Several years ago during a boat trip to the Poor Knights Islands
I asked a Whangarei local, Warren Farrelly, about good options
for shore diving. He told me about a site, near Whangarei Heads, called Reotahi, where abundant underwater wildlife, big and small could be found. It was easy to locate on the map, at the bottleneck in the harbour about 30 kms by road from the town basin. The setting is beautiful; sandwiched between the hills of the Whangarei Heads and the harbour.
The hum of machinery and vehicles draws oneâs attention to the giant Marsden Point refinery on the opposite shore. It is a popular spot for boaties; arrive there on any weekend and you might see a string of boat trailers parked alongside the beach. Approximately 100 metres from the nearest headland is a small island called Motukaroro (Passage Island). There is good reason for wildlife abundance at Reotahi. The site has some very strong tidal currents. It is these currents that transport food and nutrients between upper harbour and ocean to Reotahiâs inhabitants. The same currents can be challenging and dangerous for the inexperienced and unprepared.
On our first visit we wandered alongside the eastern up-harbour end of the beach on a grassy track that wended its way across a small rise to a stony bay. The calm waters of the little bay were a welcome relief to my tired body after trudging the (approximately) 200 metres from car to beach with full dive gear on and camera in hand. We passed rocks and patches of kelp as we swam from shore in the island direction. As the water deepened I felt the tug of a strong outgoing tidal current. This was the edge of the channel. Further progress was made by slowly crabbing our way along the sea bottom which was covered in a densely packed field of white anemones. Every now and then we passed a small reef in the channel decorated by long fingery sponges that were pushed over by the flowing water and vibrating like trees in a very strong wind. In fact, it was the sponge life that really impressed on this first visit. These currents are beneficial for the filter feeders.
On subsequent visits we have spent much of our time in the shallows close to shore searching for sea horses and pipefish to photograph. They are very hard to find and blend in almost perfectly with the surrounding weed. If a horse is found it is important to remain still and move slowly. Otherwise the creature will retreat deeper into the weed and will not be seen again. There is plenty of life in the shallows. Nudibranchs, blennies and triplefins are abundant. In between the patches of weed one will sometimes find very large short tail rays or eagle rays. There are also large schools of fish including parore, some up to a half a metre long. Fish large and small are generally abundant.
The strong currents and their eddies in the channel can produce some unexpected results. On one occasion my buddy and I attempted to swim with full gear and cameras across to Motukaroro. We departed the beach only about seven metres apart. I made it across to the island but my buddy, a stronger swimmer than me, was caught in a strong eddy and could not make progress against the flow. The eddies are never gone â even on a slack tide. Boat traffic in the channel can pose a threat to divers and snorkellers. I have witnessed boats speeding up the channel far in excess of the five knot speed restriction. Warren wisely uses a kayak to cross to the island.
A dive from Motukaroro island is very rewarding. On its western side where the depth can reach 30 metres there is a large community of jewel anemones and a vast array of sponges. Warren told me that he sometimes sees bronze whaler sharks over there. Once while photographing a crab he heard some squealing. At first he thought that his ears were malfunctioning. Then he turned to face four curious orca, watching him with his camera.
In October 2006 some of the coastal water east of Reotahi including Motukaroro island was incorporated into the new Whangarei Harbour marine reserve. The reserve also includes some mangrove swamp closer to Whangarei near the suburb of Onerahi. According to the Conservation website, the combined area of both sites is approximately 254 hectares or 2.54% of the Whangarei Harbour1. The application process took about 10 years and was spearheaded by successive classes of seventh formers at Kamo High School. Warren, their Environmental Studies and Geography teacher, told me that it began, in the early 1990s as a Senior project in the schoolâs geography programme. He emphasized to me that the âstudents did all the workâ.
Reotahiâs natural beauty and bounty of underwater life provides a rewarding dive experience. But the strong tidal flows that give the location its vibrancy are challenging for the diver. Diving, particularly near the channel and off the island requires experience, planning, attention to diving safety procedures, and good fitness.