Please help us find our missing bittern!

Please help us find our missing bittern! By Emma Willams PhD researcher on bittern 4 June 2015 Last Spring we put transmitters on six male Australasian bitterns at Lake Whatumā, near Waipukurau, Hawkes Bay. When the breeding season finished in January, and the water levels on the lake dropped, all six bitterns left the area. We have been able to re-find five of these birds but the sixth bittern, Tama Tomoana, is still missing! Can you help us find him? We’re asking anyone with access to telemetry gear to check any wetlands, streams, farm ponds, drains and small lakes in their area. We believe he is still in the Hawkes Bay area but in reality he could be anywhere in the country. Recently an Australasian bittern carrying a satellite transmitter in Australia travelled 550 Km, across two state borders, within 11 days!…We don’t know if our bitterns travel the same distances. We’re assuming that Tama could be anywhere! Join the national hunt…and if you find him please contact Emma on 0272462274,bittern.wills@yahoo.com.

Protocols for the inventory and monitoring of populations of the endangered Australasian bittern

Colin DOC Technical Series Latest publication March 2015 38. (Botaurus poiciloptilus) in New Zealand. C. O’Donnell and E. Williams 2015. DOC Technical Series 38. 40 p. (PDF, 4,143K (opens in new window)) Summary: There is an urgent need for conservation managers to undertake inventory and monitoring programmes for the endangered Australasian bittern (Botaurus poiciloptilus; matuku) in New Zealand. Such programmes can be used to determine the distribution and relative abundance of Australasian bitterns nationally; identify significant habitats, sites and populations to enable their protection and implement conservation management; measure the response and effectiveness of management practices; and measure the health of wetlands. This report describes four protocols for the inventory and monitoring of Australasian bitterns, and also provides a guide to choosing the most appropriate method for a particular objective. The protocols build on previous methods that have been developed in other countries, testing and adapting them for New Zealand conditions, and extending them through the use of automatic recording approaches, which allow efficient sampling in remote and inaccessible locations. The protocols represent current ‘best practice’, but further refinements will likely be made in the future.

Update from the New Zealand bittern research team: This season, as well as monitoring bitterns at key wetlands nationally, the bittern team has been busy calibrating our monitoring methods. Our aim has been to see how the number of bitterns detected with each method compares with the actual number of bitterns present at the site. To do this we’ve needed to capture as many bitterns as possible at one site (Lake Whatumā). Each captured bittern has been marked through the attachment of a radio transmitter. The attachment of these transmitters enables us to re-find and identify marked birds even when they’re hidden in the dense Raupo. Bitterns are difficult to catch due to their cautious nature and the inaccessibility of their natural habitat. A few bitterns have been caught before in New Zealand, but only by firing a net gun onto the bird from a helicopter - something that is very risky for the bird as well as expensive. To avoid having to use these intrusive methods we’ve been trialling some capture methods that have been used on closely related bittern species overseas. This is the first time in New Zealand that Australasian bitterns have been studied intensively like this. As very little is known about bitterns we are hoping that data from this study can also answer questions like: Where do bitterns go after the breeding season? What habitat types are important to bitterns for feeding and breeding? How big are home range sizes? And do bitterns come back to the same sites every year to breed? These are important questions that no one has the answers for yet. Once answered, this knowledge will be used to identify and manage sites that are important for bitterns, helping us to help prevent the extinction of this fascinating Endangered bird. This season our work was partly funded through the Arawai Kakariki Project and a Ducks Unlimited NZ grant.

The Maori Lakes - a high country stronghold for bittern

Automatic sound recorders have picked up at least three booming bitterns at the Maori Lakes in the O Tu Wharekai Conservation Area this spring. For bitterns in Canterbury the raupo beds are a critically important habitat for the last remaining 50-7

5 birds in the region

Bitterns return to the mouth of the Avon River

For the third year in a row ( 2012-2014) bitterns have returned to the mouth of the Avon River. It is very pleasing to have such a rare bird within Christchurch City. In 2012 I assisted the Christchurch City Council/Andrew Crossland and other park rangers with a systematic survey of the lower Avon River and adjacent reed and raupo beds in the adjoining Avon-Heathcote River with the pleasing result of five birds being found. This result makes the mouth of the Avon River one of the five most important wintering sites for bitterns within Canterbury.

Bittern fact sheet by Emma Williams

Australasian Bittern Botaurus poiciloptilus (Wagler, 1827) Order: Ciconiiformes Nationally Endangered/Endangered Family: Ardeidae Other names: Matuku, Boomer, Bunyip, Black-backed or Brown bittern, Bull-bird (English), Avetoro Australiano (Spanish), Butor d’Australie (French), Australische rohrdommel (German) Geographical variation: One species. Plumage does vary but this is not thought to be geographical. Bitterns are extremely cryptic and rarely seen. This is due to a combination of factors, including their secretive/evasive behaviours, crepuscular habits, inconspicuous plumage and the inaccessibility of their habitat. As a result, their presence is most commonly discerned through hearing the distinctive ‘booming’ call of the males during the breeding season. Despite this, many an enthusiast has been treated to a sighting in areas where birds are more conspicuous, such as wetland/farmland edges, dykes, drains and even roads. Such sightings never disappoint, as bitterns can be behaviourally fascinating; with interesting copulation rituals, booming postures and their infamous ‘freeze’ stance. Identification [74 cm, weight: males 1400g and females 900g] Bitterns are large, stocky birds, with streaky dark-brown and beige plumage on their thighs, chest, breast, and throat; with dark brown along the back and neck. The head is dark except for pale beige around the cheek, forming either a pale superciliary- or eye-stripe. Plumage varies greatly but does not appear to be related to region, season or sex. Some authors have suggested age may explain some variation (Heather & Robertson,1996); with juveniles possessing a more ‘buffy’ plumage, which darkens as they mature, and then may pale again as the bird ages (Teal, 1989). However, this still hasn’t been confirmed and there have been so few opportunities to age birds that it is currently not relied upon in the field. Voice: Bitterns produce a sequence of distinct ‘Wooom’ calls known as ‘booms’. These calls are thought to be produced by males only. Each call sequence consists of several individual booms, ranging from 1-10 booms per sequence (bps), with a mean of 3 bps . These sequences are often repeated at regular intervals that appear consistent to individual birds. The function of these calls is assumed to be related to breeding as their production is almost entirely limited to the breeding season. Booms are commonly preceded or interceded with gasps or inhalations. Females are largely silent but are said to produce a bubbling noise when they return to the nest (Marchant, 1990; Soper, 1958; Teal, 1989) and a nasal ‘kau’ call when alarmed (Teal, 1989). Birds in flight have been reported to produce profound, resonant ‘kau kau’ calls or a more nasal single ‘kau’ call (Teal, 1989) Distribution and habitat Found throughout New Zealand, as well as parts of Australia and New Caledonia (BirdLife International, 2011). Studies in Whangamarino wetland, New Zealand suggest bittern mostly inhabit mineralised and semi-mineralised wetlands (Ogle and Cheyne, 1981), although they are often spotted foraging in drains and wetland/farmland edges. Population The New Zealand population is thought to have <900 individuals (Heather and Robertson, 1996) but accurate numbers are not available. Australia is thought to have < 1000 individuals and New Caledonia <50 (BirdLife International, 2012) Threats and conservation As 90% of wetlands are now gone in New Zealand (Cromarty and Scott, 1996; Ausseil et al., 2010), habitat loss is expected to be the largest threat to bittern populations. A review of related bittern species by O’Donnell (2011) suggested that predators, poor water quality, and reduced food availability may also be contributing to a population decline. Despite the likelihood that bittern are in decline, there is currently no information regarding the extent of this decline. More research is required to understand the relationship between bittern population changes and potential threats. Breeding The cryptic nature of bitterns has resulted in a deficit of information regarding breeding behaviour. Egg laying is thought to take place from August to December, peaking in November. Nestlings are usually reported between September and February, and expected to fledge from November to May (O’Donnell, 2011). Behaviour and ecology Bitterns are extremely sensitive to disturbance. When approached they either a) try to steal away silently before they have been detected or b) adopt a still posture, commonly known as the ‘freeze’ or ‘surveillance’ pose. This stance involves standing with an erect neck and bill. It allows the bird to blend perfectly into most wetland environments, whilst maintaining good surveillance of its surroundings. If an observer continues to approach a bittern that is in freeze stance, the bird will eventually take flight laboriously, or occasionally will flatten its chest completely to the ground, effectively disappearing from view in the blink-of-an-eye. When foraging, bitterns often stalk along wetland/water edges slowly, taking prey opportunistically. In areas where prey are abundant they have been observed slowly moving towards prey items until they are close enough to take their prey in a discreet, steady manner without needing to lunge or swipe. Food Australasian bitterns are opportunistic feeders. They are thought to feed predominantly on fish; but are also known to forage on eels, spiders, insects, molluscs, annelids, crustaceans, reptiles and amphibians (Teal, 1989; Whiteside, 1989). Web links http://www.nzbirds.com/birds/matuku.html http://www.birdlife.org/datazone/speciesfactsheet.php?id=3767 http://www.doc.govt.nz/conservation/native-animals/birds/wetland-birds/australasian-bittern-matuku/facts/ http://www.iucnredlist.org/apps/redlist/details/106003767/0 http://bird.net.au/bird/index.php?title=Australasian_Bittern http://www.teara.govt.nz/en/wetland-birds/3 http://www.doc.govt.nz/conservation/land-and-freshwater/wetlands/arawai-kakariki-wetland-restoration-programme/ http://en.wikipedia.org/wiki/Australasian_Bittern References Ausseil, A.-G. E., Chadderton, W. L., Gerbeaux, P., Stephens, R. T. T., & Leathwick, J. R. (2010). Applying systematic conservation planning principles to palustrine and inland saline wetlands of New Zealand. Freshwater Biology, 9999(9999). BirdLife International. (2012). Species factsheet: Botaurus poiciloptilus.Available at http://www.birdlife.org/datazone/speciesfactsheet.php?id=3767 [Accessed 11 July 2012]. Cromarty, P., & Scott, D. (1996). A directory of wetlands in New Zealand. Department of Conservation, Wellington, 395. Heather, B., & Robertson, H. (1996). The Field Guide to the Birds of New Zealand: Penguin Books (NZ) Ltd. Marchant, S., and Higgins, P. J. (Eds) (1990). ‘Handbook of Australian,New Zealand and Antarctic Birds. Vol. 1: Ratites to Ducks.’ (Oxford University Press: Melbourne.) 1056 - 1061 O Donnell (2011). Breeding of Australasian Bittern (Botaurus poiciloptilus) in New Zealand. Short Communication. Emu. 111, 197-201 Ogle, C. C., & Cheyne, J. (1981). The Wildlife and Wildlife Values of the Whangamarino Wetlands (No. Fauna Survey Unit Report No. 28). Wellington: New Zealand Wildlife Service. Soper, M. F. (1958). A Bittern’s nest. Notornis 8, 50–51. Teal, P. J. (1989). Movement, habitat use and behaviour of Australasian bittern (Botaurus stellaris poiciloptilus) in the lower Waikato wetlands. Masters thesis, Waikato University. Whiteside, A. J. (1989). The behaviour of bitterns and their use of habitat. Notornis, 36, 89-95. Breeding ecology facts tab Social structure: Mostly solitary. Female-only incubation and brood-care (Heather and Robertson, 1996)) Breeding season: August – May, peaking in November and December (O’Donnell, 2011) Maximum number of successful broods per season Observations so far suggest Australasian bittern produce only one brood per season. However rare successful second clutches may be possible, as they have been observed in more well-studied, closely-related species (e.g. Botaurus stellaris, Mallord et al., 2000). Nest type: raised or floating platform Nest description: A platform usually surrounded by water and made from broken raupo, reeds, rushes and/or woody vegetation (O’ Donnell, 2011). Nest height above water Mean of 5 nests = 0.43m (Teal, 1989) Clutch size Minimum: 3 Mean: 4 Maximum: 6 Mean egg dimensions (mm) 51 x 37mm Egg colour: Olive-brown Egg laying dates August- December (with median records in November (O’Donnell, 2011)) Interval between eggs in a clutch (days) 24 - 48 hours (Soper, 1958) Incubation behaviour: female only (Heather and Robertson, 1996) Incubation length (days) c. 25 (Heather and Robertson, 1996) Nestling type: Altricial (Kushlan and Handcock, 2005) Nestling period: Length unknown but nestlings have been recorded from September – February (O Donnell, 2011) Age at fledging approximately 7 weeks (Heather and Robertson, 1996) Age at independence (days) unknown Age at first breeding (years) unknown Maximum longevity (years) unknown Maximum dispersal (km) unknown References Heather, B., & Robertson, H. (1996). The Field Guide to the Birds of New Zealand: Penguin Books (NZ) Ltd. Kushlan, J. A., and Hancock, J. A. (2005). Herons. (Oxford University Press:New York.) Mallord, J. W., Tyler, G. A., Gilbert, G., & Smith, K. W. (2000). The first case of successful double brooding in the Great Bittern Botaurus stellaris. Ibis, 142(4), 672-675. Ogle, C. C., & Cheyne, J. (1981). The Wildlife and Wildlife Values of the Whangamarino Wetlands (No. Fauna Survey Unit Report No. 28). Wellington: New Zealand Wildlife Service. O Donnell (2011). Breeding of Australasian Bittern (Botaurus poiciloptilus) in New Zealand. Short Communication. Emu. 111, 197-201 Soper, M. F. (1958). A Bittern’s nest. Notornis 8, 50–51.

Bitterns at Avon- Heathcote

Hi all- I am working on photo identification of birds on lower Avon River. There are at least 7 bitterns there. An eighth bird was sighted in the reeds on the lower Heathcote. This is a very signficant event with almost a fifth of Canterburys bittern population at one site. Yet I am concerned that the birds are vulnerable to predation and sighted three feral cats working the reed beds and noticed several cat predated mallards and one wounded mallard in the reeds. The Christchurch City Council has been notifed and hopefully a trapping program will be underway as most of the bitterns are concentarted in a small area. Also as the site is next to a busy highway the chance of road-kill is quite high as bitterns and cars don't mix. Also there is a Bittern conservation page on Facebook- "Bittern Conservation - New Zealand" If anyone makes any sightings or has any photos I would be interested- langlands@xtra.co.nz Regards Peter Langlands

spot the bittern ?

Spot the bittern !- photo taken today- Friday 13 th July 2012 at mouth of Christchurch's Avon River- for the first time in living memory there were three bitterns on the Avon Rivers' margin this morning . Not a bad start to Friday 13th !

The peek-a-boo bittern by Nicola Toki after an interview with Peter Langlands - Bittern Researcher 12 July 2012 Published on www.stuff.co.nz

Hands up who has been lucky enough to see a bittern in New Zealand? (Puts her hands down - with accompanying sad face.) New Zealand is a stronghold for the makatu or Australasian bittern, but even so, we only have around a thousand left. This is exacerbated by the fragmentation of their habitat and the way they are scattered across the landscape, meaning it's harder for them to find each other across wide areas, and easier for tiny populations of them to get knocked out by chance events or predators. Bitterns are masters of disguise. They have beautifully marked feathers that match their wetland reedy surroundings, and when in danger, they engage in a rather bizarre tactic of adopting a "freeze" position - standing straight and still in the raupo or reeds, pointing their bill to the sky and simply disappearing into the landscape. A friend of mine recently told me that she spent a couple of hours crouched in a wetland on the West Coast hoping to see a bittern, and when she gave up and moved away, one flew up out of the reeds next to her. The strong legs of the bittern mean they eject themselves out of the reeds like a jack-in-the-box so I imagine she got quite a fright! If you haven't seen a bittern, you may have heard one. Like the kakapo, they "boom". The males blow themselves up like a bullfrog and make a low-resonance booming noise that can apparently be heard for up to two kilometres. Given the bittern's incredible camouflage, the booming is often the only way to know that they are present in an area. If you're keen to find out if you have bitterns in your 'hood, listening out at dawn or dusk from now until November is a good way to find out. Bitterns are the apex predator of the wetland, so if your wetland has bitterns it's a good sign you have a healthy, well-functioning ecosystem. The bitterns eat young eels, fish, frogs, freshwater crayfish and insects. Where did all the bitterns go? In the space of 150 years, New Zealand has managed to drain and destroy 90 per cent of our wetlands, which are home to a huge range of native wildlife, including bitterns. Add in the mix the impact of predators and the odd roadkill death and you've got a recipe for a declining population. It's not all bad news though. Occasionally people give bitterns a helping hand, as in the case of Bitty the bittern, who spent a week or so in the Whangarei Bird Rescue Centre, who was fed, housed and then released back into a wetland to get on with his life. Or the story of the young bittern nestling who wandered into a chookhouse and spent three months living alongside his chook "mates".

Botaurus poiciloptilus Status_ne_offStatus_dd_offStatus_lc_offStatus_nt_offStatus_vu_offStatus_en_onStatus_cr_offStatus_ew_offStatus_ex_off Summary Classification Schemes Images & External Links Bibliography Full Account Taxonomy Assessment Information Geographic Range Population Habitat and Ecology Threats Conservation Actions View Printer Friendly Taxonomy [top] Kingdom Phylum Class Order Family ANIMALIA CHORDATA AVES CICONIIFORMES ARDEIDAE Scientific Name: Botaurus poiciloptilus Species Authority: (Wagler, 1827) Common Name/s: English – Australasian Bittern Assessment Information [top] Red List Category & Criteria: Endangered C1 ver 3.1 Year Published: 2009 Assessor/s: BirdLife International Reviewer/s: Garnett, S., Butchart, S., Bird, J. Contributor/s: Herman, K., O'Donnell, C., Blyth, J., Tzaros, C., Bell, B., Garnett, S., Holmes, T., Miskelly, C., Loyn, R., Wakefield, B., Watson, D., Burbidge, A., Jaensch, R., Barré, N., O'Connor, J., Sherley, G., Ford, H., Christidis, L. Justification: This species is listed as Endangered because it has a very small and rapidly declining population owing to loss and degradation of its wetland habitats. Urgent action is a priority to halt declines in Australia. History: 2008 – Endangered 2006 – Endangered 2004 – Endangered 2000 – Vulnerable 1996 – Endangered 1994 – Endangered Geographic Range [top] Range Description: Botaurus poiciloptilus occurs in the wetlands of southern Australia, New Zealand and New Caledonia (to France). In Australia the population is now estimated to number not more than 1,000 mature individuals15. Consecutive atlas censuses in Australia have shown a marked decrease in reporting rate; the species was recorded in 260 10-minute grid squares in 1977-1981, 142 grid squares in 1998-2003, and just 61 in 2003-200816. The declining reporting rate was particularly pronounced in the Riverina (63%), Tasmania (>90%), and south-west Australia (>90%). This decline in reporting rate is thought to represent a genuine population decline over the period. In Australia, most birds are in the Murray-Darling basin and adjacent coastal areas. In Western Australia, the population was estimated to contain up to 100 pairs in 19807, but it is now much reduced, with the largest concentration in the Albany and Lake Muir wetlands. There have been no confirmed records from the Swan Coastal Plain since 1992 and surveys conducted in 2007 and 2008 found that half the wetlands that supported the species in 1980 now retained no suitable habitat17. There are now only occasional records from Queensland5 and there appears to have been no great influx to remnant wetlands after the recent drought, as might have been expected if they were more common inland. In South Australia, breeding is confined to the south-east, however, loss of suitable habitat at Bool Lagoon, arguably the key site in Australia for this species, and other wetlands in the area due to changes in regional drainage, has probably had a large impact in last 10-20 years13. It is now known from just one site, Hirds Swamp, in Victoria18. In Tasmania the species is now recorded from only handful of sites and several of the major lakes that it once occupied have been dry for some years. In New Zealand, the estimated population was between 580-725 individuals in 19806; numbers may be greater, given the lack of targeted survey work, and the large size of suitable swamps9. In New Caledonia and Uvea, there have been just two recent records of single calling males, and the population is not thought to exceed 50 individuals1,3. Countries: Native: Australia; New Zealand Present - origin uncertain: New Caledonia Range Map: Click here to open the map viewer and explore range. Population [top] Population: In New Zealand, the estimated population was between 580-725 individuals in 1980 (Heather and Robertson, 1997). The population on New Caledonia is not thought to exceed 50 individuals. Following apparently rapid declines, the Australian population is now thought to number fewer than 1,000 mature individuals (R. Loyn in litt. 2008). Population Trend: Decreasing Habitat and Ecology [top] Habitat and Ecology: It has fairly specific habitat preferences, preferring shallow, vegetated freshwater or brackish swamps where there is a mixture of short and tall emergent sedges and rushes4. It has been recorded in paddies in the Murray Darling basin, but it is not thought to use such habitats for breeding18. It usually lays four eggs. It feeds, mostly at night, on fish, eels, frogs, freshwater crayfish and aquatic insects6. The population seems to increase rapidly in good years and decline rapidly in poor ones12. Systems: Freshwater; Marine Threats [top] Major Threat(s): In Australia and New Zealand, the main threats are wetland drainage for agriculture, as well as changes brought about by high levels of grazing and salinisation of swamps2,4,5. In Australia, the species appears able to adapt to the availability of ephemeral wetlands, but is likely to be particularly sensitive to the destruction of drought refugia. Loss of these habitats may explain its decline in Western and South Australia5. The Murray-Darling basin, a former stronghold of the species, has suffered consecutive droughts in recent years and over-extraction of water is an ongoing problem14,15. Shooting and flying into powerlines are additional contributory causes2, but hunting pressure is very low11. Conservation Actions [top] Conservation Actions: Conservation Actions Underway In Australia, Bool Lagoon and Lake Muir are managed specifically for the species5. In Australia, recent initiatives by the Threatened Bird Network to survey Painted Snipe Rostratula benghalensis australis will contribute to the information on the distribution of this species10, 18. Conservation Actions Proposed Complete field surveys to determine current global distribution, status and key sites for conservation1,5,8. Develop methods for assessing population trends5. In New Zealand, determine factors that may be limiting populations8. In New Caledonia, obtain legal protection of representative, low altitude habitats1. Protect remaining sites against drainage or salinisation. Rehabilitate former breeding sites5. Citation: BirdLife International 2009. Botaurus poiciloptilus. In: IUCN 2011. IUCN Red List of Threatened Species. Version 2011.2. . Downloaded on 11 June 2012. Disclaimer: To make use of this information, please check the . Feedback: If you see any errors or have any questions or suggestions on what is shown on this page, please fill in the feedback form so that we can correct or extend the information provided

Request for bittern sightings in Canterbury 2010-2012

Hi all - yes I am still working on bitterns- data sets are being analysed on a national level at present by myself and I understand DOC- so to all who contributed sightings up to 2010- thanks . I will be releasing some informal reports this year and am working on a scientific paper on an analysis of bittern mortality-injury records in New Zealand.DOC updated their web page last year with a threatened species profile on bittern which Colin O'Donnell and myself contributed to - about time given the Nationally Threatened status of the species! At present I am keen on any bittern records ( not already sunmitted to me) from Canterbury in the last two years ( back to June 2010) for a research report I am working on at present. All sightings will be acknowledged. Thanks Peter

An update from North Island bittern researcher- Emma Williams

Last year we found that our recording devices compared favourably with observers listening for bittern in the field. As a result of this, we are now looking at how they can be used to monitor bittern populations on a national scale.

Our objectives this season are:

At Whangamarino wetland

To repeat the baseline Whangamarino bittern survey with the automatic recorders. This should
• provide a firm baseline for future monitoring
• give us an idea of the feasibility and issues associated with deploying a large number of recorders at one time
• test our revised field protocol for monitoring
A low density wetlands nationally

To sample bittern calls from sites with lower densities of bittern to try and see if the monitoring protocols work in such areas. This work is taking place mainly in the Waikato, Manawatu and the East Coast, at wetlands with <8 bitterns.

If anyone is interested in getting involved or knows of a good spot worth investigating for bitterns, feel free to get in touch with either of us.

In the meantime, we will keep you posted with how it all goes and look forward to hearing about everyone’s bittern sightings and booming reports.

Contact: Emma Williams (bitternwills@gmail.co.nz) or Colin O Donnell (codonnell@doc.govt.nz)

Regards

Injured bittern rescued but can not be returned to wild

Link
http://www.stuff.co.nz/manawatu-standard/news/5188268/Vets-take-Boris-under-their-wing

Bitterns in the environs of Brooklands Lagoon-

The following is a recent report (-120511) from Christchurch City Council ranger/ornithologist- Andrew Crossland-


Bittern set to be the big winners from the CHCH earthquakes

3 bittern sightings in less than a week in the environs of Brooklands
Lagoon have made me take stock of what a major turn of fortune the CHCH
earthqukes have been for the local conservation of this species.

Elevated river levels (considered to be permanent) have flooded riparian
margins all the way along the Styx River and Kaputone Stream in NE
Christchurch, turning many, many hectares of willow/blackberry infested
riverbank and dry ex-river channels into well-watered riparian wetlands.
The 86 ha Styx Rivermouth wetlands which were essentially tidal
saltmarsh and rivermars prior to the quakes has now expanded by 10+ ha
with large springs flooding a large area of rank grass-covered wasteland
which since the Sept quake has rapidly begun to infill with raupo.
Bittterns have already discovered this habitat, which within 2-4 years
will hopefuly be a vast raupo swamp offering plenty of breeding habitat
for swampbirds.

AC

Russia's 'kiwi' came from closer to home
KIRSTY JOHNSTON Last updated 09:50 11/05/2011
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REED ALL ABOUT IT: A Eurasian bittern blends in nicely in its marshy habitat.

BNZ Save the Kiwi Trust A BITTERN DIFFERENT: A kiwi chick. Getty Images MASTER OF DISGUISE: An American bittern mimics a reed by pointing its beak skywards.
The story of a kiwi bird gone rogue in a Russian city has turned out to be a case of mistaken identity.

Russian media had reported that the kiwi was found in a garden in the port city of Sochi, where it had been hiding out for at least three days.

Speculation was rife as to how the kiwi arrived in Russia, with some believing it had been smuggled on a cruise ship.

However, after viewing a picture of the bird yesterday, Zoologist Alexander Kornilov instead identified the bird as a common bittern, Russian BBC reported.

Bitterns, which are found throughout Europe, North Africa and central Asia, migrated through the region of Sochi each spring, Kornilov said.

"Probably one of the birds hit the wires, damaged the wing and so she stayed in Sochi. The situation is quite common," he said.

The Department of Conservation, which had been investigating the reports, said it wasn't surprised by the result.

It warned yesterday that similar reports had turned out to be hoaxes.

However, the mistake may have been a genuine one.

Russian news site Pravda said the bittern in the Sochi garden probably would have resembled the Kiwi in appearance, as they typically moved along the ground while in the park.

Like kiwi, Bitterns are shy, secretive and more likely to be heard than seen, according to a BBC description.

The plump heron-like birds are described as having "subtle brown plumage" which blends almost perfectly into its reed-bed habitat.

Even when frightened, the bittern stands perfectly still pointing its neck and bill skywards, to look just like a reed stalk.

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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).

As another season ‘Bitterning’ at Whangamarino wetland comes to an end- by Emma Williams

How do you monitor a bird that is adamant it’s a blade of grass?!
Emma Williams
As another season ‘Bitterning’ at Whangamarino wetland comes to an end, it’s time to wash the mud off the waders, empty the water out of the gumboots, and go back to the desk to work out what on earth was going on.
This was our second season of research out in Whangamarino. Our objectives were to develop a monitoring method for bittern and it’s not easy trying to monitor a bird that spends the majority of its time impersonating grass in inaccessible bogs. Yet, as only 10% of their original habitat remains today, it’s never been more important to know what’s happening with the bittern population in New Zealand.
Thankfully, male bittern make a distinct, deep ‘booming’ call during the breeding season, which we are hoping will prove useful as part of a survey method. Unfortunately, the calling-rate of bittern seems to vary greatly over time and between stations. This makes it tricky to detect trends in bittern populations using call counts alone. For example, this season at Whangamarino wetland, 234 ‘booms’ (per 1.5 hours) were recorded at one station in October. Yet, only one month later, no bittern were recorded from that same listening post. Did the bittern move or do they just have fewer reasons to call?
Hopefully we’ve got enough data this season to get some idea. In 2009, Lynette Plenderleith and I went hard out trying to see if bittern really are as crepuscular as everyone suggests. The evenings looked good, with a beautiful peak in calling-rates appearing about half an hour after sunset. Mornings were not so clear cut, with lots of sub-peaks leading up to sunrise. After several mornings of dragging ourselves out of bed at 2am, only to discover that bittern were already up and booming, we concluded that something else was going on. One morning we both came back adamant it was the moon. This has been proposed before by others, such as Philip Teal and Jono More. Teal suggested that the moon was somehow linked to bittern food sources, like the movement of whitebait. Who knows though, may be it is just easier to advertise yourself to the opposite sex when you can see the female, she can see you, and most importantly, you know where her mate is lurking.
So this year (2010) we were back out there again, trying to get more information. Unfortunately, Lynette couldn’t make it - she decided frogs were her passion, and the temptation of a full scholarship and PhD in Australia was just too much...so she passed her waders onto Elise Verschoor, and the swamp fever continued.
The objectives of this season were slightly different. We wanted to know more about the extent and cause of variability in calling-rates. We also needed to get around some of the issues that were limiting our sampling regime. Fundamentally, that we couldn’t sample more than two sites at once, and large sections of the inner wetland remained un-sampled (some places just took us too long to get to without a boat, and others you wouldn’t come back from, especially in the dark!). To solve this, Graeme Elliot and Stuart Cockburn lent us some of their bird recorders and we were able to directly compare MONO and STEREO recordings with results collected from an observer in the field.
The results so far
Its early days and there are still recordings to process, but things look promising. Recorders appear to be as reliable for detecting ‘booming’ bittern as a person physically in the wetland. In fact more reliable - at least with recordings you can ‘pause’ to write when multiple bittern boom at once.
It will take us a little longer to process the data regarding the variability in calling-rates though. What we do know already is that bittern call-rates peaked in October as predicted. Also, contrary to expectations, we detected a second peak in one small area of the wetland (the causeway). Although not common, this second peak has been observed before with the Eurasian bittern (Botaurus stellaris) and is thought to be associated with males advertising feeding areas to fledglings or females becoming available again after nest failure . So, is it a coincidence that most of the ferrets the Department of Conservation caught during their ‘mark-recapture’ trials were along the causeway this year? Who knows? The research continues, and we still have a long way to go...but we will keep you posted...

Update from Colin O'Donnell- on bittern from DOC's work

Progress with developing monitoring techniques for cryptic swamp birds (bittern, fernbirds and rails)
The Department of Conservation has begun developing monitoring methods for swamp birds over the last year. We require robust methods to map distribution, identify critical habitats and monitor response of swamp birds to wetland management. Methods need to be sensitive enough to detect significant population changes within relatively short timeframes so that management can be adaptive. So far we have developed a national database for Australasian bittern, reviewed impacts of introduced mammalian predators on wetland birds and trialled automatic bird call recorders for recording bittern. Bittern usually call at night, with peaks at dawn and dusk and live in some deep swamps, so they are challenging to monitor using conventional means - so using auto recorders for inventory and/or monitoring is a promising possibility. In field trials at Whangamarino wetland in the Waikato region the recorders were excellent at recording bittern calls (up to 50 boom trains per 15 minutes) , with the recorders generally performing as well as human observers in our initial trials. Work is continuing on identifying the best time of year and night to monitor numbers and designing the sampling methods needed.

Contact: Colin O’Donnell (codonnell@doc.govt.nz)


Cheers
Colin

Dr Colin O'Donnell
Ecosystems and Species Unit
Research and Development Group
Department of Conservation — Te Papa Atawhai
VPN: 254985 | M: +64 276602476

Conservation for prosperity Tiakina te taiao, kia puawai
www.doc.govt.nz

Key bittern locations in the South Island

Hi all- the map attached some key sites (n=13) where bitterns currently occur within the South Island.
Click on map thumbnail to expand the image

If any one wants any detailed maps within each site then please email me
-Peter Langlands
langlands@xtra.co.nz