Kia ora from the Department of Conservation (DOC) in Te Anau. This issue of the Fiordland Coastal Newsletter has updates on a range of activities that have been taking place around the Fiordland coast, including the exciting transfer of mohua back to Resolution Island, efforts to get on top and stay on top of coastal weeds, and the imminent completion of the flood protection work at Milford Sound.
It also features information on how the latest DNA profiling techniques are helping inform management of our island eradication programmes, an update on freshwater pests, and a request for sightings of the basking shark, the world’s second largest fish species. Finally there is an introduction to DOC’s brand new Fiordland-wide newsletter Behind the Scenes.
In an effort to remain sustainable, this newsletter is available in both hardcopy and email format. If you currently get a hardcopy but would be happy with an email option, please let us know. It all helps reduce the number of printed copies.
Winery toasts success at the birthplace of New Zealand conservation
Peregrine Wines recently toasted the success of their fourth conservation initiative through the Fiordland Conservation Trust and DOC with the transfer of 60 mohua/yellow-head back to Resolution Island, the birthplace of New Zealand conservation. The October transfer marks a momentous step in conservation being the first time that native wildlife has been returned to the birthplace of New Zealand conservation.
Mohua transfer onto Resolution Island
Resolution Island was declared New Zealand’s first Nature Reserve in 1891 and in the years following caretaker Richard Henry moved hundreds of kiwi and kakapo to the safety of the island, away from the stoats and rats that were devastating the mainland’s wildlife. But with the invasion of stoats to Resolution Island in the early 1900s, Richard Henry abandoned his conservation dreams.
An ambitious trapping project undertaken by DOC over the past three years is helping to restore Resolution Island (20,860 ha) to its former stoat-free status. With a breeding population of stoats no longer present, it is now safe to return endangered or threatened species, such as mohua, to Fiordland’s largest island sanctuary. Due to the size of Resolution Island, it will be able to sustain a mohua population of thousands, making it the largest protected site for mohua in New Zealand.
The mohua were transferred from the Landsborough Valley, near Haast, where numbers have been recovering well since stoat, possum and rat control was established in the valley in 2000. Once an estimated population of just 14 birds, there are now estimated to be at least a thousand mohua in the valley, so transferring 60 to Resolution Island will not affect the Landsborough population.
Mohua are particularly vulnerable to rats and stoats, especially in years of heavy beech flowering as the seeds provide an abundance of food for rats and stoats causing them to reach plague proportions. Large flocks of mohua were once seen throughout the beech forests of the South Island but today only a few remain in small pockets of mainland, or on predator-free islands. Transferring mohua back to Fiordland’s largest island sanctuary will help to secure the future of the species.
The team from ‘Close Up’ who filmed on Resolution Island 3 years ago, were back to film this first transfer of birds.
For more information on the mohua transfer please contact Department of Conservation - Jo Whitehead +64 3 249 0200 or email: firstname.lastname@example.org.
For more information on Peregrine Wines and the Fiordland Conservation Trust contact Fiordland Conservation Trust Manager Rachel Cockburn on 0274 952 954.
Basking shark sightings urgently sought
The basking shark (Cetorhinus maximus) is the second largest fish in the world, and part of a group of large to giant filter feeding elasmobranches that includes the whale shark, manta and devil rays.
A basking sharkAll of the species in this group recorded in New Zealand waters are fully protected under the Wildlife Act 1953. The average size of basking sharks encountered around New Zealand are about six metres in length. However there have been reliable reports of individuals up to nine metres long and some unconfirmed sightings of sharks up to 12 metres. New Zealand appears to be the centre of the species’ distribution in the Southern Hemisphere, with only one confirmed record from Australia in the last 30 years, and a handful of records from Chile.
Hot spots for basking shark sightings within New Zealand include Kaikoura, north and south Canterbury, Stewart Island, the Southern Plateau and West Coast. Aerial surveys conducted around Banks Peninsula by DOC and Dr Demian Chapman from Stony Brook University, New York, for the last two summers have failed to find any basking sharks. The department would therefore like to hear of basking shark sightings anywhere in New Zealand over the last 10 to 20 years in order to increase knowledge of areas used by this species and to aid research on its movements and behaviour. Information such as date, location and number of sharks seen can be reported to DOC by email (email@example.com) or to DOC’s Southland Conservancy Office, + 64 3 211 2400.
Fiordland coastal weed surveillance and control
Once a year a small team of DOC rangers spend a week exploring as much of the Fiordland coast as possible looking for weeds and, of course, killing any they find. The inner fiords are surveyed using the DOC vessel Southern Winds. Stretches of the outer coast, where landing in a dinghy is not possible, are surveyed by helicopter. The two most common weed species found along the Fiordland coast are gorse and marram. Coastal weed surveillance is normally conducted in early spring as this is the best time to spot flowering gorse plants.
DOC Ranger Richard Ewans searches for marram at Spit IslandSurveillance involves returning to known sites from previous years and spraying any seedlings found, as well as searching for new weed infestations at sites favourable for gorse or marram establishment. Coastal weed species tend to arrive in Fiordland from the north, after seed or plants have travelled down the Tasman from New Zealand’s West Coast. If seeds or plants get washed up on a site favourable to them then a new weed infestation can develop. The most likely spots for new infestations are beaches that accumulate a lot of driftwood and other debris. These tend to be the spots that the DOC rangers focus on searching.
Since weeds repeatedly invade the Fiordland Coast, the process of weed surveillance and control is ongoing. So long as gorse plants exist further up the West Coast, gorse seed will continue to wash up on Fiordland beaches. Thankfully, based on the weed survey conducted at the beginning of October, it looks like efforts to control weeds in the Fiords and on the outer coast are proving very successful. Only very low numbers of seedlings have been found at old sites and a small handful of new infestations discovered. A number of sites where weeds had been widespread in past years appear to have been successfully eradicated with no seedlings found in 2011.
While these results are promising it is always possible that some new weed infestations were missed during the survey, as it is not physically possible for DOC rangers to search every metre of Fiordland’s immensely long coastline. For this reason DOC would like to encourage fishermen, pilots, tourism operators and recreational users to please report any weed sightings, preferably with GPS co-ordinates, to the DOC Te Anau Area Office.
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Milford Sound Village Flood Protection
The Cleddau River Flood Protection Project is nearing completion. The project is set to be delivered 'on time' and 'on budget' thanks to the hard work of all involved. The project construction contractor Downer EDI have successfully completed the work without any significant delays or interruptions.
The project’s principal objectives have been to protect visitors and residents, road access and infrastructure at Milford Sound by providing protection from a 1 in 100 year flood. The project consisted of three major elements: constructing and upgrading flood defences to the Cleddau River; moving existing structures from the Cleddau staff accommodation area and then raising ground levels to establish a new platform above a 1 in 100 year flood risk; and finally reinstating infrastructure and relocating buildings onto the new platform.
All of the work was timed to minimise disruption and was carefully planned during 3 years of intensive investigations and consultations. The success of the project was heavily reliant on the commitment, support and assistance of the local Milford community and businesses, especially during the four month period when staff were relocated to temporary accommodation.
By the time of completion in November this year, the work undertaken will have helped to maintain road access into Milford Sound and provided an elevated and protected accommodation site for staff living in Milford.
Please contact Abby Dobell firstname.lastname@example.org at Te Anau Area Office + 64 33 249 0200 if you would like any further information on this project.
Stopping the spread of freshwater pests
Didymo monitoring at a number of rivers in Fiordland National Park, including some that drain into fiords, indicates that most of Fiordland’s rivers remain didymo free. These results strongly suggest that the “Check, Clean, Dry” campaign, led by MAF Biosecurity New Zealand, has been effective in educating users of waterways about the importance of freshwater hygiene and getting into the habit of checking that all equipment is either bone-dry or thoroughly cleaned between catchments.
Didymo debris on bankThe rivers draining western Fiordland are a particularly high priority for two important reasons. Firstly, they are the most intact river ecosystems left in New Zealand, being amongst the only rivers that remain practically unmodified along their entire length, from their source above tree-line right down to where they flow into the sea. Secondly, because they receive relatively few human visitors, they should be among the easiest to keep free of introduced pests such as didymo.
Regular monitoring of the Clinton and Arthur Rivers on the Milford Track has shown that these rivers are still didymo free, despite receiving around 15,000 trampers per year, all of whom begin their walk immediately after crossing didymo-affected Lake Te Anau. This result is largely thanks to the efforts of Real Journeys, Ultimate Hikes and individual trampers ensuring that all footwear is cleaned before starting the track. If the Clinton river can be kept free of aquatic pests with this many people using the valley, and with didymo present right at its very outlet, then the rivers draining into coastal Fiordland, many of which receive only a handful of visitors each year, can surely be kept in their pristine state for many years to come.
It is important to remember that it only takes one person to introduce didymo into a new catchment and once present in a waterway there is no known way of getting rid of it. For this reason it is critically important that all users of Fiordland’s rivers remember to always check their gear and, unless it has been bone-dry for at least 48 hours, clean it thoroughly. The cheapest and easiest cleaning method is to soak until saturated in a solution of 5% dishwashing liquid and 95% water (either fresh or salt). Saltwater will kill didymo on its own but requires soaking for at least 4 hours. Because of the diluted freshwater surface layer in Fiordland this is not recommended as a cleaning method.
It only takes a moment to clean equipment such as boots, gaiters and fishing gear. Hopefully everyone fortunate enough to work and play in coastal Fiordland will remember that they are in one of the most special places left on the planet and continue to do their bit to help keep it that way.
If you would like more information on didymo or didymo cleaning methods, or think you might have seen didymo in any of the rivers draining into coastal Fiordland, please contact Sanjay Thakur at DOC Te Anau +64 3 249 0200.
How DNA is unravelling the truth about invaders on islands
Genetic analysis of DNA from deer and stoats taken during the Secretary and Resolution Island restoration programmes is providing some valuable information for managers. DNA research is helping DOC to understand how many, when, and what animals are swimming out to these islands. In combination with sex and age data (assessed using the teeth of trapped or shot animals) genetic information about relatedness and where an animal has come from will help managers to further refine the programmes on these islands.
Stoat caught in trapStoat DNA on Secretary and Resolution Island is being studied by University of Auckland PhD student, Andrew Veale. Preliminary results indicate that up to 3 individual stoats are swimming to Secretary Island in normal years and up to 11 following rodent-plague years on the mainland. A couple of individual stoats breeding on Secretary Island in the past two summers have also contributed to a higher number of captures from that period than in previous years (25 and 21 individuals in 2010 and 2011 respectively).
While these numbers might sound “big” the summer population of stoats on Secretary Island probably peaked at around 500 individuals back in 2005 prior to the start of the trapping programme. One female stoat can also have a litter of up to 10 young so it would only take 2-3 litters to produce a population of 20-30 individuals. On Resolution Island, which is three times the size of Secretary Island and closer to the mainland, there appears to have been little or no immigration and no breeding, with only 4 stoats caught last summer.
Andrew’s research has shown that older stoats on the islands are generally very hard to catch while the trapping programme is readily catching animals up to 12 months old. Work is underway to investigate methods for targeting older trap-shy animals and reducing levels of stoat reinvasion. Fortunately, the stoats swimming to Secretary Island have been identified as young animals and are being caught in the summer-autumn period after arrival.
Analysis of DNA from deer shot on Secretary and Resolution Islands, as well as nearby mainland populations, have shown the opposite pattern between the islands. The Secretary Island deer population appears to have started from very few individuals and the re-invasion rate is very low. Currently there are probably fewer than 10 deer remaining and DOC hopes to eradicate the population within the next 3-5 years. Preliminary results for the Resolution Island situation show that deer are more frequently swimming to this island. he deer control programme on Resolution Island is into its third year, with close to 800 animals taken off in the first two years.
Marine reserves in Doubtful Sound
There are currently three marine reserves in the Doubtful Sound complex, Te Awaatu Channel (The Gut), Kutu Parera (Gaer Arm) and Taipari Roa (Elizabeth Island).
Up until recently only Te Awaatu Channel (The Gut) Marine Reserve has had any signage to let visitors know where it’s boundaries are but that has now all changed.
Last month members of the Visitor Assets team at DOC erected marine reserve markers on the boundaries of the two newer reserves (Kutu Parera & Taipari Roa) that were gazetted in 2005 as part of the Fiordland (Te Moana o Atawhenua) Marine area.
If you visit Doubtful Sound this summer, now you can clearly see the boundaries of the reserves. For any further information on marine reserves throughout Fiordland please contact the Department of conservation in Te Anau.
Behind the Scenes newsletter
The first edition of Behind the Scenes, the DOC newsletter keeping you up to date with conservation in Fiordland, is now on our website.
Produced quarterly, it will provide you with a round-up of conservation activities and events, covering not only the work of DOC, but also highlighting the conservation achievements in Fiordland of businesses, community organisations and volunteers.
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