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Dave supports biodiversity programmes anywhere between Auckland and the Auckland Islands, but specialises in the Chatham Islands and penguins.

Using a band or ring has been vital to the monitoring and conservation of birds for more than 100 years.  Yellow-eyed penguins were first fitted with leg bands as part of a landmark population study by schoolteacher-biologist Lance Richdale in the 1930’s.

flipper-band

A flipper-band on a yellow-eyed penguin

Unfortunately, leg bands proved to be difficult to read and also caused some injuries so, by the late 1950’s, flipper bands became the standard for marking penguins.

The current banding programme for yellow-eyed’s started in the 1970’s and has enabled the monitoring of penguin survival (to a ripe old age of 24 years) and allowed researchers to know the age and history of the individuals at the focus of their research.

Flipper bands are not without problems.  They decrease the underwater efficiency of the bird and, particularly if poorly fitted or maintained, can cause feather wear and injury.  Alternatives to bands have been explored and one under investigation at the moment is the use RFID tags of the same type used in dogs and cats.  While safe and long-lasting, they do have the downside of  requiring electronic readers to find out if a bird is marked and who it is.

Inserting RFID tag

Yellow-eyed Penguin Trust staff inserting a RFID tag into a penguin chick

Whichever method used, it is important to ensure that those applying the tag are doing so correctly in order to minimise the risk to the bird and maximise what we learn as a result.  Penguin chicks get tagged just before they go to sea and I recently took the opportunity to join DOC staff, Yellow-eyed Penguin Trust and Massey University Veterinary students and oversee the tagging of this season’s batch of chicks on the Otago Peninsula.

Measuring head length

Ranger Mel Young showing Wane Begg and Jim Fyfe the best way of measuring head length

Assisted by volunteers willing to crawl through flax, gorse and nettle, we visited several sites, going to nests found earlier in the season, before locating and capturing the chicks.  Bags are used to restrain the birds while they get weighed, measured and tagged before being released back at their nest site.  The weight tells us how good the food supply is (5-6 kg is the normal range) and measuring the head and feet of the chicks gives us an indication of the sex – the males are slightly larger.

Volunteer Monika Fry with penguin chick ready for weighing

Volunteer Monika Fry with penguin chick ready for weighing

Also along for a day was Jeff Corwin of “Animal Planet” fame, filming for the third series of “Ocean Mysteries”.  Jeff, trailed by his camera crew, enthusastically crawled through the shrubbery, helping capture and measure chicks.  Later in the day he assisted researcher Dr Thomas Mattern with the retrieval and deployment of GPS/dive loggers attached to the parents of some of the chicks we tagged as part of a long-term project looking at where the birds feed.

Ranger Mel Young talking penguins with Jeff Corwin

Ranger Mel Young talking penguins with Jeff Corwin

The opportunity to assist with this work, and spend a few days on the beautiful Otago Peninsula in no less than spectacular weather, was very much worth the being stung by nettle, scratched by gorse, bitten, beaten and pooped on by penguins.

Waiting on penguin

Dr Thomas Mattern and Jeff Corwin waiting for a GPS-fitted penguin to return

Postscript

Since my visit some 57 adult yellow-eyed penguins on the Otago Peninsula have died suddenly, possibly due to a marine biotoxin.  Birds found dead on the beach have been identified by their tag, enabling rangers to locate the nest and keep a close eye on their almost-fledged chicks.  Understanding how the penguins encountered the bio-toxin will be helped by the GPS and dive logger data.

penguin foraging tracks

Yellow-eyed penguin foraging tracks. Credit: Dr Thomas Mattern

By Dave Houston

Declining nest numbers

Juvenile yellow-eyed penguins loitering on Sealers Bay beach in 2001

Waaaaay back in 1981 I encountered my first yellow-eyed penguin on Codfish Island or Whenua Hou.  20 years later I was back on Codfish with DOC colleague Dean Nelson and David Blair of the Yellow-eyed Penguin Trust (YEPT) as part of the first ever census of yellow-eyeds on Stewart Island and its outliers.  While the numbers found on Stewart Island were alarmingly low, things on Codfish looked good with 61 breeding pairs and more than 40 juvenile (1-year old) birds seen.

A ‘classic’ yellow-eyed penguin nest under a rata tree

Eight years later Dean and I went back to Codfish with Sandy King of the YEPT to see if the decline in penguin numbers on the Anglem coast of Stewart Island was mirrored there, we took the best cooler with us fulled with goodies.  A week of searching revealed only 46 pairs, down 25% on the previous count.  We also saw no juvenile birds, an indication that poor food year had reduced the survival of the young birds in their first year at sea.  To be sure that this was not just a temporary blip in a bad year, Dean and I again went to Codfish and searched for nests in 2011.  Again, no juvenile birds were seen and nest numbers had dropped further to just 39 pairs.

This year Dean is back on Codfish on his own to see if the trend is continuing.

Finding penguins

Supplejack tangle: There's a penguin in there somewhere.

Supplejack tangle: There’s a penguin in there somewhere

To the uninitiated, counting penguins seems like ‘a walk in the park’.  Instead it can be a dirty, frustrating and physically demanding task.  Yellow-eyed penguins nest in forest, ususally with their backs to a tree or in dense vegetation and up to 500m inland.  Finding them means starting at their landing point and following the often subtle signs of a penguin track, ocassionally dotted with tell-tale penguin poop.  Unlike us somewhat taller humans, penguins have no trouble negotiating the thick vegetation and seem to take delight in detouring through the thickest supplejack patches on the way to their nests, sometimes necessitating a hands and knees approach.  The smell of seabird poop can alert the searcher that a nest is nearby and then close inspection of all likely looking hollows and thickets is required.

Once found, the nest is checked for eggs, the attending bird is checked for a flipper band or transponder and the nest marked by GPS and flagging tape so that the nest can be revisited later in the season to determine breeding success.

What’s going on?

Dean checking a nesting bird for a transponder

Dean checking a nesting bird for a transponder

Yellow-eyed penguins are long-lived (Dean just found a couple of  birds he banded as chicks 20 years ago) and Codfish island is predator-free, so why isn’t it a penguin paradise?  Despite good breeding success in most years, first-year survival of penguins can be very low in years when food resources are low.  It seems that Codfish has experienced several of these poor years in recent times, meaning that few young birds have survived to enter the breeding population.

While adults are safe on their island sanctuary, at sea they are vulnerable to predators (mainly sharks) and by  enganglement with nets set for rig and elephant fish (species most often encountered in your fish-and-chip shop). The extent of this at-sea mortality is not well understood.

And in news just in…

Dean has just emerged from the bush having found 39 nests, no change on last year (read his search dairy here).  While not great news, it does confirm that last year’s low count was not a ‘one off’ low count and that something is really going on here.  The continued absence of  juvenile birds suggests ongoing unfavourable marine conditions.  Hopefully next year’s count will start to show a positive trend.

Yellow-eyed penguins at sea

Yellow-eyed penguins at sea

Antipodean wandering albatross chick atop Hapeka on Pitt Island

By Dave Houston

Remote Ranger

For 5 years Kenny Dix was DOC’s ranger in New Zealand’s most remote community – Pitt Island.  Situated 25km south of Chatham Island, the 6,000 ha Pitt Island is home to around 30 people – and one pair of Antipodean wandering albatross.

Now working on the “big smoke” of Chatham Island, Kenny recently took the opportunity to return to Pitt to band the wandering albatross chick atop Hakepa, one of the islands high points.   This is the sixth Antipodean wandering albatross chick to be raised on Pitt Island and the fouth for the Hapeka pair.  Taking almost a full year to raise, this chick will hopefully fledge in January and commence wandering the Southern Ocean.  It may be up to 10 years before the chick settles down and breeds for the first time.

Northern Antipodes?

As the name suggests, the primary home of the Antipodean wandering albatross are the Antipodes Islands, some 700km to the south.  Having visited the Antipodes myself, I can see why Hakepa’s windswept plateau,  tussock and fern vegetation and magnificent views seem like home to the albatross.

Kenny Dix and Albatross

Kenny with one of the proud albatross parents

Southern neighbours

Another pair of albatross at the Southern end of Pitt produced a chick two years ago, however failed to return this year to breed.  We’re hoping that they might show up next year so than Kenny can keep up his banding skills.

Pitt Island panorama

Pitt Island

By Dave Houston

A presence of biologists?

Blue penguin at Oamaru

Blue penguin at Oamaru

I’m not sure that anyone has come up with a term for a group of penguin biologists (however a group of penguins is called a “waddle”), but whatever it is, one was recently sighted in Oamaru at the biennial Oamaru Penguin Symposium.  Around 60 researchers, conservation managers, and fieldworkers from DOC, Trusts, eco-tourism ventures and the community turned up to hear a variety of papers on the biology and conservation of New Zealand (and occasionally Australian) penguins.

14 years ago I attended the first symposium and it was all about sharing with the Oamaru community what we had learned about the impact of tourism on blue penguins at the nearby Oamaru Blue Penguin Colony.  Today the symposium covers all the penguin species of the New Zealand region and attracts an Australasian audience.

Some good news, some bad

Counting Snares penguins

Dan Palmer counting Snares penguins

Actually, except for the continuing increase in the blue penguin population around Oamaru and the apparent stability of Snares penguin population, the news for other species wasn’t that good.  Yellow-eyed penguins had an OK year in Otago but on Codfish Island (off Stewart Island) a continuing decline has us puzzled.  Out on the remote Antipodes and Bounty Islands things are not great either with significant declines noted in the erect-crested and rockhopper populations.  Fiordland penguins have proved tricky to count, but despite the development of new, more accurate methods, the news isn’t great.

So what’s the problem?

Yellow-eyed penguins on Codfish Island

Yellow-eyed penguin nest on Codfish Island

In most cases we just don’t know.  Changes in food availability, perhaps related to natural or man-made climate variations, are a probably the most significant factor in current population declines, but we understand the how and why poorly.  The impact of fisheries in both bycatch and influencing prey availability is equally poorly understood.  Research in these areas is time consuming, difficult and hard to fund, so progress in understanding it is slow.

Snares penguin with GPS

Snares penguins headed for sea, one fitted with a GPS/dive logger. Photo: Thomas Mattern

In Trusts we trust

A lot of the management of blue and yellow-eyed penguins in the terrestrial environment is undertaken by trusts, community groups and even commercial enterprises.  These groups, along with DOC, have been successful in managing many mainland sites on which penguins nest; protecting habitat, controlling predators, educating the public and carrying out research.  Despite their good work much remains to be done.  More collaboration between community groups, universities, businesses and DOC is required to help understand and resolve the many issues affecting the long-term viability of our penguin populations.  Maybe you’ll join me in Oamaru in 2014 to hear what progress has been made.

Yellow-eyed Penguin Trust planting

Yellow-eyed Penguin Trust staff and volunteers planting penguin habitat. Photo: YEPT

By Juzah Zammit-Ross

A long history of restoration

Mangere Island in the Chatham’s provides an important predator-free refuge to many rare and endemic invertebrates, birds and plants. Restoration first started on the island in the 1970’s with the Wildlife Service planting akeake shelterbelts in Douglas Basin and on the Top Plateau in an effort to expand the habitat available to black robins. Since the early 1990’s tens of thousands of akeake have been planted on the island thanks to the Tuanui and Moffet families and planting contractors.

Mangere plantings 1981

Plantings in Douglas Basin in 1981. Photo: Dave Crouchley

Diversification

As part of the ongoing restoration I led a team of seven people in a week of planting on the island in June.  Although the weather was a bit on the miserable side (gale force winds, very cold and hail most days), we kept warm carrying the heavy bags of plants from the boat landing up to the planting area in the basin.  We managed to plant 1850 plants under the emerging canopy, adding diversity amongst older plantings many of which are self seeding and spreading naturally in the basin.

Mangere and Douglas Basin

Looking over Mangere’s Douglas Basin towards Little Mangere

Local produce

The species planted this trip included Chatham Island nikau, kawakawa, hoho (Pseudopanax chathamica), ngaio, mahoe, ribbonwood and matipo. All the plants were eco-sourced, meaning the seeds were collected locally from Mangere, Pitt and South East Islands and were grown in the DOC nursery at Te One before being transported to Mangere and planted.

Tree planting

Filling in the gaps

But wait, there’s more…

As well as planting, we also cleared tracks, checked rat bait stations, ran rodent tracking tunnels and collected seed for future plantings. We also had the opportunity to visit Robin Bush to view the black robins and walk up to the summit  to enjoy the spectacular views of Mangere, Little Mangere and Pitt Island. Next year will be the last year of akeake planting on the island however diversification plantings will carry on for the next ten years as part of the long-term ecological restoration of Mangere Island.

Mangere planting team

Mangere Island winter planting team 2012: Pete Lusk, Nadia Thomas, Ryan Jones, Juzah Zammit-Ross, Mike Van Velzen, Colin Bishop and Denny Prendeville

 

By Dave Houston

Mid-winter opportunity to work on Chatham petrel burrows

In early July each year a small group of DOC workers head out to Rangatira or South East Island in the Chatham’s to undertake end of season work on the Chatham petrel burrows.  This year we decided to give Chatham Island school children an opportunity to join us and experience the magic of Rangatira.

Rangatira Island

Rangatira or South East Island

We were joined by Year 11 Correspondence School students Harriet Graydon and Mia Foley, both of Pitt Island, along with Chatham Islander Jacob Hill, a Year 12 student at St Bedes College, for the 4-day trip. 

After completing quarantine procedures designed to keep the islands pest-free, we caught an early morning fishing-boat ride from the main island to Pitt, to pick up Mia and Harriet.  After a brief stop and exchange of mail and supplies, we departed for the forty minute trip to Rangatira.

The landing

Landing on Rangatira

Rangatira residents

No jetty means a bow landing on the rock platform and a frantic passing ashore of the buckets containing our food and gear, but the team handled it flawlessly. 

As soon as we were ashore we bumped into our first special species, the shore plover.  Once abundant around the coasts of New Zealand, this plucky little shorebird was eradicated by rats and survived only on Rangatira.  Fortunately, it has now been returned to several mainland sites.

Chatham Island black robin

Chatham Island black robin

While hauling the buckets up to the hut we bumped into our next special resident – the black robin.  With around 200 birds, Rangatira is the stronghold for the species and over the next few days we got to see quite a few as they jumped out of the forest at us in anticipation of a mealworm handout.

After settling in we fitted everyone out with petrel boards – special footwear designed to prevent us collapsing seabird burrows as we walked around the island.  We then set off on our main task, checking 250 burrows of the endangered Chatham Island petrel

After checking that this years chicks had successfully fledged (and unfortunately a few didn’t), we did a bit of housekeeping and then put a barricade in front of the entrance to stop other seabirds taking up residence while the petrels are away over the winter.

Checking chatham petrel burrow

Mia, Harriet and Jacob checking a Chatham petrel burrow

While wandering around the forest for a few days we got the opportunity to see more island residents – including the Chatham Island species of snipe, parakeets, tui, tomtit, warbler and skink. 

On our first night we hoped to introduce the visitors to the many seabirds and abundant invertebrates that call the island home.  Unfortunately, the great weather and full moon kept all the seabirds at sea so we had to be content listening to blue penguins braying in the forest.

Petrel boards

Fancy footwear: Petrel boards reduce damage to the many seabird
burrows in the forest floor

Reluctant return

All too soon it was time to pack up, lug the gear back to the landing and await the arrival of our ride.  Our skipper Glen King treated us to the scenic route on the way home, travelling around the bottom and up the western side of Pitt Island, taking in views of Mangere and Little Mangere Islands on the way as well as taking us into an impressive sea cave.

Rangatira view

Harriet, Mia and Jacob enjoying the view from the summit of Rangatira.
Pitt Island in background

Mia and Harriet’s  families were waiting on the wharf at Flowerpot when we arrived, glad to see their kids home safe and just a bit jealous of the experience.  Jacob had to endure another hour-long crossing of Pitt Strait before he could head home, but the experience can’t have been to bad as he wants to come back when we open up the petrel burrows again in November.  I think he’ll have some competition, as the girls want to go too.

Trip home

Jacob and Harriet enjoying the trip home along with
Ranger Juzah Zammit-Ross

The recent hatching of a Chatham petrel chick in the Sweetwater Conservation Covenant on Chatham Island is another significant step in the long road to recovery for one of the world’s rarest seabirds.

In decline

Probably once abundant throughout the Chatham Islands, human exploitation, habitat destruction and introduced predators saw the species restricted to Rangatira Island by the time of its discovery in 1892. 

Chatham petrel chick

A Chatham petrel chick tucked up in its down duvet

Until 1961 farming activity on Rangatira resulted in the petrels being confined to small forest patches, where they competed for burrows with the similarly sized broad-billed prion. Nesting at different times of the year, many petrel chicks were ousted from their burrows by returning prions. By 1990 the Chatham petrel population was estimated to be around 1,000 birds and heavily outnumbered by some 600,000 broad-billed prions.

Detering prions

Studies found that while adult Chatham petrel survival was high, less than 50% of pairs were managing to fledge a chick, placing the population in peril. So, finding a way to deter prions from entering Chatham petrel burrows was a priority.

Broad-billed prion.

The competition: a broad-billed prion outside its burrow

Natural burrows converted into ‘state houses’

Natural burrows were converted into wooden ‘state houses’ with plastic pipe entrances, to aid inspection of the contents, and efforts were made to dissuade prions from using them by removing any found within and relocating some distance away. This required frequent nightly inspections of the petrel burrows and numerous DOC staff and volunteers will have memories of the nightly burrow rounds, clumping around the forest with ungainly petrel-boards attached to their footwear to avoid crushing the numerous seabird burrows. It was futile.

Wetsuits work

Lincoln University researchers finally came up with a simple solution – stretching a piece of neoprene wetsuit material over the entrance of the burrow pipe and cutting a slot just large enough for a petrel to squeeze through. It has proved remarkably effective, the petrel ‘homeowner’ tolerates the inconvenience of a tight squeeze, but prospecting prions are deterred by it. This, along with barricades erected while the petrels are away over the winter has increased nest success to around 90%.

Chatham petrel burrow and flap.

A Chatham petrel squeezing through the anti-prion flap into its burrow

New colonies

The relative abundance of Chatham petrel chicks has since allowed for the next phase of recovery, the creation of new colonies on Pitt and Chatham Islands.

200 chicks were translocated to new homes in the predator-proof Elizabeth Ellen Preece Conservation Covenant (aka Caravan Bush) on Pitt Island between 2002 and 2005. Hand-fed until ready to fledge, the chicks remembered Caravan Bush as their new home and some returned after two or three years at sea with the first pair breeding in 2005.

Rangatira and Pitt Islands

Rangatira Island (left) and Caravan Bush (right) on Pitt Island

Return of Chatham petrel to “Sweetwater”

Once the success of the Pitt Island translocation was evident work started on the return of Chatham petrel to “Sweetwater” on Chatham Island in 2008.

Chatham petrel.

Ranger Antje Leseberg checking the band on an adult Chatham petrel

In partnership with the Chatham Island Taiko Trust another 200 Chatham petrel chicks were moved over 4 years to nest boxes within a 4ha predator-proof enclosure built by the Trust. As at Caravan Bush, petrel sounds played over loudspeakers encouraged returning petrels to land at the site.

The first indication of success at Sweetwater was seen last autumn when a pair of petrels were seen in a burrow. After wintering off the South American coast, the pair have returned to Sweetwater and laid an egg in February.

Taiko Trust members were delighted to find a chick present during burrow checks in early March. All going well this chick should fledge in May and spend 2-3 years at sea before returning to Sweetwater. By then it should have more company, as four more burrows show signs of activity, surely signalling the sweet smell of success.