Just curious. Can the captain or officers on US naval vessels have pets?
Given the risk of disease, I doubt that Shipwreck would have been allowed to keep his parrot.
Yo Joe.
Makes me wonder how Captain Archer got away with taking his dog with him on theEnterprise.
Somebody’s been watching Crimson Tide.
Cats were allowed at least as recently as World War II. That link doesn’t indicate whether they’re still permitted today on US ships; it does say that they’ve since been banned from British ships.
Oh, and apparently dogs, cats, and birds have historically been permitted on ships of the Coast Guard. That page also has a photograph of a horse, which I assume was simply a mascot and not actually living aboard a ship. 
No, pets are not allowed and I have never heard of anyone ever actually being allowed to have a pet. When I was on a ship there was a guy who had a sugar glider as a pet. He had to get rid of it as they are not allowed.
But, I have an actual instruction for you that outlines this:
OPNAVINST 3120.32C Section 510.44 on Page 5-19
It basically states that without approval from the CO no pet is allowed. So, yes, there is some bizarre chance that you could have a pet put that’s there for the CO to further disallow pets. Some shore commands such as an air base may specifically not allow anyone to have any pets because its an air base. Or, a single bachelor living in the barracks may not be allwoed pets but a couple living in base housing may be allowed to have pets, etc.
But, oh, I just remembered that someone ran a request to have a pet rock while in the barracks, and, he got approval!
A working animal such as a K9 would be an exception but I just asked someone who did a lot of boarding with the Coast Guard overseas and he never saw or heard of a K9 unit being on a ship.
eb
I’ve seen K9 units on several movie ships (Star Trek IV, Final Countdown), FWIW…
So the CO could have a pet, yes?
Closest I ever saw were strays that had been unofficially adopted by shore commands. I never saw a pet on a ship.
The example that comes to mind is a three-legged beagle that used to hang around EOD in Sigonella in the 1990s. The EOD sailors loved that dog. I think there was some black humor involved there - EOD being so involved in munitions disposal, they would be drawn to an animal with a missing leg.
They named him Tripod, which didn’t take much imagination, admittedly.
It’s good to be the king, er, captain.
And let us not forget: Spot | Memory Alpha | Fandom
Yes, the CO could have a pet if he wanted too according to that instruction manual but that manual is also somewhat of a general/guideline type thing. There are many, many, manuals like this in the Navy. Sometimes covering the same topics and sometimes not. I’ll look and ask around as there may be a health/medical related manual or instruction that may specifically state no pets on a ship. Or, that could be the only mention of it!
Due to the close-knit nature of a ship and the related health/sanitary implications I really could not see an animal, for the sake of being a pet, to be allowed on a ship. There are enough problems alone with humans.
eb
A fine historical documentary, indeed.
Yes, but the Enterprise-D had families on board, as well. It was considered good for overall morale for officers to be able to have their families and pets aboard with them. The ship was built to accommodate them. When the NCC-1701D was destroyed and replaced by the Sovereign-class E, Picard apparently gave him (and probably any other of his senior staff who wished to retain their pets) permission as one of his most senior and trusted officers to keep Spot aboard the new ship. And of course, once Data died, Spot uh…sort of “adopted” Worf as her new master. And Spot never left the ship and accompanied Data on first-contact missions.
However, “Enterprise” took place 200 years earlier as Earth’s space fleet was being launched and the NX-01 was the first of her kind. It seems to me that first-contact protocols with alien races would call for strict quarantine procedures in effect so that animals like Porthos would not transmit any otherwise harmless Earth bacteria to native fauna and cause an ecological disaster.
Sorry for the hijack. 
I know I’m geeking out a little and straying into Cafe Society territory. But the question has been answered now, so I hope a little digression is tolerated.
My assistant, who was in the Coast Guard for 20 years, says captains would sometimes allow “ship mascots.” He also adds that dogs are prone to seasickness…
The remarkable story of Unsinkable Sam - ship’s cat on three vessels - Bismarck, Cossack and Ark Royal.
Cats on a ship probably wouldn’t be pets per se, but working animals keeping down the inevitable rat population.
Are pets allowed on US naval ships?
Sailors Taking Women On Ships As Stowaways
Help me train my pig.
Worst sequential threads ever.
Never having been to Viet Nam myself, I can only echo the statements of many Army 'Nam vets that it wasn’t all that uncommon to have a dog names Tripod as the company/battery/regiment/whatever pet.
Three-legged dogs were not that uncommon, unfortunately.
I’ve read memoirs of a US Navy submarine captain in WWII Pacific where he reports that the crew adopted a dockside cat, and took it along on voyages of the submarine. Sort of unofficial, except that he & all the other officers knew about it, and basically allowed it to happen. I suppose in wartime, anything that improves the morale of your crew is acceptable. And a cat might do worthwhile duty catching mice on the ship.