"The scream came from the front of the group. About 25m ahead of me..."
If you’re heading out hiking or tramping during the New Zealand summer and early autumn months, especially in beech forests (and especially at the top of the South Island) you’re almost certainly going to encounter wasps. Their sting can be at best painful, at worst trigger an anaphylactic reaction. Here's a few tips on how to avoid wasps nests and how to treat the stings should the worst happen.
Beware the sting: A Tramper's Guide to Avoiding and Managing Wasp Attacks