Can catch in Ahrmo Sea with harpoon.

Caught in the deep sea near Randis Island. Affiliated Node: Randis Island

A Skilled Fisherman Quest Note:
Was the first shark I caught here, and I went 2 for 2 when catching a shark species here. I've been able to catch all 4 sharks with one green harpoon for 'A skilled fisherman' by moving around to this location. The 'Tiger Shark' aka Galeocerdo Cuvier is easily caught off Daton Island deep sea, near the area highlighted by the quest. My harpoon was at 4/30 uses left when I turned in the sharks to the NPC.

Can catch in Epheria Sea.

Can catch in Zenato Sea.

Pesca com Arpão entre as ilhas de Teste e Ilha de Daton ao Norte de Epheria
https://prntscr.com/rtrwq4

As of september 2022, can catch the whale shark (Tiburón Ballena in spanish) along as the tiger shark (Tiburón Tigre) on the zone marked by the level 37 fishing quest, north of Epheria, just right south of Eberdeen, Dunde and Albresser islands. It just takes like 60-90 minutes of harpooning. Bring at least 5-6 harpoons, your Fishing Boat (only this type of boat works for harpooning), and a lot of patience.

Словила на гарпун (С него можно рыбачить, только рыбацкой лодке) между островом Овэн и островом Дэйтан.