BEHIND THE SCENES

Fold Interviews
— Chris Manderson

On wilding in the city

Chris Manderson is the Urban Conservation Lead at Calgary Parks and explores the intersection of urban ecosystem management, invasive species and planning in the City of Calgary.  FOLD interviewed Chris on April 4th, 2017.

 Fold: There’s a sense of nature as something that we must manage, that it grows fast and must be constantly maintained. As someone who has studied ecology but that also works with an urban park system, how do you see the natural environment?

Chris Manderson: I once had a conversation with someone who described humans as a species that gardens, and by that I think they meant ‘garden’ in a broad sense — that we constantly change our surroundings to suit ourselves and to favour species that benefit us — the development of agriculture is one good example of this. We’re not the only species on the planet that do this, but we’re certainly the most successful at it. There are very few places left in the planet that we have not altered in some way.

I think that our influence is present even in those areas that we see as being wild – there’s an artificial dichotomy between the natural world and our built environment. There’s a perception that natural areas (even those in cities) are ‘unmanaged’ and the built environment is not. In fact, the reality is that our natural areas are very much a product of human activity.

We manage natural environments in an effort to keep them ‘natural,’ by controlling weeds, by restoring habitats damaged by overuse or the impacts of urban development. One of the things I’ve come to see in my time in this role is that managing a natural ecosystem is best done by seeking ways to re-establish the natural processes that led to the development of that system in the first place — in a prairie ecosystem like we have here in Calgary, those processes could include things like grazing or fire, things that can be a bit of a challenge in an urban environment.

What is the relationship between the city and nature?

CM: There is a perception that nature and cities are separate entities – that those spaces and their benefits exist outside of the built environment, and outside of our cities, for that matter. That perception is certainly the case when you look at the natural areas in Calgary. Calgarians treasure their parks, particularly the wild spaces that we have – places like Nose Hill, Edworthy Park and the Weaselhead. What I find interesting is the line that we unconsciously draw between ourselves and what’s natural.

Calgary’s natural areas are as much a product of human activity as they are of natural processes – there are often non-native species and they show signs of stress from human use, which leads to a loss of species diversity.  The conventional view of such areas by a biologist is that they’re ‘degraded’ or ‘anthropogenic’ – that they’re not as valuable as an undisturbed site. This is true, and managing for this is an important part of our work, but I think there’s room to value these urban ecosystems for what they are.

Conservationist and writer Emma Marris makes the case for rethinking our approach to nature and argues that we should embrace those places that are wild regardless of whether they have a human or natural provenance. She described nature as ‘anywhere where life thrives, anywhere there are multiple species together.’ If you think about it, by this definition much of our cities are wild spaces.

Certainly Calgary is a home to more than just us—anyone who has a bird feeder in their backyard, or who has watched a coyote cross a busy road on a walk light would know this. Many species have adapted to city life, and are arguably evolving differently from their rural counterparts.

Last year your team piloted goats as a grazing management system. What was the attraction to goats and how did the pilot go?

CM: We have long been interested in grazing some of our prairie parks. The prairies evolved with grazers — think about the impact that bison had on the landscape. Prairie ecosystems do better with grazing — it helps maintain species diversity, manage the encroachment of trees and shrubs and helps prevent weeds.

We elected to bring in goats as a trial for weed control in Confluence Park. Why goats? Well for starters, they’re small and fairly easy to manage, a clear advantage over bison. They’re ‘browsers’ meaning that they tend to go after broad-leaf plants (a lot of our weeds are broad-leaved species) instead of grasses and we were using them specifically to see how good they are at weed control. We were interested to see if we could use them to reduce the need for herbicides for weed control — if properly done, a grazing program can improve ecosystem health and reduce invasive species.

The pilot was a success on all levels. They did an amazing job of grazing out the weeds throughout the entire park. Initially, we just wanted to see if we could bring livestock into a very busy city park and not have any conflicts.

What was really wonderful to see was the public response. On the final day of the pilot, we had a meet-and-greet event where the public could come out and see the goats up close. We knew there would be interest, but had no idea that we would see several thousand people show up for the event.

What is biodiversity and what does it mean for a city to design around the unique needs of habitats that are not limited to human-use?

CM: Biodiversity is quite simply the diversity of species and habitats in a given place. It’s a way to measure how rich or diverse a place is in terms of the species that inhabit it. It’s not necessarily a numbers game – more diversity isn’t always better. If you accept that cities can be a habitat for more than people, then it would be reasonable to think about how we can design cities to better accommodate other species. To me, this means thinking about opportunities to protect the core native ecosystems that we have, and to reconnect those fragmented remnants into a bigger system. It also means looking for ways to recreate natural processes that support diversity; something that could be as simple as planting more trees on a boulevard, or as complex as restoring native ecosystems.

In a talk, you showed an image of a road inside a grassland park. The road has tree sprouts shooting up through the asphalt. What’s the lesson you took from this image and why is it interesting to you?

 CM: That photo is of an old asphalt road in Nose Hill Park built as an access road up to the gravel pit on the top of the hill. It hasn’t been used for several decades. What interests me about this road is how it is slowly being broken up by the poplar trees. The roots of the trees are slowly crumbling the asphalt, which in turn creates a space for other smaller plants to establish that in turn break it down further.

Before I started this job, my initial reaction would be to remove the old road and the trees, simply because it wasn’t representative of the prairie landscape. Now when I look at it, I think it tells an important story about the industrial past of Nose Hill. Not too far away from this road there are other important elements of Nose Hill’s cultural landscape. In 2015, the Siksikatsitapi (Blackfoot Confederacy) constructed a medicine wheel as a landmark to signify their spiritual connection to the land and it’s importance to them as a place of cultural and historical significance. To me, both serve as important reminder of the influence western and indigenous peoples have had on the landscape.

What can be learned about the relationship between decay and renewal?

CM: Ecosystems are dependent upon decay and decomposition as much as they are on growth, and in fact need both in equal measure. Earlier this year, I was involved in a bank stabilization project in Riverdale where an Alberta artist, Peter von Tiesenhausen, worked with the engineering team on a flood wall. What I loved about this project was that the artist created a facade over the wall that was designed to decay. The deliberate introduction of a structure that would naturally create habitat over time (while remaining stable) made this more than a simple engineering project to me. By designing it to allow for natural degradation, it creates a substrate for life. The freeze-thaw cycle would allow for the gradual colonization of the structure by moss and lichens as well as innumerable microorganisms, which would in turn play a part in slowly breaking it down but would also create niches for other species; flowering plants and insects  and eventually mammals and birds will colonize the wall. To me, the notion of deliberate decay was as an acknowledgement of the vital role that it plays in all of our ecosystems; where we see wild spaces in a city, it is almost always with that element of decay and renewal.