Inspired by the first comment here, and considering they are called "boats", do flying boats (or seaplanes) carry anchors?
I can confirm they had one: I was lucky enough to own an HU-16 Albatross, many years ago. Prior to my purchase the bird was down in Arizona, near the Davis-Monthan boneyard.
It still had the original Grumman issues anchor mounted in forward compartment. What I don't remember is what material it was fabricated from: I think it was aluminum, and remember thinking of it being novel.. but it may have been bronze.
Either way, they definitely came originally equipped with one.
-- The Albatross, though underpowered, was an amazingly durable bird. Some compelling stories float around about them rescuing downed pilots in Korea and Vietnam, landing in tiny creeks and ripping the floats off on banks.
Fun fact: An albatross that had struck a submerged log and had the bottom ripped out was sent to Australia for repair.. At the facility they didn't have the correct rivets (flush head, chamfered) and so they used normal button head rivets for the repair job... After this repair, it was discovered that this Albatross was able to get off the water at lower speeds than production birds..
It was so much improved that it was sent to Pax River for study.. It turns out that the use of button head rivets enabled it to break the water stiction at very low speeds. The Navy (and Chairforce) then had custom rivets made and replaced all HU-16 lower hull rivets with them. They were custom because they had that chamfer.. So if you look at an Albatross rivet you will see that unique button-head with flush chamfer profile.
For pre-flight, the FAA says:
Check that necessary marine and safety equipment, such as life vests, lines (ropes), anchors, and paddles are present, in good condition, and stowed correctly.
(wikimedia.org) Nose access on the Albatross.
The answer seems yes.