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There are far mightier braided rivers in Canterbury, but the modestly sized Ashley-Rakahuri is a taonga of a value disproportionate to its size.

Keen tramper, ornithologist, and photographer Steve Atwood takes us to this ecological gem, just a stone’s throw from Christchurch city…

The world's most endangered gull — the black-billed gull — nesting on the Ashley-Rakahuri. Photo copyright Steve Attwood.

The world’s most endangered gull — the black-billed gull — nesting on the Ashley-Rakahuri

For the most part the Ashley-Rakahuri weaves through highly modified rural farmland where indigenous natural New Zealand has almost been scrubbed from existence. But the braided river channels of the river itself are a largely unmodified natural environment that has been a unique feature of the Canterbury plains for eons.

A braided gem. Photo courtesy of Ashley-Rakahuri Rivercare Group

A braided gem. Photo courtesy of Ashley-Rakahuri Rivercare Group

Braided rivers are rare in the rest of the world, with New Zealand considered a hot spot, and Canterbury the centre of that, with 59% of the country’s braided river surface area. They are the home of highly adapted braided river specialists, chief among them being the birds.

Ngutuparore / wrybill — the iconic braided river bird

Ngutuparore / wrybill — the iconic braided river bird

Among its labyrinthine waterways, dynamic shingle islands and stony banks breed some of the most endangered birds in the world.

In a relatively short span of riverbed quite close to the township of Rangiora nest three of the principle and most threatened braided river specialists: The black-billed gull (the most endangered gull in the world), the unique wrybill (under threat and the only bird in the world with a bill that bends sideways), and the beautiful black-fronted tern (also an endangered species).

Tarapiroe / black-fronted tern — in flight above the Ashley-Rakahuri waters. Photo copyright Steve Attwood.

Tarapiroe / black-fronted tern — in flight above the Ashley-Rakahuri waters

Where the Ashley-Rakahuri reaches the sea, just 25 kilometres north of Christchurch, it spreads out into a large, generally unmodified estuary that is ranked as an internationally important wetland with a host of resident and seasonally visiting birds.

It is a vital stopover site for birds migrating up and down the coast, and beyond; including the iconic kuaka (bar-tailed godwit) and other Arctic migrants that live out their winter in our summer.

Karoro - black-backed gull chick with a penthouse view - Ashley-Rakahuri Estuary. Photo copyright Steve Attwood.

Karoro / black-backed gull chick. Ashley-Rakahuri Estuary

Unfortunately, the ecological values of these braided river systems are increasingly threatened; most have been invaded by introduced weeds and introduced mammalian predators, and are further degraded by a wide variety of human activities.

Male banded dotterel with its chick  among the river stones. Photo copyright Steve Attwood.

Male banded dotterel with its chick among the river stones

From its gorge—a popular swimming picnicking and fishing spot—to its mouth, the Ashley-Rakahuri, being so accessible and so close to Christchurch, is particularly vulnerable to these pressures.

The numbers of birds along the river have declined and its ecological rating downgraded accordingly, from ‘outstanding’ to ‘nationally important.’

Safe among the stones? Like the other river breeding specialists, the banded dotterel is a threatened species under risk from human-caused environmental degradation

Safe among the stones? Like the other river breeding specialists, the banded dotterel is a threatened species under risk from human-caused environmental degradation

But, being so small in comparison to the bigger braided rivers, the Ashley-Rakahuri also offers a unique opportunity for effective intervention; initiatives to protect the river in places where the most threatened of birds are known to feed and breed—predator trapping, weed clearance, public education, vehicle discouragement and monitoring—are showing signs of at least stopping the decline of the endangered species, perhaps even reversing it.

Tarapiroe chicks hidden among the stones. Photo copyright Steve Attwood.

Trapping of introduced mammalian predators helps protect these vulnerable tarapiroe chicks hidden among the stones

While the protection efforts at the Ashley-Rakahuri focus on the wrybill, black-billed gull and black-fronted tern, many other bird species benefit.

The braided river is home to such other key native species as the tuturiwhatu (banded dotterel – Charadrius bicinctus), the poaka (pied stilt – Himantopus himantopus) and the torea (pied oystercatcher – Haematopus ostralegus).

Juvenile kaki / black stilt benefit from the protection efforts on the Ashley-Rakahuri. Photo copyright Steve Attwood.

Juvenile kaki / black stilt

The very rare kaki (black stilt – Himantopus novaezelandiae) has bred occasionally on the river in recent years (mated with a pied stilt) and over-wintering kaki are regularly seen in small numbers on the estuary.

White-fronted terns. Photo copyright Steve Attwood.

White-fronted terns share space on the Ashley-Rakahuri with their rarer black-fronted cousins

Migratory wading birds are the spring through to autumn stars of the estuarine environment. Here I have seen godwit, knots, whimbrel and turnstone.

The number of resident species at the estuary is also substantial. Along with the mudflats, dunes, sand and shingle banks are freshwater ponds and creeks, reed and raupo beds, scrublands and grassy flats, providing a multitude of environments for birds to live, breed and feed in.

Tōrea pango / variable oystercatcher caught in a sandstorm. Photo copyright Steve Attwood.

Tōrea pango / variable oystercatcher. Caught in an estuarine sandstorm

The native birds I have seen along the Ashley-Rakahuri include: the shags (pied, little, spotted and black); the large waders (Australasian bittern, royal spoonbill, white heron and white-faced heron); the intermediate-sized waders (spur-winged plover, South Island pied oystercatcher and variable oystercatcher and oystercatcher hybrids); the waterfowl (black swan, grey teal, New Zealand shoveler, paradise shelduck, New Zealand scaup and Australian coot); the terns (black-fronted, white-fronted and Caspian); the gulls (red-billed, black-billed and southern black-backed); and the birds of the forest, air and riverbank (harrier, welcome swallow, kingfisher, grey warbler, silvereye, and fantail).

Royal spoonbill. Photo copyright Steve Attwood.

Another large white wader that inhabits the estuary — the amazing royal spoonbill

A kurwuwhengi (NZ shoveler drake) with a kuaka (godwit) in the background. Photo copyright Steve Attwood.

A kurwuwhengi / NZ shoveler drake with a kuaka / godwit in the background

Parekareka / spotted shag. Photo copyright Steve Attwood.

Parekareka / spotted shag can be seen at the Askley-Rakahuri estuary all-year round

The estuary is also home to large number of introduced game birds such as mallard and Canada geese; and introduced field birds such as skylark, chaffinch, yellowhammer, redpoll, sparrow and goldfinch.

The above lists are by no means exhaustive as they are only my observations; other species are recorded as regular, occasional or rare visitors.

This abridged post is from Steve Attwood’s blog. Read the full story (with more gorgeous photos) there.

Thanks Steve for letting us share it here on the Conservation Blog.

By DOC’s Government Support Manager (and keen photographer), Brian Sheppard

New Zealand’s magnificent shorebirds are masters of their elements but they only reach this supreme state of being after rigorous training of mind and body.

Variable oystercatcher. Photo © Brian Sheppard.

Variable oystercatcher

To a casual observer, the birds are just mooching around, or foraging for food, but look closer. You might be surprised to see what they are really up to.

I dropped in on a couple of Wellington’s shorebird chapters: the beach chapter at Petone, and the city branch at Wellington Harbour, to watch their training sessions.

Two oystercatchers wading in the shallow water. Photo © Brian Sheppard.

Finishing afternoon tea

A pair of oystercatchers were just finishing their afternoon tea at the beach to fortify themselves for their self-improvement class. The first one led the way, closely followed by an inquisitive red-billed gull.

Oystercatcher closely followed by an inquisitive red-billed gull. Photo © Brian Sheppard.

Oystercatcher closely followed by an inquisitive red-billed gull

The tide was in and pounding against the end of a concrete pier.

No fear!

No fear!

The pair of oystercatchers took their positions at the end of the pier where the raging sea would drench them. They showed no fear but just stared down the approaching waves.

The gulls arrived shortly afterwards but they were the new entrants to the class, taking a back row – watching and learning from the masters.

Gulls take a back row – watching and learning from the masters

Gulls take a back row – watching and learning from the masters

With the skills learned from the beach, the gulls tried to apply them, in the comparative privacy of Wellington Harbour. Their test was to hone their flight skills on a spectacularly windy winter’s day. Their test area was the outfall from the wetland next to Te Papa.

Te Papa testing ground. Photo © Brian Sheppard.

Te Papa testing ground

As they arrived, their first task was to stand their ground in the face of the wind that was blowing the falling water back the way it came.

Red-billed gull. Photo © Brian Sheppard.

Beaten up by the wind

Following the example shown by the oystercatchers, the lead gull stepped to the edge to show no fear while being pelted by the spray and then to execute a flawless take-off.

Clearly a bit more practice was needed. He was nearly wiped out by a cross wind. It must have dented his confidence as I saw him later retaking his beginner’s take-off class. By that time, I had to get back to work, so I never witnessed the landing.

Red-billed gull. Photo © Brian Sheppard.

Red-billed gull

New Zealand is famous for its land birds like the kiwi and kākāpō. But just as remarkable and unique are our sea and shore birds.

More than a third of the 80 or so species of sea and shore birds that breed in New Zealand are found nowhere else on Earth, including the variable oystercatcher.

Both variable the oystercatcher and red-billed gull are native to New Zealand and are often found around our coast.

Do you have a ‘chapter’ of these shorebirds near you?

Looking for a slightly different day walk in the Wellington region? Then the Makara Walkway could be it. It’s one of my favourite short walks in the area.

Makara Beach.

Makara Beach

The Makara Walkway starts at Makara—a 16 km drive from Karori, over Makara Hill (watch out for cyclists).

Ohariu Bay is the starting place for the walk.

The best option is to walk around the beach, past Wharehou Bay, into Ohau Bay.

Both of these bays are popular with local fisherman and divers.

This is a fantastic piece of wild coastline, with a number of impressive rock formations and large number of seabirds—especially the loud and bright beaked oystercatchers.


Variable oystercatcher

Another plus with this walk is that it is sheltered from the cold southerly wind. So, even if there’s a strong southerly, the walk is still pleasant.

Having said that, it does get hammered in a Nor’wester, so check the wind direction and speed before you head off—there is very little shelter along the track.

Rock formations along the Makara Walkway.

Rock formations

Once you get to Opau Bay the track heads up the hill (a little steeply) to Fort Opau, which was garrisoned by 100 soldiers during World War II. There is also an historic Māori pa site.

The views from the top are breathtaking: 360° views, including Mana Island, Kapiti Island, the Tararua Range, Mount Taranaki, the Marlborough Sounds and the giant wind turbines from Project West Wind, which has its own network of tracks.

This point is also a perfect place to watch the sun go down, or come up, if you’re super keen!

Views of the coastline along the Makara Walkway.

Great views along the track

From here it’s a downhill walk back to Wharehou Bay, and a short walk back to Ohariu Bay and your vehicle.

Wind turbines on the hills of Makara.

Wind turbines in Makara

The secret reason I love this loop track is that I proposed to my wife at the top—in a spot where we could see all the places that we had been tramping together.