EcoLincNZ

Category: wildlife management

  • When grapes lead to war

    Would you steal a loaf of bread to feed your hungry family? Fair enough. What about a couple of grapes to save yourself the misery of wasting nine dollars on sour fruit?

    Grapes, waiting to be sampled.
    © Colin Jensen

    “Try ‘em before I buy ‘em,” is my dad’s usual response to that question, as he pops grapes from three different bags one-by-one into his mouth. A red one here, a green one there, maybe even a dark purple if the season is right. In spite of earnest pleadings from embarrassed children and grocery store placards, there would be no purchase of grapes unless a thorough investigation of both quality and taste had been completed. 

    As weird as it may sound, it turns out my dad is not alone in his grocery store grape grabbing. A quick google search yields numerous articles, blogs, polls and debates on the topic. A more recent article used an extensively rigorous survey of 40 people on Facebook to tackle the question, with results showing that half of respondents advocated for, and actively participated in, grape sampling while shopping. As for the other half? Some seemed to side with this NZ Herald article which refers to grape samplers as both thieves and stealers, while others suggested that this type of behaviour is a “hanging offense”. As a conservation biologist, I am not typically one for philosophical debates, so I’ll leave the ethics of grape sampling and capital punishment up for you to decide. 

    Unfortunately, a jump back into the conservation sphere does not make me immune to grape stealing dramatics. As it turns out, nature, just like the produce aisle of my parent’s local grocery store, is home to its own collection of fruity felons. Among those felons is the European starling. You may know starlings for their incredible vocal range, beautiful coloration, or the massive flocks (or mumurations) they sometimes form (check them out if you haven’t). But to winemakers in New Zealand, starlings may be more well-known for being “vicious” and “wasters of fruit.” Unfortunately the problem that starlings cause in vineyards is nothing new, and in fact, it was this very problem that was the inspiration for research at Lincoln University over 20 years ago. 

    European Starling CC courtesy of Eric Ellingson on Flickr

    Flashback to 1999 – Napster is in its heyday, Brittney Spears’ “Baby One More Time” is on the radio, and, besides a little bit of Y2K hysteria, life is good. Amidst the excitement of a new millennia, researchers Yuki Fukuda, Graham Hickling, and Chris Frampton from Lincoln University were hard at work trying to solve the problem of the grape stealing starlings. To do so, they tested out two devices designed specifically for scaring birds away from agriculture areas – the Peaceful Pyramid and eye-spot balloons. The Peaceful Pyramid, as the name suggests, was meant to be a “peaceful” alternative to other more aggressive bird deterrents like “noisy gas guns”. It featured a rotating pyramid with mirrored sides, which would reflect rays of sunlight towards incoming birds. The goal was to overload the birds vision to the point that they would no longer have the desire to land and feed. The eyespot balloon was a large balloon with yellow and black patterning designed to mimic the eyes of a large predator. 

    Peaceful Pyramid
    © Great Expectations

    Both devices were tested at a vineyard in Dunsandel, and at the University vineyard here in Lincoln. Although both were found to scare starlings away from the grapes initially, within a few days almost all the birds had become habituated to both scarers, and they quickly became ineffective. Ultimately, it was determined that both the eyespot balloon and the Peaceful Pyramid were not practical methods for protecting vineyards. Although these researchers did not find a solution to counteract the stealing starlings, they at least helped re-affirm the idea that anti-bird measures need to be thoroughly tested before they are trusted for protection. 

    In the 24 years since the research at Lincoln was done, there has been no shortage of innovation and testing of bird scaring devices. There has also been some work (here and here) on what birds are doing in the vine-yards. Among the myriad of devices tested, we have seen air cannons, chemical repellents, introduced falcons, large-scale netting, and a few of my favourites, the sci-fi sounding laser scarecrow (unfortunately, this doesn’t look as cool as it sounds), and the RobotFalcon (fortunately, this does look as cool as it sounds). 

    All of these projects have had the same goal: deter birds from pillaging in agricultural settings. Unfortunately, despite each of these ideas producing some level of protection, they all come with limitations. One is too expensive, another is too time and labour intensive, and some only work in good weather. For many, it seems as if finding a fix-all solution to the crop stealing problem is a fruitless endeavour. If it’s not the Peaceful Pyramid, and it’s not the laser scarecrow, then really what more can we do? 

    Well, researchers from the University of Sydney think that they have finally found the answer. (If you have been surprised by any of the bird scaring techniques already described, you may want to sit down for what comes next). Like something out of a Stanley Kubrick film, these researchers have employed techniques that they can only describe as “psychological warfare.” 

    The weapons of war used in this study consist of a stuffed bird attached to a drone (UAV), which is flown through the vineyard whilst playing recorded distress calls of pest birds from a loudspeaker (see image below). The idea is that visual and auditory stimuli on their own are not effective long-term. By tapping into the birds psychology through visual (dead bird) and audio (distress call) cues, they might be able to trigger the birds anti-predator behaviour, and keep them away for good.

    Early results show that crop damage in areas patrolled by this flying fearmongerer are up to four times less than areas which used visual scarers alone. It also appears that this system is just as effective as large-scale netting (currently the most effective way to protect grapes), but is much more cost effective. While these results are preliminary, and further testing is still needed, it seems that hope may be flying (and screaming) in on the horizon. 

    © Zihao Wong – UAV bird scarer as used in: Psychological warfare in vineyard: Using drones and bird psychology to control bird damage to wine grapes

    So there you have it. Starting with a couple of grapes at the grocery store, we end with a weapon of war designed to create fear and confusion. While we may not be any closer to answering the debate about grocery store grape sampling, we at least seem closer to solving the grape stealing starling situation. Will psychological warfare finally be the fix-all solution? Perhaps, but only time (and research) will tell. 

    As for me, I still don’t quite understand what it is about grapes that causes both the starlings and my dad to lose all sense of self-control. Maybe with 24 more years of research, innovation and whatever military tactic comes after psychological warfare, we will finally find that out. I am sure it will be a wild ride. 

    This article was prepared by Master of International Nature Conservation student Colin Jensen as part of the ECOL608 Research Methods in Ecology course.

    Citation: Y. Fukuda , C. M. Frampton & G. J. Hickling (2008) Evaluation of two visual birdscarers, the Peaceful Pyramid® and an eye‐spot balloon, in two vineyards, New Zealand Journal of Zoology, 35:3, 217-224, DOI: 10.1080/03014220809510117

  • A giant pest problem: elephants in the backyard

    New Zealand has a huge agricultural industry. It also has a pest problem. I myself have been out to a friends’ farm and was told to “squash a mouse if you see one”! Which I think we can all empathise with to an extent. When the little b*stards are eating your food, they might as well be infesting your wallet.

    Image CC-BY-SA Diego Delso on Wikimedia Commons: Elephants and humans live in close contact in Africa

    Now, think about scaling that up a couple of levels. You no longer have nuisance, albeit damaging, mice scurrying around your farm shed. Instead you have elephants, in herds of 11+, munching through entire fields and even ripping doors off your grain sheds. Stomping won’t quite suffice here (and may go the other way).

    This is an issue that Abel Mamboleo and his PhD supervisors, Chile Doscher and Adrian Paterson, at Lincoln University investigated in their JOJ wildlife and Biology paper in 2020. Instead of the standard numbers, quantities and figures you may expect in a science paper, here they take a slightly alternative approach to the topic. What do people think is happening in their backyards? After all, fear and perceptions are powerful things.

    To start with a bit of context – who are we talking about when referring to people? This study interacted with people in the region of Bunda, a very densely populated region in Tanzania. Much of its land is a part of the idyllic Serengeti ecosystem, and boasts an internationally renowned tourism hotspot.

    Bunda location within Tanzania – right next to the Serengeti: Image CC-BY-SA Macabe 5387 on Wikimedia commons

    These people rely heavily on farming. In fact, 80% of annual income in Bunda comes from this industry. You can imagine how devastating it is to have these creatures, as amazing and majestic as elephants may be, decimate their fields of crops.

    Elephants eating crops is not a new story. In fact, there are even somewhat humorous accounts of elephants eating rotten fruit in orchards and getting themselves rather drunk in the process. Thieving behaviour may even be tolerated – these giants are big money for tourism. However, in this particular context, such interactions are becoming more and more problematic. In this area, as the human population grows, human-elephant interactions also increase.

    Mamboleo went to this area to ask local people their thoughts about these interactions. Using interviews and questionnaires in local languages to ensure clear messages, they found that 88% of those asked thought these human-elephant interactions were on the increase. Furthermore, 79% of respondents reported these events were most common on farms.

    This in and of itself is not necessarily an issue. Local people had described the elephants as generally ‘docile’ and can even be safely approached to within 50 m. In the past, farmers have sometimes been able to simply scare elephants away themselves using traditional techniques, such as patrolling and fencing. Elephant ‘friendliness’ has even been suggested in other parts of Africa, with some suggesting elephants are going as far as to domesticate themselves. However, now, elephants are beginning to ignore these scaring techniques, some becoming bolder and potentially more dangerous.

    How is this affecting people?

    You can begin to see how conflicts between elephants and humans are likely to grow, with 32% of people thinking that elephants will react to seeing a person by killing them, and guarding crops being a main way for these people to protect their livelihoods. And for another large minority, 42% of those asked, they experienced elephants simply continuing to eat their crops in the presence of humans. Evidently, these people don’t have effective tools to deter elephants and protect their farms.

    Extreme measures: what to do next?

    We can see how people would be having a hard time with their elephant neighbours here. But what about the elephants?

    Elephants are protected in Tanzania. The people of Bunda know this. However, desperate times sometimes call for desperate measures. Therefore, occasionally, when an elephant is raiding crops, people may turn to lethal measures. Whilst few people who were interviewed list this as a response to seeing elephants raiding crops, Mamboleo raises the valid point that this number could be higher. Local people know that there could be consequences of authorities finding that illegal elephant kills had taken place in the Bunda region.

    Elephants & mice – really that different? Image by GlobalP from iStock

    This may seem like a drastic response. However, killing pests such as rats, rabbits and mice that eat crops in NZ doesn’t seem so drastic, does it? Of course, this is a very different situation – elephants are native to this area, and are endangered and protected. But this comparison does make you realise that wanting to kill the problem can be a fairly universal response.

    Mamboleo notes that cheap responses can be turned to in the absence of timely support from conservation authorities…so what can be done about that?

    Well, there are some cool things being done across Africa to help with these conflicts. For example, do you know that elephants are scared of bees? Who’d have thought. Some projects actually exist to build bee hives around fences to keep elephants away, and this seems to work pretty well. It also turns out that elephants don’t like spicy food – so chilli can be used in a similar way.

    Image by Kengee8 on Wikimedia Commons: Example of elephant-bee fence

    More ideas, such as this would, be very useful to help in these situations. Answering questions such as when are elephants most likely to visit the farms may also be helpful for targeted responses, Mamboleo says.

    Knowing how people feel, how they’re responding to the situation, and what they need to do to help them resolve the situation for the best outcomes for people and wildlife is a great first step here. That’s the valuable context needed to now take the next steps and make solutions that will work. Especially when we can’t just stomp on the problem!

    This article was prepared by Master of International Nature Conservation student Sally Sinclair as part of the ECOL608 Research Methods in Ecology course.

  • Kea pine for a new home?

    Kea, our smart alpine parrots, are sometimes a little too clever for their own good. They are a species struggling to maintain large and healthy populations. Part of their problem is that they are very curious and seem to be fascinated by what humans do, and more importantly, often live in human-influenced habitat. This is not such a good trait when it leads them to interact with hazards like lead or toxins, nor is it useful if they find human ‘junk’ food.

    This curiosity is also not helpful when we want to study kea. Many of the approaches that work with other bird species just fail for kea. Instead of going about their business they come and see what you are doing, and that’s not great for understanding key aspects of their life histories.

    Spot the kea at the top of the tree! Image by Adrian Paterson.

    I has some first-hand experience with researching kea about twenty five years ago, when I was a newly minted Lincoln University lecturer. I was helping Kerry-Jayne Wilson to supervise a masters student, Mark Jarratt. Mark was interested in how much lead, and other nasty waste, the kea were finding in the local Arthur’s Pass area, and consuming, in their habitat. For example, lead was present in paints, shotgun pellets and rubbish in the tips and kea were often observed eating it.

    Mark had to catch kea to take blood samples to check for lead contamination. Catching kea can be fairly challenging. They are not easily fooled and they can learn by observing others. Adding to the difficulty was that we had to keep the birds in captivity for an hour or so as part of the procedure. And this was a problem.

    We initially used a cage. We would capture a kea, put it in a holding cage, and then go and try and capture the next one. However, each kea would often figure out how to escape the cage. We would return to find a cage open and our patient free (and not likely to be so easily caught again). So then we took the cage with a kea into a small hut nearby, thinking that if the bird got out of the cage then they would at least be in the hut. Unfortunately, some of the kea managed to figure out how to open the windows in the hut. Moral: don’t work with animals smarter than you are!

    So, when PhD student Jodanne Aitken came to James Ross and me and wanted to do a project on kea, I was a little hesitant. However, Jodanne is nothing if not persistent, passionate and persuasive, and a project on kea was begun.

    Early morning in the plantation. The native forest in the distance was often commuted to and from by kea. Image by Adrian Paterson.

    Jodanne was interested in how kea move about and utilise the landscape. Much of her PhD work is in the Southern Alps around Arthur’s Pass, where she is using transmitters to figure out just how mobile kea can be. Is that kea you see gnawing your car wiper blades from the local valley or could it be from several mountain ranges away? More on that in future EcoLincNZ articles!

    Jodanne’s initial work was in looking at how kea might be using plantations of introduced pine and Douglas fir in the Nelson region. Forestry has become a dominant part of many regional landscapes, often hilly and where native forests once grew (and kea once flew). This is especially the case in the Nelson region. The question that Jodanne wanted to answer was whether these forestry plantations, typically monocultures with a lot of human activity, provide a net gain or loss for kea.

    Jodanne filming kea foraging behaviour. Image by Adrian Paterson.

    Are plantations the equivalent of barren wastes for kea, where there is little food and high densities of mammalian predators (not to mention hazards that humans introduce into an area)? Alternatively, do plantations offer new food resources and places to roost and nest? Of course there could be a range of outcomes from positive to negative.

    Jodanne was able to work in forestry blocks run by Nelson Forestry Limited. Local workers were key to providing Jodanne with almost real-time information on kea presence within blocks that were being actively harvested. One advantage of working in plantations were the forestry roads that gave rapid, if a little hair-raising, access to most of these areas.

    Jodanne was able to capture three kea and mount GPS trackers in fancy backpacks to collect movement data. She also observed kea during the morning and late afternoon-early evening periods for several months, mostly to record their feeding. Jodanne used direct and video observations to observe their foraging. Kea poo was also collected when available to get some physical information about diet.

    The kea with transmitters spread their time between the plantation areas and neighbouring native forest. The majority of time was spent in the pines where they foraged, roosted and nested. Kea were observed eating pine seed, as well as tissue stripped off newly harvested Douglas fir logs. The faecal samples, well the bits that could be identified, contained lots of invertebrates.

    Kea have discovered that they can strip the bark of newly harvested logs, scrape off the cambion tissue, chew this and get something nice out of it. (Maybe a bit like eating sweets?) This may be one of the attractions of being in plantations. Image by Adrian Paterson.

    In short, as summarised in a NZ Journal of Zoology paper, kea seemed to be using the pine plantations in similar ways to more natural areas. Good news! However, one of three kea that carried a GPS recorder was killed by a cat. So, there may be some significant risks for kea spending a lot of their time in these areas. ‘Swings and roundabouts’ as they say.

    Despite this being a relatively small scale study, it does indicate that we could learn a lot more about kea in these highly modified landscapes. Jodanne has taken this training and shifted her sights to a much larger scale project on kea movement in the Southern Alps and southern Westland.

    Kea are one of the smartest bird species on the planet but they still need our help to let them survive the arrival of the smartest mammal species and the changes that we have made. Understanding this clever species is fundamental to helping them. This tricky challenge has been accepted by Jodanne and her research colleagues.

    Article by Adrian Paterson, an Associate Professor in the Department of Pest-management and Conservation at Lincoln University.

  • Kiwi calling: when listening is not enough

    I don’t know about your’s, but my mum gets worried when I don’t respond to her phone calls for a few hours. Once, I can’t remember what I was doing, but I didn’t hear the phone ringing. When I finally checked my phone I saw about 17483 missed calls, oops. I can only wonder what went through her mind when I wasn’t responding: she was probably picturing me skydiving, in an ambulance, or lost in the woods during a hike.

    But what if she’d had a more statistical mindset and thought about why I hadn’t responded? Or even better: what if she’d thought about reasons why she could not detect me?

    Ecologists and conservationists consider something similar when analysing data obtained from searching an area for a certain animal species. An animal could be present at a certain site, but still go undetected. First, they have to consider what ecological reasons might have determined where the species was present or absent (for instance, where is there suitable habitat within the considered area). Second, they have to take into account what factors might have influenced the likelihood of actually observing the species (such as the distance from the observer, or the fact that the surveyor may not be skilled enough to recognise the species). These are defined, respectively, as occupancy (which is the same as saying “presence”) and detection probabilities, and can be estimated by using statistical models.

    Occupancy probability and detection probability are described by two different models and both of them will influence what will be observed during a survey. Taking into account that not all the animals will be observed is very important when attempting to accurately assess a species’ presence, which could otherwise be underestimated.

    A young roroa being released as part of the Operation Nest Egg programme. Image by Jon Sullivan on Flickr.

    Peter Jahn, James Ross, Darryl MacKenzie and Laura Molles, in a study published in 2022, wanted to know how accurate acoustic surveys of roroa-great spotted kiwi (Apteryx maxima) were between 2011-2015. During this time, 18 birds were translocated from the Hawdon Valley, in Arthur’s Pass National Park, to the Nina Valley, in Lake Sumner Forest Park, representing one of the initial efforts of the Operation Nest Egg programme. The researchers also wanted to compare kiwi presence before and after 2015, and between the two areas.

    They gathered data from a survey conducted in 2012-2013 by DOC in both the valleys and then repeated the methodology in 2017-2018. The technique they used was passive acoustic monitoring (PAM). PAM is effective when studying elusive species such as kiwi. Automatic recorders were deployed in the two study areas and left there for up to three weeks, activating just before sunset and switching off shortly after sunrise.

    The team analysed the kiwi calls recorded in each of the valleys. The goal was to find a model that would best describe the obtained data, and use it as a base to estimate occupancy and detection probability. Peter Jahn and colleagues wanted to know which factors were important in detecting the kiwi and looked at the study area (Nina and Hawdon Valleys), year, length of the survey night, breeding/non-breeding season, precipitation, wind speed, night length, varying recorder battery capacity.

    Similarly, my mum could have considered the fact that my phone may have been in silent mode, or had no service, or estimated the actual likelihood of me being in an ambulance. All of these factors could have influenced her imperfect detection of me.

    In both the study areas, the detection probability was found to be higher during the breeding season, to increase with longer survey nights and to be influenced by wind speed, rain accumulation and recorder sensitivity. Also, as expected, kiwi presence in the Nina Valley increased after the translocation, as it did in the Hawdon Valley. Moreover, it was found that the number of sites where kiwi calls were recorded increased in 2017-2018 in both the areas and that, in total, many more calls were detected in the Hawdon Valley than in the Nina Valley.

    The Hawdon Valley in Arthur’s Pass National Park. Image CC-BY-NC by Jon Sullivan on Flickr.

    Wait, the number of sites where calls were recorded and the presence of kiwi increased in the Hawdon Valley after kiwi were removed from there? How is that possible? Yeah, that was one surprising finding of the study. In fact, the researchers were expecting that occupancy would decrease after the birds’ removal, but what they found actually suggests that new pairs re-occupied the territories left inhabited by the translocated individuals.

    This is a promising result, because it means that such conservation strategy doesn’t necessarily negatively influence the population from which the individuals are taken. Also, the ongoing pest mammal control in the Hawdon Valley could have balanced the negative effect of the translocation. I guess the only thing left to do now is find out what makes kiwi desire those territories so much that they can’t stay away: maybe they have the most delicious earthworms of New Zealand?

    To conclude, these findings demonstrate that the species is reacting well to this reintroduction programme, considered that kiwi presence increased in the Nina Valley too. Furthermore, this study showed that combining occupancy estimates through statistical models with acoustic monitoring is very useful when studying the outcomes of kiwi’s translocations. However, if you, reader, can’t wait to know more about what happens to our dear kiwi when we move them around, sit back and read Peter Jahn’s PhD thesis: never stop learning.

    Finally, going back to my mum trying to “detect” me: I suggest the probability would increase a lot if she learned to call outside of my usual napping times!

    This article was prepared by Master of International Nature Conservation student Francisco Bini as part of the ECOL608 Research Methods in Ecology course.

    Jahn, P., Ross, J. G., MacKenzie, D. I., & Molles, L. E. (2022). Acoustic monitoring and occupancy analysis: Cost-effective tools in reintroduction programmes for roroa-great spotted kiwi. New Zealand Journal of Ecology, 46(1), 3466.

  • The hotspots are where it’s at if you want to spot a cat: the search for the common leopard

    The Himalayas are an almost mythical place, where mountains loom and the clouds surf down their sides before sliding into the forests below. The songs of rhesus monkeys, palm civets, and the occasional jackal sing out from the thick trees. This landscape is beautiful yet rugged. Travelling through is difficult for our human capabilities, in many cases impossible.

    Now imagine. This is the backdrop you must navigate to discover the number of big cats that live there. To top it all off, your target is the shyest and one of the rarest of them all, the inappropriately named common leopard.

    A common leopard relaxing in the sun
    (Source: Daily Pakistan: Pakistan’s common leopard endangered due to loss of habitat)

    Now, it’s not unusual that scientists doing field research are thrown into difficult situations. You might end up with dangers like Carlos Jared who innocently picked up a frog while doing fieldwork in Brazil, discovering frogs can be venomous. Or you might accidentally glue yourself to a crocodile while attaching a radio transmitter like Agata Staniewicz did (find that and more hilarious field research fails here).

    But when you’ve got a shy animal, add in an impassable landscape, plus the addition of the very real and dangerous threat of bumping into rebels which is, unfortunately, the reality in parts of Pakistan, you’ve really got your work cut out for you.

    This momentous task is one Muhammad Asad, PhD student at Lincoln University, took on as he bravely set off to northern Pakistan. Nobody had done this before and the leopard landscape was mostly unknown. But he was up for the challenge.

    The not-so-common leopard

    Leopards are found all over the world, the most widespread of all land-based carnivores. They’re incredibly adaptable, able to make their homes in all sorts of climates: from the savannas of Africa, the tropical forests of South East Asia, to the freezing mountains of far north Russia. They even make it work when humans move in.

    Their only request, being rather introverted, is that they have lots of space. They’re very territorial, protecting their home range fiercely. But honestly, a bit of peace is a reasonable request!

    Despite this incredible flexibility, common leopard populations are in decline. They’re no longer found in 63-75% of their historic range. The decline in Asia is even bigger, with an 83-87% drop! It’s no surprise that these gorgeous cats are listed as critically endangered.

    The majestic common leopard
    (Source: Daily Pakistan)

    Leopards are facing many different threats. The main ones are:

    • habitat is lost or changed,
    • trees cut down,
    • inbreeding from being cut off from one another,
    • human developments being built near their protected ranges,
    • prey disappearing,
    • poaching,
    • and human-wildlife conflict.

    Clearly, these cats need protection. So, leaving New Zealand and heading back to his native Pakistan, Muhammad took the first step to build a conservation plan; he had to figure out how many leopards there were and where they were found.

    To do this across the entire country would be too big a job. Instead, he focussed on the Gallies and Murree Forest Division in northern Pakistan, lying in the outer Himalayas. Here, leopards are protected under the law. Even so, there are often no checks for this, with hunters easily getting away with it. This is made worse by the slow and sometimes non-existent compensation programmes, programmes designed to reimburse farmers who have lost livestock to a leopard attack. The locals often resent the leopards. But it’s hard to blame them when people, including children, are occasionally attacked and killed.

    Leopards are poached frequently in Pakistan. Cubs are trapped to sell in the illegal pet trade or body parts and skin are taken for sale. Skin, claws, and teeth are sold in north Pakistan.
    (Source: Raj K Raj/Getty Images)

    Estimating the number of leopards in an area is very tricky. They have large territories with very few cats within each area. Figuring out where to look, especially when the landscape has the worst access, is the key to success.

    How to find leopards

    Muhammad and his crew began with a questionnaire survey. They asked people from local communities who lived nearby to fill these out. They asked about losses of livestock, when the attack happened, and the type of injury, for example, bite marks on the neck, missing dogs, or human casualties.

    Based on the information from the locals, they ended up with 63 different sites where they could focus the leopard hunting efforts. A much better start!

    Next, they moved into these sites, peeling their eyes for signs of poop, territorial markings (such as peeing on a tree), and tree scratches. These signs meant one thing; here be leopards.

    With this proof, they set up special cameras, known as camera traps, on either side of the trail, ready to capture the cats on the silver screen.

    They also set up cameras on 5 connecting trails which hadn’t shown any signs of leopard action. These were used to see if they could capture leopards in areas where they had left no signs. As new leopard trails were discovered, the camera traps were moved to snap those too.

    Sampling locations of the camera-traps survey in Gallies Forest (Ayubuia National Park, surrounding Reserved Forest and Guzara Forest), and Murree Forest (Protected, Reserved and Municipal Forest). Country map (top left – green). Study area showing different city boundaries (middle left).
    (Source: From paper)

    A leopard can’t change its spots – a handy identification tool

    You may have heard the proverb that a leopard can’t change its spots. This is supposed to teach us that we all stay true to our nature, even if we pretend we’re different. But it turns out when it comes to leopards it’s 100% true! The coat of a leopard is as unique as our fingerprints. Incredibly useful when you’re a scientist trying to tell the difference between two cats in a grainy photo!

    Their gorgeous spots are a bit like the shape of a rose, giving them the name ‘rosettes’. This means that by matching up the images of the rosettes you can figure out if it’s the same cat. The best place to match things up is on either side of their back legs or the top of their tail.

    Example of an individual being identified using the rosettes on the tail
    (Source: From paper)

    This is trickier than it sounds. The rosettes change shape as the leopard moves. And it can look different depending on the angle it is to the camera. But still, it’s a pretty helpful method to avoid double-counting cats. Double counting would give you a very different population size! You can find out more information on leopard identification techniques here.

    Example of when the spots don’t match up.
    (Source: From paper)

    So, how many are there?

    In 2017 Muhammad estimated there were between 16-24 common leopards in the Gallies and Murree Forest Division. This went down to 7-12 in 2018.

    However, they don’t think the population dropped. In 2018 they got fewer clear images making it harder for them to identify the cats. They think the real number could be closer to 12-18, meaning its range overlaps with the 2017 estimate.

    But, this might not be the case. In 2018, Pakistan was suffering from a drought. Perhaps the leopards had been forced to move out of their territories to look for food. So far there hasn’t been any research on leopard movements in relation to strange weather. This would be an interesting thing for someone to look into (are there any leopard enthusiasts up for the task?).

    Or perhaps this drop is real. Poaching and unreported killings are still huge in Pakistan. Plus, Muhammed and his team did find signs of hunting. So the reason could in fact be nefarious.

    Regardless of the reason, Muhammad estimated there to be 8-12 leopards and 3.5-6.5 leopards per 100 km2 in the Gallies and Murree Forest Division. They also confirmed they lived in the Swat, Dir, and Margalla Hills, even though locals as well as wildlife departments thought they had disappeared.

    These estimates are not 100% accurate. But the team is pretty confident that they are close to the true number. All in all, a great success.

    Mother common leopard and her cub.
    (Source: Daily Pakistan)

    What next?

    Now there’s a basic understanding of how many leopards there are and where they like to hang out, we can start to protect them.

    With this information, we can:

    • Use the leopard hotspots to keep an eye on the population trends and demographic changes over time.
    • Decide on the most important conservation areas. Special attention should be given to the corridors that join areas together to protect the long-term health of the leopard populations.

    For example, Muhammad discovered that 70% of leopards killed for revenge in the Guzara Forest happened outside of the Reserve area, close to the village, and in winter. That tells us we should focus the conservation efforts on the hotspots in the Guzara Forest surrounding the Reserved Forest so that human-leopard conflicts can be reduced.

    There’s still a lot of work ahead for the common leopard in Pakistan. But with Muhammad on the case, their future is looking a little brighter.

    You can read Muhammad’s research in full here: The Un-Common Leopard: presence, distribution and abundance in Gallies and Murree Forest Division, Northern Pakistan

    This article was prepared by Master of International Nature Conservation student Kat Douglas as part of the ECOL608 Research Methods in Ecology course.

    Full citation: Asad M, Waseem M, Ross JG, Paterson AM (2019). The Un-Common Leopard: presence, distribution and abundance in Gallies and Murree Forest Division, Northern Pakistan. Nature Conservation 37. 53-80. https://doi.org/10.3897/natureconservation.37.32748

  • I see you: Sauron and the panda

    “I wish we could get away from these hills! I hate them. I feel all naked on the east side, stuck up here with nothing but the dead flats between me and that Shadow yonder. There’s an Eye in it. Come on! We’ve got to get down today somehow.” JRR Tolkien, The Lord of the Rings

    We’ve all had that feeling of being watched, of something that has taken an interest in what we are doing, and not perhaps with our best interests. It makes us fell uncomfortable, awkward, and we often change our behaviour in response, become more cautious, less spontaneous.

    Tolkien knew the power of the watching individual. Sauron, the chief antagonist in The Lord of the Rings, is literally portrayed as the Great Eye – “The Eye was rimmed with fire, but was itself glazed, yellow as a cat’s, watchful and intent, and the black slit of its pupil opened on a pit, a window into nothing. Then the Eye began to rove, searching this way and that; and Frodo knew with certainty and horror that among the many things that it sought he himself was one.” Knowing that someone can see you wherever you are is about as big a threat as we can imagine, whether it is Sauron, your boss, or your mother! We generally hate the concept that someone is watching us.

    Tolkien loved the word ‘watch’ (he used it over 330 times in the Lord of the Rings!). The watch-tower of Weathertop is the site of Frodo’s wounding, a Watcher-in-the-water nearly ends the journey at the entrance to Moria, there are Silent Watchers at the gates of Cirith Ungol, the menace of the Old Forest, Fangorn (known as the Watchwood to the Ents). Threats are usually described in the language around the feeling of being watched. And it works, it quickens the pulse of the reader. We know the feeling and respond.

    Ever get that feeling that something was looking for you?

    The problem with knowing that you are observed (or can be observed) is that you behave in ways that are different to your normal behaviour. Many species will respond to observation by not performing rarer sorts of behaviour, like play or reproduction, or by moving away from the observer.

    Gollum knows all about the watching eye and this makes him much more cautious in his movements. “His Eye watches that way all the time. It caught Smeagol there, long ago.’ Gollum shuddered. ‘But Smeagol has used his eyes since then, yes, yes: I’ve used eyes and feet and nose since then. I know other ways. More difficult, not so quick; but better, if we don’t want Him to see. Follow Smeagol! He can take you through the marshes, through the mists, nice thick mists. Follow Smeagol very carefully, and you may go a long way, quite a long way, before He catches you, yes perhaps.’ Gollum scuttles about because he does not want to be observed.

    Frodo, under the wearying influence of the ring as he stumbles through Mordor, almost completely changes his normal behaviour under the threat of constant detection. “Anxiously Sam had noted how his master’s left hand would often be raised as if to ward off a blow, or to screen his shrinking eyes from a dreadful Eye that sought to look in them. And sometimes his right hand would creep to his breast, clutching, and then slowly, as the will recovered mastery, it would be withdrawn.” If not for Sam, who does not have this anxiety, Frodo would not make it to Mt Doom.

    In animal behaviour we have a similar problem. We usually want to observe an animal’s ‘normal’ behaviour but they will often change their behaviour if they can see a human watching them. Today, technology can come to our aid.

    Yes, yes we realise you are the cutest species… Red Panda resting. Image from Kat Bugler.

    One of the more powerful new-ish tools available to those that study animal behaviour are trail cameras. These devices allow us to observe animals in the field 24/7 (just as long as they wander past the unsleeping gaze of the lens and trigger the image capture). This is a huge improvement for behavioural studies, as we can watch without the actual presence of human observers. We have used cameras in many studies here at Lincoln, mostly in understanding the life history and behaviour of nocturnal mammalian pest species..

    Recently, we used trail cameras to find out more about red panda in Nepal. Cameras were placed on red panda latrine trees (which are exactly what you are imagining). We were able to record activity patterns of wild red panda in their natural environment. Such data is useful in working out management plans to help with their conservation. We were also able to record other wild species that share their habitat.

    In some of these captured images, it appeared that the red pandas were looking at the trail cameras. If they are aware of the cameras then this might alter their behaviour. Maybe they are curious and spend more time loitering in the areas? Maybe they are frightened and don’t behave in their normal way?

    Kat Bugler, as part of her MSc at Lincoln University (with supervisors Adrian Paterson and James Ross), decided to examine whether red pandas were camera shy. Kat was able to get permission from zoos in New Zealand and Australia to observe their captive red panda in their enclosures. Each habitat was different but Kat was able to set up trail cameras to record behaviour around the main activity areas and platforms. She had a more powerful camera set up out of the enclosure to record behaviour of the pandas in these areas and around the trail cameras. Kat also spent time recording her own observations.

    Trail camera setup in a zoo enclosure. Image from Kat Bugler.

    In a paper published in Animals, Kat was able to show that there was a difference in red panda behaviour when a human observer was watching them, compared to a camera. When red panda were being watched by an individual they defecated less, ate less, moved less, played less, rested less, and slept more than when they were only being ‘watched’ by the trail cameras. Red panda were much slower to change behaviours when being observed. Interestingly, there were similar differences, if not as large, when comparing behaviour recorded by the outside camera compared to the enclosure trail cameras. The presence of people changes red panda behaviour, but so does the presence of a trail camera.

    These are subtle changes. Trail cameras are hardly the eye of Sauron: “And suddenly he felt the Eye. There was an eye in the Dark Tower that did not sleep. He knew that it had become aware of his gaze. A fierce eager will was there. It leaped towards him; almost like a finger he felt it, searching for him.” Are trail cameras useful for monitoring red panda behaviour if they can cause changes in behaviour? Absolutely, they do record all of the behaviour that red pandas exhibit, they just may alter the duration and frequency of occurrence. As long as we bear that in mind then we have a great tool to use in the wilds of the Himalayas and in understanding more about the red panda.

    “He did not feel invisible at all, but horribly and uniquely visible; and he knew that somewhere an Eye was searching for him” Maybe Sauron would have been better off putting trail cameras on all of the paths into Mordor!

  • 1080 reasons for optimism

    Photo overlooking Mount Summers (Jan 2022). Image by Chida Chapagain.

    It’s good to be optimistic. I have always been hopeful about the future. I lived the first 11 years of my life in a refugee camp. Times were tough, but I knew things could only get better. Even as a child, I knew there was more to this world than what I had experienced.

    Fast forwards a couple of years, and my family and I are living in New Zealand, happier than ever. The first 11 years in Nepal, compared to my last 11 years here in New Zealand, have been extremely different. My life changed for the better.

    Sometimes I wonder what would have happened if my family had moved to America or Australia instead of New Zealand. I often catch myself saying, “maybe my life would have been even better?” Optimism combined with curiosity can be a powerful motivator, leading us to explore the unknown. But we must be realistic with our expectations. Just because we are optimistic about the unknown doesn’t mean it must be true. There will always be challenges and limitations. Nothing is, or will ever be, perfect. 

    The same applies to alternative pest control methods being developed in New Zealand. The pest control toxin 1080 has its concerns, as do alternative methods that have been or are being developed. 1080 is a fully developed method that has been repeatedly shown to control introduced pest mammal populations on a large scale.

    The common brushtail possum (Sept 2010). Photo by Daniela Parra from Flickr.

    While it may not be perfect, it is widely recognised among scientists and conservationists that 1080 is currently the best tool we have for pest control. The use of 1080 is essential in protecting our native flora and fauna. However, we should always be looking to make improvements, but until such progress is made, the use of 1080 must continue. Perhaps you’ve read other things about 1080 and don’t agree. Allow me to explain.

    Bruce Warburton, Penny Fisher, Brian Hopkins, Graham Nugent, and Phil E. Cowan of Manakai Whenua Lanacare Reserach, along with James Ross of Lincoln University, outline the major areas of concern raised by 1080 and summarise the changes that have been made to the use of 1080 to address these concerns.

    The main four concerns related to the use of 1080 have been:

    1. the potential environmental and human health risks,
    2. the limited control over where the bait lands when applied aerially,
    3. the lack of species selectivity, and
    4. the animal welfare impact on target and non-target species.

    They explore the impacts of 1080 use for conservation and bovine tuberculosis (TB) control. They then summarise alternative toxicants and methods for mammal pest control being investigated in New Zealand. Then they address to what extent these alternative methods might be able to address the concerns raised by 1080 opponents. This article may alter your views on 1080.

    1080 is the current best tool we have for our unique fauna!

    Sodium fluoroacetate (1080) has been a recognised pesticide since the early 1940s. 1080 is most frequently mixed into cereal baits for possum and ship rat control. New Zealand is the world’s largest user of 1080. The extensive use of 1080 in New Zealand is made possible by our unique fauna, where we have 35 introduced mammal species and only two native terrestrial mammals (both bats).

    Introduced mammals, such as rats, possums, and stoats, are widespread and have significant impacts on native biodiversity and/or agricultural production. They continue to damage and threaten native and endemic species at unacceptably high rates.

    Māori believe ‘failure to act falls short of our responsibilities to our ancestors, and future generations’. Fortunately, 1080 is a very efficient method for pest control. Monitoring by the Department of Conservation (DOC) before and after aerial 1080 operations targeting possums, rodents, and stoats has repeatedly shown consistent benefits for nesting success in kiwi, kea, kaka, whio, pīwauwau, mohua, and tītitipounamu. O’Donnell and Hoare in 2012 found native bird populations to have doubled after more than 20 years of sustained predator control. 

    North Island Saddleback (Oct 2021). Photo by Geoff Mckay from Flickr.

    Are the ‘concerns’ about 1080 fact or evidence-based?

    There are concerns and opposition to the use of 1080. Some are evidence-based. 1080 does kill non-target species. According to Dave Hansford, about 12% of radio-tagged kea died after aerial 1080 operations. In 1970, there was a ministerial review of the properties, effectiveness, and regulatory control of 1080. The review supported the use of 1080 but also recommended areas for improvement. Most of these recommendations were implemented, but opposition to its use remained.

    In 2006, there was another formal assessment of 1080. Once again, the use of 1080 was permitted. 1080 opponents were still outraged. This triggered another investigation by the Parliamentary Commissioner for the Environment (PCE), who is tasked with providing independent advice to the government. The PCE concluded that “not only should the use of 1080 continue, but that we should use more of it.” Justified concerns about 1080 have been thoroughly reviewed many times, and these reviews have refined the ways in which 1080 is used safely to benefit the NZ environment. The remaining strong opposition to 1080 use by some New Zealanders has required that a lot of time and money being spent on developing, testing, and registering alternatives to 1080. 

    What are these alternative pest control methods?

    There are many alternative methods for pest control. However, many of these are not feasible for our unique situation. For example, shooting is not a viable method for small mammals like mice and rats, and it is too expensive to apply on a large scale. Trapping, similarly is not cost-effective for large-scale operations, especially in the more remote, mountainous parts of New Zealand. Although these methods can complement 1080, they cannot achieve the levels required for effective large-scale conservation. New toxins, including zinc phosphide, sodium nitrate, coumatetrayl, and diphacinone, have also been registered for use. However, none have been developed for aerial use.

    Genetic methods have the potential to drastically reduce the population of mammalian pests. There is a lot of attention on “gene drives”, which are engineered using the CRISPR/Cas9 genome editing technology. The gene drive DNA sequence, typically for reduced fertility, is then interwoven into the genome of an individual organism of the pest species, and every offspring of that individual inherits this modified DNA. One individual with this deleterious gene could potentially lead to complete eradication. This is the most promising alternative to 1080 in terms of cost and efficacy. There is, however, be significant scientific and public scrutiny to be done on this method.

    In the meantime, our birds are continuing to be eaten by pest mammals.

    My final thoughts

    Having lived in both Nepal and New Zealand, I have been able to witness many beautiful birds. Nepal is home to the Himalayan Monal, which is my favourite. I vividly remember chasing this colourful bird around as a child. New Zealand is also home to many beautiful birds. We cherish these birds; they are part of us. However, today, many of them face the risk of extinction.

    I am not an expert in pest control, but, I understand that without pest control, conservation programmes would fail. Reviews after reviews have shown that 1080 is the best current pest control method we have for introduced predatory mammals (possums, mice, rats, stoats, weasels) in New Zealand. Until we have better options, we need to continue using the best tools because our endangered endemic species cannot wait. We are lucky to have a pest control method that has proven to be so effective. It’s good to be optimistic.

    The author Chida Chapagain is a postgraduate student in the Postgraduate Diploma in Applied Science taught at Lincoln University. This article was written as an assessment for ECOL 608 Research Methods in Ecology.

  • Fishing for possum DNA

    When I was a child, I was fixated on animals. In fact, 5-year-old me would go around telling all the primary school mums that I wanted to be a Palaeontologist. This was often met with some strange looks, quite possibly because they didn’t even know what a Palaeontologist was themselves. Since then, I have been less focused on digging up dead animals and more interested in protecting the ones that are still alive.

    In New Zealand, tourism and agriculture are arguably the biggest money-maker industries. People flood from overseas to check out the clean green image being advertised in their home countries for themselves. The ‘Great Walks’ lead tourists through the rugged bush that New Zealand has to offer. Along the way they might even see some of our diverse flora and fauna, of which most can not be found elsewhere on Earth.

    On the other hand, the dairy, sheep and beef industries in New Zealand, earn large amounts of overseas revenue. This all started when Samuel Marsden introduced shorthorn dairy cattle to New Zealand from New South Wales and the rest is history.

    https://www.australiangeographic.com.au/topics/wildlife/2017/04/killer-possums/

    This brings me to the devious, but very cute looking, Brushtail Possum, Trichosurus vulpecula. In Australia, the Brushtail Possum is a protected species. In New Zealand they are a serious threat to our homegrown species. Possums compete with our native bird species for food and inhabit the same areas. These fluff balls are omnivores. In addition to eating the leaves off trees, they rob the nests of birds and eat the chicks and eggs.

    Bovine tuberculosis is a disease that affects many farm animal species. Possums are the biggest carriers of tuberculosis and can infect herds of dairy cows, causing serious illness to the animals and a large vet bill for the farmer. Due to these factors, New Zealand tries incredibly hard to get rid of these furry mammals. One important thing that we need to know is where these possums are present and and in what numbers. For a nocturnal and relatively cryptid species, this is a lot harder to do than simply call a roll!

    The use of trace DNA to monitor animals, such as possums, is a relatively new concept. However, a trial was held in Canterbury where researchers collected DNA from saliva left on WaxTags and Chewcards to determine the number of possums in an area and check whether these individuals were Tuberculosis carriers. From the initial field study, it was found that multiple possums would bite the WaxTag and Chew cards which made it difficult for the lab team to isolate certain animals. A new device to collect data was needed.

    A mechanical collection device was created which would remove the bait after one animal had bitten into it, which protected the saliva and therefore the individual DNA could be distinguished. The device was a bit like a fishing line, catching its prey and then reeling in the DNA! Researchers found that the mechanical device allowed the DNA to be collected and more easily sequenced. They also found that the genetic material was more easily recovered from covered WaxTags than on the uncovered WaxTags.

    Mechanical device created to protect DNA sample on the WaxTag. Image from: A New Non-Invasive Method for Collecting DNA From Small Mammals in the Field, and Its Application in Simultaneous Vector and Disease Monitoring in Brushtail Possums
    Mechanical device created to protect DNA sample on the WaxTag.
    Image from: A New Non-Invasive Method for Collecting DNA From Small Mammals in the Field, and Its Application in Simultaneous Vector and Disease Monitoring in Brushtail Possums

    Cameras used in the field trials picked up that the possums interacted with the new WaxTags, and 87% of the devices were triggered after the first interaction. This is a positive point because in order for a monitoring device to be useful, the target has to interact with it.

    This new way of collecting trace DNA samples was a success. DNA from Brushtail Possums was able to be amplified for genetic identification and was able to detect if diseases were present. The combination of the device being interesting enough for the targets to interact with, and the subsequent DNA extracted being protected until collection, means that it is ever more likely that technology like this can be used for other pest species to determine their disease risk.

    The current study is the first to collect trace amounts of possum DNA and keep it protected from the elements until genetic analysis has taken place. This is a pretty big step for DNA collection methods. However, transmission of infectious diseases by vectors, such as possums, is density dependant. More collection devices need to be installed in these areas being studied to create ‘encounter’ history for individuals to determine population density and to calculate the likeliness for for transmission of these vector carried diseases.

    This research suggests that there are new ways for non-invasive monitoring pest populations. The road to New Zealand being predator free by 2050 is a long one, but is shortened by the impressive new technologies being developed in the pest management space. This technology is key for determining the populations of pests in their area and how likely their livestock are to contracting devastating diseases such as Bovine Tuberculosis.

    Dealing with pests may not be the most fun thing to do week to week, however, determining where populations are and where the risks lie can help experienced personal to more effectively manage pest populations and get New Zealand back to where we should be, mammal predator free.

    This article was prepared by postgraduate student Rebecca Anderson as part of the ECOL608 Research Methods in Ecology course.

    Emami-Khoyi A, Agnew TW, Adair MG, Murphy EC, Benmazouz I, Monsanto DM, Parbhu SP, Main DC, Le Roux R, Golla TR, Schnelle C, Alizadeh H, Csányi S, Heltai M, Jansen van Vuuren B, Paterson AM, Teske PR and Ross JG (2021) A New Non-invasive Method for Collecting DNA From Small Mammals in the Field, and Its Application in Simultaneous Vector and Disease Monitoring in Brushtail Possums. Front. Environ. Sci. 9:701033. https://doi.org/10.3389/fenvs.2021.701033

  • Nosy predators check out the competition

    Growing up in New Zealand, I had a great passion for animals. Viewing everything through a child’s eyes, I believed that all wildlife should be free to thrive anywhere they wanted. Today I see the realities of the world were all animals are cherished, but some are out of place and others are vulnerable. I am not alone in realising the endangerment and damage that pest species can cause to our native species. This awareness has me seeking to understand the appropriateness of eliminating certain species from particular locations in order to protect others.

    The flora and fauna within New Zealand are some of the most remarkable in the world. A large majority of the animals and plants (and fungi) are endemic, or unique, to New Zealand. Over the years, many species have been introduced to New Zealand, such as ferrets, stoats, hedgehogs and ship rats, that have put these unique animals and plants at risk. It has become vital that monitoring and control of these predators is implemented to allow our native species a greater chance of survival.

    Research to improve strategies and techniques to monitor and remove these predator species has been underway for many years now. One method used to monitor these predators is through deploying food-based lures that attract the target animals to traps or cameras. This allows for observations to be made in order to determine the density of these species in the surrounding area, as well as to increase the chances of trapping and removing these animals.

    One way to attract these predators is to use odours from more dominant predators to attract the target species to the traps or cameras. This technique is based on the observation that mammals, like stoats and rats, use scent as their primary sense to forage for food and detect dominant species (higher ranking species than themselves). Dominant species directly influence the behaviour of mesopredators (mid ranking predators) by either attracting them or repelling them away from the odour. A dominant predator’s odour may provoke the subordinate (lower ranking predator) into preforming eavesdropping behaviour. This behaviour is used by species to inspect the location where the dominant predator has roamed. If the location is good enough for the big, tough predator then maybe it is a good place for the subordinate as well.

    Researchers from Lincoln University, University of Auckland and Landcare Research chose to test ferret odour verses fresh rabbit meat (a traditional lure) for stoats, hedgehogs and ship rats. This study took place at Toronui station, a 1500 hectare sheep and beef farm located in Northern Hawkes Bay. It lasted for 64 days trial.

    From left to right; Stoat (Mustela erminea), Hedgehog (Erinaceus europaeus), Ship Rat (Rattus rattus) and Ferret (Mustela putorius furo), all mammalian predators introduced to New Zealand. Charlie Marshall, (CC BY 2.0), https://www.flickr.com/photos/100915417@N07/49407663736; Jesus Duarte, (CC BY-NC-ND 2.0), https://www.flickr.com/photos/26795194@N00/8897432606; Amanda and William Explore, (CC BY-NC 4.0), https://www.inaturalist.org/observations/120567285; Max Moreau, (CC BY 2.0), https://www.flickr.com/photos/9426349@N07/6085681724.

    The results from this trial confirmed that the ferret odour was the best for attraction, at least for stoats and hedgehogs, while rats avoided the ferret odour. Other studies have also found that rats avoid fresh odours. Stoats showed the strongest attraction to the ferret odour, with double the number of stoats being observed at the monitoring stations compared to fresh rabbit meat. These results can lead to exciting new possibilities to improve the monitoring and management of these species, especially in places where they are predicted to be rare.

    One surprising result that was found was that the population of stoats at Toronui station before the study began was estimated to be rare. After the study was completed, the stoat population was predicted to be widespread. This makes you wonder just how underestimated the population of stoats in New Zealand really is.

    Studies like this are important as New Zealand. With very limited native mammals, the native species, such as birds and insects, within New Zealand have had no need to adapt to mammalian predators. As a consequence when predator mammals were introduced into New Zealand they caused devastating damage to the endemic species.

    Ferret odour lures were found to last longer than the fresh rabbit meat lures. This means that the ferret odour lures can be left out in the field for a longer period of time and still work just as well. Rabbit meat lures become ineffective faster leading to underestimates of pest populations.

    The finding of the effectiveness of ferret odour as an attractant, especially in stoats, introduces a new tool and opportunity for pest management and conservation. It opens up many paths for future research to develop and learn more about this type of monitoring and the positive effects that it could have on our native species. More recent work has reported similar outcomes.

    Mammalian predators are a major threat to the unique biodiversity that we have in New Zealand. New discoveries, such as the use of dominant predator odour in predator removal, gives me hope that there is a future for our taonga, native species.

    The author Stacey Lewthwaite is a postgraduate student in the Master of International Nature Conservation taught at Lincoln University. This article was written as an assessment for ECOL 608 Research Methods in Ecology.

    Garvey, P. M., Glen, A. S., Clout, M. N., Wyse, S. V., Nichols, M., & Pech, R. P. (2017). Exploiting interspecific olfactory communication to monitor predators. Ecological Applications, 27(2), 389-402.

  • The spitfire: a sure-fire way to eradicate stoats?

    Stoat! Look out, the RAF (Really Awesome Field-research) is coming! Photo CC BY-NC 2.0 Stuart Smith, Flickr

    Stoats, weasels and ferrets: the terrifying trio. If New Zealand’s native birds could speak, I’m sure that’s how they would refer to them as they swap stories of escape and near misses. Widespread, wily and lethal, the stoat is considered the greatest threat to the survival of many endangered and threatened native birds on the mainland, such as the takahe, orange-fronted parakeet, and Leonardo DiCaprio’s favourite, the kakī (black stilt).

    Here are the cold, hard facts. Humans introduced stoats from Europe to control rabbits in the 1880’s, against the advice of ecologists at the time. They have since run rampant over our native bird species, throwing many populations into a drastic decline. Like clever little kleptomaniacs, they sleep on beds of feathers stolen from our most treasured and rare birds.

    We must eradicate stoats from areas of New Zealand if we are to have an extant bird as our national icon. The prevailing question is, how?

    Photo CC BY-NC-ND 2.0 Shellie Evans, Flickr

    Never fear, the Spitfire is here! Unless you are a stoat then, yes, be afraid. The Spitfire is a re-setting toxin delivery device which was trialled in the Blue Mountains of Otago in 2013. 65 Spitfire devices were set up for approximately six weeks. Each device was capable of delivering 100 lethal doses of the stoat killing toxin PAPP (para-aminopropiophenone).

    The stoat population was monitored in the area during this time using trail cameras and tracking tunnels in order to measure the Spitfire’s effects.

    The project was carried out by Elaine Murphy, Tim Sjoberg and James Ross from Lincoln University, along with researchers from Wildlands, the Department of Conservation and Connovation. They found that the Spitfire knocked down 62% of the stoat population in the trial area.

    The Spitfire is a very picky individual, only delivering the lethal dose of poison to a suitor of the right body size and shape. The device is able to do this due to its dual sensors. Cameras trained on the Spitfire devices during the trial in Otago recorded no instances of non-target species, such as rifleman, receiving any of the poison. PAPP has been registered for use in stoat control since 2011, but is mostly available for use in fresh meat lures, which are labour intensive to produce and expire quickly.

    The 2013 trial was a success for the Spitfire and PAPP, but it was not without it’s issues. It was a trial after all! Many of the devices malfunctioned before the end of the six week trial due to design faults in weather proofing and circuitry. The conclusion was that the Spitfire showed promise, but lacked in stamina and sturdiness.

    Kereru in Kawakawa, Photo CC BY 2.0 Geoff McKay, Flickr

    All was not lost! In 2016 the New Zealand Government announced its goal to become predator (rats, mustelids and possums) free by 2050, which led to a funding initiative called ‘Products to Purchase‘ from PF2050 Ltd. Five products were selected, based on their expected contribution to the cause, to receive funding to fast track their development to a marketable level.

    In 2019, the first five successful applicants were named, and who should be among them but our voracious Spitfire. A Tauranga based start-up called Envico Technologies Ltd (ECT) went back to the drawing board with the device. They re-engineered and re-invigorated the design and produced a prototype they could now commercialise, all with the help of the funding from PF2050 Ltd.

    The Spitfire was back in the game, with the new design finalised in 2020. The latest model promises a longer lifespan of one year, during which no maintenance or refills are required. It’s widely known that the main cost in stoat control is in the field hours with bait station and trap operations, so this hands-free option is looking like an economical as well as an effective choice.

    Also on the toolbelt of the new Spitfire model is a bluetooth data logger, which records the date and time of trigger events. ECT envisions this feature being highly beneficial for monitoring pest populations and assisting with re-invasion events in eradicated areas. Because of it’s long field life, the Spitfire becomes an attractive option for use in more remote areas where previously the only viable option has been aerial 1080 drops. If you have a ‘Ban 1080’ bumper sticker, this product may be for you.

    Brushtail possum and her joey at Tārerekautuku Yarrs Lagoon, Photo Katherine Turton.

    Just when you think it can’t get any better, a distinct advantage of the Spitfire is that there are few issues with alternative food sources or bait shyness. Stoats don’t have to bite, pull, stand on a treadle, or count backwards from 100 to receive a lethal dose. They are simply drawn in by an automatic lure dispenser that keeps a delicious mayonnaise paste coming all year-round.

    The Spitfire is an intellectual. It has smart capacitive sensors that can detect and measure anything that is conductive. It can tell the difference between the long sausage body of a stoat and a little compact rifleman, preventing our inquisitive native species from receiving the toxin. When the Spitfire senses a stoat it launches a lethal splurge of toxin onto the abdomen, after which the animals are instinctually driven to groom off the mess.

    ECT joined forces with the Department of Conservation and Boffa Miskell to conduct field trials from 2020-2022. Alongside the stoat design, a model specifically for our Australian foes, the brushtail possum, was also trialled using a Diphacinone and Cholicalciferol toxin instead of PAPP.

    Field trials are about to conclude for the Spitfire and ECT are expecting to roll out the finished product at $200 a piece. There is also talk that a rat specific Spitfire is now in the works! This innovative technology is paving the way for more effective pest control not just here in New Zealand but worldwide. Conservation groups get your wallets ready and watch this space!

    For more information, see the article on the Sptifire trial in Otago and follow ECT to keep up with their latest technological solutions for conservation!

    This article was prepared by postgraduate student Katherine Turton as part of the ECOL 608 Research Methods in Ecology course in her Master of Pest Management degree.