Cape Foulwind is a conservation area toward the northern end of the West Coast of the South Island. It's main feature is a breeding colony for the New Zeland Fur Seal, which is well worth a look, since you get an excellent view of the nursery area from the viewing platforms on the cliff above it.
The real highlight of the trip for me, however, was finding that a large number of Weka inhabit the bush and scrub around the conservation area. Weka are one of New Zealand's many flightles birds, and, like most have been hard hit by the arrival of land mammals in general and humans in particular. Maori regarded them as good eating, and European settlers regarded them as a pest due to their intelligent, inquisitive nature.
Weka haven't done as badly as they could have, however; all four sub-species still exist, although the North and South Island variants are confined to a few small areas. They're lively birds who think nothing of running into houses and making off with food or bright, shiny objects. They're omnivourous, and are happy to eat other birds' chicks, including chickens, snails, slugs, and will attack and kill some of the introduced mammals who normally prey on birds - in particular, they actively hunt and eat rats. Ideal to have around the garden, really, as long as you don't mind losing strawberries to them.
I've only ever seen a Weka once before, in the area around Tiwai Point in the extreme south of the Island, and that was only from a car window as it ran into the bush, so the change to get close to over half a dozen of them was neat.
The Weka's curiousity and impudence was definitely on display - these ones are basically unafraid of humans. Well after the Weka themselves appeared, there was a DOC notice asking people not to feed them (oops!), but I'm happy to have had a good look at them.