It was once thought that this pinniped raked the ocean floor with its tusks to look for food
It's just like 
a refrigerator ...... trawling could damage the sea floor, deplete shrimp and clam... [DOC] [TLE] 1000+ ideas about Ocan Arctique on Pinterest [PAR] A primitive ocean on Mars held more water than Earth's Arctic Ocean, and .... of 
the calcified shells of marine protozoa that once lived on the ocean floor."