In New Zealand, many would agree that fresh water is one of our most loved natural resources. We drink it, we swim in it, we use it to farm and to make a living, we even use it to generate our power! Unfortunately, especially in Canterbury after some major earthquakes, many of our streams and rivers are struggling. They look something like this:
Kowhai River, Kaikōura. From Environment Canterbury, ND.
In stream restoration, we want to return the features of a stream back to their original state, before things like urban development or introduced species affected the quality. This includes adding native plants, allowing fish to make their way out to sea or further upstream, and making sure farm animals can’t walk straight into the stream. All of these things and more can help us to make healthier waterways.
It does not always go to plan, with some hardy introduced species putting a spanner in the works and refusing to co-operate with careful scientific methods. Imagine a beautiful stream that’s been through tough times—pollution, habitat destruction, earthquakes you name it. People step in – scientists, council members, developers, maybe the general public, and they work hard to restore it, but here’s the kicker: sometimes, things just don’t bounce back like they should. Why? That’s exactly what a recent study by Issie Barrett and her team set out to uncover.
To understand why streams struggle to recover even after the most thorough restoration efforts, we need to understand a few key factors.
1. Species Interactions: In a healthy stream, different plants and animals interact in specific ways, such as some animals eating others or different plants competing for space. When a stream is damaged and then restored, these interactions might not work the same way anymore. This can make it harder for the original species to come back and thrive.
A particular species of snail, the New Zealand mud snail (P. antipodarum) is particularly good at living in these degraded streams, they thrive under pressure and limited food sources. These snails are perfect species to take over a degraded environment and reduce the recovery ability! So even when original species are introduced, such as the mayfly, the same food source now has double the competition, meaning a negative reaction – that habitat can’t provide that much food even in a restored state.
New Zealand mud snail Potamopyrgus antipodarum. Photo Credit Michal Maňas 2014
2. Negative Resistance: This is a big concept, which in essence means that even when the physical conditions of a stream improve (like cleaning up pollution or adding new habitats), the plants and animals in the stream don’t always come back as quickly or fully as hoped.
During the stream’s degradation years, new species like the mud snails might move in – kind of like uninvited guests crashing a party. Even after things are cleaned up, these newbies can stick around and hog resources, making it harder for the original gang to make a comeback. This is what they call “negative resistance.” This can happen because the habitat is too degraded for the ideal species to thrive even if they did before.
3. Resilience Mechanisms: This means the ability of a system to absorb and adapt to change, ultimately returning to the restored ideal. This is where our negative resistance comes into play. If the species or the system is already not functioning as it should, we are going to have a hard time creating a resilient system that can adapt to a changing environment and overcome any future issues.
For example, a high level of nitrogen could change the make-up of the riverbed so drastically that a species sensitive to nitrates may never repopulate that system. Understanding the relationship between negative resistance and resilience is important for predicting and enhancing any successful restoration efforts.
What can we do?
Look at the Big Picture: When restoring a stream, it’s not just about fixing what we can see. We need to think about how all the different plants and animals interact with each other. This includes what nutrients are in the water and what microscopic invertebrates might be living in that water.
Keep Checking In: It’s important to keep watching restored streams over time to make sure they’re getting better and to fix any problems that come up. If we don’t see an improvement in 5 or 10 years, there must be something else we can do.
Be Flexible: Sometimes, we might need to change our restoration plans based on what we learn from watching how the stream responds. As scientists we have to be okay with admitting our first idea didn’t work, and then be willing to help come up with a better solution for the future.
Vegetated drain in Canterbury with optimum riparian planting. Photo credit Jon Sullivan, ND.
Why it matters
Overall, there are some pretty complex systems that are at play in stream restoration projects. It is not as simple as putting in some better plants and some bigger, cooler rocks and hoping it will all work out in 10 years. By paying attention to how plants, animals, and the environment all work together, perhaps we can work towards a deeper understanding of the best ways to help our New Zealand streams thrive for many more generations to come.
I think it would be pretty cool to keep swimming in our rivers and looking for fish in the summer, but next time you go to your local river, have a look and see what plants and other animals would really love to keep living there too.
Researchers compared two populations of kakaruai/South Island robins in similar forest habitats, one from the predator free island of Motuara and one from the main island, where introduced predators are present.
In the experiment, robins from the main island were more shy and less bold when they could pick up presented food items close to the researchers.
This suggests that a selection pressure from introduced predators favours individuals that are less bold and more cautious, potentially shifting personality traits of individuals in populations under predation pressure in the long term.
Petroica australis in the Hawdon Valley (Arthur’s Pass). (C) Copyright Maximilian Hanschmann – all rights reserved.
The small birds only weigh 35g and can survive up to 17 years – given that they are safe from invasive predators.
While still occurring on the main islands and doing better than many other species endemic to New Zealand, that evolved in the absence of any mammalian predators, the robins struggle to survive since several predatory mammal species have been introduced to New Zealand by humans.
During their evolutionary history in New Zealand, the birds never needed to coexist with these predators and as such act in a naive way towards them, making them an easy prey for ship rats, possums, stoats, weasels and feral cats.
Introduced predators are a big problem for robins, even if populations survived until now, they are struggling where predators are present, a fate they share with almost all remaining native bird species. Predators will prey on eggs, nestlings, fledglings and adult females in the nest, leading to skewed sex ratios, where there are many more males than females in the population. The risk of nest predation is seven times higher where mammalian predators are present, and the life expectancy of adult birds is reduced by roughly 75% compared with areas free of predatory mammals.
Petroica australis on the West Coast of South Island. (C) Copyright Maximilian Hanschmann – all rights reserved.
Individuals in two different populations, living in a similar native (kanuka Kunzea ericoides dominated) forest habitat but with a different exposure to introduced mammalian predators, were studied. One population lives on the predator free island sanctuary of Motuara and originates from a population that was never under the influence of mammalian predators, except for rats. The other population lives in two connected patches on mainland New Zealand, close to Kaikoura and is exposed to mammalian predators present at the site, including feral cats, stoats, ferrets, weasels, rats, mice and possums.
The aim was to assess the boldness of the robins or the willingness to take risks, which can vary among individuals within a species and can be influenced by environmental factors.
A robin in Nina Valley. Image from Adrian Paterson
To assess the propensity to take risks (known as the ‘shyness-boldness’ continuum) of the birds, mealworms were presented as food items at different distances to the researchers (proximity as a risk). It was then noted how long a bird took to pick the first item up (approach time) and how long a bird took to pick up all the food items (handling time). The quicker the bird approached and the more time it spent close to humans, the bolder it was considered.
The results showed that robins not under influence of predators had a significantly bolder personality. They were much more likely to quickly come as close as 30cm to the researchers and spent more time handling the food as robins that live on the mainland, under the predation pressure of various introduced mammals.
The findings highlight the big impact of introduced predators, influencing the behaviour and possibly evolutionary outcomes. Individuals that are more cautious around predators are less likely to get killed and have a greater chance to have more offspring, promoting their personality traits in the next generations. These effects are likely not limited to robins, but likely also apply to other struggling native bird species that survived until now.
Robin and trail camera in Nina Valley. Image from Adrian Paterson.
What you can do:
Spread the word! Talk with other people about biodiversity issues and how to solve them.
Value the unique native ecosystem of New Zealand and its vulnerable species.
Promote no-go areas where birds breed and in core areas of vulnerable ecosystems.
Lobby for better regulations and environmental standards.
Use your vote in elections to support the effort to safe New Zealand’s unique, but highly endangered biodiversity.
Control predators on your property. Help others controlling predators.
Plant native plants from your region. Remove non-native plants, even if they are “pretty”.
Participate in citizen science (e.g. iNaturalist) and help to detect various species.
Be a responsible cat owner: cats should be microchipped, registered and unable to reproduce uncontrolled. Consider walking your cat on a leash or ensure it can’t leave your property. New Zealand’s native species are exceptionally vulnerable to predation! Feral populations are not only a huge issue for non-adapted, vulnerable species, but also an animal welfare problem for the feral cats.
Be a responsible dog owner: dogs should be microchipped, registered and unable to reproduce uncontrolled. Walking your dog on a leash reduces the negative impact on wildlife. Dogs are among the gravest threats for adult kiwi, as they can kill a kiwi by just giving it a playful push (kiwis don’t have a sternum and are incredibly vulnerable). Ensure the dog can’t leave your presence.
Read the full study here: White, R., Rossignaud, L., & Briskie, J. V. (2023). The bold bird gets the worm? Behavioural differences of South Island robins (Petroica australis) in relation to differing predation risk. New Zealand Journal of Zoology, 51(2), 334–349. https://doi.org/10.1080/03014223.2023.2255165
As a kid I explored the waters of the Marlborough Sounds. I caught my first fish there at seven years old and, one New Year’s day, my biggest snapper weighing about 25 pounds. I have been awed by watching fish and bird feeding frenzies- the food chain in practice. I learnt to dive off boats in emerald waters and spent many evenings watching the sunset and roasting s’mores at an isolated and tranquil DOC campsite. A place we call our “bach”.
But I have never seen a Southern Right Whale, nor an Elephant Seal, or a Waitaha Penguin, in the Marlborough Sounds. Prior to my childhood it was a different Marlborough Sounds. Stephen Urlich and Sean Handley delve into the historical changes of this beautiful location, exploring how food webs have been disrupted since human settlement. The aim of the study was to address knowledge gaps by taking an integrated approach to examining how land use has impacted on coastal ecosystems.
Stephen and Sean focused on keystone species. They traced the history of whaling in Port Underwood, within the Sounds. When John Guard’s first whaling ship entered the harbour in 1828, whales were abundant. Sadly, by 1836, there were 18 vessels sending out 70 whaling boats to chase these majestic creatures. Whaling led to a significant transformation of the Sounds’ ecosystem.
Image by Author- Out in the Sounds
Keystone species, like the Southern Right Whale, play a crucial role in transferring energy within the coastal food web. Their role as ecosystem engineers, essential for habitat formation, was lost by human greed. Sadly, as the authors remind us, the Southern Right Whale was not the first animal hunted by humans in the Sounds. During Maori colonisation, the Elephant Seal, New Zealand Fur Seal, New Zealand Sea Lion, and Waitaha Penguin were all harvested. Hunting led to the decline of the Fur Seal population and the local extinction of the Sea Lion, Elephant Seal, and the Waitaha Penguin.
What is happening to our waterways? Who is responsible for the ongoing transformation of precious natural environments? Us. Once the habitats of the Marlborough Sounds flourished. The study highlights that in the past, there were various subtidal habitats formed by species such as giant kelp forests, as well as communities of hydroids and sponges. As early as 1863 there was dredging for oysters in the Tory Channel and trawling began in 1904. Both of these disturbed the habitat and permanently changed the landscape. Since the 1970s, commercial enterprises of dredging for subtidal green-lipped mussels has been destroying these habitats.
The destruction has continued into my lifetime. For example, in the dramatic 2021 floods , my friends bach slid down a hill. A shocking destruction of a home filled with memories. But the hidden impact of mud slides is far more devastating. Mudslides cause excessive amounts of brown sediment to be displaced from the land, settling in the Sounds and leading to extensive physical disturbance to vulnerable habitats.
Image by Author- Commercial Mussels Farms
But why so brown? Once Europeans arrived the Sounds continued to change. By the 1970s pine plantations had become widespread and clear felling had begun. Harvested and existing forest makes up about 18% of the land surface in the Marlborough Sounds but contributes to around 65% of landslides in 2021 and 2022 (Hart, 2023). Over the last 50 years sediment accumulation rates skyrocketed and continue to remain elevated. This is seen clearly in the Havelock estuary, which increased soft mud habitat by 34 ha from 2001 to 2014. Steep indigenous forested areas also receive this rainfall but are unrepresented in the slip data.
The idea of ecosystem-based management (EBM) is also promoted by Urlich and Handley as a way of improving the catchment management. The suggested aim for Marlborough Sounds would be to restore ecological functions so that biodiversity can be maintained. Marine protection is an important part of EBM in New Zealand. It helps to protect remaining high quality habitat and can help with the recovery of more diverse habitats. With proper management maybe one day we will be able to see the return of more mussel beds and marine mammals.
Is New Zealand really ‘Clean and Green’? Maybe on the surface. But what is happening to habitats in places like the tranquil depths of the Marlborough Sounds? The factors impacting marine habitats are often not well understood. Urlich and Handley suggest that the Marlborough Sounds could rather be referred to ‘brown and down’. This is partially due to the fragmented nature of marine management, where various institutions operate at different scales under diverse legislation.
Image by Author – My campsite “bach”
Urlich and Handley highlight that the current marine protection of the Sounds is inadequate as there is only one fully protected reserve. The management of habitats outside this reserve has become an ongoing legal issue. Since the 1880s, calls for additional marine protection within the Sounds has been disregarded. Conservation effort in the Marlborough Sounds is extremely challenging. This study highlights the urgent need for transformative changes in the Marlborough Sounds. It is suggested that the EBM needs to focus on managing seabed disturbance, reducing sedimentation and including Matauranga Maori ecosystem-based management. The EBM has the opportunity to change the narrative back to clean and green from ‘brown and down’ by providing innovative management (Urlich & Handley, 2020).
Now, when I go out in the Marlborough Sounds, where I was once catching multiple snapper, I am now spending days catching absolutely nothing. With hindsight I need to ask myself: was I part of the problem? Recreational overfishing has contributed to a decline in species.
Additionally, where once I was surrounded by deep blue sea, now it is often a murky mix. It is time for Marlburians, and New Zealanders as a whole, to take responsibility. We don’t want a collapsing, deteriorating ecosystem. We want an ecosystem that thrives. We want to restore ecological resilience. We want generations to come and sit on remote beaches in the Sounds, benefiting from a thriving ecosystem.
This article was prepared by Applied Science Postgraduate Diploma student Hannah Smit as part of the ECOL608 Research Methods Class.
Urlich. S.C., Handley. S.J. (2020). From ‘Clean and Green’ to ‘Brown and Down’: A synthesis of historical changes to biodiversity and marine ecosystems in the Marlborough Sounds New Zealand. Ocean and Coastal Management. https://www.sciencedirect.com/science/article/pii/S0964569120302593
“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.
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.
High in the treetops of a lush forest, a group of native birds gathered together, their vibrant feathers glinting in the dappled sunlight. Excited chirps and melodic trills filled the air as they engaged in a lively conversation. Their voices carried the hopes and dreams of a restored ecosystem.
Koru, a charismatic Tūī with iridescent feathers, fluttered his wings and cleared his throat. “Have you all heard the latest? The Humans are determined to make New Zealand predator-free by 2050!”
The cheeky Kākāriki, a lively parakeet, interjected. “Can we truly reclaim our forests from the claws and jaws of those invaders?” A wise and observant Morepork owl, Ruru blinked his large, round eyes. “Is that so? Quite a lofty goal, but can they really do it?”
Red-crowned Kakariki, Photo credit: CC BY-NC-ND 2.0 Simeon W, Flickr
With its unique biodiversity, New Zealand is home to a huge array of species found nowhere else on Earth. However, many of these treasures face an existential threat from invasive predatory mammals, such as rats, stoats, and possums, introduced by human settlers centuries ago. These voracious predators ravage the native bird populations. Many species are now extinct, and more are now on the brink of extinction.
Predator-Free New Zealand 2050 (PFNZ2050) was initiated in 2016 with an audacious aim of eradicating the most destructive trio of predators: possums, stoats, and rats; from New Zealand. This call for action echoed through the mountains and valleys, inspiring conservationists to make New Zealand, once again, a land of breathtaking beauty and thriving unique biodiversity. The ambitious aim of Predator Free 2050 is not without precedent. To date, New Zealand has successfully eradicated invasive mammals from 105 (admittedly much smaller) islands.
The first step, removing predators with aerial 1080 poisoning and ground-based resetting traps, will help remove the majority of predators. A modified aerial 1080 approach, developed by Zero Invasive Predators (ZIP), can result in localised eradication. This was first tried in a 400-ha area at Mt. Taranaki in 2016, then at a 2,300-ha site in South Westland, using ground-based resetting traps. Regular servicing of resetting traps also gives better ground-based control results.
Once pests have been eradicated from an area, the next big challenge is to defend the area from invasion. ZIP demonstrated how to defend predators from re-invasion in two sites using a “virtual barrier” of traps. A 2 km wide barrier of traps protected a 400-ha peninsula at Bottle Rock in the Marlborough Sounds. Using this virtual barrier of traps, ZIP prevented predators from re-invading at two sites, in the short term.
Australian brushtail possums, initially introduced into New Zealand for the fur trade, and now one of the major pest mammals in New Zealand. Photo credit: CC BY-SA 2.0, Gnu Chris, Flickr
Detecting the survivors is the next crucial phase for eradication, as any survivors can build a new population. The CWMC and Cacophony Project found that thermal cameras are 3.6 times more sensitive than trial cameras in detecting possums. Whilst trail cameras appear to improve detection rates, they do not always trigger when a small, fast-moving animal moves in front of them. These cameras also use infrared illumination at night, which may deter some animals.
Thermal cameras are a new advanced technology that shows high sensitivity in detecting both small and large pest mammals. Because the motion detection is done using software, the sensitivity can easily be adjusted. Unlike trail cameras, thermal cameras do not require infrared illumination to operate at night.
Videos collected by the thermal cameras are classified using AI technology (machine learning) trained on a library with more than 50,000 tagged videos. The AI can identify the animal species and only keep recordings for the target pests, which can be stored on-board the device or sent out using the cellular network.
To achieve the PFNZ 2050 goal, detecting the last few individual pest mammals is complex and expensive. As a technical improvement in detection, ZIP has made an AI network of over 500 cameras across the Predator-free South Westland project area. The AI cameras use LoRa (low-powered radio technology) to send the information to solar-powered mini-satellites. The information is transferred to a web server that checks the information the next day. The AI cameras only need to be serviced twice a year to change the batteries. The AI cameras have reduced the time to detect one predator from around six weeks to just one day and have reduced the cost significantly.
PFNZ2050 will require more innovative strategies, control tools, and wider public support to be successful in its ambitious challenge. Future control work will increasingly take place in and around urban areas. As such, the next most important advancement needs to be construct control tools that community groups can use. There should be a bottom-up-driven approach to community engagement in conservation so that as new technologies become available, the number and size of invasive mammal-free publicly and privately managed reserves can increase. In a recent study, people showed high support for species-specific toxins, but there is a shortage of funding for registration of these toxins.
NZ has a 60-year history of eradicating pest mammals, from tiny 1-ha Maria Island to more than 11,000 ha Campbell Island, with suitable techniques and public support. This is an example of how the impossible becomes possible when passion, science, and community unite.
With a final chorus of their harmonious calls, the native birds took flight, their wings carrying their hopes and aspirations to the corners of the land. From forests to cities, their songs echoed, touching the hearts of all who listened.
This article was prepared by postgraduate student Mohamed Safeer as part of the ECOL 608 Research Methods in Ecology course for his Master of Pest Management degree.
Imagine the Canterbury Plains blanketed in tall trees interwoven with small hardwoods. This beautiful, unique landscape is then singed into dry grassland with the arrival of Māori. Continue to imagine European settlers introduce weedy exotics that infest the landscapes, once again modifying the region. Now, picture the current landscape – a monotonous cover of dairy farms. Which of these images would you think is best for our native and endemic species?
Prior to humans or today? (Think from an insect’s perspective)
The plains have been a dynamic landscape ever since humans stepped foot in our vulnerable country. They will continue to experience dramatic changes in the future with the ever growing population leading to climate change, urban expansion and agriculture intensification.
The 1940s saw the commencement of irrigation on the plains so that farmers could have a reliable water source to enhance the production of pasture and crops. Water facilitated the development of dairying from sheep farming, into the landscape we see today. Between 2002 and 2012, the Canterbury herd increased by 115%, accounting for 13.5% of the Aotearoa dairy herd.
These drastic landscape changes have been detrimental to many of our precious native species by creating unfavourable conditions and habitats, species such as the bellbird (Anthornis melanura) have suffered. Some species, such as paradise shelducks (Tadorna variegata), have exploded in population numbers due to the favorable wet conditions caused from irrigating.
Within the Canterbury Plains, less than 0.5% of this area is still the original remnant forest. Canterbury has been described as the most biological deprived and most modified environment in Aotearoa due to the intensification of agriculture. However, agriculture is a big portion of the country’s economy, bringing in approximately $10.6 billion (5%) of the country’s Gross Domestic Product (GDP).
The food and fiber sector are major employer, providing jobs to over 359,000 people. Not only does it feed New Zealanders, it is also a big player in the global food market. in order to come to terms with this environmental dilemma, farms need to incorporate more sustainable agricultural practices, to feed the world and to support biodiversity. Currently through education and awareness this is already becoming a point of discussion.
There has been a push to introduce native vegetation into farming systems. Several studies have examined the impacts of intensive dairy farming on soil health, vegetation, and life below ground. Farmers are now starting to see the benefits of even simple things, such as planting native vegetation. Such plantings not only positively impact farms, but also our are good for our native species, from small bugs to cryptic skinks and chatty birds.
Mike Bowie from Lincoln University, like me, grew up on a family farm, and went on to tertiary education in ecology. This brings a helpful perspective to topics around the interaction of agriculture and ecology. It led Bowie to check out the biodiversity in the Bankside dryland remnant that is surrounded by an intensive dairy farming landscape. The Bankside Scientific Reserve in a 2.6-hectare area established in 1969. Mike wanted to know how adjacent agricultural land impacts the soil composition and fauna in this reserve area.
Aerial photograph of the Bankside Scientific Reserve with kānuka and matagouri dotted throughout. (From Bowie et al., 2015)
In 1970, an initial vegetation survey was conducted by Molloy within the new reserve. Bowie’s survey in 2015 found that only 31% of plants that Molloy surveyed still remained and that 27 new exotic species were present. The fauna found in the remnant were different to that of the neighbouring agricultural land. Bowie discovered the presence of four native earthworm species along with six exotic species. The number of the exotic worm species decreased with distance into the reserve.
Bowie and his fellow researchers found 112 specimens of invertebrates, including many beetles as well as a significant native species, the ground weta! Soil pH, nitrate, and phosphate levels were all lower in the reserve compared to the surrounding paddocks.
These observations highlight the need to retain existing dryland remnants and to establish other reserves throughout the plains. A diverse landscape will support a diverse range of species. I think farmers and the community are now starting to see the value of incorporating native vegetation and agroecological principles into their system, such as mixed species pasture systems.
We don’t all need to put three hectares away into a reserve. Even small steps, such as planting a row of diverse natives along a fence line or waterway, will make a huge difference, if many farms join in.
One thing that is highlighted in this study is the need for continued maintenance of restoration and remnant projects. It is not a plant and leave situation (no pun was intended…). Weed and pest control should be continually applied in these areas to prevent exotic weeds and animals from becoming established and smothering and displacing the natives.
An example of this is in practice Te Ara Kakariki group that is establishing green dots (tiny native areas) from the Southern Alps to Lake Ellesmere/Te Waihora on private properties. This increases the connectivity of native planting, further increasing the power that these small areas can make overall. Animals and invertebrates will be able to spread throughout these dots and over the region.
Farming has transformed the landscape of the Canterbury Plains. Image from Adrian Paterson.
Farmers are becoming more aware of sustainable principles through education from organisations such as Te Ara Kakariki, DairyNZ, Landcare trust, and councils. Through education, ecology is becoming more interwoven into their practices. It will be a trick balancing the need for feeding the world and protecting the environment. Ecology is an excellent way to find this balance in agriculture, it can be adapted to any farming system to suit their needs and desires.
Mike wants to help bridge this gap, not only in this study, but also others that he has conducted throughout his time at Lincoln University. Mike has examined how native plantings encourage native and beneficial invertebrates on Canterbury dairy farms, plus many more. I too believe that ecology and agriculture can work together to create a more sustainable agriculture sector that can efficiently produce food and improve food security, whilst supporting the health of the soil, water and biodiversity.
This article was prepared by Master of Science postgraduate student Sam Fitzgerald as part of her ECOL608 Research Methods in Ecology course.
“Captain, we’re losing ground! The phosphate is encroaching.”
“Retreat to higher ground! It’s safer up there.”
“Send in the spiders and beetles! Earthworms, you stay here.”
“Defend the Buffer!!!” [insert battle cry]
If the plants and insects at Bankside Scientific Reserve could talk, they would probably sound something like that. While this 2.6 ha protected area is home to important communities of native species, it is under threat of phosphate intrusion and the breaking-up of the local habitat. Humans have greatly altered the lowland Canterbury Plains of Aotearoa/New Zealand. With the recent switch to irrigated dairy farming, very few patches of undisturbed native dryland vegetation are left in the region. This change in land-use has led to a higher reliance on fertilizers as well as water for irrigation, which has come with its own set of challenges.
Aggressive introduced weeds, pasture grasses and forbs, have also begun to dramatically alter the functioning of native plant communities. Remnant areas are both vulnerable and essential to maintaining native ecosystems (hence the need to defend the buffer). Mike Bowie and his team investigated one of these remnant areas, looking at soil chemistry, plant distribution, and soil invertebrates along transects at the Bankside Scientific Reserve. Their study identified the current conservation value of the reserve, assessed how persistence of native biodiversity changed along the pasture-reserve gradient, and evaluated the effects of the likely infringement of irrigation water and nutrients from adjacent farmland.
The vegetation of Bankside Scientific Reserve had been studied previously by Malloy (1970), who provided a detailed catalogue of the flora, listing 66 native vascular plant species. Jenson & Shanks (2005 – unpublished DOC Report) also completed a one-day reassessment of the site, but recorded only 14 native species. Today, the vegetation at the reserve can be described as a patchwork of native woody shrubs, made up mainly of makahikatoa, matagouri, and dry grassland. As Mike and his team point out, the modified soil conditions seem to have made the reserve not as well suited for native species, and better for the invasion by exotic plants. Compared with detailed surveys prior to the dairy conversion, only 31% of the original 65 native vascular plant species were found in the current study, and 27 new exotic species had arrived since the original survey.
As for the underground conditions, soil nutrient concentrations and pH were lower in the reserve than in the surrounding farmland, with peaks of nitrate and ammonium being recorded at the boundary. Meanwhile, soil phosphate was higher in lower-lying areas within the reserve. Four species of endemic (Megasolecidae) earthworms were found in the reserve, but not in the neighbouring pasture.
Other cool finds included ground wētā (Hemiandrus sp.) and trap door spider (Cantuaria dendyi). A 2011 survey by Emberson et al. (2011) also found the large rare rove beetle, Hadrotes wakefieldi, and several species of long-horn beetles. As opposed to the earthworms, the diversity and abundance of beetles and spiders in the reserve was similar to that recorded at least 10 m into surrounding farmland.
Another interesting take-away from this research, is the importance of areas of higher elevation. Although elevational differences between highest and lowest contours were <5 m in the study, the higher areas were very important in avoiding environmental change from agricultural drainage and effluents. They helped to maintain environmental conditions that were closest to the original habitat, providing the best-suited habitat for native plants and animals.
Image created by Catherine Priemer
The work of Mike Bowie and his team, along with previous studies, points out the significance of small remnant reserves for the conservation of indigenous invertebrates found in these rare dryland ecosystems. Their findings also suggest that lime and phosphate fertilisers may represent the main threats to dryland nature reserves in irrigated dairy landscapes. Above all, their research underlines the importance of the soil environment in sustaining the variety of plant, animal, and insect life in this unique environment.
Taking the team’s findings into consideration, the maintenance of a buffer zone – a protected zone established around sensitive or critical areas – could be beneficial in lessening the impacts of human activity and land disturbance around remnants, such as Bankside Scientific Reserve. To do this, native species can be planted between agricultural and conservation areas, to help protect sensitive habitat. The key take-away: Defend the Buffer!
Picture this: you’re on a camping trip, enjoying the breathtaking view of one of the most beautiful lakes of Aotearoa New Zealand surrounded by snow-capped mountains, watching the incredible red colours of the sunrise, when suddenly a ghastly smell permeates the air. You quickly discover the source – a full wastewater tank in your camping van that urgently needs to be emptied.
My friend Julia as she is emptying out the wastewater tanks of her van. Photo by Flora Brumen
For those who have not experienced the dreadful smell of such a full wastewater tank, know that this is not easily forgotten. Standing in line at a dumping station, waiting to take your turn to get rid of your own disgusting fluids while someone is emptying their toilet container right in front of you, is a situation that brings shared discomfort to campers.
Now, I may be exaggerating a little now, but you understand my point. Toilet tanks include so many chemicals, that it actually smells better than the tanks that collect just the wastewater from doing the dishes. However, it’s an experience that highlights the less glamorous side of camping but still unites people in their shared discomfort. It reminds us that wastewater is an unavoidable reality that affects us all, every day, not just while camping.
The impact of wastewater goes beyond our noses. Uncontrolled discharge of wastewater poses a threat to human health, native freshwater species and ecosystems. In New Zealand, treated wastewater is often released into waterways or the ocean. Unfortunately, this can contaminate recreational surface waters with harmful bacteria and viruses.
The consequences of this pollution are significant. Many popular swimming spots in Canterbury have been ranked unsuitable for swimming due to high levels of bacteria from human sewage found in the water. Last summer, heavy rainfall events worsened the situation, leading to increased runoff of faecal pathogens. Besides creating severe threats to human health and creating unsuitable recreational areas, the pollution also harms freshwater species and degrades aquatic ecosystems. In fact, a devastating 76% of the indigenous freshwater fish species are endangered or threatened, 46% of all lakes have poor water quality and 45% of New Zealand’s rivers are not suitable for swimming activities.
What if we could turn the tables and use wastewater to actually help save our ecosystems? That’s exactly what a recent study under the direction of Alexandra Meister, a bio-waste scientist from ESR and the University of Canterbury, in collaboration with the Christchurch City Council and Lincoln University, suggests.
The researchers carried out an experiment on Banks Peninsula, where they irrigated a site with native plant species with treated wastewater from the local treatment plant for three years. The research team made an exciting discovery: the native plants experienced significant growth with this wastewater regime. In fact, their plant height increased by an impressive 10% compared to plants not irrigated with treated wastewater.
Site of the field experiment on Banks Peninsula, that was irrigated with treated wastewater. Photo by Meister, Gutierrez-Gines, Robinson (Kiwiscience)
It doesn’t stop there. The soil at the experimental site showed no signs of an increase of potentially harmful elements – beyond what is normal in the soil – that could endanger humans or the environment. There may be exciting possibilities for combining restoration projects with wastewater application to land. By doing so, we could decrease the discharge of wastewater into our water bodies, but also promote the growth of native vegetation, leading to a potential recovery of native biodiversity.
Of course, establishing native plants in these environments can be challenging if the species are not adapted to highly fertile soil conditions that are created by treated wastewater irrigation. One particular native plant, Mānuka(Leptospermum scoparium), was an obvious candidate for this experiment. This species has the ability to eliminate harmful soil pathogens and reduce the amount of nitrate leaking into water. Even though mānuka is not adapted to such nutrient-rich conditions, typically growing in low-fertility soils instead, the species responded well to irrigation and increased their growth.
The success and safety of applying treated municipal wastewater to the land depend on two key factors: the quality of the wastewater and the characteristics of the local environment. Due to these unique considerations, it is crucial that each system is designed to specifically address these factors.
Going forward, the researchers will continue their investigation by exploring various plants and soil types. They will continue to explore different plants and soil types, expanding our understanding of where and how wastewater irrigation can be utilised effectively.
It’s time to shift our perception of wastewater. Instead of viewing it as something unseemly to get rid of, we need to recognize it as a valuable resource that can be multi-purposes. By finding innovative applications for treated wastewater, we can decrease its careless discharge and contribute to saving our environment and ecosystems.
The success of using treated municipal wastewater as a valuable resource shows us how even the unpleasant smelling wastewater from our camper van adventures something associated with an unpleasant smell can turn into the sweet scent of environmental protection and restoration efforts.
In my home country, Germany, we have cut down every bit of primeval forest. We hunted aurochs, brown bears, wolves, lynx and even beavers to extinction between the 17th and 19th centuries. After messing it all up like that, we now dare to tell other countries, that still hold on to their forests and wildlife, what to do with their nature.
“Don’t hunt those animals you used to hunt sustainably for centuries; we think they are so charismatic”. Currently, wolves are slowly coming back to Germany, and immediately people (successfully) changed laws to permit their shooting if they prey on sheep because it is “not bearable” to live in close coexistence with wild animals like that. Apparently, wolves don’t belong to Germany anymore because…yeah, because what? Because humans live here?
Now close your eyes and imagine you are a subsistence farmer. Oops, don’t close them, rather, continue reading! You can still imagine, though! Every day you’re working hard taking care of all the veggies and crops you planted to feed your family. One day you look up, and what you see is a massive giant, almost as tall as your house. That giant has destroyed everything you ever planted.
This perception of wild Africa has influenced our approach to mitigating HEI. A common attempt is to build physical barriers, such as fences, to separate humans and elephants, believing they could protect both parties. However, elephants are unbelievably strong and intelligent creatures, and they easily overcome these obstacles, leaving farmers caught in a perpetual battle to safeguard their livelihoods.
I have personally witnessed elephants knocking over trees onto “elephant-proof” electric fences to get to the other side. No fence can hold back a herd of determined elephants. Fences, therefore, cannot be the only solution when both humans and elephants need to get their food from the same land. It doesn’t stop with crop and infrastructure damage, though; Humans and elephants die through HEI. Elephants are killing around 500 humans per year and humans return the favour.
After bothering you with way too much bad news, at least I can tell you that science offers a glimmer of hope! Picture a team of brilliant minds huddled around computer screens, armed with data and determination. With powerful tools with mystical names like Agent-based modelling (ABM) and Geographic Information Systems (GIS), ecologists are unravelling the complexities of HEI to help us understand human-elephant interactions better. With these tools, the researchers can simulate scenarios and explore the factors determining conflict incidents, to develop effective measures to reduce the conflicts and to mitigate poaching. The models are needed because, due to plenty of ethical problems, these kinds of experiments could not be conducted in real life.
In their study from 2021, Abel Mamboleo, Crile Doscher, and Adrian Paterson, from Lincoln University, simulated 18 scenarios, considering things like human population, elephant population, rivers, conservation corridors, and protected areas. They evaluated their impact on different HEI incidents, such as crop damage, human deaths, elephant deaths, and hidden impacts. The term “hidden impacts” refers to indirect consequences of HEI and includes fear restricting movements, missing school, or resulting health issues. For example, their “elephant-effects scenario (ES)” evaluated the effects of varying elephant populations on HEI, the “human-effects scenario (HES)” evaluated the effects of varying human populations on HEI, and the “environment-effects scenario” evaluated the effect of varying environmental parameters (distances to rivers, protected areas and corridors) on HEI.
Using their models, the scientists identified hidden impacts of HEI (e.g. fear and resulting health issues or restricted movements depending on elephants) as the most challenging incidents to mitigate. Interestingly, maintaining a greater distance from rivers seemed to effectively reduce those hidden impacts. Now who would have thought that?
Their model also indicated that most incidents of elephant crop damage occur within 1 km from rivers. Therefore, according to the model, it is possible to lower the risk of your crops being eaten and trampled by a grey giant by planting them further away from rivers (Yeah, good news!). Among the incidents studied, human deaths were found to be the easiest to reduce (more good news!). Fifteen out of the 18 scenarios lead to significantly fewer human deaths.
Distancing human activities from rivers, and creating conservation corridors and protected areas, seem to be an effective mitigation strategy. However, challenges remain. Reducing the deaths of elephants seems to be one of the most difficult tasks, with only six out of the 18 scenarios showing significantly fewer dead elephants. The number of elephant deaths was reduced in some scenarios, such as a so-called “ENS-River-Protect-Corridor”, in which the scientists modelled farms to be 7000 m away from rivers, protected areas and wildlife corridors.
While no single scenario that the scientists played through was able to completely eliminate all incidents, their modelling provided valuable insights and recommendations for potential strategies to reduce HEI. With their models, the researchers showed that HEI is influenced by many different factors beyond the pure numbers of humans and elephants. Geographical and environmental features, such as rivers, protected areas, and corridors, and socioeconomic activities, also play crucial roles. With the approach of creating safe distances between human activities and critical areas, the researchers found practical strategies to minimize the deaths of both humans and elephants.
The study’s findings, therefore, highlight the need to address the spatial relationship between humans and elephants and promote responsible settlement planning. Successful strategies for mitigating HEI require a holistic approach that balances the needs of both humans and elephants and prioritizes a healthy elephant population as well as the well-being of affected human communities.
It is important to emphasize that models are just a tool, implementing solutions still needs to be done by our big, juicy human brains. For example, in all scenarios, the model suggested to just lower the population size of humans and/or elephants to mitigate HEI. Fewer humans, fewer elephants: fewer human-elephant interactions. Of course, both options are far away from an ethical or recommendable solution. If the elephant density is extremely high, relocating them to other areas could be a (very complicated and expensive) option.
Wait a minute! Hey, German politicians, how come you haven’t thought about reducing the population size of humans in areas where the wolves are coming back? I heard many of us would love to live in New Zealand anyway. What about providing a free one-way ticket to New Zealand for every revengeful German sheep farmer who wants to kill wolves as a compensation measure?
Mamboleo, A. A., Doscher, C., & Paterson, A. (2021). A computational modelling approach to human-elephant interactions in the Bunda District, Tanzania. Ecological Modelling, 443, 109449. (https://doi.org/10.1016/j.ecolmodel.2021.109449)
