Tag Archives: urban ecology

Enhancing biodiversity in cities through design

This article is republished from Cities People Love under a Creative Commons license. Read the original article.

An interview with Professor Sarah Bekessy

Sarah Bekessy is a sustainability and urban planning academic at RMIT University in Melbourne and a leading voice in Biodiversity Sensitive Urban Design (BSUD).  We interviewed Sarah to understand more about the importance and benefits of incorporating biodiversity and nature in the design and planning of our cities.

What is your role in protecting and enhancing nature in cities?

I have a background in conservation biology and have been working at the intersection of town planning and urban design, and now architecture and biodiversity conservation for quite some time. Biodiversity in cities is predominantly a human-driven concept. Tackling the issue alongside people who are making decisions about the form, design and construction of cities and how people interact with nature is utterly critical to the debate and discipline. It has been an interesting space to be part of over the last decade as it’s gone from being a peripheral issue of minor interest to people through to a completely mainstream concept that is now core to any discussion about resilience and health in cities.

What is the case for enhancing biodiversity and nature in cities?

The health and wellbeing benefits are the most compelling reason for enhancing nature in cities and a remarkable body of research has emerged in the last decade that policy makers find very compelling. Your whole health and wellbeing is influenced by the amount and quality of interactions with nature in cities and a remarkable array of physical and mental health and wellbeing benefits result from having everyday nature experiences. Further to that we know we can cool cities, reduce the risk of flood events, and generate resilience to climate change through nature in cities. If we do it right, cities can sequester as much carbon per unit area as a tropical rainforest. So we can even be part of the reversing climate change solution.

There’s also a really strong argument that unless we engage people with nature in cities we will gradually become disenchanted and disconnected with nature. There is an important educational and engagement opportunity to re-enchant and reconnect people with nature in the places where they’re living, working and playing. Nature in cities is key to place-making and connecting people with the uniqueness of the place where they’re living. Nature is how we can make cities not such homogenous, globalised places but places with their own unique stories.

Nature is also a really important way to celebrate culture. In Melbourne we have a unique opportunity to celebrate the rich Indigenous cultural heritage of our city through telling stories about nature and having return of species of significance. People want to be part of the solution rather than part of the problem, where you’re generating habitat and celebrating cultural stories through your own front or back garden.

What are the key ways practitioners need to think to better manage, incorporate and enhance nature in cities?

Broadly speaking what we’re asking people to do is turn years of training and concepts of cities on their heads.

We have historically seen cities as places to retreat from nature – safe spaces away from the dangers and threats and perils of nature. A lot of our construction and design thinking is based on that philosophy. It’s big shift to think about how we can design to embrace nature and encourage positive human wildlife interactions.

Step one is actually reframing the way that nature is conceptualised in planning and design because, despite the remarkable benefits I described earlier and the policy commitment at all levels of government, we still have planning policy that on the whole treats biodiversity as a problem and a constraint. We need to reframe biodiversity in the planning world so that it’s perceived of as an asset to be maximised, not a problem to get rid of or offset. And we have to start acknowledging that ecological knowledge is key to this. The emerging evidence is that it is biodiversity, not just ‘greening’, that delivers the maximum level of benefit to cities and the people who live in them.

Delivering biodiversity in cities is not going to be a generic box-ticking process. We have to work meaningfully and deeply with the ecological disciplines to understand what species need to persist, what resources they need, what threats they’re going to face and how to better connect the city so that they can move around and be viable. That requires deep ecological understanding. Historically there has been a strong divide between the world of architecture/design/planning and the world of ecology and conservation and I’m passionate about bringing those worlds together to achieve meaningful benefits through having rich biodiversity in cities.

Roof designed to support biodiversity – photo provided by Sarah Bekessy.
Biodiversity driven design as imagined in Fishermans Bend – concept image provided by Sarah Bekessy.

What are some of the tools you’ve been working on that can help practitioners bridge the divide between the built-form disciplines and ecological knowledge?

We have developed a protocol called Biodiversity Sensitive Urban Design (BSUD) to help developers to meaningfully build biodiversity into their designs through investigation, objective-setting, design and evaluation processes. We have been working with the development industry to implement and test the BSUD framework and build an evidence-base to support incorporating biodiversity considerations into the planning, design and construction process.

Biodiversity Sensitive Urban Design starts with investigating a development site with the mindset to seeing biodiversity as an asset, then thinking carefully about how you can be regenerative in your designs to bring species back and restore natural processes. We encourage developers to ask questions about the history of the site – what ecosystems used to exist and thrive there – then think about how that history could be reflected in designs moving forward.

Engaging with stakeholders and the community is key to determining objectives about the species and ecosystems that you want to allow to flourish or return to the site. They can be really charismatic and enchanting species or keystone species that will help attract and protect other species. When designing for different species, people often instantly think about parks, green spaces and riverside vegetation. While these spaces are critical to biodiversity in cities, BSUD recommends thinking about building requirements of species into the urban fabric itself as this is key to people engaging deeply and frequently with biodiversity and getting the most out of their interactions with nature.

We want to be building houses that both provide resources for species and mitigate threats. We can create nesting, food and water resources in our houses and gardens. And threats can be mitigated through a range of features, including the lighting that you use, the windows that you choose (i.e. bird-friendly glass), and providing nesting boxes and insect hotels. Having a garden with the features of habitat that species are going to enjoy – rocks and logs and water – or incorporating a range of species from big trees through to shrubs to an understory of herb-rich grassland. All these things are totally possible in small city-backyards. Even balconies can be rich places for providing habitat.

The evaluation of proposed designs to ensure biodiversity is meaningfully incorporated, requires more complex and scientific approaches ranging from expert opinion to technical modelling. This process helps to identify the critical components of the proposed design and any aspects that may interact negatively with other development goals. We encourage all practitioners to think through the BSUD process and consider how they could meaningfully engage with every step of the process in their project.

“For practitioners, thinking creatively and in a sophisticated way about how we can build on-site biodiversity into all of our new developments and retrofits is the key challenge.”
Planting for biodiversity in Clowes Street, Melbourne. The biodiversity impacts of urbanization can be mitigated by Biodiversity Sensitive Urban Design. A landscape devoid of vegetation other than a strip of lawn provides little habitat or resources for native species living in the grassland, this compared to a space planted with a variety of native species such as trees, shrubs and grasses.Photo credit: City of Melbourne

What can be achieved when you bring together this multi-disciplinary approach and commitment to biodiversity from the outset?

Most practitioners are linked into thinking about some of the barriers to BSUD being a reality – conflicts with fire, risk and safety issues, infrastructure damage from tree roots, and people’s interactions with nature (i.e. leaves clogging gutters, nature is stinky/noisy).

The obstacles to BSUD are numerous, but we have found design solutions to every identified barrier and we just need to test these to demonstrate their effectiveness and build an evidence base of outcomes.

We’re currently trialing the BSUD framework on two development sites with Lend-Lease and Yarra Valley Water and will evaluate the benefit and outcomes of the process. We see this is a key aspect to mainstreaming BSUD so that people aren’t afraid of the potential negatives to embarking on this process.

The economics of the approach are also important to understand to build an economic case for BSUD. How much does it add to the value of a house? Are people prepared to spend the extra amount? Or does it even cost anything extra to think differently in this way?

We also think BSUD can operate at any scale. We’re working with architects on a range of house and street-scale case-studies. Nature based solutions have become a mainstream concept in the architecture world and most state-of-the-art new building will include some sort of greening or biodiversity consideration.

But we’re still not at the point of proving biodiversity benefits and we don’t have an equivalent evaluation framework in place as you would have for carbon or water for a building. This is why we’re working with architects to build ecological thinking and biodiversity metrics into standard architectural process.

The aim is to see biodiversity evaluated in the same way that we evaluate the carbon footprint of developments and to make BSUD a mainstream approach to design to enhance biodiversity in cities for the benefit of individuals, communities and our sense of culture and place.

Find out more about BSUD, including helpful resources by visiting our BUSD webpage!

ICON at #VicBioCon21

By Katherine Berthon and Marco Gutiérrez

Last month ICON Science was a proud sponsor of the 2021 Victorian Biodiversity Conference (VicBioCon). ICON researchers also helped organise and presented at the conference. It was the first time the conference was held entirely online, and, despite some website updates during a tea break, the whole train ran smoothly!

VicBioCon is a local conference that aims to connect industry, government, and practitioners to research, and showcase local efforts to conserve biodiversity in Victoria. This year’s line-up included plenary talks from academics and professionals working with human-nature connection and threatened species conservation. It also included two outstanding panels; one on the efficacy of Australia’s biodiversity laws, and another on the possibilities for nature in the city. In the latter panel, our very own Sarah Bekessy shared her passion for creating everyday nature in cities, a topic that is especially important given continued covid lockdowns.

Plenary highlights included Euan Richie talking about what gives him hope in conservation, in a time of climate and political challenges.

Minda Murray shared about her story and the struggle of Indigenous Peoples to have their knowledge and cultural existence recognised. She ended by encouraging for collaboration and relationship building across Indigenous organisations and non-Indigenous allies.

Chris McCormack gave us two tales of development and encouraged us to build empathy for human-nature relationships through storytelling.

Lindy Lumsden delivered a passionate talk about her work with Australian bats and their conservation.

An equally important part of VicBioCon is the student and early career researchers talks which give postdocs, PhDs, and master’s students alike the opportunity to network and share their research. This year, ICON researchers participated in sessions on urban ecology, science communication, and environmental policy.

On Friday morning, in the Urban Ecology session, Katherine presented her research on using metabarcoding to determine pollinator preferences in Melbourne parks.

On Friday afternoon, in the Science Communication session, Matthew shared his expert elicitation work on cost-effectiveness of cat containment and wildlife gardening programs on conserving small mammals; and Emily mapped out the ethics behind strategic conservation messaging. Both have papers in prep, so stay tuned!

Alongside in the Environmental Policy session, Marco gave his critical analysis of the Melbourne Strategic Assessment, and Lily van Eeden (our latest ICON recruit) talked about research strategies, and collaborations necessary to encourage Victorians to value nature.

We look forward to the next edition of VicBioCon in 2022!

Invertebrate use of rooftops in Melbourne

Green roofs are a peculiar kind of designed habitat. In already highly urbanised areas, where there is large pressure on efficient land use, green roof retrofits are a key strategy to bring back nature without losing building capital.

While green roofs are known to have many economic and social benefits, such as stormwater retention and thermal buffering, their usefulness as wildlife habitat remains an open question. Multiple studies record insects, birds, spiders and other animals existing on green roofs, but there is little known as to how (and if) they are subsisting, or indeed what they are doing up there.

Native Halictid bee visiting a native Scaveola flower on the Parliament green roof. Photo Credit: Jess Baumann.

This is the focus of a new study by ICON Science researchers Georgia Garrard and Katherine Berthon, and research assistant Jess Baumann, who are setting out to document how animals (particularly birds and insects) are using green roofs in the City of Melbourne by monitoring two new green roof retrofit developments. This project is funded under the City of Melbourne ‘Green Our Rooftop’ initiative, and uses a large new green roof retrofit that is set to be constructed on 1 Treasury Place in Fitzroy, as well as the innovative Melbourne Skyfarm that will replace the top level of the Siddeley Street Carpark in Docklands.

Monitoring a green roof retrofit before and after its construction is an ideal way to answer some of the tricky questions about the secret life of rooftop animals. For example, we don’t yet fully understand the value of a single roof, the primary pathways by which animals come to live or forage on a roof, and whether there is any movement of animals between rooftops.

It is often not acknowledged that some invertebrates (like spiders and flies) and some birds (like the Peregrine Falcons nesting on 367 Collins St) are capable of using bare roof spaces. Knowing this baseline of buzzing activity helps us know what animals have been attracted after a green roof is installed. This allows us to quantify the added value of a new green roof in the landscape.

It is likely, however, that the construction of a green roof is so disturbing and prolonged for a site that it might wipe the slate clean. This is where monitoring the site immediately after construction is important – it tells us the first-comers, and potentially highlights stowaways that have been transported onto the roof with the plants or in the soil. Perhaps surprisingly, snails have been found in large quantities on some green roofs, many stories high – likely as a result of hitch-hiking on plant material during roof installation.

We will also monitor nearby ground sites that might act as sources of animals that appear on the new green roofs. This may also show whether anything that is transported onto the roof might spill over into adjacent environments. Often soils and plants used in green roof construction come from far away, and can create assemblages of species that are atypical of the regional area. Finally, monitoring adjacent roof sites helps answer whether there is any spill over effects that might generate synergistic or additive effects of multiple green roofs popping up in the landscape.

During our study we will also be recording specific plant-insect interactions so we can not only know what insects are up on the roof, but what they are using it for. Pre-covid lockdown we had just finished collecting the baseline data to show what’s happening before the roofs have been constructed. Not surprisingly there wasn’t much happening on the bare roofs except for a few spiders and flies, whereas ground sites were still bustling with summer insect life.

At the end of our study we hope to know a little more about what makes a green roof good for biodiversity. Importantly, we want to avoid making roofs that act as “ecological traps” by enticing animals to live there without adequately fulfilling their life-cycle needs. Already we know that some ground nesting birds, whose nestlings are left to fend for themselves after hatching, find low reproductive success on green roofs. Solitary bees also struggle to produce viable offspring on roofs above 5 stories high. So, how do we create green roofs that provide the right resources, especially for breeding? To stay tuned follow the ICON blog or follow me on Twitter @CityKat75

References:

Baumann, N. (2006) Ground-nesting birds on green roofs in Switzerland: Preliminary observations. Urban Habitats 4 (1), 37-50.

MacIvor, J.S. (2015) Building height matters: nesting activity of bees and wasps on vegetated roofs. Israel Journal of Ecology & Evolution (ahead-of-print), 1-9.

Madre, F. et al. (2013) A comparison of 3 types of green roof as habitats for arthropods. Ecological Engineering 57, 109-117.

Williams, N.S. et al. (2014) Do green roofs help urban biodiversity conservation? Journal of Applied Ecology 51 (6), 1643-1649.

Shafique, M. et al. (2018) Green roof benefits, opportunities and challenges – A review. Renewable and Sustainable Energy Reviews 90, 757-773.

Trees are hot news this year

Danish Street Trees

Danish Street Trees. Image: Thami Croeser

First it was the hopeful-but-questionable ‘One Trillion Trees’ initiative, announced at the World Economic Forum in Davos, with supporters as diverse as Jane Goodall and Donald Trump. At the same time, large areas of Australia were on fire – in total, estimates are that we lost 20% of our forest cover in the climate-change-driven ‘Black Summer’ fires that only recently subsided.

Recent collaborative research from our lab brings the focus back onto our urban trees. While a few billion hectares of new forest may slightly slow climate change at a macro level, we also need immediate solutions in our cities. In the places that most of us live and work, trees have an important role to play in helping us adapt to the warming (and flooding) that’s already locked in.

The thing is, we’re losing quite a lot of trees to construction, and even well-resourced teams are working hard to keep ahead of losses. In a new paper, Thami Croeser (ICON Science) led a team which found that The City of Melbourne has lost over 10,000 street trees in the decade of 2008-2017; 2000 of these were within 10m of a major development.

Thami_image001

The good news is most of these were small trees, possibly reflecting the city’s tough controls on tree removal.  The original research was published in Sustainable Cities and Society; we also had media pickup from The Conversation and Domain, where we talk a bit about how improvements in tree planting, tree protection and building greening can all play a role in keeping our cities green as they grow.

Thami Croeser

 

The Little Things that Run the City

The little things that run the city 201115 (lowres)-1

How many insect species live in your city? How are they distributed amongst the city’s green spaces? What are the ecological processes they perform and ecosystem services they deliver? What are their most frequent ecological interactions?

The Little Things that Run the City is a project that aims to address these and other questions within the boundaries of the City of Melbourne, Australia. Results stemming from this research are contributing to identify particular insects with key functional roles that benefit human city dwellers, determine where to prioritise conservation activities, guide the design and maintenance of green spaces, and assist city’s decision-makers in considering insects in broader biodiversity plans and strategies.

The project was inspired by Edward O. Wilson’s famous quote “…let me say a word on behalf of these little things that run the world”. Almost 30 years ago, he was keen to see that the circle of concern for animal conservation was beginning to encompass non-vertebrate animalsIn this project we sought to further expand this circle so that it may also encompass the conservation of insects and other invertebrates in urban environments. Join us as we say a word on behalf of the little things that run the city.

Cover artwork by Kate Cranney.