Summer Series week 5: Life's a beach


Many Kiwis have a favourite seaside spot they escape to in the summer and scientists are no exception. In our latest Summer Series feature, six scientists reveal their favourite summer getaway beaches and reflect on how they're changing.

 Dr Ken Grange, Regional Manager (Nelson)
Beach: Rarawa Beach, east coast Far North

Dr Ken Grange
How long have you been holidaying there?

Forty years plus.

What do you enjoy about it?

Rarawa Beach has many attractions for a scientist. It has pure white quartz sand so clean that it squeaks when you walk on it. The water is very clear and blue. At the northern end of the beach there are outcrops of pillar larva and clear rockpools for kids to explore. If you know where to look, behind the large sand dunes there are large areas of rocks that used to form an offshore reef that was tossed ashore in a large tsunami, perhaps 5000 years ago.

What makes this location interesting scientifically?

It is very close to North Cape, so regularly receives warm water currents from further north. In storms, subtropical species wash ashore. These can include coconuts and nautilus shells, making the beach a beachcomber’s paradise.

What changes have you noticed in the time you’ve been going there?

The beach constantly changes with wave and swell action. The dunes have recently been cordoned off so the erosion caused by visitors has decreased and allowed the dunes to stabilise. The major difference over the years is the increased numbers of 4WD vehicles on the beach.

Bruce Hartill, Fisheries Scientist, Group Manager – Fisheries and Marine Ecology (Auckland)
Beach: Woolleys Bay and Matapouri, north of Tutukaka

How long have you been holidaying there?

For the past 15 years.

What do you enjoy about it?

These are great all-round beaches, as they have good surf to play in with nice coarse sand. The fishing off the rocks can be pretty worthwhile, too.

What makes this location interesting scientifically?

Because I work on recreational fisheries, I always take an interest in the local fishing. When you look out from any vantage point you will usually see a small number of people fishing, and it might not seem like much is going on. When we do aerial surveys along this stretch of coast, you quickly realise that those individual fishers soon add up, so we need to know about their catch, as well as that taken by the fishing industry.

What changes have you noticed in the time you've been going there?

The fishing is fairly seasonal and the foreshore at Woolleys can vary substantially from visit-to-visit, depending on when the most recent storm was.

Dr Rob Bell, Principal Scientist – Coastal and Estuarine Physical Processes (Hamilton)
Beach: Ohiwa Beach and Harbour (between Opotiki and Whakatane in the eastern Bay of Plenty)

Dr Bob Bell. [Dave Allen, NIWA]

How long have you been holidaying there?

Initially with our family, we camped on the other side of the harbour at Ohope for 10 years, but switched sides to Ohiwa Beach seven years ago.

What do you enjoy about it?

It provides an uncrowded, sandy beach to swim or bodysurf, watch the moods of Whakaari (White Island) from our tent site – or kayak on Ohiwa Harbour, where godwits, terns, pied oystercatchers and dotterel nest.

What makes this location interesting scientifically?

Ohiwa settlement has had a chequered history, having originally set up on the sand spit as a thriving coastal port and hotel in the late 1800s. But it has experienced a few cycles of dramatic erosion, including houses falling into the sea in the mid-1970s, followed by incredible accretion episodes. For example, the present beach is some 200m seaward of where the eroded shoreline was, and a holiday home has been built on this accreted material. Observing king tides and storm damage to the coastal dunes is part of the holiday experience – not work –  for me, given our coastal group has its offices inland in Hamilton.

What changes have you noticed in the time you've been going there?

The beach has been rather stable for some time, with established pingao and spinifex plants. However, there are increasing signs of beach erosion since the king tides of early February 2015, and more so following ex-tropical Cyclone Victor in January last year. Maybe the next erosional phase is just around the corner. Over the same period there has been substantial change to the inner sandspit in the Harbour, with a new harbour channel cutting through the spit. This is good in some ways, as the roosting seabirds now have an “island” largely to themselves.

Nava Fedaeff, climate scientist, Auckland
Beach: Matarangi Beach, Coromandel

NIWA Climate Scientist, Nava Fedaeff. [Geoff Osbourne, NIWA]
How long have you/your family been holidaying there?

18 years

From a personal perspective, what do you enjoy about this particular beach?

The sand is fine and white, it almost looks like snow. Combine that with the emerald green water and the result is picture perfect. The beach is obviously great on a sunny day but I think it looks most beautiful when it is stormy.

What makes this location interesting scientifcally?

As Matarangi is a sandspit it’s fascinating thinking about how it formed over time due to longshore drift. The channel end of the beach/spit is very mobile and it is interesting to watch how it changes and shifts from visit to visit. Coming from a coastal and climate background, I particularly love visiting the beach after a big storm event to observe what kind of impact the weather has had. When walking down the beach it is very obvious the point at which there is a sudden disappearance of beach front houses. This is due to coastal set back zones which were imposed on new developments. Seeing policy like this in action is a good reminder of how far our understanding of coastal systems has come and that we now recognise how prone they are to change.

What changes have you noticed in the time you’ve been going there?

You only need to visit Google Earth and look at historical photographs of the sand spit to see how frequently the sand at the tip of the spit shifts around. It’s a great example of coastal process at play. In more recent years, there has been quite a bit of erosion at the end of the beach extending to the dunes. As a result, many pine trees around the edge of the golf course have been lost. Once again though this is a natural process and no doubt the beach will build out again in the near future.

In the summer of 2015 and 2016, Matarangi and large parts of the Coromandel coastline were inundated with red algae. I’d never seen such large and widespread amounts before, it made the nearshore waves red and stained the beach pink. In the last 10 years there has been considerable effort by the local community to implement pest control and replanting around the bush surrounding Matarangi as well as establishing walking tracks to access Rings Beach through the native bush. These actions have enhanced the bird life seen in the area.

Serena Wilkens, marine biologist, Wellington
Beach: Ruakaka Beach, Northland

Dr Serena Wilkens (credit: NIWA Dave Allen)

How long have you been holidaying there?

I grew up in Northland so spent many holidays playing on the beautiful white sand and in the surf.  Due to now living in Wellington I have not been there for a few years, but probably spent at least 20 years frequenting this beach when I did live there.

What do you like about this particular beach?

My early childhood love of the ocean (and later career as a marine biologist) probably originated here.  This beach was always a great place to visit.  The warm surf was great fun to play in and the white sand always yielded washed-up treasures which we collected as children, like shells and drift wood.  Occasionally we would see dolphins and Orca and the have to dodge the odd paddle crab in the shallows.

What makes this location interesting scientifically?

Ruakaka beach is a very popular surf beach located on the East Coast of Northland.  It’s at the gateway to the Whangarei Harbour and an integral part of the Ruakaka community.  Standing on the shore gives you a glimpse across the ocean at the Hen and Chicks Islands and Sail Islands and to the North, the majestic Mount Mania and Bream Head. 

What changes have you noticed in the time you've been going there?

The once sleepy seaside Ruakaka village has more recently become quite an exclusive coastal sub-division.  Many residents live their permanently, but many others now own very exclusive beach houses tucked behind the white sand dunes.  This area has now become one of the fastest growing areas in Northland.

Sadie Mills, marine biology technician, Wellington
Beach: Allans Beach, Otago Peninsula

Mount Charles, Allans Beach, and Cape Saunders. [Tomas Sobek CC BY 2.0, via Wikimedia Commons)]

How long have you been holidaying there?

Twenty years.

What do you enjoy about this particular beach?

It’s wild, beautiful, and some days you can be the only people on it. Yet it’s very accessible and is only 25 minutes from Dunedin.

What makes this location interesting scientifically?

The beach is home to Yellow-eyed penguins and sea lions as are many of the beaches around the Otago Peninsula. The beach also has the entrance to Hoopers inlet at one end of it, which has a whole lot of other estuary associated flora and fauna making it a pretty diverse area.

What changes have you noticed in the time you've been going there?

At the very end of the beach is a channel leading into Hoopers Inlet. Changes over time to the channel occasionally cause the entrance to become blocked up creating a whole lot of different conditions in the inlet as it becomes isolated from the sea. There are also changes to the sand dunes behind the beach, which can be very steep some years as they are eroded away.