Niue is located on the Pacific sea plate that moves steadily at about 1cm per year in a NW direction. That may not seem much, but when Niue was still an active volcano some 2-3 million years ago, it was located some 2 million centimeters further South-East - so 20km! Niue is moving slowly towards the Kermandec trench and eventually in the future, it will be swallowed up by the Kermadec trench and pushed underneath the Indian-Australian plate. No need to rush and get your flights booked for next week just yet; however, it explains why so few islands exist east of the Kermadec Trench, which leaves Niue rather alone in this area of the Pacific.
The interior of Niue is rugged and rocky, descending to a coastline that is often lined with steep cliffs; some parts of the coast are fringed by narrow coral reefs. Most of these reef flats have easy access and attracts tourist and locals alike. The tourists love it because of the marine life and the exploration of something new, while the local people use the reef as a source of food.
The diagram shows the general cross section of the shore line. From right to left, one leaves the ancient Mutalau Lagoon of 30-40m height, crossing the ancient Mutalau Reef of 45-75m to descend onto the Alofi Terrace of 20-27m height. Descending over one of the ridges, one comes to a steep dropoff of 6-20m height, undercut by a wave-cut notch of several metres high. Going down one arrives at the reef flat which is bordered by a slightly higher fringing reef.
The reef flat is composed of three kinds of limestone: reef rock, beach conglomerate and cemented or loose coral sand. Corals are the highly visible structures on a coral reef rock and when the coral inside die, a hard porous limestone remains. The coralline algae grow like a pink paste or paint. When coral build the reef rock, coral fragments are visible. On the other hand, when the reef rock is built by corraline algae, the visible fragments are almost completely absent. Underneath the reef flats there is a maze of caves, at times opening up into blow holes and canyons. At about 6-12m the rubble collects onto sandy flats, alternated by coral-clad ridges, leading down a gentle slope to 25-30m depth where the slope becomes steeper, the deep reef with corals able to live in diminished light, while unaffected by storm waves.
You will find Tautu beach on the east coast off the island, at the end of Liku sea track near the village of Liku. To access Liku sea track, you have take any road to the village of Liku, and when you get there you'll see a very long white construction just beside the road, with a large grassy area behind. At the left side of this building you'll find the entrance to a small gravel road that runs over the grass until the end. Just follow this gravel road and you'll see the sign to Liku sea track. It is a little tricky to find the track at first!
WARNING: Plan to attempt this cache at low tide – at high tide you will not be able to descend onto the reef flat through the cave. Information on the tides can be obtained form the visitor information centre in Alofi.
Logging requirements: As you walk onto the reef flat, examine the composition of the reef rock below your feet. Based on the information above and your observations, do you think the reef rock here was built mostly by coralline algae or coral? Do not post answer in your log!! Email the owner with your answer. No need to wait for confirmation, feel free to log your visit. However, logs without sufficient evidence will be removed.
Some of the information obtained from http://www.niuetotal.com and http://www.seafriends.org.nz.
I hope you enjoy this paradise on earth, and get a chance to visit the other caches on the island as well.