No. 45–Dolphin or Porpoise?

The short answer is dolphin. Bottlenose dolphins ply our local waters. Members of the porpoise family (Phocoenidea) which contains six species are smaller than most dolphin species and with one exception inhabit colder water. The range of the vaquita porpoise (Phocoenidea sinus) is limited to the Gulf of California and no species are found in the western Atlantic.

Whales, dolphins, and porpoises evolved from a common land dwelling ancestor that lived 50 to 55mya. As I’ve now become accustomed to, I found disagreement on the exact phylogeny of the order Cetacea. There’s a dustup between the molecular and morphological camps over whether cetaceans are more closely related to today’s horse or the hippopotamus. There is also disagreement over the classification of river dolphins and the species and or subspecies classification of some oceanic dolphins.

What is agreed upon is that there are two suborders of Cetacea. They are Mysteceti, (baleen whales) and Odontoceti, (toothed whales) which includes dolphins and porpoises.

The bottlenose dolphin resides in the family Delphinidae and is known scientifically as Tursiops truncates. Delphinidae is the largest and most diverse family and includes killer and pilot whales.

The bottlenose is the largest of the “beaked” dolphins with males reaching up to 13 feet in length and weighing in at 1,400 plus pounds. They range widely throughout the worlds warm oceans and seas generally preferring shallow inshore waters. Atlantic coast bottlenose may be found as far north as Cape Hatteras in the summer and year round in Florida. Though primarily a shallow water species there are populations found off shore to the edge of the continental shelf.

The history of bottlenose and human interaction is a mixed bag. Greek legend has them saving humans from drowning and shark attack while some fishermen today see them as competition and kill them. Oceanariums discovered them to be a cash sea cow in the late ‘40s and our navy trains them for surveillance of ships and harbors for explosive devices while developing a new generation of radar many believe to be harmful to cetaceans.

While researching this piece I came across the following: “Dolphins have been hunted by people in many parts of the world for meat and products (such as fertilizer, body oil for cooking and illumination, and jaw oil used as a lubricant in fine machinery) made from dolphin parts.” *

I also came across this: “The NOAA Fisheries Service is responsible for enforcing the Marine Mammal Protection Act of 1972, which safeguards whales, dolphins, porpoises, seals, sea lions, walruses, manatees, sea otters and polar bears in U.S. waters and territories. Under the MMPA and its implementing regulations, it is illegal for people to “harass” or feed any marine mammal in the wild. Harassment is specifically defined in the MMPA as any act of pursuit, torment or annoyance that has the potential to injure the animals or disturb their behavior. Feeding or attempting to feed wild marine mammals is also explicitly prohibited.”**

*animaldiversity.ummz.umich.edu/site/index.html

** NOAA Magazine – noaanews.noaa.gov