Years ago when I recently graduated a Welsh Uruguayan and I went to
work on the Tennessee Tombigbee Canal system (we had both graduated
together) with William Hampton Adams in Columbus, Mississippi (home of
Tennessee Williams) and tried to see some of the sites on the way
there (Russel Cave in Alabama, the site of David Crockett's birthplace
near Limestone Tennessee, G. Washington's "lifeguard" (bodyguard) ?
McCrory grave site) and stopped at Moundville, Alabama. There was a
screen and obviously there were archaeologists screening over the bank
of the Black Warrior River, where the drainage ditches from the mound
complexes went over the steep bank into the river. We decided to look
around following some of the pathways. One small mound, uncleared of
vegetation I thought to walk up to the top of and look at. On it was a
slab of thick aluminum with a single name (not Bobby-Joe or Sally-Mae,
nothing like that painting of Southern names in the Birmingham Art
Museum has, quite empty one Sunday) etched or carved into it. I assume
it was the grave of a caretaker's or former owner's pet, most likely a
canine. Anyone here know?

We have a NY State registered historic pet cemetery (quite small) on
Conscience Bay I think in Setauket, NY. One enigmatic place "The Black
Duck Lodge" used in the 19th century by apparently some people of
repute in Flanders, NY out on Long Island, now a County Park, with an
early Hubbard family site on it had two dog headstones near the water
where "duck blinds" were, where it is known any ducks removed were
replaced by the caretaker(s) who kept daily weather records in the
19th century. There is also a large pet cemetery in Scarsdale, NY.