Protecting value: News in Brief
New agents threaten ragwort’s last frontiers
Ragwort has long been one of New Zealand’s most economically damaging weeds, but its last strongholds are being challenged by new insect foes. The ragwort fl ea beetle has greatly reduced ragwort throughout most of New Zealand, but the weed persists in some areas, including the West Coast. It reduces farm productivity, can cause liver damage to cattle and is fatal to horses. In 2002 the annual cost of ragwort control on land in active dairy production alone was estimated at $2.5–4.2 million.
The West Coast Ragwort Control Trust, formed by farmers, dairy industry representatives, regional council and DOC staff , and the New Zealand Landcare Trust, contracted Landcare Research to find a solution.
Researchers discovered high rainfall may suit ragwort but not the flea beetles. The West Coast Ragwort Control Trust therefore applied to ERMA New Zealand to release two new biocontrol agents.
The ragwort plume and crown-boring moths are being successfully used in Australia. Tests show the moths are unlikely to attack anything but ragwort. Landcare Research mass-reared these moths and released them on the West Coast for the first time in autumn 2006. Releases will be made in other areas this spring.
Funding: MAF Sustainable Farming Fund, Coast-based organisations
Bad news for possums, good news for weka
Landcare Research has developed “excluder” devices to keep rats and weka out of cyanide bait intended for possums, while reducing the cost of possum control.
Feratox® cyanide pellets are a cost-effective tool for ground-based possum control, and have low environmental persistence. Bait is commonly presented in bags stapled to tree trunks, at heights easily accessible to possums.
However, weka and rats can also access the bait bags. Use of cyanide pellets is therefore prohibited where weka are present, to avoid unwanted weka mortality. Meanwhile, rat interference can significantly decrease bait availability for possums, which drives up the cost of possum control; usually without the side benefit of killing rats.
To address these problems, Landcare Research developed two lightweight, simple and cheap prototype excluder devices for deploying cyanide pellets. Both are designed to keep out all species except possums, and to be easy for operators to carry and deploy in large numbers without substantially increasing labour costs.
Pen trials and preliminary field assessments have shown the devices to be very successful. Completion of field-testing is expected in 2007. Future plans include end-user testing of current designs, and the inclusion of biodegradable components in the devices.
Funding: FRST, AHB
Pre-feeding good value for money
An investigation into the cost-effectiveness of pre-feeding possums with non-toxic bait before aerial poison baiting has shown it warrants the expense.
The research team analysed historical data and indexed possum numbers before and after control, with and without pre-feeding, in four contemporary possum control operations. They also modelled the time to further treatment to possum control.
The team found higher possum kills were achieved with pre-feeding than without, apparently by getting possums accustomed to the bait. Also, possum population recovery was prolonged by 4–7 years. The research indicates that pre-feeding should be used for all aerial baiting against possums.
Researchers also monitored numbers of native tomtits, a species that is sometimes adversely affected by 1080 poisoning operations. Pre-feeding appeared to have no major adverse effect on the tomtit population.
Funding: AHB
Future looks brighter for Central Otago icons
They’re black and gold, fleet of foot and critically endangered – but new efforts underway will help save two charismatic native skink species from extinction.
Grand skinks and Otago skinks are predicted to die out in less than 10 years without intervention. These large skinks (up to 30 cm long) bear live young and, as keen fruit-eaters, may play an important role as seed dispersers.
Both are brilliantly camouflaged against the lichen-covered rocks they live on, but are ill-protected from habitat destruction and predators, including rats and cats.
DOC commissioned Landcare Research to write the recovery plan for the skinks. Recovery plans are crucial blueprints for conservation strategy and give guidelines for resource allocation.
Landcare Research is a member of the Grand and Otago Skink Recovery Group, which provides technical advice to DOC. The group will finalise the plan in conjunction with interested parties such as conservation boards, concerned individuals and other organisations.
Landcare Research and DOC are partners in the Central Otago Ecological Trust formed to help the skinks. Planning is underway for a skink breeding facility near Alexandra, and for the establishment of New Zealand’s first dryland sanctuary within 4 years.
Funding: DOC
Tiny clay particles pack big power punch
Landcare Research has several exciting projects currently underway using “nanoclays” – “smart” natural or synthetic clays with particles as small as 10-9 m thick (that’s one billionth of a metre). Nanoclays have special surface charge properties, and uses include treating wastewater, recycling nutrients, mitigating greenhouse gas emissions and adding value to primary products.
Projects involve developing applications to help reduce water shrinkage of woollen fabrics and for reducing gas permeability in packaging to make food last longer.
Funding: Technology New Zealand, Canesis Network, New Zealand Trade and Enterprise
Collaborative project scores international orders
Landcare Research and Christchurch technology firm Streat Instruments have produced a device that reduces labour and improves accuracy in soil hydrology tests.
Equi-pF automates the tedious and often error-prone manual procedure for testing soil samples and plotting soil moisture release curves – the fundamental descriptor of soil water movement and storage.
Equi-pF was invented by Landcare Research scientist Dr Jagath Ekanayake and is being manufactured and distributed under license by Streat Instruments. There is overseas interest in Equi-pF with units recently sold to laboratories in China and Scotland.
Dr Ekanayake says that as well as releasing laboratory staff from a repetitive task, Equi-PF produces more accurate results than manual tests.
Funding: FRST, Technology New Zealand www.streatsahead.com
Movies and TV go green
Film production is an emerging industry for New Zealand with the potential for considerable overseas revenue. The biggest drawcard for New Zealand’s screen production industry may well be New Zealand itself, and a new toolkit is helping to protect the unique relationship between the industry and the environment.
Greening the Screen is designed for use by all levels of the industry. Launched in November, it is believed to be the first of its kind in the world, and offers guidelines, examples and solutions for reducing waste and resource consumption.
As a pilot project Greening the Screen was taken up by South Pacific Pictures, producers of Shortland Street and Whale Rider. It also has the support of key screen production organisations including the New Zealand Film Commission and the New Zealand Screen Council, as well as the Waitakere City Council and the Ministry for the Environment.
As is often the case, environmental stewardship is also good business sense. South Pacific Pictures Managing Director John Barnett says, through Greening the Screen and with very little effort, the company has significantly reduced waste and also saved money.
Greening the Screen is a partnership between the Ministry for the Environment, Landcare Research and the Screen Production and Development Association.
Funding: MfE, Waitakere City Council, Landcare Research