Animal traps - looking for information

Does anyone know how traps exactly work?

I have currently 12 hunter lodges, each one setup for 2 traps to get hides. I checked every single one of them and they all produced 0 traps the previous year.

Does that mean they build the traps once and that’s it, they re-use it? Or do you know how often they need to be replaced/use iron.

I am trying to find out / cut iron spending somewhere because right now between tools and barrels, despite of having 32 miners non stop gathering iron ore and 16 people working at the smeltery my stock is decreasing at a super fast rate and I have no more people to put to work on a new mine or smeltery.

I thought maybe getting rid of the traps? I really have not seen an increase of hides since I set this up.