[Illustration: Appendix Figure C1.--Whales and dolphins, like this mixed school of false killer whales and bottlenosed dolphins, sometimes strand themselves individually or as entire herds for a complex of still incompletely understood reasons. (_Photo from Japan by S. Ohsumi._)]
Cetaceans may be found during or shortly after the stranding or many months later, when the carcass is bloated or rotted nearly beyond recognition. If the stranded animal is alive or freshly dead, it can be identified by any of the characteristics itemized in the text. But even if it is in an advanced stage of decomposition it can be identified using the key below. In general numbers and descriptions of teeth (Table 1) and numbers and descriptions of baleen plates (Table 2) persist longest as reliable identifying characteristics. If they are still detectable on the carcass, numbers and lengths of ventral grooves may also be used to separate the balaenopterine whales.[17]
[Footnote 17: The tables were prepared primarily from Tomilin (1967) and supplemented by miscellaneous published papers and our own observations. The sections on toothed whales in the key were developed following the general outline of Moore (1953).]
In order to use the key below, begin with the first pair of opposing characteristics--one of the two will apply to the specimen you are examining. On the line following that statement there will be a paragraph number, go to that paragraph. There you will find two more paired, opposing characteristics. Again, one of the two will apply to the specimen you are examining. Select that one and go to the paragraph indicated on the line following it. Continue this procedure until the statement which is true for your specimen is followed by a species name instead of a reference to another paragraph. This name identifies the specimen. To verify your identification go to the discussion of that species in the text. With a little practice and careful attention to details, identification of whales, dolphins, and porpoises will become easier.
KEY TO THE IDENTIFICATION OF STRANDED CETACEANS OF THE WESTERN NORTH ATLANTIC
1. a. Double blowhole; no teeth present in either jaw; baleen plates in upper jaws. (Baleen whale) Go to 2