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MARINE MAMMALS 



Presented here are keys to marine mammals of the North American 

 west coast. These are preceded by a glossary and are followed by species 

 accounts that refer to geographical and seasonal occurrence. Invaluable 

 aids to us were the information and keys in Scheffer (1958) and Tomilin 

 (1957); we hereby acknowledge the work of those authors. The biblio- 

 graphy, after the species accounts, contains complete citations of 

 these books. Following the bibliography is a list of agencies interested 

 in reports of marine mammals found dead on beaches. 



Marine mammal carcasses are often difficult to distinguish, especially 

 if they are not very fresh. Compared to marine birds, they are rather 

 limited in their variety of sizes, shapes and colors and thus differences 

 among them are less distinct. Therefore, the mammal species accounts 

 offer few additional identifying morphological characteristics. Also, 

 in several instances the mammal keys lead only to a group of similar 

 species because further identification is exceedingly difficult. One 

 should at least attempt to identify a carcass to a major group; for 

 example, it is usually relatively easy to distinguish between a fur seal, 

 seal and sea lion. Beyond that, identification becomes increasingly 

 difficult; for instance, in dolphins and even seals you will likely have 

 to consider the shape, placement and number of teeth in each side of the 

 upper and lower jaws. Some species within certain groups of seals and 

 dolphins cannot be readily distinguished unless the skull is examined. 

 Key out mammals as far as you can. If you wish to know more, then refer 

 to other publications listed further on and contact one of the agencies 

 listed at the end of this section. Make it clear that if they inspect 

 or collect the carcass (and often someone will) you would like to know 

 more about it. Whatever you do, leave the carcass on the beach; it is 

 against the law to remove it without a permit. 



