Pokémon Ruby and Sapphire/The Shoal Cave

The Shoal Cave is located just outside of Mossdeep City.

Depending on the time of day there is high tide and low tide. You can confirm the schedule by speaking with Sailor Ernest from Route 125.

Pokemon Found

High Tide

All Rooms

Pokémon found (cave)

Sapphire	Encounter Rate	Ruby	Encounter Rate	Emerald	Encounter Rate
Spheal	50%	Spheal	50%	Spheal	50%
Zubat	45%	Zubat	45%	Zubat	45%
Golbat	5%	Golbat	5%	Golbat	5%

Pokémon found (Surfing)

Sapphire	Encounter Rate	Ruby	Encounter Rate	Emerald	Encounter Rate
Tentacool	60%	Tentacool	60%	Tentacool	60%
Zubat	30%	Zubat	30%	Zubat	30%
Spheal	10%	Spheal	10%	Spheal	10%

Pokémon found (Fishing)

Sapphire	Encounter Rate	Ruby	Encounter Rate	Emerald	Encounter Rate
Old Rod
Magikarp	70%	Magikarp	70%	Magikarp	70%
Tentacool	30%	Tentacool	30%	Tentacool	30%
Good Rod
Magikarp	60%	Magikarp	60%	Magikarp	60%
Tentacool	20%	Tentacool	20%	Tentacool	20%
Wailmer	20%	Wailmer	20%	Wailmer	20%
Super Rod
Wailmer	100%	Wailmer	100%	Wailmer	100%

Low Tide

1F-1,1F-2,BF-1, BF-2

Pokémon found (cave)

Sapphire	Encounter Rate	Ruby	Encounter Rate	Emerald	Encounter Rate
Spheal	50%	Spheal	50%	Spheal	50%
Zubat	45%	Zubat	45%	Zubat	45%
Golbat	5%	Golbat	5%	Golbat	5%

BF-3

Pokémon found (cave)

Sapphire	Encounter Rate	Ruby	Encounter Rate	Emerald	Encounter Rate
Spheal	45%	Spheal	45%	Spheal	45%
Zubat	40%	Zubat	40%	Zubat	40%
Snorunt	10%	Snorunt	10%	Snorunt	10%
Golbat	5%	Golbat	5%	Golbat	5%

Shell Bell

If you collect 4 Shoal Shells from high tide and 4 Shoal Salts from low tide, a man will give you a Shell bell for those, it will restore your HP by 1/8 of the damage you dealt to the opponent.