The Portuguese Water Dog is a breed of working dog as classified by the American Kennel Club. Portuguese Water Dogs are originally from the Portuguese region of the Algarve, from where the breed expanded to all around Portugal's coast, where they were taught to herd fish into fishermen's nets, to retrieve lost tackle or broken nets, and to act as couriers from ship to ship, or ship to shore. Portuguese Water Dogs rode in fishing trawlers as they worked their way from the Atlantic waters of Portugal to the waters off the coast of Iceland fishing for cod.
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