I would not use poultry shears for killing. Although they are great for butchering and cutting through bone they don't cut though skin very well. Loppers are good if there are two people, but not so much with just one, because it's rather difficult to keep control of the long handled tool and position the head/neck properly at the same time. What I've found to be best for one smallish person is non ratcheting PVC cutters as I can easily handle them with one hand. One good squeeze and it's done. This is the one I use.
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