A little more info on the Azores/Cape Verde issue:

"The Portuguese connection with New Bedford developed from eighteenth-century whaling. Prevailing winds made the Azores first port-of-call. As ships took on supplies and crew in the Western Islands, as they were traditionally known, the stage was set for Portuguese immigration to New Bedford.
After whaling in the Azores, it was customary to hunt whales around the Cape Verdes and along the coast of Africa before cruising southwest to the Brazil Banks off the east coast of South America, and then home to New England. After 1800, New England whalers ventured into the Pacific and Indian oceans on longer and longer voyages."
http://www.whalingmuseum.org/kendall/old_nb/old_nb_african.html