Killer whale
Information for offshore regions and warmer waters is more scarce, but widespread sightings indicate the killer whale can survive in most water temperatures. They have been sighted, though more infrequently, in the Mediterranean, the Arabian Sea, the Gulf of Mexico, and the Caribbean. Over 50 individual whales have been documented in the northern Indian Ocean, including two individuals that were sighted in the Persian Gulf in 2008 and off Sri Lanka in 2015. Those orcas may occasionally enter the Red Sea through the Gulf of Aden. The modern status of the species along coastal mainland China and its vicinity is unknown. Recorded sightings have been made from almost the entire shoreline. A wide-ranging population is likely to exist in the central Pacific, with some sightings off Hawaii. Distinct populations may also exist off the west coast of tropical Africa, and Papua New Guinea. In the Mediterranean, killer whales are considered "visitors", likely from the North Atlantic, and sightings become less frequent further east. However, a small year-round population is known to exist in the Strait of Gibraltar, mostly on the Atlantic side. Killer whales also appear to regularly occur off the Galápagos Islands.
North Atlantic right whale
Parts of the western group, especially for those seen regularly in the Gulf of St. Lawrence, display different migratory or calving routines than other whales and these are so-called "Offshore Whales". There could be various areas along or off the west coasts where could have been frequented by whales potentially and might be re-colonized in the future such as Quoddy, Eastport, Plymouth Harbor, Sagamore Beach, Island of Nantucket, Florida Bay, Pamlico Sound, Gulf of Mexico (as far as to Texas), Bahamas, Long Island Sound and vicinity to New York City, the mouth of Potomac River, Delaware and Chesapeake Bay, the mouth of Altamaha River, Cape Canaveral, Sebastian Inlet and around Melbourne, and so on. As the population grows, it's also highly possible that more whales would start using rivers or river mouths, shallow estuaries, smaller inlets or bays. Whales have already seen repeatedly at various of these such as Indian River Inlet, Delaware River, Cape Cod Canal, Jacksonville Drum, and so on.