Figure 4. — A fin whale in the North Atlantic with the paired blowholes 

 open during respiration. The paired blowholes distinguish this animal as a 

 baleen whale. (Photo by W. A. Watkins.) 



the common name most often used in the western North 

 Atlantic' It may be noted that some of the authors are in 

 parentheses. This indicates that though the species name has 

 remained the same since the date of naming the species has 

 since been assigned to another genus. Because the species are 

 not arranged in taxonomic order in this field guide, the page 

 of the synoptic account of each is p "ovided in the column to the 

 right. 



DOLPHIN OR PORPOISE 



There is still considerable controversy over the correct 

 usage of the terms dolphin and porpoise. As mentioned in the 

 preceding section, common names of any species may vary 

 from locale to locale and even from individual to individual. 

 Some persons argue for the use of the term porpoise for all 

 small cetaceans. Others insist on the term dolphin. Still 

 others either randomly use the terms or call members of the 



' Most common names are based on some characteristic of the species 

 (e.g.. spotted dolphin, striped dolphin, rough-toothed dolphin); others 

 are the names of authors of the species (e.g., True's beaked whale) or of 

 habitats or macrohabitats which they inhabit (e.g.. North Sea beaked 

 whale and harbor porpoise); the origins of some common names, however, 

 are less obvious (e.g.. dense-beaked whale), and of less use in field 

 references. 



family Delphinidae dolphins and members of the family 

 Phocoenidae porpoises. The evidence supporting any one of 

 these positions is confusing at best and no usage of terms 

 appears to be without problems. We see no wholly 

 satisfactory resolution to the problem at this time. For all 

 these reasons, we have little desire to defend our decision to 

 follow the last of these practices in this guide, referring to all 

 members of the family Delphinidae for which the term 

 dolphin or porpoise appears in the common name as dolphins, 

 and to the one member of the family Phocoenidae represented 

 in the western North Atlantic, Phocoerm phocoena, as the 

 harbor porpoise. Although all cetaceans may be regarded as 

 whales, the term "whale" most commonly applies to the 

 larger animals. For all species treated, other common names 

 by which they may be known are also listed. 



Detailed treatment of the relative merits of the various 

 terminologies is inappropriate here. Furthermore, it is our 

 opinion that the usage of the terms dolphin, porpoise, and 

 whale as part of the common names of cetaceans is largely a 

 matter of personal preference. 



ORGANIZATION OF THE GUIDE 



The differences between baleen and toothed whales are 

 easy enough to see in animals washed up on the beach or 

 maintained in a tank at a zoo or aquarium. But since an animal 

 at sea can seldom be examined that closely, its most obvious 

 characteristics may be its overall size, the presence or 

 absence of a dorsal fin, its prominent coloration or markings, 

 its general behavior, or its swimming, blowing, and diving 

 characteristics. For that reason, regardless of their scientific 

 relationships, all the whales, dolphins, and the one porpoise 

 covered in the main text of this guide are divided into three 

 groups. Those over 40 feet (12.2 m) long are discussed in the 

 section on Large Whales, those from 13 to 40 feet (4.0 to 12.2 

 m) in the Medium- Sized Whale, and those less than 13 feet 

 (4.0 m) in the Small Whales, Dolphins, and Porpoise (with a 

 dorsal fin). There are no small whales, dolphins, or por- 

 poises in this region without a dorsal fin. Each section is 

 further divided into those animals with a dorsal fin and those 

 without. From that point, animals likely to be confused in 

 the field are grouped together and the important differ- 

 ences between them are discussed. 



The synoptic accounts of the species are followed by five 

 appendices: Appendix A discusses and illustrates man-made 

 and applied tags and natural markings on cetaceans and their 

 importance in studies of natural history. Appendix B 

 discusses the data which are most important to record in 

 observations of cetaceans at sea, gives examples, and 

 provides blank sighting forms. Appendix C discusses possible 

 causes of cetacean strandings and the manner in which 

 stranded animals should be handled and adds a key and tables 

 to aid in identifying stranded cetaceans. Appendix D 

 provides guidelines for collecting data on stranded cetaceans 

 and provides forms and specific instructions for taking 

 standard measurements. Appendix E lists institutions to be 

 contacted in the event of a cetacean stranding or for 

 information. 



A bibliography of useful references on cetaceans in 

 general and cetaceans of this region in particular and a 

 directory to species accounts are included. 



