Thursday, April 28, 2011

Bitterns – “kings of the wetland’

Bitterns – “kings of the wetland’
Peter Langlands
29 April 2011

Duck shooters are advised to take care not to accidentally shot a bittern during the upcoming season. These large birds are an endangered species and listed by DOC has “Nationally Threatened” and are fully protected.
Bitterns have evolved a streaked brown and black plumage to camouflage in with reed beds. The birds are about a kilogram in weight, half way in size between a mallard and Canada goose, but have a large pointed bill. Bittern often startle you as these large birds will flush out of the reeds at short range.
Bittern (or as they are known Matuku) have benefited from waterfowl wetland enhancement work done by Fish and Game and private individuals. But with over 90% of our wetlands drained the bittern have over all declined. Bittern are very much a bird of our larger wilderness wetlands, but are often sighted in drains and on farmland from March to June.
Although common at the Whangamarino wetland are bittern are quite scare and spread out though much of the country with a nationwide population of around 750 birds. If any shooters sight bittern or have photographs of bittern I would be keen to hear from you as I am collecting bittern records for a national database to assist with the conservation of the species (email – langlands@xtra.co.nz).

Photograph shows a bittern in flight at Te Waihora (c. Peter Langlands- Bittern researcher).

Tuesday, April 26, 2011

Pingao


This golden sedge is an endemic species. Kaitorete Spit which separates Te Waihora from the sea has the most significant pingao ecosystem on the mainland of NZ. A special place.



http://www.doc.govt.nz/publications/conservation/native-plants/pikao-or-pingao-the-golden-sand-sedge/

Friday, April 22, 2011

Shovelers now moulting into breeding plumage


Thousands of shovelers seasonally occur at Te waihora. These dfucks have a spoon shaped bill and feed by filter feeding on plankton. The lake offers a bountiful food supply.

Monday, April 18, 2011

A stronghold for royal spoonbills


Flocks of up to 150 Royal spoonbills - around 10% of the NZ population of this graceful bird have recently been sighted at Lake Ellesmere. Juvenile flounders are an important food source for these birds.

Thursday, April 14, 2011

Canada geese at dawn- lower Selwyn Huts


Love the golden-misty dawns over Te Waihora's expanse

Waihora is Canterbury's stronghold for bittern (Matuku)

Conserving New Zealand’s bitterns- an eleventh hour conservation attempt
Peter Langlands
05 September 2010

Bitterns are an icon of our wetlands. Few birds show such a high level of adaptation to wetlands than bitterns. In fact their plumage has evolved to allow then to merge in with reed beds, a habitat that bitterns are dependent upon for their survival. Sadly it is the bittern’s specialised habitat requirements that are now putting this species at risk in many regions in New Zealand. Only Northland and Waikato have significant bittern populations remaining. Throughout the remainder of New Zealand bitterns occur only in small and fragmented populations. In some regions such as Marlborough the birds are on the edge of regional extinction. In Canterbury, where I live the population is estimated at between 30-50 birds. The NZ population may be as low as 500 birds- perhaps a maximum of 2000. Still making the bittern rarer than the kokako!
With fragmentation many other factors now come into play with bittern conservation. For example with birds living in wetlands with more edge zones the chance of predation increases, sadly there is little data to confirm this, but the increase on the harrier population is likely to impact on bitterns as are mammalian predators such as stoats and Norwegian rats. Also bitterns are highly vulnerable to collision events such as getting hit but cars and flying into power lines. For bittern the bird’s decline may be one of death by a thousand cuts. Bitterns requite large, productive wetlands- a habitat still in decline. Sadly only about 5% of our original wetlands exist, and the few surviving wetlands are under increasing threat.
For me the experience of going to a wetland and knowing that no bitterns are left would make me feel empty. Bitterns really are that one bird that symbolises a sense of wilderness with wetlands. The reality is that bitterns are the test of our commitment to conserve biodiversity. As a species they have been left to the eleventh hour to consider in active conservation plans. Yet there is hope. We have detailed information on the habitat requirements of bitterns and with some financial backing and commitment to create suitable habitat near where the surviving populations remain this species can be saved. Its future truly does rest in our hands!

Wednesday, April 13, 2011

Key zones for wrybills at Lake Ellesmere


Key zones for wrybills at Lake Ellesmere

The attached Google map shows two zones (in white) that are critically important feeding sites for our threatened wrybill- both these sites need to be protected form environmental damage. Embankment Road offers a good access point from which to view wrybills- BUT PLEASE DO NOT DRIVE ONTO SALTMARSH

Marsh Crake- a cyptic inhabitant of the lake's reed beds


Marsh crakes are found in areas of raupo and Carex around the lake. These birds are tiny- about the size of a starling. They are related to wekas. Despite their tiny size marsh crakes have huge feet. Often they can be heard crashing through the raupo and you expect to see something bigger ! Marsh crakes are most active at dusk and through the night. By sitting quietly on the edge of a raupo bed you may spot this tiny but strikingly coloured bird .

Waihora- Wharekai of tuna



"Food basket of eels"

Waihora is an amazing rich lake providing a bounty of seasonal foods. Eels can be harvested recreationally from the lake's inflowing waterways and are ideal for smoking- a rich food source- locally available to be treasured. The recreational limit is six per day but I often just take one or two for the smoker as they are very rich. When smoked , thinly slice and put on toast with avocado and cracked pepper- devine. It is best to take eels in the 1-2 kg range- an ideal size for preparing. Larger eels should not be taken and left to hopefully complete their spawning run into the deepwater trence off New Caledonia ? The lake was open to the sea a couple of weeks ago- allowing eels to escape the lake on their Autumnal spawning migration.

Tuesday, April 12, 2011

LII - Riparian plantings


Landowners on the LII have done a lot of good work to fence off, plant and manage the riparian margins of this river ( The LII) which is the main freshwater river flowing into Waihora- an outstanding waterway for wildlife.

Sunday, April 10, 2011

Te Waihora- an outstanding trout fishery


Historically the lake's trout fishery was the best in NZ- now there are still some trophy fish to be caught such as this 10 pounder caught on the opening day 1 October 1992 under the Kaituna River Bridge by Peter Langlands - Photo by Don Scott- Christchurch Press

A multi-million dollar eel fishery of national importance


The lake supports an eel fishery of national significance. A high proportion of the eel catch goes into the export market. A recent haul of eels from Taumutu- a strategic location for eeling- situated close to the lake's outlet.

NZ's fifth largest lake


This view illustrates the expanse of Te Waihora. Photograph taken in 2011

Need for monitoring of bird life

A present there is very little systematic monitoring of Te Waihoras bird life ? Surely to manage the lake we need annual counts or a series of monthly counts (to compare with data from the mid- 1980's) to measure the value of the lake to wetland birds

Te Waihora- the south Islands most productive freshwater wetland environment


Without a doubt Te Waihora is our ( the South Island's) most productive freshwater environment. This photograph showing the LII River mouth and adjoining wetlands gives an indication of the complexity and richness of the lake's wetlands. Now as we move into 2011 we need to address the health of the lake which sadly, overall, has been neglected for the last 40 years. Small scale initiatives at Harts Creek and on small wetland areas around the lake by organisations such as WET, ECAN and Living streams Groups have enhanced some areas- but the lake needs more awareness and management to make the most of this resource- both for wildlife and economic values ( the lake has a nationally important eel fuishery and regionally important flounder fishery).

Te Waihora- Lake Ellesmere facts-

Lake Ellesmere/Te Waihora is New Zealand’s fifth largest lake. The 20,000 hectare brackish lake is shallow. Average depth is 1.4 metres with a maximum depth of 2.7 metres near Kaituna.

DOC looks after approximately 35 percent of the margin of Te Waihora, plus other lands in the wider catchment area, the largest of which is McQueen’s Lagoon on the Halswell River/Huritini.



Wildlife
Te Waihora is of outstanding national and international importance for wildlife. 166 species of birds have been recorded here, including 133 indigenous species - with up to 98,000 birds on the lake at one time.

There are number of wildlife reserves around the lake: Harts Creek, Selwyn, some of which are also refuges, offering greater protection.

The lake supports a diverse range of introduced and native fish including whitebait/īnanga and tūna/eel.

Cultural significance

Aerial view of Lake Ellesmere and
Kaitorete Spit
Te Waihora is an area of cultural, natural, historic, recreational and commercial importance to many people. To Ngāi Tahu, Te Waihora represents a major gathering place for food and natural materials and an important source of mana.

Kaitorete Spit

Kaitorete Spit is an impressive landform, about 28 km long. It was formed about 6000 years ago by gravels transported by the Rakaia River and pushed into place by the Pacific Ocean.

It’s the largest remaining area in New Zealand of native sand binder/pingao, a bright-orange plant prized for weaving. Kaitorete is also home to other threatened plants and animals, some of which are unique to this location, such as woolly head Crapspedia ‘Kaitorete’, and a flightless moth! It’s a fantastic place to spot katipo spiders and lizards too.

Source - DOC www - 2011

Saturday, April 9, 2011

Matuku haven


Te Waihora is without a doubt the most important wetland complex in the Canterbury Region for Matuku- bittern. These large heron like birds are spectacular to see as they suddenly fly up out of reed beds. The Harts Creek wildlife Reserve and adjoining wetlands is a stronghold within Te Waihora for bitterns. This bird was photographed feeding amongst watercress, adjoining a small spring creek flowing into the lake, in early April 2011

Te Waihora- a nationally significant wetland for crested grebes


Almost 10% of NZ's crested grebe population inhabits Te Waihora and its' tributaries ( Kaituna River and Hart's Creek). Crested grebes breed at the lake at the Hart's Creek Wildlife Reserve and also on the Kaituna River- one of the few locations where crested grebes breed on a river environment. The total NZ population of this majestic bird is estimated at 600.

Thursday, April 7, 2011

Cattle herd within sensitive wetland vegetation


Are cattle grazing within our wetland environments appropriate? cattle grazing in reed beds just north Of Harts Creek Wildlife Reserve - Lake Ellesmere .

Kotuku at Ellesmere


About 10 birds (10%) of the NZ population are on the lake at present- so elegant.

Kahi at Lake Ellesmere


Kahi
Magical having a kahi only half an hour from my home in Christchurch- such a distinctive call. This critically endangered bird is very much for me an icon of the wild spaces on the rivers and coastal lagoons of Canterbury.