as @JoshC says - be prepared to stay out late, till the very last few mins of shootable light. Or very first light in morning. Been my experience in various Haast & Wanaka blocks that the stags only step out of the bush when its almost dark. This pretty much rules out day missions to the tops, take a tent or bivy and stay out there to make best use of last and first light. Then you also need luck on your side to have chosen a good posie where there's a chance of some decent deer around.
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