Any Water Source

While some Sea Creatures require specific location to be fished up, there are several which do not require this, and as such they can be spawned on all islands

Requirements	Name	Rarity	Chance	Level	❤ HP	Drops	XP Yield	Chat Message
Fishing Level 1	Squid	COMMON	24.56%	1	2000	Lily Pad  Ink Sac	+41	A Squid appeared.
Fishing Level 2	Sea Walker	COMMON	16.31%	4	1500	Lily Pad  Raw Fish  Rotten Flesh	+68	You caught a Sea Walker.
Fishing Level 3  Dark Bait Nighttime (7:00pm – 6:00am) or in The Park	Night Squid	COMMON	17.83%	6	4000	Ink Sac  UNCOMMON Fishing Exp Boost  Lily Pad  Squid Boots  RARE Fishing Exp Boost	+270	Pitch Darkness reveals you've caught a Night Squid.
Fishing Level 5	Sea Guardian	COMMON	12.23%	10	2500	Lily Pad  Prismarine Crystals  Prismarine Shard  Sea Lantern	+101	You stumbled upon a Sea Guardian.
Fishing Level 7	Sea Witch	UNCOMMON	14.27%	15	6,000	Clownfish  Lily Pad  Raw Salmon  Fairy Armor	+338	It looks like you've disrupted the Sea Witch's brewing session. Watch out, she's furious!
Fishing Level 9	Sea Archer	UNCOMMON	11.21%	15	7,000	Bone  Lily Pad  Raw Fish  Enchanted Bone  Bone Dye	+169	You reeled in a Sea Archer.
Fishing Level 11	Rider of the Deep	UNCOMMON	8.15%	20	20,000	Dark Bait  Lily Pad  Sponge  Enchanted Book (Magnet VI)  Enchanted Feather  Enchanted Rotten Flesh	+270	The Monster of The Deep emerges from the dark depths...
Fishing Level 13	Catfish	RARE	5.1%	23	26,000	Clownfish  Lily Pad  Pufferfish  Raw Fish  Raw Salmon  Sponge  Enchanted Book (Frail VI)	+405	Huh? A Catfish!
Fishing Level 16	Sea Leech	RARE	3.26%	30	60,000	Clownfish  Lily Pad  Raw Fish  Sponge  Enchanted Book (Spiked Hook VI)  RARE Fishing Exp Boost  EPIC Fishing Exp Boost	+675	Gross! A Sea Leech!
Fishing Level 17	Guardian Defender	EPIC	2.65%	45	76000	Lily Pad  Raw Fish  Sponge  Enchanted Book (Lure VI)  Enchanted Prismarine Crystals  Enchanted Prismarine Shard	+1,013	You've discovered a Guardian Defender of the sea.
Fishing Level 18	Deep Sea Protector	EPIC	1.79%	60	150,000	Clownfish  Lily Pad  Sponge  Enchanted Book (Angler VI)  Enchanted Iron  EPIC Fishing Exp Boost	+1,350	You have awoken the Deep Sea Protector, prepare for a battle!
Fishing Level 19	Water Hydra	LEGENDARY	0.37%	100	500,000	Clownfish  Lily Pad  Pufferfish  Raw Fish  Raw Salmon  Sponge  Enchanted Book (Luck of the Sea VI)  Fish Affinity Talisman  EPIC Fishing Exp Boost  Water Hydra Head	+4,050	The Water Hydra has come to test your Strength.
Fishing Level 20	Sea Emperor	LEGENDARY	0.2%	150	750,000	Lily Pad  Raw Fish  Sponge  Enchanted Book (Blessing VI)  Enchanted Lily Pad  Enchanted Prismarine Crystals  Enchanted Prismarine Shard  Bobbin' Scriptures  Emperor's Skull  RARE Flying Fish Pet  EPIC Fishing Exp Boost  EPIC Flying Fish Pet  LEGENDARY Flying Fish Pet  Shredder	+3,375	The Sea Emperor arises from the depths...