I found out that caravans are more useful than I thought.
You see, I has having two problems.
The first was I felt my depot was not well enough protected. Two out of three sieges happened when I had a caravan in the depot and many more thieves have been showing up. So I moved it nearer to my fortress entry and right in among my pastures.
The second was, while I never have enough trees, I have tons of predators. The dingos were wiped out and so were many of the wolves, foxes, and eagles. And they make good eating. But the kea keep coming back. I kill six and six show up next year. Not only did they steal some food but they attack my chickens, my larger livestock, and even killed a cute little baby bunny!
I tried stationing my military in the pastures but only a few kea were killed by this tactic - most just attacked animals on the edges. One or two kea did get killed by my stone traps at my gate - which does not make much sense as they fly...
Anyway, I didn't want my Dwarfs just standing around and decided to replace them.
So I posted some wolves (I got from one of the caravans) in among the chickens and rabbits. It worked - kind of - now the kea started attacking Dwarfs working outside. So I put another wolf near the outside workshops to protect the whiners. "Ouch! A small bird is attacking me!"
I understand if they were Rocs but keas...tsk.
The kea found a weakness in my defense, a hole without wolves, and flew in to get the chickens. But ran right into the human caravan who was visiting my new depot. In less time it takes to type this posting three keas were wiped out by human bowmen.
So humans turn out to be useful after all.
Oh, I also have a windmill sending power to two millstones, two underground greenhouses growing above ground plants, created a bathhouse with a pump, have an outdoor barrack and archery range with a glass blocks in the ceiling so the main unit gets use to sunlight, have a outside bathhouse with some of the wall missing to let in sun, failed to get a waterwheel to work, flooded a room in my fortress for failing to understand water pressure, and I am making a multi-level Grand Hall which already has a working sunroof, and am in the process to creating a below ground area for beekeeping, but that's not as interesting as my war against NATURE!
I will get you, you small winged pests! And your little dog too!
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Hey..that gave me an idea...are there flying monkeys I can train?