Its over 4000.sav
What: Converting a system from hunting ground to colony with the super-coloniser leaves the system with -450 food per pop.

How:

I played Vaulters for the first time. Using "Pirate" fleets with their Corsairs special factional ability, I attacked a UE AI's home system, "occupied" it, which turned it into a pirate hunting ground, and then, 4 turns later, instantly colonized it with the Argosy. 

Everything looked fine, the system was inexplicably ecstatic, I had food production, and there were some Yuusho that I wanted one of. Yet, next turn, 1 pop lost. Turns out the pop loss from the hunting grounds is still on, with a massive negative food stock. 

Screenshot:

Further Info: 

The Current stock raises by 450 for each pop I transfer to the spaceport. I can move the pops back onto the planets afterwards. This effect is limited to the amount of slots the spaceport has; In my example, I could remove 1250 food debt, give or take, per turn, though this seems to invalidate the actual "growth" from food production.