The phrase "vermin hunter" refers to a person or animal that catches or kills small, unwanted animals such as rats or mice. They are called "vermin" because they can cause damage or spread disease. Full definition
The Schipperke or Skips, as they are nicknamed, is breed that was breed to be a watchdog, a companion, and as vermin hunters in Belgium. (second-opinion-doc.com)
Other examples of vermin hunters are Parson Russel terriers, cairn terriers, lakeland terriers, West Highland white terriers and Scottish terriers. (cuteness.com)
Vermin hunters like the Jack Russell Terrier, Scottish Terrier and West Highland Terrier are energetic, independent and do best on a leash when outdoors. (my-favorite-dog.com)