Why Did Ships Have Cats Onboard? Everything You Ever Wanted to Know

Curious why ships used to have cats sailing the high seas with their crews? You’re not alone! From pest control to good luck charms, ship’s cats have a fascinating and storied history. In this post, we break down everything you need to know about ship’s cats.

Whether you work in maritime, love cats, or just want to impress your quiz team, read on!

What Is a Ship’s Cat and Where Did the Tradition Start?

A ship’s cat is simply a cat that sailed with human crews on their ships, sometimes as a pet, sometimes as a valued worker. The tradition stretches back thousands of years, as far as Ancient Egypt, when hieroglyphics depicted cats journeying with traders around the Mediterranean. For centuries, having a cat aboard became almost as common as having an Able Bodied Seaman.

Sailors considered cats part of the crew. Over time, these furry companions took on roles far beyond casual mascots, often regarded as essential parts of any successful voyage.

Read more: The Mysterious World of Ghost Ships & Some Famous Examples

Why Did Ships Carry Cats in the First Place?

Cats were brought onboard ships for several reasons:

• Pest Control: Ships were prime real estate for mice and rats attracted to stored food, grain, and other cargo. Rodents not only destroyed vital supplies but also carried deadly diseases like the plague. Cats hunted these unwanted stowaways, protecting food stores and helping crews stay healthy.

• Morale and Companionship: Months at sea could get lonely and stressful. Cats provided entertainment, relaxation, and a much-needed sense of normalcy. Sailors would enjoy the company, and sometimes even teach their ship cats tricks for fun.

• Good Luck and Superstition: Seafarers have always been a superstitious bunch. Cats, especially black ones, were seen as good luck. Many believed that a cat on board would keep storms and bad luck at bay, and in some cultures, cats were even credited with supernatural powers.

• Entertainment: Before smartphones and streaming, sailors often amused themselves by watching cats at play or interacting with them during quiet times at sea.

How Did Ship’s Cats Actually Help with Pest Problems?

The real value of a ship’s cat? Hunting down rats and mice that threatened to overrun food stores, eat into cargo, and compromise the ship’s hygiene. Rodents were a serious problem: they contaminated food, spread illness, and could even chew through ropes and wood, damaging the ship’s structure. A cat’s natural hunting instincts make them the perfect “pest control officer.”

Read more: What is the Dark Fleet? From Political Tensions to Sci-Fi

Cats would patrol the ship, using their keen senses to track and hunt rodents. This wasn’t just about comfort; it protected the crew’s health and their livelihoods by safeguarding vital supplies and stopping disease outbreaks.

Did Having Cats Also Boost Crew Morale?

Absolutely. Life at sea could be tense, isolating, and even perilous. The presence of a friendly animal, someone to pet, talk to, or just watch as they lazed in a sunny patch, helped break up the monotony and reduce stress. Cats gave sailors a sense of home and stability, improving overall morale on long voyages. Stories of beloved ship’s cats abound, with some even remembered in ship logs and crew journals.

Did Sailors Really Think Cats Brought Good Luck?

Yes, it’s true - sailors throughout history have relied heavily on superstition and tradition. Many believed cats, especially black ones, could ward off storms and disasters. They became symbols of good luck and protection at sea. Some cultures thought seeing a cat’s grooming behavior could predict the weather; for example, if a cat washed its face, rain was supposedly on the way!

Read more: 13 (Unlucky for Some!) Sailors’ Superstitions

Are Ship’s Cats Still Allowed on Modern Ships?

Mostly, no. While the tradition continues on some privately owned vessels, most commercial and military ships no longer allow cats onboard. In the 1970s, organizations like the British Royal Navy and US-flagged fleets officially banned pets (including cats) from their vessels due to health and hygiene concerns.

Additionally, the risks became apparent: when ships docked, cats could escape, go ashore, and damage local wildlife or breed with native populations. This has led to environmental issues, including the extinction of certain bird and small mammal species due to roaming non-native felines.

Nowadays, pest control is usually achieved through chemicals and modern sanitation methods rather than furry crewmates.

What Happened to Cats Who Escaped from Ships?

Not every cat stayed loyal to its ship and crew. When ships arrived at port, cats sometimes slipped off to explore or were even brought ashore by homesick sailors. If cats were released in areas where they weren’t native, they sometimes established feral colonies.

In certain cases, escaped ship’s cats are blamed for harm to native wildlife, especially on remote islands where local birds and reptiles had never encountered such agile predators before. This unintended consequence contributed to bans on pets aboard many vessels.

How Did Ship’s Cats Become Part of Maritime Culture?

Over generations, cats became firmly entwined with the maritime world, appearing in folk tales, ship names, and even official naval records. Some cats became legends in their own right. A few, like the famous Unsinkable Sam, survived multiple shipwrecks and were adopted as mascots by several crews. The presence of cats in maritime history is celebrated in art, collectibles, and stories to this day.

Do Any Ships Still Have Cats Aboard Today?

In some cases, yes. Privately owned boats and yachts occasionally welcome cats for pest control or companionship. However, almost all commercial, military, and state-operated vessels now forbid the practice due to regulations on hygiene, animal welfare, and environmental protection.

What Are Some Famous Ship’s Cats from History?

A few ship’s cats have gone down in history books and seafaring legend:

• Unsinkable Sam: Originally named Oscar, this cat survived the sinking of three ships during WWII: the Bismarck, HMS Cossack, and HMS Ark Royal. He’s remembered as one of the most resilient and well-traveled ship’s cats.

• Mrs. Chippy: A cat belonging to a carpenter aboard Shackleton’s Endurance. Highly regarded by crew, Mrs. Chippy’s story is bittersweet—a reminder of the bond between sailors and their shipmates, feline or otherwise.

Why Did Maritime Organizations Ban Cats from Ships?

By the 1970s, organizations like the British Royal Navy and US maritime authorities stopped allowing cats (and other pets) on ocean-going ships. Concerns included:

• Potential for cats to transmit diseases.

• Impacts on hygiene and food safety.

• The risk of non-native species harming local ecosystems if cats escaped at foreign ports.

Modern vessels meet hygiene, pest control, and morale needs with alternative methods, such as climate-controlled spaces, communication technology, and professional pest management.

Frequently Asked Questions About Ship’s Cats

Why did ships need cats? Couldn’t they just use traps?

While ships used other means like traps and poisons, cats were more effective and less hazardous to the crew. Their constant presence and predatory instincts kept rodent populations in check around the clock.

Were there any superstitions about killing or mistreating ship’s cats?

Absolutely. Many sailors thought it was bad luck to harm or throw a cat overboard, believing it would bring storms or disaster to the ship and crew.

Do cats still work on boats?

Occasionally, yes, especially aboard small fishing vessels and private yachts. However, on regulated commercial ships, cats are a rarity.

Can a cat really predict the weather at sea?

Not exactly, but old sailor legends said so. Many believed a cat’s behavior could forecast the weather - washing behind its ears supposedly indicated rain was coming.

What happened if a ship’s cat died at sea?

Crews gave ship’s cats proper “burials at sea,” much as they would for any valued crew member. Some were even honored with commemorative posts or mentions in logs.

Are there any maritime museums or memorials to ship’s cats?

Several maritime museums feature exhibits on ship’s cats, and some ships that have become museums even include stories of their famous feline crew.

Curious about life at sea, maritime careers, or the history of seafaring? Check out more insightful (and entertaining) articles from Martide, including seafarer quotes, fascinating facts about the shipping industry, and facts about maritime and geographical features.

Are You Looking for a Seafarer Job?

The ship’s cat might not be part of a traditional crew onboard a vessel anymore but at Martide we’re always looking to fill plenty of seafarer job vacancies.

Are you looking for Chief Officer jobs, Second Engineer jobs, Master jobs, Fitter jobs, Third Engineer jobs, Ship’s Cook jobs, Second Officer jobs, Oiler jobs or any other rank?

We can help you find your next job on a ship.

Create your free Martide account now and start applying for your next seafarer job right now.

We look forward to seeing you onboard soon. Meanwhile, why not follow us on Facebook, LinkedIn and Twitter / X?

This blog post was originally published on December 28th 2023 and updated on July 29th 2025