Rat is generally understood to be a water vole , also called a water rat in the book’s language, not a true rat.

Quick Scoop

In The Wind in the Willows , Ratty lives by the river, rows a boat, and is portrayed as a riverbank creature with a taste for quiet, civilized life.

Species note

  • The character is commonly referred to as “Water Rat” or “Ratty.”
  • Modern references and literary guides identify him as a European water vole.
  • The “rat” label is more of a name/title than a strict biological species name.

Bottom line

So the short answer is: Rat is a water vole, not a rat.