Wetlands need water to function and here we are again engrossed in another dry summer with severe drought conditions being experienced in a number of regions.

This adversely impacts on water levels in our wetlands and the biodiversity they support. We cannot ignore that climate change is having an effect.

What can we do about it?

DU needs to continue its good work with protecting and restoring wetlands, increase our membership, maintain the excellent relationship we have with many partners in the wetland conservation area, and expand our fund raising efforts. These are all key areas
which the DU Board will be addressing over the next 12 months.

The dates for this year’s AGM are at the Distinction Hotel, Palmerston North, for the weekend of Friday July 31 to Sunday August 2, 2015.

Look forward to seeing you all there.

John Cheyne

 

Last issue I introduced Australasian bitterns, a rare, secretive wetland bird that often lives within a stones’ throw of people’s houses – yet only the lucky few who spend time in wetlands know this species exists!

As our  bittern is the rarest in the world, we have  several reasons to be concerned about the population here in New Zealand.

 

In the last DU issue I discussed several threats known to limit bittern populations overseas - threats that are unfortunately also present in New Zealand. These threats include habitat loss (here in NZ this loss amounts to a shocking 90 percent!), introduced predators, modified water levels, poor water quality and inconsistent food availability. Unfortunately, despite knowing this, we still have little information about what’s happening with the bittern population here in New Zealand.

This is mainly because bitterns are almost impossible to find and study due to their camoflage plumage and elusive behaviour. Not being able to find this species also means conservationists can’t tell if their efforts to save the species are working.

 

To solve this problem we’ve been developing several monitoring methods that can be used to detect and count breeding male bitterns. This year we wanted to measure how well these methods work.

To do this we needed to catch and ‘mark’ as many male bitterns  as possible on Lake Whatuma, in Central Hawke’s Bay. We knew this would be tricky because to-date few bitterns have been caught.  However, as a team we collectively had several years of bird catching experience using a variety of methods…knowledge of two methods that had been used successfully to catch bitterns overseas…an ability to adapt as we went…and a ridiculous amount of dogged determination… And it worked!

Since September we’ve been able to catch six  male bitterns at Lake Whatuma. We caught all six birds by luring them into cage traps using a combination of calls and mirrors.

 

Playing bittern booming calls within a bird’s territory worked because it tricked the resident male into thinking that a rival male is challenging it. The resident male tries to creep up on this fake rival male intending to see it off. Eventually it sees its own reflection in the back of the cage trap, which it mistakes for the intruding bird, causing it to enter the trap. As soon as the resident male steps on the treadle plate inside the trap, it’s weight releases a catch, dropping the cage door shut, and capturing the bird.

 

Once caught, we banded each bittern with a metal M-band to make them uniquely identifiable in the hand. 

We also attached the radio transmitters provided by Ducks Unlimited sponsorship to help us locate and  identify the bird even when it was hidden from  us in the thick vegetation.

 

Before releasing the bird we weighed it, took a range of measurements (such as length of tarsus, bill, wing and tail), and some photos of its bill and feather patterns.

Photos and measurements can be used to crudely determine the health of the bird and as a general guide to help us confirm its age and sex. Each captured bittern was named in the honour of a deceased crooner – so by November we had caught Barry White, Bing Crosby, Tama Tomoana, Prince Tui Teka, Howard Morrison and Elvis Presley.

 

Once we’d finished processing each captured bird we released them back into their territories.

After that we regularly located birds using the signals emitted from their transmitters. Locations of marked bitterns were plotted to map their territories. We also checked where birds were located during our monitoring sessions and noted if a bird called during monitoring periods, and for those birds that did call we looked to see if observers had succeeded in detecting them. 

 

The results of our monitoring trial are still being analysed but preliminary results already show that breeding male bitterns have high site fidelity during the breeding season, meaning they always boom from the same area.

This is good news for our monitoring methods as it allows us to assume that booms heard at the same location at different times during the breeding season were produced by the same bird.

 

There was one exception. Bing Crosby, a bird caught in the northern end of the lake, permanently left his territory in October (midway through the breeding season). However, we have reason to believe that Bing was not as popular with the opposite sex as his namesake – and therefore does not count as a breeding male. Indeed we suspect he left the lake because he was single and  wanted to try his luck at wooing a female  elsewhere. There are several reasons why we suspect this. Firstly, the quality of Bing’s booming, something that’s associated with mate attraction, dropped steadily throughout the breeding season. This was not observed with the other marked males. Secondly, we had fewer observations of unmarked non-booming birds (females?) within Bing’s territory compared to some of the other booming males. This causes us to suspect that any visiting females were not staying for long. 

Thirdly, in the final days leading up to Bings disappearance he became more transient, often appearing in places that seemed well outside of his usual territory.

 

For example, two days before his disappearance he was found in the heart of his neighbour’s territory cavorting with two unmarked non-booming bitterns. His neighbour was booming within 100 metres of these liaisons - A final desperate attempt at securing a Lake Whatuma female perhaps??

 

Finally, after Bing’s disappearance we searched his territory for evidence of nest  attempts and were unable to find anything  to suggest he had attempted to mate with a female. We believe he was a single male trying his luck, but still can’t say this with certainty because many of the birds interacting with Bing were still unmarked and the sex of bitterns is difficult to determine from plumage alone.

Still, if we had not had the transmitter on him we would have never known that about these behaviours. Interestingly we observed similar transient behaviours with the other five marked bitterns. Although for them these observations occurred much later in the season and coincided with the time when we were expecting bittern chicks to fledge.

At this time of year (December/January), it makes sense for males to be more mobile, as chicks are supposed  to be relatively independent after fledging,  leaving few reasons for males to invest time and effort in maintaining their territories.

 

As you can see we still have much to learn about bitterns, their needs and behaviours. However, just in these last six months, through the use of the transmitters provided by Ducks Unlimited, we’ve been able to associate some of our observations with individual birds allowing us to put these observations into greater context.

 

All six of our marked bitterns have now left Lake Whatuma – again something we did not (and could not) have known would happen if our marked birds were not carrying transmitters.

We plan to continue following these six bitterns over the next six months. Hopefully the more we learn about them, their movements and habitat requirements, the more these observed behaviours will start to make sense.

It is looking like another record year of ducklings being produced with hopefully 39 being released. Peacock Springs with 18, Mt Bruce with 16 and Orana with five. Could have been more but you can never count your ducklings till you have them on the ground.

 

It is really great to see more ducklings produced each year and could be more if all the breeders had new pairs.

 

This facility has been build at the Tongariro National Trout Centre in some of the trout runs. I did go up earlier in the year and with helping Andrew Smart did the shaping of what you can see in the photos.

 

There were 12 ducks in the enclosures doing well and a lot flying around and diving into the water. Another 11 birds were put in the other side.

 

 

This new facility will make it easier for  North Island breeders to send their birds there, rather than the South Island for hardening.

 

On December 4 last year I took six birds, that came from Peacock Springs, up to the Trout Centre for the opening of the Hardening Facility by the Minister of Conservation Maggie Barry and the CEO of Genesis Albert Brantley, as this was a joint project between Genesis and the Department.

 

At the opening there was a welcome from Haukainga for the visitors and then a welcome from Mihi/Whakatau to manuhiri/ visitors - Ned Wikaira followed by a reply on behalf of the visitors -Pou Tairanghau. We had refreshments by the new facility and heard speeches from Albert Brantley, Maggie Barry and then the National Whio Recovery Group Leader Andrew Glaser.

 

The Minister and Genesis CEO then cut the ribbon to declare the facility open. This facility was funded by Genesis and the Department of Conservation.

 

The birds were released into the new enclosure which was great.

 

Peter Russell

Whio Captive Co-ordinator  

 

Freedom at last for the first 17 whio released this year into the Little Maketawa Stream at Egmont National Park. “It went well,” said Peter Russell.

 

A special karakia for all the birds was conducted by Sandy Parata from Ngati Runaui, before the birds were released.  And they were really happy to get into that water.

 

Mr Parata has been actively involved in the Egmont National Park whio reestablishment programme. 

 

Emily King, Senior Biodiversity Ranger  with DoC said “The success of our project would not have been possible without the support of the Central North Island Blue Duck Conservation Trust as they have been very committed and actively involved in the Egmont National Park whio reestablishment programme.”

 

There were 16 Whio ducklings hatched this  season at Mt Bruce. One of our team, Tara, has taken this delightful photo of the latest clutch of whio to hatch at Pukaha this season. These ducklings spent a few weeks here and then were sent to a ‘hardening unit’ at Turangi to ensure that they will be ready for release. Whio live in fast running rivers, so if the ducklings aren’t ‘trained’ before release to get used to the fast water they have a tough time getting used to life in the wild. With an estimated 2500 of these ducks left in the wild, 16 new ducklings from Pukaha is a great result and one we are proud of. Did you know that the whio is on our $10 dollar notes? For more information about whio visit www. whioforever.co.nz More white kiwi Late February, one of the DoC rangers who  regularly monitors the kiwi at Pukaha Mount Bruce found not one, but two white kiwi in a burrow there. This brings the number of white North Island Brown kiwi to be hatched at Pukaha since 2010 to five. The burrow the white kiwi chicks were found  in belongs to the father of the three other white kiwi previously hatched there. 

There is a one-in-four chance that chicks produced by the pair will be white, and as kiwi partnerships have been known to last for decades it’s not completely unexpected. But to Pukaha Mt Bruce staff it still feels as if we won the The two chicks were given a health check by  DoC and Pukaha staff who confirmed the pair were in good health. The chicks have started to feed by themselves and the decision was made that they would remain in the reserve rather than be brought into the nursery. Having kiwi hatch and survive in the wild is a great indication that the thousands of dollars each year spent on predator control in the reserve is paying off. Any kiwi chick hatching at Pukaha is a truly special occasion, but the white kiwi are currently unique to Pukaha. Staff will regularly check the two chicks, as their transmitters need to be re-sized regularly as they grow. Helen Tickner General Manager, Pukaha Mount Bruce