EcoLincNZ

Month: July 2024

  • Finding a needle in a haystack: locating the short-tailed bat

    Most of us have been in the position where we’ve struggled to find something, be it your car keys, phone, or favourite pair of sunglasses. No matter how hard or long you search it just seems to elude you. One minute it’s there and the next it’s gone. You know it’s there, but where!! It’s an extremely frustrating feeling.

    This feeling is all too familiar to those scientists trying to monitor one of New Zealand’s bat species, the lesser short-tailed bat. These scientists would probably argue that finding small bats in a large forest has a few more challenges than searching for your car keys at home.

    Lesser short-tailed bat, Photo credit: CC-BY-4.0 Department of Conservation (NZ), via Wikimedia Commons

    To make monitoring the lesser short-tailed bat a bit easier it would be useful to know which parts of the forest they prefer to visit. Jessica Scrimgeour, Laura Molles, and Joseph Was looked into which forest structure lesser short-tailed bats are most likely to be found in. The scientists pondered over whether these elusive bats are in the forest they’re monitoring but they just can’t find them, or are they not in the forest at all.

    Most lesser short-tailed bat monitoring in New Zealand has occurred at ground level. However, scientists were aware that these bats can and do fly in all levels of the forest, from way down low to way up high. Bats may be hard to find when you are repeatedly looking in the same spot in the forest.

    Hard beech forest (Fuscospora truncata) in Ecclesfield Reserve, Upper Hutt, New Zealand, Photo credit: Rudolph89, Public domain, via Wikimedia Commons

    Back in 2013 Scrimgeour (Department of Conservation), Molles (Lincoln University), and Was (University of Waikato) used automatic bat monitors (ABMs) in the North Island to investigate this. ABMs are sound activated recorders that collect bat echolocation calls. ABMs can be set at different heights in beech and podocarp forests. Generally speaking podocarp forests are made up of trees of varying heights with a thick understorey. Beech forests on the other hand are made up of different beech tree species of a similar height, with a more open understorey.

    Lesser short-tailed bats prefer to fly through forests that have minimal clutter, or are the most open. ‘Clutter’ refers to, among other things, the amount of branches, leaves, and tree trunks that hinder the bats flight and echolocation.

    Echolocation is the bats way of navigating. It works by bats sending out sound waves that hit surrounding objects and then bounce back to the bat allowing the bat to orientate itself. In a cluttered forest the objects are very close together, which means that the bats are still sending out sound waves at the same time sound waves are bouncing back. Returning sound waves become challenging to interpret and can interfere with tasks such as orientating and finding food.

    Initially the group thought that a more cluttered forest would attract more bats, as clutter might mean an increase in biodiversity, with better quality food available. Even if the cluttered forest had the most food, which for bats is insects, they preferred to take the path of least resistance. Navigating through dense forest is just hard yakka, requiring too much energy. No surprises there, who doesn’t take the path of least resistance?

    Podocarp forest west of MacKay hut on the Heaphy Track, South Island, New Zealand, Photo credit: Pierre Lavaura, Public domain, via Wikimedia Commons

    Lesser short-tailed bats are very committed to taking the path of least resistance and even change the height they fly at depending on the type of forest they’re in. In the beech forest, bats spent the most time flying in the bottom tier of the forest, as this part was the least cluttered. In podocarp forest, bats spent most of their time flying in the least cluttered middle tier of the forest.

    As New Zealander’s we like to think that we are different to the Aussies across the ditch, but our bat species don’t quite think the same. The trans-Tasman bats are actually very similar to each other. Other research on bats in Tasmania found that bat flying activity is greater when the forest is more open. So I suppose you could say that the Tasmanian bats are a bit lazy like our bats, or they behave optimally!

    The results from this 2013 study have also been backed up in subsequent research in New Zealand. This research found that in urban and rural settings long-tailed bat activity was also effected by vertical airspace and horizontal microhabitats.

    For those on the lookout for bats this study has helped with deciding where to place monitoring devices for more robust monitoring programmes. Finding that needle in the haystack has just a little bit easier.

    Lesser short-tailed bat, Photo credit: CC-BY-4.0 Department of Conservation (NZ), via Wikimedia Commons

    What’s been happening with monitoring programmes for bats since 2013? Well, it turns out quite a lot. Acoustic monitors are now used instead of ABM’s. These monitors are basically microphones that record bat echolocation calls as they fly past the monitors. More research has gone into where bat activity is likely to be the highest to further help in the placement of acoustic monitors.

    This new knowledge has definitely paid off with the exciting recent discovery of a population of the lesser short-tailed bats in the lower North Island. It was thought that the lesser short-tailed bat was extinct from the Pākuratahi forest, Upper Hutt, because bats had not been detected there for a very long time. It just goes to show that just because you haven’t detected something doesn’t mean it’s not there. Sometimes you just need to look a bit harder or, at least, a bit smarter.

    Scrimgeour, J. Molles, L., & Waas, J. R. (2013). Vertical variation in flight activity of the lesser short-tailed bat in podocarp and beech forest, Central North Island, New Zealand. https://researchcommons.waikato.ac.nz/server/api/core/bitstreams/fe6c95f0-a86d-408b-a6b4-cbc112a24865/content

    This article was prepared by Postgraduate Diploma in Applied Science student Anna Gardiner as part of the ECOL608 Research Methods in Ecology course.

  • Jumping to the top of the world: new salticid spider species in the Southern Alps

    Spiders.

    Your reaction to that word might determine whether or not you finish reading this post, but try to bear with me — at least for a little while. While I can accept that most people aren’t nearly as fond of spiders as I am, I think all but the truly arachnophobic (it’s okay; I understand that you can’t help it) can agree that the jumping spiders are among the “cutest” and most acceptable spider groups. These active little hunters can often be found in or around the house, and their big binocular eyes and expressive “face” make them a lot more relatable than your average creepy-crawly. Well, most of them!

    A newly-described female Ourea petroides from the Ōtira River valley, Arthur’s Pass. © own work, 2022. CC-BY-NC.

    Jumping spiders, in the family Salticidae, are among the most well-researched spiders in the world, with over 6,500 species described. Meanwhile, the jumping spiders found in Aotearoa New Zealand – apart from the most commonly-encountered species – are very poorly known to science. There are thought to be around 200 species in NZ, with about 50 known well enough to be named. However, we can only reliably identify fewer than a dozen of them. Compare this with Australia, where hundreds of species are known already, and work to describe the rest is well under way.

    Not to be outdone by the Aussies, Lincoln University’s Robin Long, along with her supervisor Dr Cor Vink, decided to do something about that. For her Master’s project, Robin set out to catalogue and describe the jumping spiders found in some of NZ’s most remote and extreme environments: the rocky heights of the South Island’s alpine zone.

    Robin visited 21 different sites all over the Southern Alps, from Paparoa to Fiordland, collecting 170 jumping spider specimens (all by hand!) from up to 1,800 m above sea level — and logging some impressive hiking mileage in the process!

    Looking across the Ōtira River at a scree slope where Ourea petroides can be found, Arthur’s Pass. © own work, 2022. CC-BY-NC.

    Through DNA analysis and careful examination of microscopic features on each spider, Robin separated those 170 specimens into 12 new species, and determined that the group was so unlike others known to science that it represented a brand new genus (a group of closely-related species with a common ancestor). She named this genus Ourea because, like the ancient Greek mountain gods, many of the species were found to be associated with a specific mountain range.

    Many of NZ’s indigenous species are only found across quite small areas, often because of the (relatively) recent and rapid growth of our mountains — which even today continue to grow taller by around 7 mm per year. Formerly widespread species were split into separate populations by the tectonic uplift, and over the last few million years these now-isolated populations have diverged into new species. Robin’s jumping spiders, much like many other NZ alpine species, took advantage of the ample prey and new habitats created by the growth of these mountain ranges. Over time these spiders even developed cryptic colours and patterns that help to camouflage them against the particular rock types they live amongst.

    Magnificent moustache: a female(!) Ourea saffroclypeus from the Remarkables Range. © Robin Long, 2022. CC-BY-NC.

    Not content with merely describing a whole genus and a dozen new species, Robin also set about studying and describing the spiders’ behaviours when interacting with other members of the same species. Jumping spiders have exceptional eyesight, and are known for communicating with each other through visual displays that range from the bronze hopper’s simple leg-waving, all the way to the flamboyant, colourful dances (which often incorporate vibration as well) performed by the aptly-named peacock spiders.

    The four Ourea species that Robin observed in the lab each exhibited a unique set of behaviours when they met another spider, and these behaviours differed depending upon whether they met a member of the same or the opposite sex. Males postured fiercely at each other, squaring up in a face-to-face grappling contest with legs and fangs outstretched.

    When attempting to impress a female, males gestured with their legs and “zigzag-danced” their way closer, before attempting to reach out and gently stroke the female’s head. Perhaps unsurprisingly, this final move had quite mixed success! Females meeting each other were a bit more sensible, and usually made a few simple (though probably quite impolite) leg gestures at each other, before one or both turned away and went in the opposite direction.

    Despite the enormous amount of work that went into researching these spiders, Robin acknowledges that her almost 150-page thesis has only scratched the surface of the topic. Little is known of the spiders’ life histories or the individual species’ spatial distributions, and it’s “very likely” that there are additional species in the genus waiting to be discovered on other mountain ranges.

    Exquisite camouflage: Ourea petroides, Ōtira River valley, Arthur’s Pass. © own work, 2022. CC-BY-NC.

    Robin also suggests a similar study would likely uncover another distantly-related group of undescribed jumping spiders living quietly in the Southern Alps. This is a common problem with New Zealand’s invertebrate fauna: while we have a good general understanding of what’s around us, there are still huge gaps in our knowledge — and usually the studies that attempt to address this just end up revealing more unanswered questions!

    We have a rich history of brilliant people, like Robin, studying, documenting, and describing New Zealand’s unique invertebrate biodiversity, and there are still many new discoveries to be made in every corner of our little country. But, despite huge technological advances, research has dwindled in recent decades due to funding redirections and the restructuring of government services.

    Under the looming threats of climate change and habitat loss, we need to pay closer attention to the smallest and most enigmatic (if not always particularly cute) creatures that live alongside us, lest they disappear before we even have a chance to study them. Australia is well ahead of NZ in this regard, with funding and support for taxonomic studies provided through their world-leading ABRS scheme. I’m not much of a sports enjoyer, but beating the Aussies at this game is one trans-Tasman rivalry I could definitely get behind.

    This article was prepared by Bachelor of Science (Honours) student Dustin la Mont as part of the ECOL608 Research Methods in Ecology course.

  • Dirty little secrets or tiny heroes of the soil world?

    Dirt was one of my first friends. My earliest days were spent collecting worms from the backyard and trying to convince my parents I hadn’t done any dirt taste testing that day (I probably had, but for purely scientific reasons). I was fascinated by what seemed like an entirely different world in the soil of my parent’s garden. I could find all kinds of goodies from insects to plant roots.

    At university I was introduced to the truly magical world in soil: microbes. Although not visible to the naked eye, the tiny worlds inhabited by fungi, bacteria, viruses, and other unbelievably small things, should not be overlooked. These tiny worlds are called the microbial community and they have important roles in New Zealand forests.

    Photo of soil microbes under a microscope. Photo by Pacific Northwest National Laboratory (CC-BY-NC-SA 2.0)

    A good place to start thinking about microbial communities is our own bodies. Most people have heard of their gut microbiome. The microbes in our digestive system are important for our health from immune function to digestion (especially for dirt tasters). However, some microbes, such as the COVID-19 virus, can make us sick. Soil microbes in forests are not so different.

    Forests are dependent on microbes that cycle nutrients, decompose waster, and aid plants in nutrient uptake. Like humans and the common cold, some soil microbes hurt their associated plants. An example of this is kauri dieback disease, a disease spread by a spore in the soil that attacks tree roots and trunks. This disease hinders the tree’s ability to uptake and transport nutrients, essentially starving and killing the tree. Kauri dieback is incurable and fatal for kauri.

    Tāne Mahuta, the largest surviving kauri. Photo by Jodie Wiltse (Author)

    Kauri dieback is named after the tree it infects, New Zealand’s mighty kauri tree. The Department of Conservation explains that kauri can grow up to 16 m in circumference and live over 2000 years. The legendary status of kauri is clear in the language used to describe them. The largest surviving kauri is called Tāne Mahuta, which means ‘lord of the forest’. If you were to visit Tāne Mahuta today, you would find boot cleaning stations, warning signs, and only be able to view the great tree from a platform. Moreso, entire trails have been shutdown to stop people from spreading soil around kauri. Why?

    A soil microbe, Phytophthora agathidicida, travels under the name of kauri dieback. This microbe cannot be seen with the naked eye but has the power to kill tremendously large kauri trees. In humans, the heroic microbes of our immune system save us when nasty microbes make us sick. Are there unseen heroes hiding in the soil that can help kauri?

    During a PhD project at Lincoln University, Dr. Alexa Byers studied soil microbial communities under kauri to find out. The goal was to identify microbes that suppress kauri dieback and can aid in kauri conservation.

    The first step was to understand how microbial communities under kauri react to kauri dieback disease. Alexa infected kauri seedlings with kauri dieback and looked for changes in the soil microbial community. When humans are attacked by illness causing microbes, our immune system amps up to protect us. When soils were infected, Alexa found bacteria that were involved in disease suppression. This was a promising result suggesting that heroic soil microbes could build up their numbers to fight off kauri dieback.

    Kauri tree bleeding resin, a common symptom of kauri dieback disease. Photo by Onco p53 (CC BY-SA 4.0).

    Next, Alexa looked into how specific strains of bacteria from kauri soil impacted the development of kauri dieback. She identified Paraburkholderia and Penicillium microbes that inhibited the growth of kauri dieback in soils. Paraburkholderia are known to enhance plant growth and fix nitrogen. Penicillium are fungi that can kill or stop growth of other bacteria. We officially have some heroic contenders!

    The battles between heroic microbes and kauri dieback in the soil could determine the fate of the kauri above them. Hopefully, researchers can find a way to rig microbial battles in favour of these unseen heroes. More research is needed to determine their true potential, but these soil microbes could be called to action in the near future.

    The world under kauri is just one example of fascinating soil microbes. Soil microbes have been found to be key for carbon storage, impact the taste of tea, and reduce nitrogen runoff from agriculture, among many other amazing things. This is your reminder to appreciate the little things, even the things so little you cannot see them. Next time you play in a garden or walk through a forest, I hope you take a moment to think about all the tiny microbes working away in the soil to help (or hinder) plants and make the natural world work.

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

    Research Paper: Byers, A.K. (2021). The soil microbiota associated with New Zealand’s kauri (Agathis australis) forests under threat from dieback disease: A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University. Lincoln University. https://hdl.handle.net/10182/13887

  • Wilderness and the New Zealand mind

    “Wilderness was the basic ingredient of American culture. From the raw materials of the physical wilderness, Americans built a civilization. With the idea of wilderness they sought to give their civilization identity and meaning.” – Roderick Nash, Wilderness and the American Mind

    Since the advent of the wilderness preservation movement in nineteenth-century America, protecting wild places has meant more than simply protecting pristine ecosystems. Despite the priceless value our world’s rapidly diminishing untouched landscapes hold for biodiversity conservation, wilderness preservation has first and foremost been a cultural mission.

    Doubtful Sound, Fiordland National Park – Rod Waddington, licensed under CC BY-SA 2.0

    Roderick Nash described wilderness not as a type of ecosystem but as a “state of mind.” Investigating this mindset reveals much about our reasons for protecting nature and what nature means to our society. The people of New Zealand decided very early on that its natural landscapes were worth protecting, especially its most wild and remote places. Wilderness areas are now considered a “defining characteristic” of New Zealand, with many citizens feeling a sense of “pride” and “identity” with these wild areas.

    Wild nature, as opposed to pastoral or modified landscapes, provides many people a source of connection to the natural world that transcends typical nature amenity values. People who visit wilderness areas report experiences of the sublime, of incredible beauty, of solitude and personal growth, of the unrivalled rewards of physical challenge and overcoming risk, and of a connection with nature that is no less than spiritual. But while wild places are by definition areas with as little human modification as possible, their preservation and meaning in society are entirely human.

    University of Lincoln researcher Kerry Wray wrote their doctoral thesis on the meaning behind New Zealander’s relationship with wilderness. Kerry identified how differences in wilderness valuation say much about the country’s human-nature relationship and its internal conflicts. Wray’s thesis covers how reasons for conserving nature can come from our desire for a life of meaning and connection and how this desire can direct the course of an entire nation.

    Nations, as well as individuals, look to their landscapes for identity. Where we come from often says much about who we are. New Zealand became one of the first countries in the world to establish national parks, starting in 1892. The government enacted legislation that officially recognised national parks as “areas of New Zealand that contain scenery of such distinctive quality, ecological systems or natural features so beautiful, unique, or scientifically important that their preservation is in the national interest.” They saw them as so valuable and essential to the essence of the country’s identity that they should also be preserved in “perpetuity.”

    Statue of Sir Edmund Hillary in Mount Cook/Aoraki National Park – Geof Wilson, licensed under CC BY-NC-ND 2.0

    As the country set out to preserve its landscapes it did so in a way that reflected the collective personality of the nation’s citizens. The colonial inhabitants of this land saw themselves as pioneers and explorers. As the country transitioned from colony to statehood, it looked for ways to distinguish itself. It looked towards its unpeopled valleys, deep fjords, and soaring peaks.

    Vast swathes of wild New Zealand were and remain unlike any environment in Europe and the people that explored them saw themselves as likewise distinct. The country aimed to preserve areas for backcountry tramping and hunting, celebrating their cultural love of adventure, self-sufficiency, and exploration. And so, with a provision in the 1952 National Parks Act for remote places, the country became one of the earliest adopters of the wilderness preservation movement in the world, setting aside immense areas with policies more strict than any other country.

    There are now 6 designated wilderness areas in the country, with many more remote areas that are effectively managed as wilderness. Wilderness in New Zealand is now, mainly under the 1985 Wilderness Policy, legally considered a place undisturbed by humanity, free from infrastructure including the most basic of modifications, such as huts, bridges, signs, and even tracks.

    Wilderness preservation polices have now spread around the world, with leading international conservation organizations emphasising their immense ecological and cultural value, such as the European Commission’s issue of wilderness management guidelines, definitions, and calls for further preservation. The International Union for Conservation of Nature has created a global classification and management guidelines system for wilderness areas. There are also non-profits with storied conservation legacies, such as the Wild Foundation and Wilderness International. It was largely due to the inspired efforts of the Federated Mountain Clubs‘ love of remote back-country experiences that New Zealand wilderness now ranks among the most wild and protected in the world.

    The wilderness area of Fiordland National Park, now a World Heritage Area, is the largest and most representative of the country’s wild nature. It was here in 1773 that Captain Cook moored when plotting New Zealand on the world map. It was here in Fiordland that advancements in species conservation were made as early as the nineteenth century with the protection of entire off-shore islands and the conservation efforts of some of the world’s rarest birds, such as the kākāpō and takahē.

    In Fiordland, the ethos of wilderness preservation has led to the protection of the largest expanse of native forest in the country. For trampers, it is the most remote one can get on the mainland. However, it is also home to three of the nation’s Great Walks and a national park attracting nearly 1 million visitors a year.

    The Darran Mountains, Fiordland National Park – Dan Nelson, licensed under CC BY-NC-ND 2.0

    “Fiordland National Park represents a legacy of every New Zealander, for every park visitor; a cherished corner of the world where mountains and valleys compete with each other for room, where scale is almost beyond comprehension, rainfall is measured in metres, and scenery encompasses the broadest width of emotions. It is a place of solitude, of retreat, of quiet rejuvenation… Welcome to Fiordland, land of the last retreat” – Department of Lands & Survey 1986

    The increasing demand for access to wilderness areas and their peripheries is not only putting pressure on these fragile ecosystems but on users’ values as well. For one person, the Fiordland wilderness means the Milford Highway and they may bemoan the lack of tracks that enter into deeper sections of the park. While for others, wilderness is not reached until hiking several days away from the Park into untracked valleys and may picket propositions to improve trails and build huts. How the Crown decides to manage these conflicting user expectations can direct the course of nature conservation in New Zealand as a whole, a country with more ecotourists and backcountry users every year.

    Which values will be prioritised? What interpretation of wilderness will be used in future? And, is the idea of wilderness always appropriate? Can it be harmful?

    Sign in Kauri National Park – Eli Duke, licensed under CC BY-SA 2.0

    With over a third of the country set aside for conservation and with one of the most extensive and strictly defined wilderness preservation systems in the world, New Zealand is a model case study in the phenomenon of wilderness preservation. But it is a phenomenon that is only beginning to come to terms with its colonial heritage.

    That word, wilderness, as well as its connotation, do not translate well out its Germanic language roots. Many people and cultures around the world have differing conceptions and values of wild places. And the Europeans who pioneered the idea paid little attention to human-nature relationships already present in these allegedly pristine or “Edenic” places.

    Indigenous peoples were the first to suffer from modern conservation strategies. Not only were they displaced from their lands but their heritage and legacy were ignored or erased. For example, nearly all wilderness areas in the United States were inhabited by native peoples before being designated. The European-American cultural idea of civilization vs wild nature imposed itself atop hundreds of years of indigenous peoples’ heritage with these ‘wild’ places. Wilderness preservation has led to the degradation of global indigenous heritage and even overt oppression.

    Countries around the world are now reassessing their relationship with nature conservation, including New Zealand. The future of Fiordland National Park, with its 800-900 year history of Māori inhabitation, has complex and competing human-nature relationships to be considered. Certain conservation lands throughout the country are now being reclaimed by iwi. Concessions are being made to allow customary use of natural resources across Crown Land. Wilderness areas are now being criticised for concealing indigenous heritage and restricting rights.

    The wilderness landscape of New Zealand played a large role in the creation of a national identity and a conservation agenda post-independence. Now again the idea of wilderness will play a role in how the country decides to manage its conservation lands and for whom.

    Nature conservation in New Zealand means more than saving the endangered birds. It has to do with culture, the quest for identity and beauty, and now, also, justice. There are many definitions of wilderness but all of them speak of a place somehow both lacking in humanity and a place to be sought, a wasteland and a wellspring of emotion, somewhere unmarked by human hands yet telling of our passions.

    The road into Aoraki Mount Cook National Park – /\ltus, licensed under CC BY-NC-ND 2.0

    Kerry’s work is a landmark piece in the academic discussion of New Zealand wilderness management. The many intangible values of wilderness and its environmental justice issues make it a complex idea to study or even casually talk about. Yet, Kerry’s endeavor describes why wilderness values are so important and demonstrates that it is possible to study them and produce substantive ideas for addressing its many complex problems.

    William Cronon’s famous critique of wilderness preservation called wilderness a “monument to the nation’s past.” The mounting challenges to conservation lands press our eyes forward. How we decide to value our world’s diminishing wilderness speaks to how we will value nature all together and what the future landscape of this country will look like.

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

  • Repelling New Zealand’s deer: keeping the target on predators

    Imagine walking through the lush forests of New Zealand, where native birds sing and the ecosystem thrives. For many, the thrill of hunting deer adds to the adventure, as these animals are both prized game and an integral part of the environment. However, lurking within this paradise are predators, like possums and rats, which threaten the very fabric of this delicate ecosystem.

    To combat these problem predators, New Zealand has employed a controversial yet effective method: aerial 1080 poison drops. These toxins are effective against pests but can inadvertently harm other wildlife, including the beloved white-tailed deer (Odocoileus virginianus).

    White Tailed Buck.
    Brad Smith. July 3rd 2006

    White-tailed deer are not native to New Zealand; they were introduced for hunting in the early 20th century. Despite being an introduced species, they have established a stable population and have become an important part of New Zealand’s hunting culture, especially the population on Stewart Island. Protecting them is crucial not only for maintaining biodiversity but also for supporting the recreational and economic benefits associated with deer hunting.

    Recent studies have shed light on how we can minimise this collateral damage by using deer repellents. Let’s dive into the findings and their implications for both wildlife management and conservation.

    New Zealand’s unique biodiversity is under constant threat from invasive species. Possums, rats, and stoats prey on native birds, insects, and plants, disrupting natural ecosystems. To protect these vulnerable species, aerial drops of sodium fluoroacetate, commonly known as 1080, are used. This toxin is highly effective at reducing predator populations, but it’s not without its drawbacks. One significant concern is the unintended by-kill of non-target species, such as the white-tailed deer.

    Intensive ground-based searches for white-tailed deer carcasses were conducted in the Dart Valley/Routeburn catchments following the aerial application of 1080 cereal pellets as part of the ‘Battle for the Birds’/Tiakina Ngā Manu predator control program in August 2014. Lincoln University PhD student Kaylyn Pinney, with her supervisors James Ross and Adrian Paterson, organised this search. Four areas, each 100 hectares in size, were searched over four days. The results were published in NZ Journal of Zoology.

    To estimate the effectiveness of their search, simulated deer carcasses were used. The success rate for finding these simulated carcasses was 78%. All actual white-tailed deer carcasses found contained traces of 1080 in their muscle tissue (ranging from 0.41 to 1.06 mg/kg). Based on these findings, researchers estimated that approximately 3.85 deer per 400 hectares died from 1080 poisoning. This translates to a potential mortality of about 146 white-tailed deer across the entire 15,215-hectare predator control area. These results suggest that recurrent predator control operations could impact the sustainability of white-tailed deer hunting. (For more on this see ‘Is it fair, for orcs and deer?’)

    Repellents are substances designed to deter animals from consuming certain items without causing them harm. In the context of predator control, deer repellents can be coated on 1080 baits to reduce the likelihood of deer ingesting the poison.

    Kaylyn Pinney then tested a deer repellent-coated 1080 bait to see if it could reduce the mortality of white-tailed deer during predator control operations. She tested two types of repellents: Epro Deer Repellent (EDR) and Pestex-DR. The study was divided into two parts: trials in a captive herd on the West Coast and monitoring of wild deer fitted with GPS collars in the Dart/Routeburn Valley in Otago, New Zealand.

    Routeburn Valley.
    yiwenjiang26, Routeburn vally closer up. March 10 2007.

    In the captive trials, five deer were presented with three types of cereal baits: non-repellent (NR), EDR-coated, and Pestex-DR-coated. The baits were placed in a controlled environment where deer could freely choose among them. The results were promising. The deer showed a clear aversion to the repellent-coated baits, with significantly less consumption compared to the non-repellent baits. The repellents appeared to be effective, though not infallible. One older buck did consume a single EDR-coated bait initially but avoided it afterward.

    The second part of the study involved monitoring ten wild deer equipped with GPS collars during a 1080 drop. To fit the deer with GPS collars, Kaylyn and crew captured the animals by tranquilising them and then attached the devices. Kaylyn could now track their movements and monitor their survival. The results were mixed. One deer, the youngest in the study, died from 1080 poisoning, suggesting that body size may play a role in susceptibility to the poison. Importantly, the study confirmed, however, that using EDR significantly reduced deer mortality compared to previous operations without repellents.

    While the study shows that repellents can reduce by-kill, there are challenges. Ensuring that every bait is adequately coated with repellent is crucial. Additionally, different deer may react differently to repellents, as observed with the older buck in the captive trial. Kaylyn suggests that using a lower concentration of 1080, such as 0.08%, could further reduce deer mortality, especially for smaller deer.

    The study also highlights the importance of understanding deer habitat use. The GPS collars allowed researchers to identify how much time the deer spent in different types of habitats. The varied exposure of the collared deer to the 1080 baits was influenced by their movement patterns and habitat preferences. Future studies should consider these factors to optimise bait distribution and minimize non-target impacts.

    1080 Warning Sign.
    Shaddon Waldie, 1080. July 30th 2009.

    These findings have significant implications for wildlife management and conservation in New Zealand. By using deer repellents like EDR and Pestex-DR, we can make predator control operations more targeted and reduce the unintended consequences for non-target species. This approach not only helps protect the native ecosystem but also addresses public concerns about the humane treatment of wildlife.

    The study underscores the need for continuous innovation and adaptation in conservation strategies. As we gain more insights into the behaviour and ecology of both target and non-target species, we can develop more effective and sustainable methods to preserve New Zealand’s unique biodiversity.

    The journey to protect New Zealand’s native species is complex and challenging. This study offers a glimmer of hope by demonstrating that deer repellents can significantly reduce the by-kill of white-tailed deer during aerial 1080 operations. While not perfect, these findings pave the way for more refined and humane conservation practices. As we continue to balance the needs of predator control with the protection of non-target wildlife, studies like this guide us toward a more sustainable and harmonious coexistence with nature.

    Imagine once again walking through those lush forests, now knowing that both the native birds and the majestic deer can thrive in a balanced ecosystem.

    This article was prepared by Master of Science postgraduate student Ella Gordon as part of the ECOL608 Research Methods in Ecology course.

    Link to the main article

    Pinney, K. A., Ross, J. G., & Paterson, A. M. (2022). Assessing EDR and a novel deer repellent for reducing by-kill of white-tailed deer (Odocoileus virginianus), during aerial 1080 operations. New Zealand Journal of Zoology, 49(3), 199–214. https://doi.org/10.1080/03014223.2021.1978510

    Additional Links and Further Reading

    New Zealand Department of Conservation

    The New Zealand Department of Conservation (DOC) website provides comprehensive information about New Zealand’s natural heritage, conservation efforts, and recreational opportunities. Key sections include:

    Parks & Recreation: Information on places to visit, activities, camping, and hiking.
    Nature: Details on native plants and animals, pest management, and habitats.
    Get Involved: Volunteering, funding opportunities, and educational resources.
    Our Work: Conservation projects, research, and monitoring programs.

    Manaaki Whenua – Landcare Research

    The Manaaki Whenua – Landcare Research website provides a wide range of information on New Zealand’s land environment and biodiversity. It covers research areas such as soil health, water management, biodiversity conservation, and climate change. Additionally, it offers resources for educators, data and mapping tools, and information on various conservation projects. The site also features sections for news, events, and opportunities for public involvement in environmental efforts.

    1080: An Overview

    The “1080: An Overview” page on the Predator Free NZ Trust website provides comprehensive information about the use of 1080 (sodium fluoroacetate) in New Zealand for predator control. It details what 1080 is, why it is used, its application methods, and its effectiveness. The page also covers the benefits and risks associated with 1080, including its impact on native species, non-target species, and the environment. Additionally, it includes examples of successful 1080 applications and addresses common concerns such as its impact on drinking water.

    Nugent, G., & Yockney, I. (2004). “Feral deer in New Zealand: current status and potential management.” New Zealand Journal of Zoology.
    This article discusses the status and management of feral deer populations in New Zealand.

    Morriss, G. (2007). “Epro Deer Repellent reduces by-kill of deer during aerial 1080 operations.” Landcare Research Report.
    This report provides detailed findings on the effectiveness of EDR in reducing non-target by-kill.

    Frampton, C. M., et al. (1999). “Efficacy of 1080 carrot baits in controlling possums.” New Zealand Journal of Ecology.
    This study examines the effectiveness of 1080 in controlling possum populations.

    Spalinger, D. E., et al. (1997). “Influence of learning and experience on foraging behavior of white-tailed deer.” Journal of Wildlife Management.
    This research explores how learning and experience affect deer foraging behavior.

    Bowen, L. H., et al. (1995). “Leaching rates of 1080 from RS5 cereal baits under simulated rainfall.” New Zealand Journal of Ecology.
    This paper discusses how environmental conditions affect the concentration of 1080 in baits.

    Pinney, M., et al. (2020). “Effectiveness of deer repellents in reducing non-target by-kill during predator control operations.” Journal of Wildlife Management.
    This study delves into the specific effects of deer repellents on non-target species during 1080 operations.

  • Lonely nature: the fear of suburbia

    Blandly pleasant houses flank wide roads. Inoffensive strip gardens line dull driveways and plain, wooden slat fences. Every street is perfectly plain and welcoming. The normal neighbourhood stretches on, unchanging for blocks.

    If you have looked for a house, flat, or rental in the past fifteen years, you have visited this suburb. Welcome home.

    Does anyone else listen to the Magnus Archives? It’s a fictional horror podcast where an archivist records first hand accounts of people pursued by manifestations of their own fear, including the fear of always being watched, hunted by dark beasts, or being horribly, completely alone. The endless suburbia described above is from one of these accounts: an episode named Cul-de-sac.

    Horror employs the unknown, unnatural, and surreal to frighten its audience. I find it disconcerting that modern suburbia is considered uncomfortable enough to feature. Scarily, it works. In this particular account, the writer finds themselves alone in a desolate suburban neighbourhood, absent of life and vigour. Nothing defines one home from the next. Gardens are non-existent, and no other living thing is present. Why is this dull repetitiveness so horrifying?

    Our homes define us as much as we define them. When an area is so lacking in character, in life, it ceases to be a place at all. Global trends of urban design (especially in western countries) have spent decades prioritising vehicles over personal well-being, land-use diversity, and ecosystem health. Poor planning has resulted in biologically desolate, emotionally draining landscapes that we spend our entire lives in. Some land uses, such as industrial, are considered incompatible with nature. As a result, suburban design has an imperative theatre to reintroduce biodiversity into our every-day lives.

    “The normal just seemed to go on forever.” The Archivist, The Magnus Archives. Episode 150 “Cul-de-sac”.
    Image: Author. All rights reserved.

    In 2008, Maria Ignatieva, Glenn Stewart, and Colin Meurk published an article in the New Zealand Landscape Review titled: “Low Impact Urban Design and Development (LIUDD): Matching Urban Design and Urban Ecology.” They recognised New Zealand’s poor history in applying ecological principles to landscape design, which has led to the depreciation of native biodiversity, landscape legibility, and the tidal wave of invasive exotic organisms. Global trends, such as rewilding in the UK, nurture communities that respect, conserve, and enhance natural processes. This is not easy, as ingrained cultural perceptions of our relationship with ecology are complex. As put by Joan Nassauer in her article Messy Ecosystems, Tidy Frames:

    “People may care about improving ecological quality, but not at the expense of the proper perception of their own landscape”

    Socio-cultural norms borne from the picturesque design movement still drive perceptions of how landscapes should appear, more than 200 years after they were conceived. To see an iconic picturesque landscape, take a glance at this article on Stourhead Gardens in England. These preconceived values, lack of diversity, and cost-driven urban development result in homogenised, unlively neighbourhoods; perfect habitats for Cthulhu-esque, eldritch beings to consume lonely creatures’ fears in, but less perfect for our native flora and fauna.

    Two key methods of Low Impact Urban Design and Development were identified to address these issues: designing for sense of place (to improve public perceptions), and for native biodiversity. As an example, Ignatieva and colleagues suggest the use of ‘plant signatures’ in suburban design. These signatures are assortments of plants that provide context clues of the landscape; species are chosen deliberately to represent the ecological needs and habitat functions of that environment. This contrasts with most plant selections which are often driven by cost, function, or amenity driven calculations. Character and identity are inherent in an ecologically aware plant palette, and designers worth their salt should demonstrate this in thoughtful design choices.

    A stormwater system in Te Whāriki subdivision, Lincoln. Image: Author. All rights reserved.

    These ideas have been present for decades: plant signatures were coined by Nick Robinson in 1993, and Ignatieva and colleagues’ article was published 16 years ago. So, what effect have Low Impact Urban Design and Development and plant signatures had on increasing urban biodiversity? I met with Colin Meurk, one of the authors, to hear his thoughts. “Low Impact Urban Design and Development is pretty much history, apart from the legacy effect,” he said. “We use different jargon now.” Oh. Right.

    The thing is, just because ideas are innovative does not mean they are embraced and applied. In places, Low Impact Urban Design and Development has successfully evolved– Meurk points to stormwater design and ‘sponge cities’ as evidence that ecological concepts can assimilate successfully into current landscape practice.

    Te Whāriki in Lincoln is a great example of this: as a result of high clay soil and ground-fed springs, this subdivision needs to detain high levels of stormwater. The standard method to do so is with large grass-mown basins, such as those seen down the road in Wigram. Instead, Te Whāriki is designed with extensive wetland systems that support a wide range of native plants, bird species, and invertebrates. The wetlands also provide excellent public spaces, with walking tracks, seating, and street-inter-connectivity. My own parents chose Te Whāriki as their new home in 2022 specifically for the wetlands!

    A path through a stormwater system in Te Whāriki subdivision, Lincoln. Image: Adrian Paterson.

    Yet, ecological principles within suburban design are the exception rather than the rule. Is this because ecological action is still viewed in opposition of cultural values, as Nassauer would suggest? Is it that policy makers do not sufficiently emphasise ecological principles, or because developers dislike the financial ‘deadweight’ of ecological oriented design?

    I would suggest all three, although there is greater nuance and complexity than I have room to explore here. Notably, Te Whāriki was developed by Ngāi Tahu in conjunction with Lincoln University, both parties whom have a vested interest in increasing biodiversity in the region.

    It is disquieting that a common expression of modern living is easily utilised as a metaphor for horror and loneliness. What does it say about modern design that it can easily parallel horror and fear? When we met, Colin Meurk labelled modern subdivisions as an ‘extinction of experience’.

    Younger generations are often criticised for spending too much time on technology, but when they live in lonely neighbourhoods, can we blame them? In failing to design for biodiversity, we rob ourselves of opportunities to experience the natural world. Low Impact Urban Design and Development may have been subsumed into other concepts, but designing in a manner conducive to the natural world and people is more relevant than ever. Plant signatures are an excellent method to incorporate biodiversity and character in our suburbs. Birds, invertebrates, reptiles – they would love to take part in our neighbourhoods, and I, for one, would prefer a lively neighbourhood over a horrifying, lonely suburbia.

    Life provides. Image: Author. All rights reserved.

    This article was prepared by Master of Science postgraduate student Nathan Campbell as part of the ECOL608 Research Methods in Ecology course.

    Reference Article: Ignatieva, M., Meurk, C. D., & Stewart, G. H. (2008). Low impact urban design and development (LIUDD) : matching urban design and urban ecology. Landscape Review 12(2):61-73.