I have some captured animals from cage traps like giant dingos and goblins. If I hit "b" and "j" only the goblin cage shows up (besides for all empty cages). The dingos are chilling in the animal stockpile. Why is this happening?
When you say you pressed b -> j I assume you also pressed 'x' to load out the specific list? If not, definitely try that.
There are plenty of reasons the cages might not be showing up in your build list, I would suggest you try the following, if you haven't already:
Check that the cages are not forbidden
- Pretty self explanatory, you may have accidentally forbidden them somewhere along the way, in which case you cannot use them for construction until you reclaim them, loo(k) at the cages to see if they have the forbidden tag, if they do, un(f)orbid them.
Make sure they aren't the object of another task, such as a hauling labor
- Your dwarves may have these queued up as a hauling job, even if they aren't carrying them right now. Try pausing the game and forbidding all of the cages, then briefly unpausing and repausing the game. Then go back and unforbid (reclaim) them, and without pausing, try to build your cages - they should show up in the list now.
Just a reminder, you can forbid/reclaim an area of items (i.e. your stockpile of cages) by using the designations menu. (d -> b -> f for forbidding, d -> b -> c for reclaiming)
If neither of these work for you, let me know and we can try some other things.