The great New Zealand lupin debate and why it matters

First we need to talk about the lupin’s favoured environment being mainily the braided rivers which drain the Southern Alps – rivers that find it impossible to run in a straight line, and be anything other than dynamic.

When in flood braided rivers carry sediment from the ever rising mountains [geologically speaking] and landslides that frequent such a young country, and at every point where the water flow slows down the carried sediment settles onto the bed of the river, thus in time raising the level of same, and the river, seeking always the path of least resistance, flows off to the side. Thus during high water levels and floods the nature of this predominately gravel environment can change in several hours

The Hunter River that flows into Lake Hawea…
Hunter River


The delightful, endemic and endangered NZ banded dotterel / tuturiwhatu is one of many birds that has evolved to breed in these river beds. Despite exhibiting a variety of seasonal movement patterns ranging from sedentary behaviour, through migration within New Zealand, to trans-Tasman migration, it is hard to not love their comical stop-start actions…
Banded Dotterel


This is typical tuturiwhatu breeding ground – also shared with wrybill and other like minded birds. OK to us humans it is pretty desolate, but keep in mind it lets them see any predators, and when they do they mimic an injury to lure rats, cats and stoats away from off-spring…
Riverbeds 2


Well meaning flower lovers of decades ago decided to brighten up the desolation, and spread the non native lupin seed. They probably never realised the above, and that each seed being coated with a type of oil to preserve it, can survive for several years sprouting only when ideal conditions exist. The perfect seed for such a dynamic bed – they of course then become impossible to get rid of, apart from annual spraying and that is not a cunning or cheap thing to do in waterways annually…
Lupins in The Ahuriri river valley


And then there are wilding pines – these ones have been sprayed. The terrain hosting cushion type vegetation is again the sort chosen for nesting…
Tasman Riverbed


No one denies the lupins look beautiful. And by-the-way after the brief flowering is over they become anything but ethereal, and more of an eyesore…
Lupins in The Ahuriri river valley


Another beautiful frequenter of the braided river environment is the black fronted tern tarapirohe. They spend hours swooping for bugs above and on the glacial silt laden blue/grey water surface, and of course breed nearby…
Tern


The natural state as another dawn breaks on a braided river in The Southern Alps…
Tasman Riverbed dawn light


If only lupins could be confined to roadsides! But even in such a place they invite suicide by flowery eyed tourists, toting cameras that are scant protection against the 110km/hr traffic that rushes by their nearby vehicles, the parking of which is more spontaneous than well thought out…
Lupins again


The two villains together on the shores of Lake Pukaki…
Lupins and a wilding pine - Lake Pukaki


The uniquely billed wrybill / ngutuparore which breeds only in braided rivers of the South Island. It is the only bird in the world with a laterally-curved bill [curved to the right], which it uses to reach insect larvae under rounded riverbed stones. Wrybills are completely dependent on the greywacke shingle of the riverbeds…
Wry bill


Makarora Braided River – an under estimated biodiversity hotspot

Makarora braided river approaching the head of Lake Wanaka. BRaid (2017).

From the headwaters of the Makarora on the eastern flanks of the Southern Alps near the Haast Pass in Mt Aspiring National Park. The Makarora River flows south west and is joined by the Blue and the Young Rivers, then extending its braid plain further meeting its confluence with the Wilkin River before dissipating its energy into the head of Lake Wanaka.

Driving along the Wanaka Haast highway the Makarora braided river habitat is often overlooked or missed totally, yet the Makarora River is quite spectacular and is an important habitat for a number of important endemic New Zealand bird species and an array of other flora and fauna. A section of this captivating landscape can be seen in the video footage https://www.youtube.com/watch?v=g242GDSweiA produced by Braided River Aid (BRaid) on a frosty July morning. Braided rivers (defined by migrating, weaving channels of water between temporary islands of gravel) are iconic habitats unique to New Zealand encompassing an array of wildlife found nowhere else in the world.

There are a number of endemic bird species which depend on this habitat to complete their breeding cycle. During spring, braided river birds such as wrybill, black-fronted tern and black-billed gull can be seen returning to their breeding sites within the South Island.

The wrybill or ngutuparore is the only bird in the world that has a specialised bill which bends to the right, allowing it to feed beneath boulders and along the surface of the water on biofilm. This charismatic grey plover is nationally vulnerable relying on the unique braided river habitat to maintain its life cycle.


Adult wrybill nesting within braided riverbed (OSNZ courtesy of Dianne Parker).

Here the wrybill nests, lays eggs and rears chicks, its cryptic colouration blended effortlessly amongst the alluvial gravels of the riverbed. From January, onward wrybill flocks migrate north to their wintering grounds mainly in the Manakau and the Firth of Thames with smaller flocks elsewhere.

Juvenile wrybill at Miranda chenir shell bank (Firth of Thames) wintering site. Rachel Hufton

The black-fronted tern or tarapirohe, nationally endangered, is an attractive and highly distinctive bird in breeding plumage, slate grey contrasting with a black cap and bright orange bill and legs. Black-fronted terns also breed only on braided riverbeds of the eastern and southern South Island, from Marlborough to the Southland within small colonies and have now returned to Makarora. Their eggs and chicks are also well camouflaged against braided river gravels.


Black-fronted tern roost on a gravel island at Makarora. Rachel Hufton.

The black-billed gull or tarapuka is the most threatened gull species in the world. Though still relatively abundant, numbers of birds throughout the South Island have rapidly declined. The black-billed gull is more slender than the red-billed gull, with a longer bill and nests in colonies mainly on sparsely vegetated gravel riverbeds.


Black-billed gull colony on the Makarora braided river. Rachel Hufton.

Other braided river birds present on the Makarora include banded dotterel and South Island pied oystercatcher. The banded dotterel is the most common small plover of New Zealand coasts, estuaries and riverbeds but is nationally vulnerable. Banded dotterel breed within the braided river habitat but also use other habitats for nesting. Often seen running along the waters edge whilst foraging for invertebrates.

The South Island pied oystercatcher is the most abundant oystercatcher in New Zealand but is declining nationally. Pairs of South Island oystercatchers are often seen breeding in braided river beds but also within adjacent farmland. The conspicuous black and white plumage, distinct call and long red bill make this a familiar species.

Braided rivers are dynamic habitats, and as a result are threatened by a wide range of factors. These include habitat loss due to hydroelectricity development, weed encroachment of braided river breeding habitat, and recreational use of rivers. But the most significant impact is predation by introduced mammals.Black-fronted tern’s, wrybill’s and their nests are preyed on by rats, stoats, ferrets, ferral cats and hedgehogs. In addition, predation by southern black-backed gulls and Australasian swamp harriers, both of which have become more numerous following changes in landuse.

Considerable conservation management efforts have been made on some New Zealand braided river habitats, predominantly in the McKenzie Basin region and Canterbury which have positively contributed to braided river bird populations. This is evident in the Tasman Delta where Kaki black stilt have been reintroduced. A now rare species, once historically found throughout the South Island braided rivers.

The Makarora braided river requires collaborative effort to help restore, maintain and promote these specialised braided river birds to flourish for future generations worldwide. This can in part be achieved through advocacy and awareness raising. A recent braided river biodiversity and conservation workshop delivered at Makarora by a local ecologist, was a great way for students to connect with nature whilst learning about braided rivers.

Students and staff from Makarora located school camp following interactive workshop on braided river biodiversity, conservation and river safety (Andrew Shepherd).

Makarora braided river birds need help to successfully fledge their chicks this year without being subject to invasive mammalian predation from stoats, rats and hedgehogs. Any donations towards invasive mammalian trapping efforts on the Makarora braided river will be gratefully received by the threatened bird species that are beginning to nest. Donations or the sponsoring of traps can be made through the Southern Light website. With thanks.

Wrybill chick (OSNZ courtesy of Craig Mckenzie).

 

References

BRaid (2017) Drone video footage. Makarora and Wilkin River.

Hauer, RF. & Locke, H et al (2016). Gravel bed river floodplains are the ecological nexus of glaciated mountain landscapes. Applied Ecology. Vol 2, No 6.

nzbirdsonline.org.nz

Peat, N. Patrick, B Rebergen, A. (2016). Rivers Rare. The first 25 Years of Project River Recovery (1991 – 2016). Department of Conservation, Wellington, New Zealand.

Wittington, RJ. (2015). The foraging ecology of non-breeding wrybills (Anarhynchus frontalis) in the Firth of Thames: a thesis presented in part fulfilment of the requirements for the degree of Master of Science in Ecology at Massey University, Palmerston North, New Zealand.

 

Further information contact Ecologist: Rachel

 

Today’s News: New Zealand native birds in a desperate situation, says Environment Commissioner

The takahē was once thought to be extinct, but in 1948 it was rediscovered by Dr. Geoffrey Orbell, [who incidentally I remember meeting as a child, when he was the next-door-neighbour of my grandparents]. He found it high in the tussock grasslands of the remote Murchison Mountains, Fiordland. Currently there are just over 300 left in the world - approx. half in the wild. photo Southern Light

takahe
The takahē was once thought to be extinct, but in 1948 it was rediscovered by Dr. Geoffrey Orbell, [who incidentally I remember meeting as a child, when he was the next-door-neighbour of my grandparents]. He found it high in the tussock grasslands of the remote Murchison Mountains, Fiordland. Currently there are just over 300 left in the world – approx. half in the wild. photo Southern Light
Today a very timely report was released by Parliamentary Commissioner for the environmentDr Jan Wright. It follows on from a very succinct series of non political reports including the use of 1080 poison to help our birds:

In a new report, the Parliamentary Commissioner for the Environment says New Zealand’s native birds are in a desperate situation.

“Despite the efforts of many, most of our native birds are in trouble.” said the Commissioner, Dr Jan Wright.
“A third are in danger of becoming extinct. This includes the kea – the only alpine parrot in the world. Another is the wrybill – the only bird in the world with a beak that curves to the side. And another is the whio – a duck that paddles through rough water like a white water kayaker.”

Wrybill
Wrybill in the Makarora braided riverbed, Mt Aspiring National Park. photo Southern Light

The Commissioner’s report is based on a vision of restoring abundant, diverse, and resilient birdlife on the New Zealand mainland.
Dr Wright says the Government’s aim of eradicating possums, rats, and stoats by 2050 is good because it focuses attention on the most pressing cause of the decline of native birds – predators. But she says a plan of action is urgently needed.

“We need sustained control of predators over more large areas, so that bigger populations of birds can thrive. Small isolated bird populations can become inbred. We must not let our birds drift to the shallow end of the gene pool”, said Dr Wright.
The Commissioner also stresses the need for action on feral cats.

“These bird killers now almost certainly number in the millions in the countryside and along forest margins.”
The last chapter of the report contains seven recommendations to the Government. They include high priority research on controlling predators, increased protection of important bird habitats, and investigating new sources of funding.

“Ninety-three of our bird species are found in no other country”, said Dr Wright. “We must look after them. Our birds need help not only in national parks, but on farms, along rivers and coasts, and in cities. This is a battle for all New Zealanders.”

Source: Native birds in desperate situation, says Environment Commissioner

The whole document “The report, Taonga of an island nation” is available here as a pdf >>