SOUTH ISLAND OYSTERCATCHER (Haematopus finschi) – (See images below)
The South Island (pied) oystercatcher, in spite of its name, can also be found on the North Island after its breeding season. It measures about 18 inches long, and its underside is white while the back and head are black. It is common and endemic to New Zealand. As the name implies, oystercatchers eat shellfish, which they pry open with their specialized bill, which they will also use to hammer the shells. Humans need a special knife to pry open oysters, and even then it takes some strength. One can only imagine how a small bird can achieve the same feat!

South Island oystercatcher, Cape Reinga, NZ - by Denise Motard, Feb. 2013
South Island oystercatcher, Cape Reinga, NZ
This individual was seen on the shore of the Kaikoura Peninsula. It is amazing that Nature provides a bird with such a powerful bill.
South Island oystercatcher, NZ