page_title: American water shrew
section_title: Dentition and eating habits
hierarchical_section_title: American water shrew / Dentition and eating habits
caption_attribution_description: English: Skull of American Water Shrew (Sorex palustris); record ID: nmnheducation_10026394
context_page_description: The American water shrew or northern water shrew, is found in the nearctic faunal region located throughout the mountain ranges of the northern United States and in Canada and Alaska.
context_section_description: The American water shrew has a larger skull ranging from 21–23 mm (0.83–0.91 in) and width 10–11 mm (0.39–0.43 in) and has a dental formula of  × 2 = 32 teeth. They swim well and make short dives in search of food. The shrew prefers aquatic insects such as stoneflies and craneflies. They are known to also feed on small fish, vegetation, and snails. Shrews require much food and cannot go without food for any more than three hours because of their high metabolic rate. They are thought to use echolocation to help find prey.
caption: Skull of Sorex palustris
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