Aquatic regions are broken down into 6 main areas:

Ice:

Ships can encounter ice floes in freshwater and icebergs in salt, the
latter ranging from single mountains of ice to fields of 10-20 small ice
mountains that continually break against each other and anything that
gets in their way. The chief danger to ships from ice is damage to the hull
damage for every round it is in contact with the ship. In addition,
icebergs a sea have a 10% chance of putting  ahole int he ship (treat as
rammed; see "Ramming" in the DMG).
<FREQUENCY: Common ([Cold Freshwater Surface])>
<FREQUENCY: Rare ([Cold Saltwater Surface])>
<FREQUENCY: Rare ([Cold Saltwater Depths])>
<FREQUENCY: Very rare ([Cold Freshwater Surface])>
<^check all above entries^>

Ghost Ships:

Many ships have been lost at sea and on hidden rivers.
These ships still sail, manned by undead sailors and commanded by the
more powerful of their breed, A ghost ship can be any type of ship from =
galley to warship. On a percentile die, the crew will be: 01-40 = 10-40
skeletons; 41-80 = 10-40 zombies; 81-00 = 10-20 juju zombies. <note: sea zombies would be appro. as well>
    The commanding officers will be: 01-30 = 1-4 wights; 31-40 = wraiths; 61-80 = 1-2 spectres; 81-95 = ghosts; 96-00 = 1 lich.
A ghost ship can be sighted in daylight and at night but will usu. only
attack at night, when the ship's masters are at full power.
    FREQUENCY: Rare ([Cold Freshwater Depths])
    FREQUENCY: Very rare ([Temperate Freshwater Surface])
    FREQUENCY: Rare ([Temperate Saltwater Surface])
    FREQUENCY: Very rare ([Tropical Freshwater Surface])
    FREQUENCY: Rare ([Tropical Saltwater Surface])

<remove deathship.jpg>

Sunken Ships:

These victims of storms, ice, or hostile ships can be any
type of ship. They often still still bear their original merchandise and treasure
and just as often have inhabitants, either new creatures moving in
or remains of the original crew. On a percentile die the inhabitants are as follows:
 

01-20	carries merchant treasure (see "Man, Merchants")
11-20	no treasure
21-60	2-24 lacedons from the original crew
61-00	other monsters (roll on the main chart)

    FREQUENCY: Rare ([Temperate Freshwater Depths])
    FREQUENCY: Rare ([Temperate Saltwater Depths])
    FREQUENCY: Rare ([Tropical Freshwater Depths])
    FREQUENCY: Rare ([Tropical Saltwater Depths])

Floating Seaweed: Floating seaweed is a hazard and sometimes serves
as a lair for creatures like seahags. Any ship entering an AREA of floating
seaweed is slowed by 50%, and there is a 40% chance of its having
another encounter while among the mass of sea plants.
    FREQUENCY: Common ([Temperate Saltwater Surface])
    FREQUENCY: Common ([Tropical Saltwater Surface])

Seaweed Beds: The underwater equivalent of surface seaweed,
these beds are rooted to the sea floor and are from 30-300 feet high.
Vision is reduced to 10 feet in beds of seeweed,
and there is a 30% chance of another encounter in the AREA.
    FREQUENCY: Common ([Cold Freshwater Surface])
    FREQUENCY: Common ([Temperate Saltwater Depths])
    <^move above to floating seaweed?^>
    FREQUENCY: Common ([Tropical Saltwater Surface], [Tropical Saltwater Depths])

Land Encounters: Roll on the appro. table for the terrain nearest
the water. IF not app licable, <THEN> treat as no encounter.
<FREQUENCY: Common ([Cold Freshwater Surface])>
<FREQUENCY: Common ([Cold Saltwater Surface])>

Islands:

Freshwater {game} can be found on islands, as can unfriendly
creatures and tribesmen (treat as land encounter). Islands have surrounding
reefs 10% of the time that do 2-12 points hull damage to ships.
There is a 20% chance they will put a hole in the ship (treat as ramming).

    FREQUENCY: <?> ([Cold Saltwater Surface])
    FREQUENCY: Rare ([Temperate Freshwater Surface])
    FREQUENCY: Uncommon ([Temperate Saltwater Surface])
    FREQUENCY: Rare ([Tropical Freshwater Surface])
    FREQUENCY: Uncommon ([Tropical Saltwater Surface])

Whirlpools:

The whirlpool is a trap for the unwary.
Seventy-five percent can drag down only small craft (50 feet || less),
while 25% can drag any size ship to the bottom.
Ships are dragged into the whirlpool at 1" per
round, cumulative (1" the 1st round, 2" the 2nd, 3" the 3rd). A ship must
size ship to the bottom. Ships are dragged into the whirlpool at 1" per
round, cumulative (1" the 1st round, 2" the 2nd, 3" the 3rd). A ship must
xceed the {SPEED}{SPEED} of the flow to escape. Otherwise, it will be dragged to
the bottom in 6 rounds (see "Afanc" in this vol).
  FREQUENCY: Very rare ([Temperate Freshwater Surface])
  FREQUENCY: Rare ([Temperate Saltwater Surface])
  FREQUENCY: Very rare ([Tropical Freshwater Surface])
  FREQUENCY: Rare ([Tropical Saltwater Surface])
 

<x>
<COLD FRESHWATER DEPTHS>
COMMON: No common
<x>

<octopus was interpreted as 'giant octopus'>
 

COLD FRESHWATER

COLD FRESHWATER Surface

2	Dragon Turtle
3	Harpy
4	Greenhag
5	Naga, Water
6	Lacedons
7	Turtle, Giant Snapper
8	Swan
9	Ice
10	Surface Encounter
11	Man, Merchant
12	Surface Encounter
13	Crystal Ooze or Island
14	Buccaneer
15	Merrow
16	Scrag
17	Nixie
18	Falcon, Large
19	Dragon, Sea
20	Swanmay

COLD Freshwater Depths

2	Giant, Storm
3	Verme
4	Quipper
5	Vodyanoi
6	Sirine
7	Lacedon
8	Kapoacinth
9	Crab, Giant or Scrag
10	Pike, Giant or Nixie
11	Otter or Dragonfish
12	Octopus <Octopus, Giant>  or Sunken Ship
13	Gar, Giant or Nixie
14	Merrow
15	Turtle, Giant Snapping
16	Lamprey, Normal
17	Hippocampus
18	Morkoth
19	Otter, Giant
20	Nereid

COLD SALTWATER

COLD SALTWATER Surface

 

2	Wind Walker
3	Whirlpool
4	Dragon, White
5	Ghost Ship
6	Narwhale
7	Turtle, Giant Sea
8	Sea Lion
9	Man, Merchant
10	Shark
11	Whale -
12	Pirate or Hollyphant
13	Ice
14	Dolphin
15	Island
16	Scrag
17	Will-o-wisp
18	Seawolf, Greater
19	Selkie
20	Dragon Turtle

COLD SALTWATER Depths

2	Verme
3	Water Weird
4	Seawolf, Lesser
5	Urchin, Green
6	Urchin, Red
7	Dolphin
8	Elf, Aquatic
9	Shark
10	Crab, Giant or Nixie
11	Narwhale or Naga, Water
12	<Octopus, Giant> or Shark, Giant
13	Whale
14	Sea Lion
15	Kopoacinth
16	Calamari, Giant <make measurements, to confirm species>
17	<Octopus, Giant>
18	Slime, Green
19	Titan
20	Dragon, Sea

TEMPERATE FRESHWATER

-
 

TEMPERATE FRESHWATER Surface

2	Dragonfly, Giant
3	Dragon, Carp
4	Lizardman
5	Crystal Ooze
6	Buccaneer
7	Merrow
8	Swan
9	Crocodile, Normal
10	Man, Merchant
11	Throat Leech
12	Crane, Giant or Dragon, Mist
13	Surface Encounter
14	Crayfish, Giant
15	Frog, Giant
16	Sirine
17	Otter, Giant
18	Scrag
19	Dragon, Red
20	Boobrie

TEMPERATE FRESHWATER Depths

2	Mud-man
3	Muckdweller
4	Beaver, Giant
5	Lamprey, Giant
6	Lizard Man
7	Turtle, Giant Snapper
8	Kopoacinth
9	Beetle, Giant Water
10	Spider, Giant Water
11	Throat Leech
12	Crocodile
13	Otter, Giant or Nymph
14	Crayfish, Giant
15	Lamprey
16	Dragon, Carp
17	Gar, Giant
18	<Octopus, Giant>
19	Algoid
20	Lizard Man with Lizard King

TEMPERATE SALTWATER

TEMPERATE SALTWATER Surface

 
 

2	Ki-rin
3	Dragon, Cloud
4	Ghost Ship
5	Whirlpool
6	Crabman
7	Eel, Giant
8	Island
9	Dinosaur, Plesiosaur
10	Man, Merchant
11	Shark
12	Whale
13	Seaweed, Floating
14	Dinosaur, Elasmosaur
15	Will-o-wisp
16	Crab, Giant
17	Lacedon
18	Dragon, Bronze
19	Seawolf, Giant
20	Verme

TEMPERATE SALTWATER Depths

2	Morkoth
3	Kraken
4	Narwhale
5	Lamprey, Giant
6	Shark, Giant
7	Sea Lion
8	Urchin, Black
9	Dinosaur, Plesiosaur
10	Sea Horse
11	Shark
12	Whale
13	Seaweed
14	Masher
15	Eel, Giant
16	Dragon Turtle
17	Mottled Worm
18	Seawolf, Lesser
19	Eye of the Deep
20	Titan

TROPICAL AND SUBTROPICAL FRESHWATER

TROPICAL AND SUBTROPICAL FRESHWATER Surface

2	Froghemoth
3	Couatl
4	Catfish, Giant
5	Crystal Ooze
6	Dragon, Mist
7	Spider, Giant Underwater
8	Crayfish, Giant
9	Man, Merchant
10	Land Encounter
11	Crocodile, Normal
12	Throat Leech
13	Behemoth or Crane, Giant
14	Frog, Giant
15	Hippopotamus
16	Sirine
17	Merman
18	Manticore
19	Kelpie
20	Thork

TROPICAL AND SUBTROPICAL FRESHWATER Depths

2	Verme
3	Eel, Weed
4	Kelpie
5	Vodyanoi
6	Behemoth
7	Merman
8	Snapper, Giant
9	Beetle, Giant Water
10	Dinosaur, Dinichtys
11	Spider, Giant Water
12	Throat Leech
13	Dragonfish or Scrag
14	Dinosaur, Archelon
15	Kopoacinth
16	Bunyip
17	Lizardman
18	Dragon, Spirit
19	Sea hag
20	Water Weird

TROPICAL && SUBTROPICAL SALTWATER Surface

2	Wereshark
3	Seawolf, Greater
4	Roc
5	Whirlpool
6	Sahuagin
7	<Giant> Portuguese Man-o-war
8	Sea Hag
9	Crocodile, Giant
10	Dinosaur, Plesiosaur
11	Man, Merchant
12	Shark
13	Whale
14	Man, Pirate
15	Dinosaur, Mosasaur
16	Ghost Ship
17	Shark, Giant
18	Sphinx, Andro-
19	Ixitxachitl
20	Triton

 

TROPICAL AND SUBTROPICAL SALTWATER Depths

2	Morkoth
3	Urchin, Silver
4	Crocodile, Giant
5	<Octopus, Giant>
6	Pungi-ray
7	Sahuagin
8	Urchin, Black
9	Dinosaur, Dinichtys
10	Ray, Sting
11	Shark
12	Seaweed
13	Strangleweed
14	Barracuda
15	Dinosaur, Nothosaur
16	Eel, Electric Marine
17	Triton
18	Wereshark
19	Kraken
20	Ixitxachitl