Possessing a great sense of smell and superior tracking instincts, the beagle is the primary breed used as detection dogs for prohibited agricultural imports and foodstuffs in quarantine around the world. The beagle is intelligent. In the United States the beagle ranked 4th most popular breed in 2012 and 2013, behind the Labrador Retriever (#1), German Shepherd (#2) and Golden Retriever (#3) breeds.