Use the Sturdy Rope to capture 6 Bloodfen Raptors or Bloodfen Screechers.
The patch of swamp to the northeast is home to a particularly nasty breed of raptors. We've lost more than one unwary soldier to them, but I think we can turn them against our Grimtotem neighbors.
Take this rope and use it to capture Bloodfen raptors or Bloodfen screechers that you've subdued. I wouldn't try to capture one of the beasts until you've weakened them quite a bit in combat. It's going to be quite a struggle.