Sometimes, my butchers are lazy. Dwarven Caravan arrives, disturbing a pack of vultures. One gets chased into the fortress, corners a miner, and gets an iron pick in its head for its trouble. The other one gets shot down by the caravan guards.
My butcher only touches the corpse generated by his miner buddy. The other vulture is sitting in the refuse stockpile, a scant 12 spaces from the butchery. "Butcher a dead animal" is throwing back error messages about their not being a valid butcherable corpse.
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Another fort.
Bloody unicorns. I send out my military to punch the prancing buggers to death. It works. The unicorns are brought back to the fort. The butcher handles them fine.
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Another fort
Embark next to a family of raccoons. Immediately draft the woodcutter to chase down and murdilate the three things. He is successful, and 3 mangled raccoons are brought to the refuse pile. The butcher handles exactly two of the raccoons, and refuses to touch the last corpse, slowly rotting in the refuse pile.
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Another fort
Buzzard gets cornered into the fort, and a civilian manages to break its wing in their panic. I send the military in to finish it off. Bam. Buzzard Meat Biscuits for everyone.
Then, a Nightwing attacks. The military is called up again. They murdilate him. The nightwing is brought back to the refuse pile. "nuh-unh" says the butcher. The nightwing rots.
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Am I missing some essential step in butchering animals? Sometimes my butcher has no trouble finding the corpse. Other times, they find the corpse after queuing the "butcher a dead animal" several times. In other instances, they can't find it at all.
The corpse has *never* been forbidden. "Dwarves gather refuse from outside" has been turned on in all applicable cases. Is anyone else running into this? Am I doing something wrong?