brigantine, supermarkets, drugstores, food marts and restaurants can no longer provide single-use carry-out bags made of plastic.

On Seven Mile Island — shared by Avalon and Stone Harbor — retailers can no longer distribute plastic bags, plastic straws, or Styrofoam food containers. Stone Harbor also is banning plastic foodware, including cutlery, containers and bowls.

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Other Shore towns with plastic bans or fees for plastic bags include Beach Haven, Belmar, Bradley Beach, Harvey Cedars, Little Silver, Long Beach Township, Longport, Monmouth Beach, Point Pleasant, Somers Point, and Ventnor, according to the Association of New Jersey Environmental Commissions.