Super User
Monday, 04 September 2017 11:58
On the Scent - Bittern
On the trail
It’s a beautiful morning on Lake Whatumā. As the last of the fog lifts and disperses, leaving the lake’s clear water exposed, Kimi and I float along the edge of the western shore quietly in our kayak. We’re looking for bittern nests and listening for the tell-tale bubbling call of chicks.
Nearby, peering out of two separate maimais are the heads of Finn McCool and Bernie Kelly. They’re watching careful for any signs of movement within the Raupo – an important job. Kimi and I can’t see more than a few metres in front of us as we move through the Raupo so we always need ‘spotters’ to detect the birds that are present but try to sneak away from us.
Suddenly, Kimi’s black Labrador nose begins to twitch. She’s picked up some scent. Her tail flicks up and begins to bounce from side to side as she reaches forward across the kayak. I slip off the kayak giving her permission to do the same. It is at this moment that we transform into our swamp alter egos. Kimi becomes an elegant torpedo - her otter-like tail propelling her beautifully through the water, until she silently disappears into the Raupo.
And me? Not so much.
Flushing
My transformation is somewhat less fortuitous. Knee deep in mud, one foot already stuck and water up to my waist - my movements are best described as cloddish and ungainly. I slosh awkwardly after her trying my best not to sound like a heffalump bombing in a swimming pool. As I enter the Raupo, my radio crackles and Bernie announces that a bittern has flushed south of our location. We can never be sure of the sex of a bittern when we see one, but there are a few tell-tale signs that give us a clue.
Firstly, females are noticeably smaller than males, and secondly, in the case of Lake Whatuma, we know that none of the females are wearing radio-transmitters (yet!). Both Bernie and Finn carry radio-receivers. These devices detect the pulse-like signals emitted from any bird that’s been caught and still carries a Ducks Unlimited transmitter. If a radio-signal is detected, Finn and Bernie can identify the bird and follow its movements even if they can’t see it in the thick Raupo – so when a relatively small bittern flushes and they don’t get a signal on their receivers they know it’s likely to be a female.
Found
The excitement in Bernie’s voice tells me this bird fits this criteria even before his words confirm it. Another female is great news. We’ve been searching bittern territories at Lake Whatuma for females and nests for a while now. We started unobtrusively by watching over known territories in October for something known as a ‘female foraging flight’. These flights are supposedly undertaken by females when they leave the nest to find food, a behaviour they have to do regularly because the males don’t feed them or the chicks. Such flights are noticeable and have enabled researchers to find nests overseas. By November, we have only witnessed a handful of these flights, and after investigating them further none suggested the presence of a nest. This surprised us. In previous years we’ve found nests by accident and all of them were (or would have been) at chick stage by November.
It was time to up the ante…and go in with the dog. Since November we’ve swept every known territory on foot looking for evidence of nesting. Up till now, and with the help of spotters like Bernie and Finn, we’ve been able to find at least four small unmarked birds (females), but none of them appear to show any interest in breeding. This latest bird would be the fifth. Bitterns are polygynous, meaning males often have more than one female. So it’s reasonable to expect up to five females to every male. To only find five on the whole lake – a site with at least twelve booming males – is somewhat concerning. If not down-right depressing.
To add to our concerns – the five males that still carry Ducks Unlimited transmitters at Lake Whatuma have been very unstable in their territories. They started off well, with all five returning to the lake in August to boom as usual and fight over the usual patches of real estate. Yet by October only two appeared to have claimed a Raupo patch. The others had spent all their time interfering with their neighbours before leaving to try elsewhere. Why are they not finding what they need at L. Whatuma?
So when Bernie confirms a fifth female. I think we can be forgiven for thinking we’d won the lottery. He immediately directs me southwards towards where the bird came up...but Kimi has different plans and starts heading northwards into the breeze. I pause for a second. On one hand I have a confirmed sighting to the south. A rare opportunity to reward the dog on fresh scent and a possibility that there was a nest nearby. On the other hand my dog clearly thinks she’s onto something better, and as I can’t be sure what the dog nose knows and John Cheyne is always telling me to ‘always trust your dog’…I decided to abandon the sterling advice of the spotter and follow Kimi’s lead.
I wasn’t disappointed. It took us awhile to find the four perfectly formed olive eggs that were tucked away on a carefully constructed platform in the thick Raupo. We think the nest belonged to the same bird that the spotter saw. Kimi has been trained on feathers and the live bird’s scent, and in this case the wind would have been wrong for her to detect the flushed female. Instead we suspect that the female moved south to evade us as we entered the Raupo. Kimi hit its scent track and was able to follow it back through the vegetation. It was definitely a team effort requiring all parties - the spotters, dog and handler.
Finding Nests
There are several reasons why we’re particularly interested in finding nests this season. We have little knowledge of how successful bitterns are in breeding and whether chicks survive to adulthood. Nests are notoriously difficult to find and this is part of our problem. To date we’ve had great success in developing methods for monitoring male bitterns (through their conspicuous booming call) but have no means for detecting females and chicks. Yet it’s the females and chicks that are our capacity to save the species. Just like money in the bank, the more we start with, the greater the capacity to grow our fund (or bittern population). One male can fertilise several females, so it’s the females that limit the size of our deposit. The more eggs she lays the higher the interest rate, and the more chicks that survive the greater the deposit in the following year.
…and of course to achieve this you have to prevent your significant other from hammering your credit card (prevent threats) in the meantime – this is tricky for bitterns as we’re still working out how many we’ve got, who’s hammering the bittern credit card and how much they’re spending…and there are so many potential spenders out there i.e. predators, poor water clarity, fluctuating water levels, poor food availability. We have many reasons to believe our bittern credit card is out of balance. In the last 12 months five starving nestlings have been found by members of the public right in the heart of urban areas – two females in Christchurch, and two males and a female in Tauranga - unusual behaviours for a secretive wetland specialist species. What happened to the parent that caused these birds to wander? Why were they nesting near to such accessible, high-disturbance areas in the first place? All five birds went into captive care and four survived to be released later in the year with healthy weights. We followed these birds post-release using Ducks Unlimited transmitters. To date two have died of starvation, one is missing – leaving a lone female surviving in Tauranga as our starting deposit.
Extinction Looms
As recently as 2010, surveyors at Whangamarino wetland – a site touted to be the national stronghold for bitterns – regularly recorded 50 + bittern calls within 15 minute long surveys. The number of birds calling could be as many as 12 individual birds per listening post and there were 40
listening posts – that was a lot of noise and a lot of birds. So many that observers regularly complained that they couldn’t keep track of them all.
listening posts – that was a lot of noise and a lot of birds. So many that observers regularly complained that they couldn’t keep track of them all.
Sadly these days are gone. Now the same locations are eerily silent, and observers are lucky to find seven birds across the whole wetland. The Australasian bittern is no longer Nationally Endangered. It is now Nationally Critical - the same threat classification as Kakapo – and the last threat classification before Extinction. The clock ticks…all year around multiple threats hammered away at the bittern credit card…and once a year there’s a short opportunity for bitterns to make their deposits. …how much longer before the balance turns red?
Emma Williams
Published in
Issue 170
Monday, 04 September 2017 11:56
Cajun Capers
From New Zealand it was easy over the internet to book some days duck shooting and fishing. However the doubts begin to creep in when you travel all the way to the “Great Wetlands of the South” in this case Louisiana, USA.
The Judge and I travelled to New Orleans by car starting from Dallas, then down the only road that leads into the most southern of the Louisiana marshes the road ending at Venice. The trip down the road had been a revelation in itself, six years after Hurricane Katrina with scars still visible where houses had been washed away, the rebuilding was impressive with all the houses and even a new high school built 18 feet off the ground.
Katrina had almost wiped Venice off the map, but rebuilding had given it a go-ahead feel and our accommodation was like everything else, built 18 feet up in the air. At 5am in the morning waiting, for our guide who was fashionably late, it was a dark and lonely place. The only other person we had seen was the cook at the bar cum restaurant who had made us a breakfast sandwich when she opened at five.
Eventually a bearded young man turned up towing a flat-bottomed duck boat. Yes, he was our guide and we should get in. Winston Churchill once described the English and Americans as two people divided by a common language, with this guide it was more of an insurmountable gulf than a divide. Suffice to say he thought we talked funny! From our part he was almost unintelligible.
The trip through the wetlands was interesting in pitch dark with no lights. We either went flat out or with alarming severity dead slow. With dawn breaking, the boat slowed again and our guide started throwing out decoys. This must be the spot we surmised. After going in circles for a few minutes we eased into a slot cut in the reeds, a thin screen of stalks kept us hidden from the ducks. “Load up!” came the command from our intrepid guide. Loaded I looked up to see a duck set its wings to come into the decoys, our guide had his head down looking at his cellphone, so I shot it. Our guide exploded from his seat demanding to know “what **** **** *** was I doing?” I pointed out I had just shot a gadwall (type of duck), which was now as dead as the proverbial dodo and was drifting away on the current.
This got a lecture from our guide which when condensed amounted to us only shooting when he said to do so. About an hour later I enquired if we might see any more ducks at this spot as apart from the one I had shot we had not seen another. Our guide explained that he was mystified by the absence of ducks as he had shot limits from this very spot every day so far this week!
The Judge at this point went very quiet. I asked if we had a plan “B” as it was not a happening thing where we were. With some muttering our guide started the engine and backed us out of the hide. We helped pick up the decoys and the gadwall I had shot which was hung up on a branch touching the water some hundred metres away from the hide. We were soon speeding through the marshes. In the daylight they were pretty amazing, vast impenetrable forests of reeds occasionally a few trees far in the distance surrounded by reed, narrow channels which suddenly opened up to vast expanses of open water. Almost unbelievably, some of the areas were in private ownership and the duck hunting rights to those areas are fiercely protected. And almost more amazingly, oil pipelines ran from offshore platforms through the marsh to holding tanks many miles inland with marker posts every time they crossed under open water, and there were a lot of them. Birdlife was patchy; on open water areas there were sometimes a flock of birds, spoonbills, pelicans, wading birds and most importantly ducks. They say there are 735 species of birds, fish and mammals that use the Louisiana wetlands.
We arrived at a lagoon, which was open to the sea on one side although the sea was probably a few miles away, but I could just see the white water from the waves breaking over rocks or a sandbar. Out went the decoys again and we slipped in between two screens of reeds growing in the middle of the lagoon hundreds of yards away from any cover. This time we were in the right place as there were ducks trading around.
Our guide started calling, it went something like, quack quack quack, “Keep your head down,” quack quack, “I said keep your head down,” quack quack “KILL’EM.” At which point we were supposed to leap up and shoot the ducks, the problem was that with our heads down when we got up to shoot we had no idea where the ducks were, if they were directly in front no problem but if they were to the side or behind us by the time we turned to shoot they were already out of range. Added to that a Cajun yelling “KILL’EM” at the top of his voice flared the ducks before we even had a chance to stand. This happened a couple of times with the inevitable lack of success, the next time our guide called the ducks in range after yelling “KILL’EM” he promptly fired his shotgun in the direction of the ducks.
Enquiring if he was shooting his own birds, he replied to the effect that he was shooting our limit as if he didn’t we would be going home empty handed. The Judge, at this point suggested that our guide might care to indicate just where the ducks were before he yelled “KILL’EM.”
He pointed out the positions of a clock – 12 o’clock in front, 6 o’clock behind, 9 o’clock to the left and 3 o’clock to the right, pointing up he said high, pointing down low. Really the morning had just reached a new low, at least I thought it had, but I was wrong. While we had been discussing how to tell the time some teal had dropped in and were sitting in the decoys about 40 metres away. “Kill em” said our intrepid guide “NO way “, said I, “They are on the water”, “Don’t matter,” says our guide. “Th’re trash birds and it is legal to sluice them on the water.” The teal had at the sound of our raised voices had the good sense to flock off.
To be honest after that my heart wasn’t in it, we scratched down enough ducks for two limits with our guide shooting most of the time. The Judge not to be out done was faster than a yelling Cajun and shot well including a beautiful Bald Plate American Widgeon, in full breeding plumage, which our guide informed us was his, as it was the best he had ever seen.
Not being the most intelligent human being I had ever met, our guide had forgotten to count the gadwall I had shot first thing and we were one bird over our two limits. One of the birds was deposited at the bottom of the decoy bag incase we met the warden and we were off back to the dock in time for lunch.
We consoled ourselves with a good lunch and some alcoholic beverages and assured each other that the morning was over and fishing this afternoon would be much better with our fishing guide. We arrived at the dock at the appointed hour to meet our fishing guide; nosing into the dock was a sleek 20 foot fishing machine with you know who at the helm. To say the reception was frosty would be putting a good face on it. As it turned out, our intrepid guide was a better fishing guide than a duck-hunting guide and by the end of the afternoon we had almost forgiven him for the morning.
We were fishing for red fish and we got into some seriously good fish. It’s a sad fact that even though we were not taking any fish away with us every legal fish that came on board was promptly knocked on the head. It would appear to be a matter of pride for the guides not to come back to the dock without limits of fish for everyone in the party. In the end we gave the fish away to the people on the dock. After a successful afternoon our feelings towards our guide had softened to the point we invited him to join us for a beer or two at the bar by the dock.
He refused!
Graham Gurr
Published in
Issue 170
Tagged under
Monday, 04 September 2017 11:50
Australian Bittern
NZ Members brave the weather.
The weather was not wonderful, but Robin and Heather List are seasoned birders and the pair set off to Wairio to check on the birds and do a count.
Robin said "The expedition consisted of Heather and me. We have the gear and do wetlands in squalls right cheerfully so there was no grumbling in the ranks, though the waterproof notebook was abandoned in favour of a little recorder, which worked well under wet windy conditions. The sun broke through at times and the whole place was looking grand at wetlands in winter can."
Published in
Issue 170
Tagged under
Monday, 04 September 2017 00:31
Out there for the Long Haul
One of our DUNZ directors featured recently in an issue of the National Farming Review. That person is Dan Steel of Blue Duck Station. The writer was none other than Lou Sanson, Director-General of the Department of Conservation.
Dan was eager to point out that Blue Duck Station is 100 percent effective. Every square metre does its bit for biodiversity in one way or another, be it pasture, native bush, wetland, river bank or the sites housing beehives.
Mr Sanson says DOC cannot achieve all its conservation targets alone and he therefore considers Dan Steele as one of the enthusiasts contributing to DOC’s 2025 targets for pest management and attracting international visitors. As most DU members will know, Dan has his own freehold property along with a family lease that covers 2800 ha. This farmed area carries 5400 breeding ewes, 1000 hoggets, 100 deer, 330 breeding cows and 470 other cattle.
However it is the blue duck (Whio) and kiwi populations on which Dan has focused efforts for the last 10 years. After losing a brood of ducklings he quickly set about organising an efficient pest control programme. Pest control is only part of the answer as flooding streams and rivers mean the Whio nests and eggs can easily be washed away. Dan recovers eggs and sends them to incubate at nest egg facilities. After hatching they go to DOC’s blue duck hardening facility at Turangi, and eventually return to the river. Dan said the Whio are still only holding their own, though kiwi numbers are increasing.
(The above material are excerpts from the original story in the December issue of National Farming Review,
written by Lou Sanson, Director General, DOC).
written by Lou Sanson, Director General, DOC).
Published in
Issue 170
Monday, 04 September 2017 00:19
Eye-catching Signs
Signs of the Times
South Featherston School designed some signs for the Wairarapa Moana Wetlands Project to help raise awareness of the threatened birds breeding around these areas. The signs were put in place and each has an attached map and some photos showing the locations.
Anna Burrows, ranger and operation (Biodiversity) for DoC oversaw and organised the locations, and now it is time to take them down.
“I’ll pull them all back in at the end of February once the birds have finished breeding,” Anna said.
Anna Burrows.
Published in
Issue 170
Tagged under
Monday, 04 September 2017 00:16
Hard Work at Boggy Pond
Steve Playle of the Greater Wellington Regional Council (GWRC) was on the job in early January getting trapping work done around Boggy Pond in the Southern Wairarapa.
“I started back at GW on the 9th and my first job was to get the trapping work done over 10/11 January.
“Predators caught were 5 ferrets, 1 weasel, 8 rats, 21 hedgehogs, 4 mice, 1 magpie, 1 rabbit and 1 thrush. Water levels were still very high in the Wairio Restoration Block and at the southern end there were a couple of big flocks of Pied Stilts in residence. At Boggy Pond the Royal Spoonbills were back in residence where Tony Silbery took his photos of breeding birds last year. I am assuming there may be breeding taking place again this season.
“The total major predators taken since the trapping commenced in July 2013 now stands at:
- 62 cats,
- 140 ferrets,
- 8 stoats,
- 53 weasels,
- 652 hedgehogs and
- 295 rats.
There was a period prior to Christmas where it went quiet on the ferret scene but obviously there has been some movement over the festive break. It is great to see the water levels so good in the Wairio Restoration Block,” said Steve.
Published in
Issue 170
Tagged under
Monday, 04 September 2017 00:11
Photo Competition
Flight will have space for three winners from each of three categories.
So take your camera where ever you go these coming months. We are looking for photos of ducks and other water birds. Or good scenic shots of the wetlands where they live.
Published in
Issue 170
Tagged under
Sunday, 03 September 2017 08:52
AGM 2017
Brackenridge Country Retreat is our place for this year’s Ducks Unlimited Annual General Meeting,
(5&6 Aug, also Friday evening if you arrive on the 4th) annual dinner and the much anticipated auction. DU was there in August 2014 and members found Brackenridge enjoyable and comfortable.
The weekend event includes a catch-up on Friday evening, the annual AGM the next morning, plus morning tea then a bus trip to visit Wairio Wetlands, which has come on leaps and bounds since our last tour there. Put in a pair of gumboots for Wairio. Lunch follows at the Village café in Martinborough. Brackenridge has the atmosphere of early New Zealand station dwellings and with a view of the Haurangi ranges. Brackenridge Conference Manager Leeann O’Neill said they are looking forward to hosting our group. All members should receive the brochure about events at the AGM, and the information. Brackenridge can accommodate 64 guests, so make sure you do not miss out.
Accommodation
• Studios, two-bedroom cottages with two bathrooms and fourbedroom cottages with three bathrooms (includes self-catering continental breakfast provisions with free-range eggs).
• Indoor heated 20m lap pool, and gym complimentary for guests (16 years and over).
• On site day spa offering therapeutic and beauty treatments (bookings essential).
• Some unites are available at The Claremount in Martinborough for overflow.
Register now for another fun DUNZ AGM.
Brackenridge
White Rock Rd Martinborough
This email address is being protected from spambots. You need JavaScript enabled to view it.
www.brackenridge.co.nz
Ph: 063068115
Fax: 063068119
Published in
Issue 171
Tagged under