 Karen Hartman 
 
 Sowerby's beaked whale 
 
 Mesoplodon bidens 
 
 Other names: North Sea beaked whale 
 
 North Atlantic beaked whale Maximum length: Male: 5.5m 
 
 Female: 5.1m 
 
 Calf: 2.4m Maximum weight: Male: 1,300kg 
 
 Female: 1,300kg 
 
 Calf: Unknown Diet: Squid 
 
 Small fish Estimated population: Unknown Unknown IUCN Listing: DD DD CITES Appendix: II II CMS Appendix: Not Listed Not Listed 
 
 Classification: Sowerby's beaked whale was the first of the beaked whales to be discovered.
– How rare is the carcass of a beaked whale that washed ashore in Massachusetts on Friday morning? This rare: "New England Aquarium biologists have been conferring to determine the exact species," officials with the aquarium said in a statement released Saturday, per the Boston Globe. The 17-foot-long female that ended up on a beach in Plymouth is thought to be a Sowerby's beaked whale, a species that the nonprofit Whale and Dolphin Conservation reports is seen only infrequently in the wild but is "one of the most commonly stranded beaked whales." The aquarium last handled a beaked whale in 2006, reports the AP. Per NOAA Fisheries, "At sea, [Sowerby's beaked whales] are challenging to observe and identify to the species level due to their cryptic, skittish behavior, a low profile, and a small, inconspicuous blow at the (water's) surface." And when it comes to being "at sea," the Globe reports the whales are typically found hundreds of miles from the coast on the continental shelf, where commercial fisherman occasionally reel one in. A necropsy is being performed; the aquarium notes the nearly one-ton female "did not have any obvious entanglement gear or scars or obvious trauma from a vessel strike." (This beaked whale may be the deepest-diving mammal on the planet.)