Nectar Den is a hidden fishing area in Fisch with seven bestiary entries. If your goal is 100 percent completion, the only thing that matters is catching each of those seven fish under the right conditions and making sure you do not miss the hunt-only Exotic.
Quick answer: Nectar Den bestiary completion requires 7 catches: Honey Clump, Honey Drifter, Combscale Bass, Stinger Skipper, Comb Cluster, Bee, and Queen Bee Serpent.

Nectar Den bestiary fish list
| Fish | Rarity | Bait | Weather | Season | Time | Catch note |
|---|---|---|---|---|---|---|
| Honey Clump | Trash | Magnet | Any | Any | Any | Can be caught anywhere inside Nectar Den |
| Honey Drifter | Common | Flakes | Clear | Summer | Day | Can be caught anywhere inside Nectar Den |
| Combscale Bass | Uncommon | Minnow | Any | Summer | Any | Can be caught anywhere inside Nectar Den |
| Stinger Skipper | Unusual | Beetle Grub | Windy | Summer | Any | Can be caught anywhere inside Nectar Den |
| Comb Cluster | Rare | Rapid Catcher | Clear | Summer | Day | Can be caught anywhere inside Nectar Den |
| Bee | Legendary | Super Flakes | Clear | Summer | Day | Can be caught anywhere inside Nectar Den |
| Queen Bee Serpent | Exotic | Truffle Worm | Clear | Summer | Day | Only appears during the Queen Bee Serpent Hunt |
Nectar Den completion trigger
The bestiary completes when all seven entries are filled. Six of them can be caught anywhere inside Nectar Den, while Queen Bee Serpent is the only entry with an extra trigger. If you never catch that Exotic during its hunt, the bestiary does not reach 100 percent.
You know it worked when every fish slot in the Nectar Den bestiary is filled, including the Exotic slot for Queen Bee Serpent. If one entry is still missing, completion has not triggered yet.

Queen Bee Serpent requirement
Queen Bee Serpent is the gate for full completion. The fish is tied to the Queen Bee Serpent Hunt and uses Truffle Worm under Clear weather, Summer, and Day conditions.
If you are trying to verify why the bestiary is still incomplete, this is the first entry to check. Secret fish are not required for Nectar Den completion, but Queen Bee Serpent is.

Nectar Den access requirement
Nectar Den sits beyond Verdant Pocket. To reach it, go through Lost Jungle, buy the Gas Mask near Oliver at (-2975, 143, -2162), move through Toxic Cave to Toxic Grove, cross with the Toxic Proof Raft, and continue into Living Garden.
From there, head to the Koi Nectar pool at (-2251, -321, -3022). A hidden opening leads into Verdant Pocket, and another hidden opening at the far end leads into Nectar Den.

Nectar Den survival condition
Nectar Den is unsafe if you enter without protection from the bees. The two reliable ways to avoid damage are the Pollination Buff or the Sweet Stinger Rod.
The Pollination Buff comes from opening flowers around the Living Garden. With that buff active, the bees in Nectar Den stop attacking you for a short time. The Sweet Stinger Rod also prevents damage inside the area.
Nectar Den bestiary constraints
Most of the bestiary is built around Summer, and several of the higher-value catches also require Clear weather and Day. Honey Clump has no condition lock, which makes it the easiest entry to clear early.
Combscale Bass only needs Summer. Stinger Skipper adds Windy weather. Honey Drifter, Comb Cluster, Bee, and Queen Bee Serpent are stricter, all leaning on Clear Summer Day windows.

Nectar Den completion time
A full Nectar Den clear usually takes around two to three hours. You do not need a Reinforced Rod or Invincible Enchantment to finish the area.
If you are checking whether your setup is sufficient, the main blocker is not a special immunity rod for fishing itself. The real completion checks are access to Nectar Den, staying alive in the area, and landing Queen Bee Serpent during the hunt.
Nectar Den is a compact bestiary with a simple rule set: six fish can be caught anywhere in the zone, one fish is hunt-locked, and 100 percent completion happens only when all seven entries are filled.