Stuff them in a roll or slap them on a piece of white bread; sausages are a Kiwi classic. Stoats and feral cats have a taste for them too. In a recent trial, researchers investigated whether these introduced predators would find and eat sausage bait, and also if native species would also be attracted to … Continue reading Sausages on the menu: trials target feral cats and stoats
Described as “murderous saveloys with legs”, new research reveals weasels cannot be underestimated as a threat to native wildlife. It is suggested we pay closer attention to the recovery of native species rather than simply counting the number of predators killed. The impact of stoats is well documented, but DOC ranger Jamie McAulay and wildlife … Continue reading Bird count not body count: weasel study suggests recovery of native species more important than predator kill count
Part 3 of our series Cat catastrophe: Why are we behind Australia in managing cats? Cats are the eighth-most populous species in the world and are found on every continent except Antarctica. But, as invasive species across many of these continents, their popularity comes at a tremendous cost. Despite Australia’s differences in land size and … Continue reading Cat catastrophe: The final frontier – managing feral cats
Spring has sprung and the stoat mating frenzy has begun. From the moment they open their eyes as babies, female stoats are almost certainly already pregnant. It might be jarring to our human sensitivities but stoat reproduction is undeniably impressive. Clever copulation Each spring, pregnant female stoats find a cosy den to hunker down and … Continue reading It’s business time: stoat mating mania and what you can do about it
Part 2 of our series Cat catastrope: Why are we behind Australia in managing cats? Curfews, leash walking, registration, and desexing. These are just some of the ways Australia is addressing domestic cat management and getting further ahead of Aotearoa New Zealand in protecting their threatened native species. In part two of this three-part series, … Continue reading Cat catastrophe: Managing our feline companions
Feral cats live on every continent except Antarctica – surviving in deserts, forests, farms, and cities. But even though they can live almost anywhere, some habitats are more appealing than others. New research published in the New Zealand Journal of Ecology found that landscape type might play a role in how far feral cats wander. … Continue reading The feral factor – new research into roaming feral cats
Part 1: One massive problem, two different approaches As Kiwis, we pride ourselves on leading the world when it comes to protecting our native species. Our ambitious and ground-breaking Predator Free 2050 goal – and the investment and ingenuity behind it – is unlike anything seen elsewhere on the global stage. Why, then, are we quickly … Continue reading Cat catastrophe: Why are we behind Australia in managing cats?
Trapping using food-based lures of hens’ eggs and rabbit meat, with long-life rabbit is the main stoat control method in New Zealand. But stoats vary in their food preferences and if food is plentiful in their environment, they just may not be that interested. Elaine Murphy of the Department of Pest Management and Conservation at … Continue reading Odour lures offer a new temptation to stoats
New research published in the New Zealand Journal of Zoology shows that mast years are bad news for kea. Native beech trees produce millions of tasty seeds in a mast year, which rodents love. The rodent populations explode, setting in motion a devastating cascade of events. But it’s when the masting stops that taonga species … Continue reading Flying at half-mast: connecting kea decline to mast years
In many wildlife sanctuaries around New Zealand fences make it almost impossible for most introduced predators to get in. But mice can still sneak through – and without those larger predators, their populations can explode. But is this fact something we should be worried about? A five-year research project led by Manaaki Whenua – Landcare … Continue reading When it comes to predator free, do mice matter?
Good for rat population control, but not a stand-alone tool – that’s how two scientists have described the success of self-resetting traps on Goat Island. In a recent study, Auckland University biologists Dr Markus Gronwald and Dr James Russell tested 10 Goodnature A24 self-resetting traps on Goat Island (Te Hāwere-a-Maki). They found that while the … Continue reading Self-resetting traps useful for rat control, not eradication
To survive and succeed in the wild, every meal an introduced predator eats has to be worth the effort and energy it takes to obtain it. Bird eggs and young chicks are an easy, protein-rich food source, especially when birds nest on the ground. So how do you convince riverbed predators that ground nests are … Continue reading ‘Fake news’ foils would be predators
There are a lot of cats in Australia – researchers have calculated that the total number of feral cats in largely natural landscapes averages 2.07 million (varying between 1.4 million in drought and average years to 5.6 million after prolonged and extensive wet periods in inland Australia). Then there are the strays (an estimated 0.72 … Continue reading Feral cats feast on Australian reptiles
Wrybills, the little shore birds with a bend in their beak, are only found in New Zealand. They breed on the South Island’s braided rivers with well-camouflaged eggs and chicks to help protect them from flying predators. But camouflage is no protection against mammal predators who hunt by scent. Does predator control help improve survival … Continue reading Breeding wrybills face multiple challenges
Rat-trapping started early in Aotearoa’s history. The Polynesian ancestors of Māori brought the kiore across the Pacific in their voyaging waka, probably around the 13th Century AD and early Māori developed several types of ingenious rat traps to catch them. Aotea, Horouta and Māmari waka traditions mention that kiore were passengers on their voyages to … Continue reading Rat-trapping has a long history in Aotearoa
A common way to monitor what insects or lizards are around, is to use a live-capture pitfall trap which skinks, geckos and ground-based insects then fall into. With lizards, slices of pear or sometimes petfood are used to attract them to the trap. But lizards and insects might not be the only species to take … Continue reading Predator pitfalls for live-trapped lizards
A recent study by Brandon Breedt and Carolyn King provides the first estimates of the proportion of the Waikato Region occupied by each of the target introduced mammal predator species. The results offer a warning to pest managers that pests are more widespread and harder to remove than is commonly assumed, and that the absence … Continue reading Waikato pest distribution, detectability studied
Hedgehogs were first introduced in New Zealand in the 1870s to make British settlers feel more at home. Now, 150 years later, the impact hedgehogs have on our native species is only just being understood. For a long time, they were seen as innocuous garden inhabitants, but with more research, the picture is becoming clear. … Continue reading 7 surprising facts about hedgehogs
Reinvasion by predators, of previously cleared areas, is one of the many challenges of becoming predator free. We can’t fence huge tracts of wilderness – but we can potentially make use of natural barriers. Possums, for example, may be reluctant to cross rivers. Anecdotal reports that rivers are an obstacle to possum expansion have been … Continue reading River tested as reinvasion obstacle to possums
Researchers Susan Walker, Joshua Kemp, Graeme Elliott, Corey Mosen and John Innes used 264,457 rodent tracking records collected quarterly from 23,709 tracking tunnel stations in forests across the length and breadth of New Zealand over an 18 year period from late 1999 to late 2016 to get a clearer picture of how ship rat and … Continue reading Rats, mice and 264,457 tracking records shed light on rodent dynamics
The kiore is Aotearoa’s first, smallest and sometimes overlooked rat. It was also our first introduced mammal predator, arriving about 750 years ago with seafaring Polynesian explorers. Because of its arrival history, the kiore is considered both a threat to our native taonga and also a taonga itself – an unusual position for any New … Continue reading Study looks at kiore when rival rat species absent
When you remove predators from islands and restore forest habitat, the expectation is that native forest birds will flourish and that the new ‘improved’ conditions may favour native birds over introduced species. But is that what happens? Researchers John Ralph, Carol Ralph and Linda Long looked at how bird populations on the seven islands and … Continue reading Tūī numbers treble in predator control study
In the past there’s been some uncertainty over the effectiveness of large-scale aerial 1080 operations to control mice and little is known about its effect on hedgehogs. Recent trail camera monitoring of mammal predators before and after a control operation in the Blue Mountains, West Otago, suggests the operation not only controlled rats, stoats and … Continue reading Blue Mountains study shows 1080 effective – even for hedgehogs, mice
Feral cats are nocturnal, elusive creatures and can cover a lot of ground. They can range up to 6 kilometres, making monitoring difficult. So how do you go about detecting them? Camera traps are a useful, non-invasive way to determine whether you’ve got feral cats in your reserve. But most monitoring budgets don’t allow a … Continue reading Catching feral cats on camera
When researchers tested a dual baiting regime on ship rats back in 2016-2017, they also made some interesting observations about possum behaviour in their study area. Could dual baiting be adapted to overcome the bait-shy behaviour of possum survivors too? Department of Conservation and Landcare Research scientists, Graham Nugent, Richard Clayton, Bruce Warburton and Tim … Continue reading Dual 1080 bait switch solves bait-shy possum issues
How far might young rats disperse if they find themselves in a place with few other rat competitors? It’s an important question, with implications for deciding what surveillance is needed to detect invasions in predator-free islands, sanctuaries and ultimately, large predator-free mainland areas. But to find out how far rats disperse you need to release … Continue reading Rats on the move – how far do they disperse?
Sanctuary fences keep predators out – but they’ve also become a popular ‘highway’ for ship rats travelling around the sanctuary exterior. Rats have discovered that the rolled steel hood (designed to stop mammals climbing over the fence), also makes a great way to get around, safely out of reach of their own predators like stoats … Continue reading What’s happening up in the hood?
Cautious rats – bait shy and trap shy – are a problem worldwide and researchers at the University of Liverpool, UK have been looking at other ways to attract rats into bait or trap boxes. So far the research has only been carried out on lab rats and still needs to be tested in the … Continue reading Liverpool researchers study rat audio lures
Did you know there were once horses on the Auckland Islands? Possums were deliberately introduced too but didn’t last long. Hardly surprising. It’s a harsh environment and not remotely like their warm Australian homeland. Scientists investigating mammal predators in the Auckland Islands group have switched to studying history recently, looking at the very early records … Continue reading Auckland Islands introductions included horses, possums, chickens
How do you detect the presence of rats and mice if they’re surrounded by a glut of natural food? If it’s a mast year and there’s a carpet of seeds on the forest floor, they just may not be interested in your peanut butter-flavoured chew cards. If there are only a few remaining rats or … Continue reading Detecting rodents during a food glut
Achieving Predator Free 2050 goals will take more than just a scaling-up of eradication efforts according to researchers Duane Peltzer et al from Landcare Research (Lincoln) and the University of Canterbury. They look beyond economic and technological feasibility to identify the key impediments we need to overcome, in a paper recently published in the Journal … Continue reading Identifying impediments to PF goals
The results of the latest Public Perceptions of New Zealand’s Environment have just been released and, as with the previous survey in 2016, the research includes a section produced in collaboration with Predator Free New Zealand Trust and the BioHeritage Challenge, Ngā Koiora Tuku Iko, investigating public perceptions and opinions relating to predator control. “The … Continue reading Latest ‘Public Perceptions’ survey gives insight into predator control views
Now that an increasing number of our wildlife-rich – but uninhabited by humans – offshore islands are becoming predator free, the conservation spotlight is turning to some of New Zealand’s inhabited islands. But predator eradication becomes more complicated when people are living onsite. Its not just about what’s technically possible. It’s also about what people … Continue reading Hauraki Gulf islanders surveyed on pest control attitudes
A survey of 71 islands in southern Fiordland in the summer of 2017, by researchers from Museum of New Zealand Te Papa Tongarewa and the Department of Conservation, found forty breeding colonies of three petrel species spread across 35 of those 71 islands, according to a report just published in Notornis, the scientific journal published … Continue reading Researchers surprised by petrel numbers on ‘refuge’ islands
Tuhoe researchers recently joined other scientists in evaluating naturally occurring toxins in native plants. Could one of those toxins provide a culturally acceptable alternative to existing rodenticides? The results of their study have just been published in the New Zealand Journal of Ecology. Anticoagulant poisons have been used to kill rats and mice for decades, … Continue reading Native plants show potential as future rat toxins
The ruru (morepork) is a predator – but it’s certainly not on the ‘predator-free’ hit list. Those slots are just for introduced mammal predators which haven’t co-evolved with our vulnerable native species. Ruru do prey on other native wildlife however, including endangered species, as a recent study carried out on Tiritiri Matangi Island reveals. Sarah … Continue reading Video camera study reveals rare birds in ruru diet
If you park up at the beach with a feed of fish and chips it can seem like red-billed gulls are common and thriving. But 52 years’ worth of observations and monitoring data from New Zealand’s biggest gull breeding colony on the Kaikoura Peninsula tells a somewhat different story. Mammal predators are part of that … Continue reading Kaikoura red-billed gull study reveals predator impacts over 52 years
Approximately one-third of New Zealand’s islands are now free of all invasive mammals. Could Auckland Island be next? Predator control and eradication operations are often carried out in winter – when predators are hungry and uptake of bait likely to be greater. But when it comes to eradications of sub-Antarctic islands, like Auckland Island, the … Continue reading Would summer eradication of rodents work for Auckland Island?
Dual 1080 operations – would two toxin applications a few weeks apart work better than one? Possibly, if a few other conditions are also met. Currently, aerial 1080 drops are used to control introduced predators, but not expected to totally eliminate them. Aerial 1080 application is used to knock predator numbers right down and give … Continue reading Dual 1080 application could be key to possum and rat eradication
Trappers from the Kepler Challenge Trust helped out by supplying 248 trapped ship rats back in 2009-2010, so that researchers Kay Clapperton, Fraser Maddigan, Warren Chinn and Elaine Murphy could carry out a detailed study of what the Fiordland ship rats had been eating before they died, the population structure of young and old rats … Continue reading Life of plenty for beech forest ship rats
Up until the 1950s, most pest control toxins for vertebrates, including rats, were fast-acting. While a quick death for pests is a good thing humane-wise, the issue was, rats didn’t necessarily die. They’d try a little toxin, quickly feel the effects and sensibly refuse to have anything more to do with it, before they’d consumed … Continue reading New toxin combination tested for rats and possums
When scientists studying the dynamics of a Norway rat colony in New York had some wild cats moved in on the experiment, they took the opportunity to see how the presence of cats and their behaviour influenced the presence and behaviour of the rats. Did rats move out when the cats moved in – or … Continue reading Can feral cats limit rats?
‘Giant rats’ in our cities have hit the media headlines in recent weeks and, while ‘rats as big as cats’ are unlikely to be stalking the suburbs, there do seem to be some large and well-fed rats lurking in urban areas. What’s more – the rats that your cat brings home may not be the … Continue reading Cats vs Rats (and the big ones that get away)
Thermal squeeze: it’s what happens when temperatures rise, predators spread out to higher altitudes and their vulnerable prey species are squeezed into less-than-ideal pocket habitats at the outside edges of their range. Like most predicted consequences of climate change, it’s not good news. So will it happen to New Zealand species? If so, what species … Continue reading Thermal squeeze could put pressure on native wildlife
A 22-year study in Tongariro Forest has followed 142 radio-tagged North Island brown kiwi through 4 landscape-scale aerial 1080 operations, covering an area of 20,000 hectares. Not only did all 142 kiwi survive the 1080 drops, but the long-term study reveals a swag of other interesting information on kiwi chick survival and fantail nesting success … Continue reading Long-range study follows kiwi for 22 years
Peanut butter is the standard rat attractant – and apparently, they’re pretty keen on chocolate and Nutella too. But researchers at Victoria University of Wellington’s ‘Centre for Biodiversity and Restoration Ecology’ have come up with some chemical compounds that wild rats seem to rate even better than peanut butter. The quest for an irresistible rat … Continue reading New clues in the search for synthetic lures
Recently there have been several research projects looking at predators in the alpine environments of the South Island. It’s a completely different ecosystem to the much-studied lowland forest systems and there’s still a lot to be learnt about the key predator threats to our alpine species and how best to address those threats. In his … Continue reading Latest research from Otago University and DOC investigates rock wren and 1080
To achieve a predator free New Zealand by 2050 – or by any date – the majority of New Zealand will need to back that goal. Young people in particular need to want it to happen and be engaged in making it happen. After all, it’s their future, 30 years from now, that we’re talking … Continue reading PF2050 – do young people support the goal?
Rats are bad news for nesting birds – but quantifying exactly how rat density relates to nesting success of our smallest and rarest birds is difficult for a number of reasons. They’re rare – so there’s not a lot of them to study; they are likely to live in remote locations making observation difficult and … Continue reading Nesting fantails balance predators and weather risks
Back in 2017, PFNZ Trust talked to Otago Zoology student Jamie McAulay about his Masters research on the diet of stoats. Well the Masters is done and dusted and Jamie’s thesis is now available online through the University’s ‘OUR Archive’ site. So what has Jamie found out? The research project looked specifically at the diet … Continue reading Jamie’s thesis reveals diet preferences of alpine stoats
Monitoring is an essential part of measuring the success of a predator control programme, but monitoring methods used in forests may not be directly applicable to wetlands. Tracking tunnels may not work, for example, where water levels fluctuate significantly. It was an issue that faced Department of Conservation researchers Craig Gillies and Matthew Brady at … Continue reading Monitoring methods trialled in Whangamarino wetland
Insects get eaten too. Scientists have reported that invertebrates have been found in 10-30% of cat guts and scats in the Mackenzie Basin, suggesting high country invertebrates, including some rare endemic grasshoppers, could be vulnerable to introduced mammal predators. Christchurch-based researchers, Jennifer Schori, Richard Maloney, Tammy Steeves and Tara Murray investigate whether reducing mammal predators … Continue reading Insects get eaten too – so does predator control help grasshoppers?
New Zealand researchers have been taking a closer look at the family histories of Man’s long-time travelling companion – the rat. Genealogy meets gene analysis in this study, carried out by Auckland University researchers James Russell, Judith Robins and Rachel Fewster and published this month in the international journal Frontiers in Ecology and Evolution. Kiore … Continue reading Rat genetics tracks invasion back through time
Many of NZ’s introduced mammal predators – including house mice – are good at climbing trees. To understand the impact they have on tree-nesting birds and other tree-living wildlife, we need to learn more about how predators use vegetation compared with the ground. Mice aren’t commonly found in trees, for example, but that changes in … Continue reading Tree-climbing habits of predators studied
Not only do kea nest on the ground, but it takes about 4 months from egg-laying until kea chicks fledge. Four months is a long time to be sitting on the ground facing off the local stoats. Kea eggs, chicks and even adult incubating females are very vulnerable to predation. Aerial application of 1080 can … Continue reading Kea and 1080 – nesting success demonstrated
Researchers from the University of Otago and Department of Conservation have been investigating how to improve the plight of our endangered black-fronted terns in research recently published in the New Zealand Journal of Ecology. Traps, bait stations and a Komatsu bulldozer can all help make riverbed nest-sites safer. But one key predator was still undeterred … Continue reading Clearing river islands may help nesting terns
New Zealand’s regional councils have just released a ‘think piece’ on the future of biodiversity management in New Zealand. “Our native flora and fauna is a taonga that does much to define us as a nation. It’s also under threat, and we are losing ground in many cases. This timely thinkpiece suggests how we could … Continue reading Regional Councils tackle biodiversity challenge
Predator control for conservation purposes tends to focus on reserves, sanctuaries and remnants of native habitat rather than open pastures. When researchers publish articles on pastural predator control, they’re generally focused on possums and TB eradication. But landscape scale predator control on multi-tenure farmland is increasingly playing a part in Predator Free 2050 goals and … Continue reading Hawke’s Bay study shows predator control contributes to farmland biodiversity
You don’t hear so much about weasels. Their New Zealand distribution is patchy and their bigger mustelid relatives tend to dominate the mammal predator stories. But when there was a mast year in 2014, weasels as well as stoats turned up in the beech forests of Nelson’s Maruia Valley to feast on the bonanza of … Continue reading Weasels studied during Maruia masting event
It’s not quite a sugar-coated pill, but the principle is similar – a nice flavoured coating that not only encourages rodents to take the bait, but also protects the toxic cereal bait within from deteriorating over time and going mouldy. Norway rats, in particular, have been found to avoid mouldy bait. Research recently published in … Continue reading Researchers study new ways to stop bait going mouldy
Canterbury’s Quail Island Ecological Restoration Trust has been working with Department of Conservation staff and researchers from Lincoln and other universities to eradicate introduced mammals from the island and document their processes, successes and learning outcomes in an article recently published in the New Zealand Journal of Zoology. “Ōtamahua/Quail Island is an 85 ha Recreation … Continue reading Lessons learned in combating mice on Quail Island
House mice are the smallest mammal predators to have been introduced to Aotearoa/New Zealand since humans first arrived here around 1280AD. The mice arrived on European ships by the 1820s and nowadays they are present in most habitats throughout the country. Worldwide they are among the world’s most prevalent invasive mammals due to their rapid … Continue reading Mice numbers in the absence of mammal predators
D-Block bait and DITRAC All-Weather BLOX are two commonly used, long-life rodent baits with the same active ingredient, the anticoagulant Diphacinone. Rats and mice need to consume bait over several days to get a lethal dose, so it’s important to keep them coming back for more. Although the toxin is the same, the two bait … Continue reading Bait consumption study shows what appeals to rats
Peanut butter has long been used as a bait for rat traps. Possums have a fondness for the scent of cinnamon. But are they the all-time favourite foods of rats and possums? Researchers at Victoria University of Wellington used chew cards to check out what really tickles the tastebuds of two of our more common … Continue reading Better baits and better trapping
With the benefit of hindsight, its easy to condemn those who released rabbits in New Zealand and even more so, those who then released ferrets and stoats to ‘remedy’ the earlier error. What were they thinking? Did they really have no other control options open to them? Were they completely unaware of what the consequences … Continue reading Ferrets and Rabbits – and what history can teach us
We know a lot about the impacts of introduced mammal predators in wild environments and about how to control their numbers in forests and remove them entirely from uninhabited islands. What we don’t know so much about, is the lives and impacts those predators in places where people also live. How can introduced predators best … Continue reading Managing predators where people live too
Statistics are a whole lot more than just a bunch of numbers. They can tell a story. They can paint a picture – and sometimes that picture just isn’t pretty. Take for instance, some of the statistics revealed in ‘Our Land 2018’, a report jointly prepared by the Ministry for the Environment and Stats NZ. … Continue reading ‘Our Land’ statistics paint a stark picture
In research just published in international ornithology journal Ibis, Department of Conservation scientist Kerry Anne Weston, Colin O’Donnell, Paul van Dam-Bates and Joanne Monks investigated the impact of introduced mammalian predators in our little-studied alpine region. Their study revealed that stoats and house mice are the 2 introduced predators having the most impact on New … Continue reading Stoats and mice top rockwren predator list
Cats and dogs are both predators of rats – but to what extent is the presence of cats and/or dogs a deterrent to rodents? How do you even measure how ‘nervous’ a rat feels? Scientists in far-off Swaziland used some interesting techniques to determine how uneasy rats felt in the presence of their natural predators. … Continue reading Investigating a rat’s ‘landscape of fear’
Not every species can be saved by moving it to a predator free island. It has helped the black robin – but it won’t help the black-fronted tern. Islands simply don’t have the habitat that the terns need to breed. Black-fronted terns have a small, declining population and are classified as globally endangered. Predation is … Continue reading No sanctuary option for terns
In New Zealand we tend to focus on the harm rats do to our wildlife and ecosystems. But there’s another side to rats that’s even closer to home – their ability to carry diseases and parasites to people. From pig farms in Canada to the slums of Brazil, recent international research has been looking at … Continue reading Rats and human disease links
Tracking tunnels, chew cards and WaxTags© are commonly used to detect predator presence and monitor abundance, but in recent years there’s been a new tool in the conservation kit – the remote camera. Evaluations of its use are showing that it is a tool with a lot of promise and some significant advantages over traditional … Continue reading Detecting predators in the city – what works best?
How much trapping does it take to make a difference? Sometimes even a small difference can make all the difference to a species that is at a borderline point for sustaining its population. In a recent edition of the New Zealand Ornithological Society’s journal Notornis, DOC scientists Jane Tansell, Hannah Edmonds and Hugh Robertson reported … Continue reading Takahe protection benefits the neighbours
When possums live in an urban landscape, their fondness for fruit, flowers and foliage quickly makes then unpopular with gardeners. They can be noisy on the roof at night too. But the impact they’re having on local birdlife may not be quite so obvious. Well fed on apples and roses, urban possums may or may … Continue reading Urban possums – it’s not just about the roses
Anticoagulant poisons are commonly used to kill rats in New Zealand and around the world. But at least 18 countries in Europe, America and Asia have reported growing resistance in their rat populations to these poisons. Are our rats growing bait-resistant too? Phil Cowan et al from Landcare Research investigated. “Rats, except kiore, are currently … Continue reading Rat bait resistance – should we be worried?
It could have been so much worse… red foxes, Patagonian foxes, mongooses (or should that be mongeese?) – even badgers were proposed as a solution to New Zealand’s rampant rabbit problem back in the late 1800s. One entrepreneur actually thought burrowing owls might sort the rabbits out. Prof Carolyn King from Waikato University uncovered some … Continue reading Narrow escape makes horror reading
Norway rats (Rattus norvegicus) and black rats (also known as ship rats), (Rattus rattus), are among the most prolific and widespread urban pest species in the world. But what do we know about their secret city lives? After all – the more we know, the better we can understand what we’re up against. Just because … Continue reading Secret life of urban rats revealed
When stoats were recently captured on video raiding the spring nests of rock wren, yet tracking tunnels failed to detect their presence, scientists became concerned about the effectiveness of tracking tunnels as a monitoring method in alpine regions. Was there a better way to detect stoats? How did other monitoring techniques compare with tracking tunnels … Continue reading Capturing the cryptic – finding better ways to detect stoats
Stoats tend to vie with rats for the position of Conservation Public Enemy No. 1 – but what do we know about the stoat’s smaller relative, the weasel? Do we underestimate their impact on native wildlife? Kathryn Strang, Isabel Castro, Greg Blunden and Lara Shepherd examined the stomach contents of 16 weasels caught between 2011 … Continue reading Not just mouse-munchers – the diet of weasels revealed
Rats and mice aren’t just our problem. They’re some of the most widespread and damaging invasive alien species on islands globally. A team of scientists lead by Karl J. Campbell from Island Conservation and including New Zealand-based scientists Al Glen and Charles Eason, have carried out an indepth review of what’s just over the horizon … Continue reading What next for rats and mice?
Stoats are emerging as a key threat to our alpine wildlife as scientists learn more about predator/prey relationships in this less-studied habitat. Remote alpine zones are home to unique skinks and geckos, some of which have only recently been discovered, along with insects such as alpine weta which can survive being frozen and the tiny … Continue reading Alpine stoats caught on camera raiding rock wren nests
Rats are fastidious groomers. So how does an animal that grooms frequently react to the prospect of running through viscous tracking ink? Are rats reluctant to get their feet dirty – and if so, what are the implications for tracking tunnel monitoring? Prof. Carolyn King and fellow researchers at the School of Science, University of Waikato … Continue reading Do rats mind inky feet?
The A24 self-resetting trap has been around for a year or two now, but development of the product and testing of its capabilities continues, along with evaluations of how best to utilise the traps in ‘real world’ predator eradications. Darren Peters from DOC, along with the team from Goodnature have recently been putting A24s to … Continue reading A24 vs Stoats – island experiment deemed a success
Cats, cat management and the impact of cats on conservation – it seems that everyone in New Zealand has an opinion and a significant proportion of us own at least one companion cat – but what is actually known about the multiple roles of urban cats in New Zealand? It is becoming an increasingly important … Continue reading City cats – what don’t we know and how can we find out?
It has been estimated that between 25,000 and 45,000 people belong to community-based environmental groups in New Zealand. That’s a lot of volunteer work and, as the estimate was made in 2011, numbers since then are likely to have grown. There’s also a pretty wide range of uncertainty in those estimated numbers – 25,000 to … Continue reading Survey investigates huge volunteer contribution
When there’s a mouse in your pantry you notice – but in the wider environment they’re common and inconspicuous. It’s difficult to know what impact mice have in a forest or wetland environment because mice are overshadowed by – and food for – their bigger predator rivals, including rats, stoats and feral cats. So should … Continue reading Mice – should we be worried?
Ship rats are known to be good and climbing trees – but what are they like at climbing mountains? If our climate gets warmer, might rats go to new heights in the search for new territory and food? Scientists Jennifer Christie and Graeme Elliott from DOC’s Christchurch office, along with Peter Wilson and Rowley Taylor … Continue reading Rats, elevation and implications of climate change
Why did they do it? What possessed New Zealand’s government of the day, its citizens and acclimatisation societies to introduce rabbits and then stoats? It’s easy to judge in hindsight. But perhaps we should do more than judge. A better understanding of what they were thinking at the time might help stop us making similar … Continue reading Liberation of stoats and weasels – a look back in time
When scientists Patrick Garvey (University of Auckland), Alistair Glen and Roger Pech (Landcare Research, Lincoln) tested the response of 18 wild-caught stoats to the scents of bigger, dominant predators, the response of the stoats was the opposite of what they expected. The researchers used towels from the bedding of ferrets and cats (familiar top-order predators) … Continue reading Predator scent may be key to developing long-life lures
Rats are a uniquely serious problem on islands such as New Zealand where there has been a rodent-free evolution of our wildlife and plantlife, but scientists around the world are also looking for better ways to control rats because of their disease-carrying and food-spoilage attributes. Black (ship) rats with their tree-climbing abilities are New Zealand’s … Continue reading Canadian researchers come up with innovative rat-luring techniques
Rats are the introduced predator that homeowners are most likely to combat, according to the results just out from the 2016 ‘Public Perceptions of New Zealand’s Environment’ survey, with almost all respondents who had rats present, reporting that they attempted to control the rats near their home. Poison was the most frequently reported method of … Continue reading Survey reveals public predator control efforts
‘Raptors vs aliens’ – it sounds like the latest Hollywood blockbuster, but it’s actually the title of a paper published in the NZ Journal of Zoology at the end of last year. Written by NZ Landcare Research scientists A.S. Glen and R.P. Pech, along with two Australian authors, the research investigates the complex relationship between … Continue reading Raptors vs aliens – might it work?
We can do island eradications. We’re the world’s best at it. Mainland, regional-scale predator control is one of the next big predator-free challenges and a key part of that challenge is getting every landholder behind the project. What happens if some landholders don’t want to be involved? Will their inaction jeopardise the project? Just how … Continue reading Landholders and landscape scale predator control
What do we know about the effects of introduced mammalian predators in the alpine environment? The short answer is probably ‘not much’. DOC scientists Colin O’Donnell, Kerry Weston and Joanne Monks review the little that we do know in the latest volume of the NZ Journal of Ecology. They identify important gaps in our knowledge and … Continue reading Alpine predator impacts little understood
While PFNZ Trust focuses on 5 key introduced predator species (possums, rats, ferrets, stoats and weasels), we acknowledge that domestic pets – both cats and dogs – are also introduced predators and are potential killers of native wildlife if allowed to stray. Wandering dogs can and do kill kiwi and penguins when they encounter them. … Continue reading Tracking cats on Rakiura/Stewart Island
Eric Spurr and Nicholas Ledguard from the Ashley-Rakahuri Rivercare Group share the results of their group’s extensive predator control and bird monitoring work from 2000-2015 in a recently published issue of Notornis, the journal of the Ornithological Society of New Zealand. The Ashley River is a braided river in North Canterbury (near Rangiora) where eight … Continue reading Rivercare group shares predator control outcomes
Predator control operations are just that – they control mammal predators but do not completely or permanently remove them. Survivors breed and slowly rebuild the population numbers, aided by invasion of outsiders from neighbouring, uncontrolled areas taking advantage of an opportunity to upgrade to some better real estate: competition is less because the population is … Continue reading When rats come back…
Genetic profiling sounds like something from a crime thriller, but it is a modern scientific technique that can be used to better understand the dispersal behaviour of animals and relationships between various populations. Auckland’s various stoat population were recently the subject of a genetic profiling study which revealed intriguing information about connectivity and migration. Female … Continue reading Genetic profiling reveals source of invaders
A huge effort has gone into controlling possums across New Zealand for a number of years, particularly with respect to TB eradication efforts, but what do we know about the overall biodiversity outcomes? Are we on top of the problem? Has native biodiversity benefited long-term from the war waged against TB or are short-term benefits … Continue reading Measuring biodiversity outcomes
Those with the most passionate and strongly held views tend to have the loudest voices in public forums – but do they represent what most people think? Or do the strident calls of a few distort our perception of public opinion relating to an issue? A paper published in 2014 examines New Zealand attitudes toward … Continue reading Public attitudes to pest control – what does NZ really think?