Gray whale straining water from its mouth (photo- 

 graph courtesy of Jim Cubbage). Gray whales are 

 "baleen" whales instead of teeth, they have numer- 

 ous long overlapping strips of elastic fingernail-like 

 material, called baleen (inset), hanging from their 

 upper jaws that they use to filter out food (photograph 

 from Gulf of the Farallones National Marine Sanctu- 

 ary). "Whale watching" is a popular activity in the Gulf 

 of the Farallones and helps to highlight the important 

 ecological roles played by marine mammals. 



Marine Mammals 49 



