How do you recognize a member of the Coast Guard? First of all from an official document that identifies it as such and specifies its role. Herman had both. The document was issued by the captain of the port of Baltimore, in the United States. The role was specified in the document itself: expert rat hunter.
Yes, because Herman was a cat. And what a cat! Gray with green eyes, he was the Coast Guard’s first feline. He was formally hired in 1943, at the age of eight months, as evidenced by the identity document complete with paw prints.
To enable him to fulfill his assigned mission, Herman had 24-hour access to the port and ships.

Felines have been a more or less fixed presence on ships since ancient Egyptian times, precisely by virtue of their ability to track down and kill mice, rats and various rodents that infested boats.
The role of cats was threefold useful: by killing these animals they prevented them from infecting the crew (mice can transmit many diseases to humans), from spoiling the food or from damaging the ship’s structures.
Historically polydactyl cats, i.e. with more toes than normal, were preferred because they were faster and therefore easier to chase rodents.
The use of cats on ships has decreased since the 1970s due to hygiene issues, but their role in the military has not disappeared, it has simply become less operational.
Today they serve mainly as mascots and as moral support for women and men engaged in battle.