Salmon extinct but still showing a population?

[Lazuli]

We run a small private server and while some of us were playing we got an achievement stating salmon had gone extinct. Contrary to this our server stats say there are 62 and that number hasn't changed since day 2. Anyone know what is happening?

[Acefirebat]

Happened to us too, but with trout. Following for updates.

[ShadowDragonOfTheNorth]

Are they being over fished and not able to reproduce?

[$tump]

Sounds like Mutant Fish?
No idea the cause. How does pollution work neways?
Maybe you're polluting more then reproduction rate for 62 so they're just dead?
Or perhaps they swam into the ocean and are just waiting to die?

[SLG-Dennis]

Extinction achievements triggering despite species not being extinct is a known bug.

[DownyGecko07]

I pretend its their eggs hatching and repopulating lol