Waitete Bay on the Coromandel grew the biggest oysters ever.

Oysters around here grew exceptionally large and were plentiful when waters were warm and pollution free.

Humans pollute and they don’t tidy up properly. Poorly maintained waste treatment is a huge issue for oyster farmers. We can’t remove humans but we should remove our wastes before we discharge effluent in the ocean. Oysters were living in these waters long before humans arrived.

The coast that existed 35 million years ago was low lying.

The point at the North end of the bay, where this picture was taken, is made of hard limestone. A shell bank grew on the ocean floor between 30 and 25 million years ago. A few pieces of coral discovered here indicate the water was 5 degrees warmer than today. By 25 million years the ago the shells had cemented together under the weight of half a kilometre of overlying rocks to form a hard limestone.

Two large fossil oysters, travelling through time and space in a lump of hard limestone were on view. Often buried by shifting sands, a recent storm uncovered these giants.

The fossil oysters can be more than 10cm thick.

A closer look.