How to Fish Island 4 Guide: Tuna, Giant Bird & Island 5
Complete Island 4 in How to Fish: catch Tuna with the Professional Boss Lure, place it on grass, beat the Giant Bird, and return the Bird Head.
Quick answer
The tested Island 4 story chain is Professional Boss Lure → Tuna → place Tuna on the grass → Giant Bird → Bird Head → Island 5. The casino is useful for money / achievements, but it is not the story requirement that opens the volcano island.
Step 1: catch Tuna
Use the Professional Boss Lure for the Tuna step shown in the supplied walkthroughs. The Tuna itself can be dangerous, so do not assume the bait phase is risk-free.
Keep the Tuna after the fight / catch; it is needed for the next trigger.
Step 2: place the Tuna on the grass
The quest specifically points the player toward using Tuna as bait for the enormous bird. Video-tested: place the Tuna on the grass rather than leaving it in the water or carrying it around indefinitely.
That action brings the Giant Bird into the encounter.
Step 3: beat the Giant Bird
The bird’s dive-bomb movement is the main problem. It changes altitude quickly, making tracking difficult. Long-range options help because the target spends much of the fight above or away from you.
Buildings / terrain can also create easier sight lines on the dive path. One launch multiplayer session reported the encounter glitching for some players, so if the bird becomes impossible to interact with, rejoining may be more sensible than inventing a missing quest step.
Full combat details: Giant Bird boss guide.
Step 4: secure the Bird Head
After the boss dies, keep the Bird Head. Do not sell or gamble it as if it were ordinary loot.
Video-tested: the Bird Head hand-in is the step that gives access / coordinates for Island 5, the volcano expedition.
What about the casino?
Island 4 also contains the Lucky Bait Casino. The Roulette mechanic can increase an item’s sale value on a win or destroy the item on a loss. It is useful for achievements and money experiments, but it is optional for main-story progression.
Read the Casino & Roulette guide separately.
Island 4 stuck checklist
- No Tuna? Verify you are using the Professional Boss Lure for this story step.
- Have Tuna but no bird? Put the Tuna on the grass.
- Bird dead but no next island? Find and return the Bird Head.
- Bird appears bugged? Treat reload / rejoin as a launch workaround, not an official fix.
Next: Whale boss · Magma Whale final boss · All Bosses
Evidence & source notes
- Official Steam store page — Official identity, release, feature set and the quest/boss island progression loop.
- Launch-day gameplay transcripts supplied for this guide — Quest steps and combat observations below come from supplied launch-window gameplay transcripts and are labelled Video-tested or Needs confirmation as appropriate.