Showing posts with label Urban. Show all posts
Showing posts with label Urban. Show all posts

Wednesday, September 7, 2016

Where the wild things are: the importance of urban nature

Cities represent our ultimate domination over nature. They are landscapes that are completely modified to meet all of our needs and desires. In cities we drastically change the vegetation, reroute rivers, seal the Earth’s surface in impermeable cement, and often change the chemical composition of the air around us. For most people, this unnatural state of affairs seems completely natural. Its how we grow up.

What we don’t notice is all that is missing. The trees, the birds, and the mammals are largely absent from big cities. But not all cities are equal in this missingness. For those of us that live in cities like Toronto, Nashville, or Sydney, seeing birds and mammals is part of our normal life. In my back yard in Toronto, I am likely to see racoons, skunks, possums, red squirrels, eastern grey squirrels, chipmunks, deer mice, and a plethora of birds, and just down the road, foxes, coyotes, and deer are not uncommon. One morning I heard a ‘thud’ come from our sunroom window, and outside was a stunned red-tailed hawk (he was fine in the end). These cities are evidence that nature can persist and coexist with urban development.

However, there are other cities where nature is almost completely absent. While living in Guangzhou, China I saw just cats, dogs and rats, and barely any birds –shockingly no pigeons. Recently in while in Montpellier, France, it became obvious to Caroline and I (the two EEB & Flow contributors) that besides a small lizard species, pigeons and a few sparrows, we were not going to see any wildlife in the city. Guangzhou and Montpellier are very different cities in terms of size (16 million vs. 300 thousand), density, building height, pollution levels, etc.  But one way they are similar is that they are old. People have living and changing the landscapes in these regions for thousands of years. Of course the same could technically be said of North America and Australia, but the magnitude and intensity of human modification has no parallel in North America and Australia. Long-term intensive human activity removes other species in the long run. Is this the natural endpoint for our younger cities?

Cambridge, England. While quite beautiful, it is a typical old european city with a lot of stone.

Why we should celebrate raccoons

Toronto has a war against the raccoon. To most Torontonians, the raccoon is a plague –vermin that get into garbage cans and pull shingles off of roofs. Their density in Toronto is about 10 times higher than in wild habitats and many people in Toronto support removing them all together.

I have a different stance. We should be celebrating the raccoon. Yes raccoons cause problems; yes they carry disease; yes they damage property; yes their density is unnaturally high. But the same can be said of people (I don’t think I ever caught a flu from a raccoon). If raccoons were to recede to distant wilds and disappear from Toronto altogether, we would be no different than all those other cities where nature has completely lost. Raccoons give hope –hope that nature can flourish under the repressive and cruel dominion of urban centres. Raccoons remind us that nature has a place and can thrive in cities, and that we can share this world. They give me hope that Toronto’s destiny is not prescribed and we are not bound to the same fate as so many other cities.

I have a couple of new Chinese scientists visit my lab each year, and the differences between Toronto and say Beijing or Shanghai could not be more stark for them. To see deer, squirrels and raccoons in the city is a marvel. Every time one of these visitors comments on the wildlife in our city, I am reminded that we are really fortunate and have something that should be cherished.

Raccoon family –not an uncommon sight in Toronto (CCBYgaryjwood

Need to rethink urban nature

The problem is that Toronto, and most other cities, is continuing to grow and become more densely packed, making it more difficult for nature to endure. We need to rethink how cities grow and develop, and we need to keep a place for nature. There is no reason why new developments can't accommodate natural elements and green space –this often does not happen in most cities. Singapore is unique in this sense, new public infrastructure projects explicitly incorporate novel green space and infrastructure. I toured green sites there recently and saw a new hospital where it was impossible to tell where the park space ended and the hospital started (see picture below). There I saw patients tending gardens on the roof, nearby residents strolling through the forested courtyards, and turtles, wading birds and a large river monitor in the neighbouring pond. Also, Singapore's new large pump house infrastructure that reduces flooding in the city has a full sloping lawn on the top that is used by picnickers. In most North American cities this type of building would be grey industrial cement with little other function than to house pumps.

Singpore's Khoo Teck Puat hospital -the world's greenest hospital? 

Large old cities devoid of wildlife need not be the natural endpoint for a city.  Smart development and accommodating nature needs to be woven into the tapestry of cities. Toronto’s raccoons are great, and I wouldn’t want to live in a Toronto without them.

Wednesday, August 31, 2016

#EcoSummit2016: Conferences –the piñata of ideas.

One of the greatest benefits of attending conferences is that they represent learning opportunities. I don’t necessarily mean learning about new techniques or analyses, though you can undoubtedly find out about these at conferences, but rather conferences are opportunities to hear about new concepts, ideas and paradigms. In some ways conferences are like a piñata of ideas –they are chalk full of new ideas but you never know which you’ll pick up.

Ecosummit is not the typical conference I go to, it is much more diverse in topics of talks and disciplines of the attendees. This diversity –from policy makers, to social scientists, to ecologists, means that I am exposed to a plethora of new concepts. Here are a few nuggets that got me thinking:

  • Knowledge-values-rules decision making context. Policy decisions are made at the interface of scientific knowledge, human values (what is important to people –e.g., jobs), and rules (e.g., economic laws). This seems like a nice context to think about policy, though it is not clear about how we prioritize new knowledge or alter values.


  • Adaptation services. I work on ecosystem services (e.g., carbon storage, pollination support, water filtration, etc.), but I learned that ecosystems also provide adaptation services. These are aspects of ecosystems that will help human societies adapt to climate change (e.g., new products).

  • Trees and air pollution. The naive assumption most of us make about trees in urban areas are that they improve local air quality. However, I saw a couple of talks where this may not necessarily be the case. Some species in North American (red oak, sweet gum, etc.) release volatile organic compounds. Spruce plantations may not take up nitrogen oxides, and in fact might release it. Thus we need to be careful on how we sell the benefits of urban trees.

  • Transformative. This is a term I have certainly heard and used before, but in listening to a wide variety of talks, I realize it is used in different contexts to mean different things. I think it best to avoid this term.

  • a-disciplinary.  I heard a guy say in a talk that he was a-disciplinary and so was not bound to the dogmas and paradigms of any discipline (I already have a hard time wrapping my head around interdisciplinary, multidisciplinary, transdisciplinary, etc.). He then presented a new paradigm and a number of prescribed well-formulated tools used to move from idea, communication, to action. I think the irony was lost on him.

Saturday, February 6, 2016

Reining in traffic –looking to China for solutions?

Human impacts on landscapes are immense. Urban areas represent complete transformations of the geological, hydrological and ecological norms in landscapes. But while urban effects are concentrated to relatively small areas, the roads and rail lines feeding cities create a pervasive and diffuse network of negative impacts. Roads funnel rain runoff and can cause local flooding and this runoff also concentrates pollutants. Further, roads alter wildlife movement. For example, the fragmentation of formerly continuous forest in Florida is worsened by large busy roads, and black bears there are unable to move long distances to find mates. The result of this is that the Florida Black bear populations are getting smaller and more genetically inbreed.

Roads are created to meet traffic demands. The more people drive and the further they drive, the more roads we build. Cities around the world are growing, meaning that more cars are concentrated in small areas. The increase in automobile use also has direct environmental consequences. Cars, thanks to their internal combustion engines, add pollution to our local environments –carbon monoxide, particulate matter, and other toxins create smog, exacerbate respiratory ailments, and contribute to global warming.

More cars also means more traffic congestion and greater difficulty in getting from A to B, meaning that we spend more time travelling to, instead of being, somewhere. Heavy reliance on automobiles directly affects our quality life in both positive and negative ways.

1950s traffic jam in Los Angeles (from Wikipedia)
Given the undesirable consequences of cars, many cities try to reduce car use. In North America, cities employ a number of strategies, including: minor improvements to public transit (while often passing on the costs to riders), creating car free zones (which have been very modest in North America, whereas European cities have been much more successful –Montpellier, France is a great example), introducing tolls, and limiting parking in the city core. It is safe to say that the North American approach to dealing with traffic has been less than spectacular –just drive through Toronto or Los Angeles during rush hour.

Living in China for the past several months, I have been intrigued by how Chinese jurisdictions have dealt with traffic. And traffic was something that needed dealing with here. In the late 1990s and early 2000s, thousands of new cars were added to roads every single day.  The air quality in China is abysmal and having hundreds of millions of cars driving at the same time only make things worse. So governments in China decided to experiment with ways to reduce automobile use.

In China, much of the power to control automobiles resides with municipalities –they are the ones who set local traffic laws and issue license plates. From conversations with scientists from different regions of China, I have compiled ways different municipalities deal with traffic and reduce automobile use. Here are some of the ways that municipalities try to reduce automobile traffic:

1) Massive investments in public transit

There can be no real traffic solutions without building fast, efficient and affordable public transit. China has been a world leader in public infrastructure development over the past ten years. For example, Shanghai has one of the largest metro systems in the world, and has opened a new line every other year since 1999! They are currently building two new lines, which will give Shanghai 18 metro lines and about 400 stations. In Guangzhou, where I currently live, they also have a very modern and rapidly expanding metro system. Guangzhou currently has 8 lines with 4 more under construction! In all the Chinese cities I’ve been in, the metro systems are modern, efficient, heavily used, and very affordable. In Guangzhou, a bus ride works out to be about 35 cents US and a metro trip to the airport (the longest trip you can take in Guangzhou I believe) is about $1.15 US.

In Toronto, where I normally live, and like most other large North American cities, subway construction has not been sufficient to keep up with population growth. Local politicians seem to be unable to make the tough decisions to get public transit infrastructure built. But this infrastructure is the linchpin for any successful reduction in automobile usage.

2) Driving days

During the 2008 summer Olympics, Beijing created a system where cars were allowed on the roads only on certain days. Which days people could drive their cars depended on the last number of their license plates. This scheme was successful in reducing traffic congestion and air pollution. Since then, they have periodically reinstated this policy, especially during extremely bad air pollution days. I was there in early December, and road sharing was in effect then.

3) Making license plates really, really expensive (or difficult to get).

In Guangzhou, Beijing, and Shanghai, getting a car is easy, but getting a license plate, now there is the real hurdle. Since 2012, Guangzhou and other cities have severely limited the number of license plates issued, and now people can get a plate in one of two ways in these cities: by joining a lottery or going to an auction. In the lottery, a person submits an application and waits for the results. One person told me it took them three years to get their plate in the lottery. In the auction, the plates go to the highest bidder and the price for a license plate at auction has sky rocketed. A person told me that plates at auction now go for more than 60,000 RMB (about  $10,000 USD), which costs more than an economy car here! This person also quipped that the plates have become more of a status symbol than the actual car.

4) Your license plate will die

In Guangzhou and other cities, license plates expire. No, not like they expire in North America where you pay an annual license fee. They expire after 10 years and are no longer valid, and the driver must re-enter the lottery. 

5) Pay the toll

Many of the intercity highways have tolls here. While this is not a policy that affects travel behaviour within cities, it does influence driver choices traveling outside the city. Tolls only work when there are decent alternatives, and the rail system in China is excellent. There are frequent trains and many high speed lines in operation (where the trains go faster than 250 km/h). We don't have many toll roads in Ontario, but the one we have near Toronto, hwy 407, doesn't go into the city (so doesn't influence commuter decisions), and does not have viable options for alternative travel. This highway is an example of poor government policy and it was one of the worst policy decisions by a government who thought private companies should run public infrastructure. Its nothing more than a cash grab that doesn't serve the broader good. But I digress.

I have been struck by the variety of approaches and the experimental nature of policy making. What I mean by experimental, is that some policies seem to be ‘test run’ to see how people respond and if the policies result in the desired effects. China is able to institute creative and extreme measures because of the government’s unique ability to change policy without public debate. Often these policies are instituted overnight with little warning. In China, people seem to take government edicts with a “well, what can you do?” attitude. But if there is a country that can change the automobile culture, China is a good candidate. They did change what a family was with the one-child policy.

While most North Americans would certainly have a problem with the lack of transparency and seemingly impulsive nature of government decisions, China is providing the world with working examples of how to reduce the number of automobiles. It is clear to most, that without strong governmental leadership, a robust set of policies, and massive infrastructure investment, heavy automobile traffic will be unavoidable.

Monday, November 2, 2015

The Toronto Salmon Run

Guest Post by Sara Bowman, currently enrolled in the Professional Masters of Environmental Science program at the University of Toronto-Scarborough

The Toronto Salmon Run

Toronto has been called a lot of things, but I think my favourite is “A City Within a Park”. Between High Park, the Rouge, and countless other parks based around our river systems, there are so many opportunities for people to connect with nature and forget they live in a city that is 2.6 million people strong. Despite my frequent excursions into the parks of Toronto, I still will often see something new that spurs a whole whack of questions and excitement about the area I call home.

Case in point: the salmon run! Cycling to work on October 13th I was lucky enough to witness my very first salmon run along the Don River, between Sheppard and Finch. You couldn’t help but notice the nearly 2 foot long fish struggling northward against the current, especially when a few individuals would have a violent encounter followed by swimming speedily away. I whipped out my cell phone and took as many videos and pictures as I could without being late to work. All throughout my shift questions started cycling through my head. Where in the river do the fish spawn? How many types of salmon are in Lake Ontario? Where did they come from? How are they faring from a conservation perspective? In no particular order, here are some answers I found to these questions!

Photo Credit: Tony Bock, The Toronto Star
First of all – I think my salmons were Chinook, which is the largest of the Pacific Salmons[1]. Chinook Salmon were intentionally introduced to Lake Ontario some time in the 1960s (Coho Salmon, another Pacific Salmon species, was introduced at around the same time), mainly for sport fishing, and as a bio-control for non-native fishes[1]. Their introduction was also important for essentially replacing the native Atlantic Salmon and Lake Trout, which were the top predators[1]. Atlantic Salmon were extirpated from Lake Ontario in the late 1800s due to fishing pressures, and today programs like Bring Back The Salmon are undertaking re-introduction efforts, and also habitat restoration and public outreach so that extirpation doesn’t just happen again[2].

Although thousands of individuals of Chinook are stocked in Lake Ontario every year, it is believed that natural reproduction occurs, and that they are well on their way to becoming naturalized[1]. In an ocean system, Chinook Salmon migrates up streams (the ones where they were born) from the Pacific Ocean to mate and lay eggs (spawn). Once they have spawned, they die, unlike the Atlantic Salmon which makes the trip back down to the Ocean after spawning[3]. The adult female will choose a site to make her “redd” (essentially a nest for the fish eggs) based on the water velocity and depth, and on the composition of the substrate, which should be gravel[3]. At first I was confused about how the fish managed to get so large in just a year, but it turns out that once they hatch after 3-5 months, they can spend up to 2 years in the streams where they undergo certain changes to prepare them for salt-water life[3]. Once they are back in the Pacific, they will stay there to feed and grow for up to six years[3]!

Lake Ontario is home to seven species of fish in the family Salmonidae, of which only 3 are native: the Atlantic Salmon, the Lake Trout, and the Brook Trout[1]. The Brown Trout, Chinook Salmon, Rainbow Trout, and Coho Salmon were all introduced[1].  My first thought, and this may be yours to, is how Atlantic Salmon could be considered native to Lake Ontario – after all “Atlantic” is in their name, and the distance between the Atlantic and Lake Ontario is pretty far, even for a determined migrating fish. So how did the fish get into our lakes? The Ice Age. The last one ended about 12,000 years ago, and Toronto was under about a kilometer or two of ice. When the glaciers retreated northward, basins were carved into the land and were filled with the melted water, and because of all the extra water from the ice, the St. Lawrence connection between the lake and the ocean was stronger[4]. Because the Atlantic Salmon had some freshwater adaptations for when it was spawning, it was able to naturalize to its new all freshwater environment[1].

National Oceanic and Atmospheric Association, 1999 

As the 2012 Fishes of Toronto report explains, as settlement around Lake Ontario and its streams increased in the 1800s and 1900s, the river temperatures increased, erosion increased, pollution from sewage increased, and physical structures blocking migration like dams were built. This would ultimately result in the local demise of the species from Lake Ontario.  Luckily, as I mentioned above, restoration efforts are under way to restore Atlantic Salmon populations. I wondered whether or not here might be some detrimental effects on any of the salmonid populations when or if Atlantic Salmon makes a come back, but a study in Ecology of Freshwater Fish from 2012 by Jessica Van Zwol and others found that a mix of Atlantic Salmon, Brown Trout and Rainbow Trout in stream breeding grounds did not significantly impact productivity[5]. Lake Trout is another native of Lake Ontario that suffered major population declines. In the 1970s some restoration efforts were began, but today the population has to be maintained by fish reared in a hatchery – the amount of natural reproduction occurring is not enough to prevent the species from extirpation[2].  

What can we do to ensure the future of these top open-water predators in Lake Ontario? For starters, we can be more conscious of what we are putting down our drains – it leads to the rivers and can pollute them. Be aware of proper chemical disposal. You can engage in tree planting programs along riverbanks to help prevent erosion. You can even help with salmon hatchery programs and habitat restoration to help give the populations a boost so that they can maintain their ecological roles, and be around for fishers to fish for generations to come.

Thanks for reading!!


1.Fishes of Toronto: A Guide to Their Remarkable World. City of Toronto, 2012. URL: Of Toronto/Toronto Water/Files/pdf/F/Fishes of TO_PRINT_Feb23%5B1%5D.pdf
2. Lake Ontario Atlantic Salmon Restoration Program. Bring Back the Salmon Lake Ontario. 2013. URL: 
3. Chinook Salmon. NOAA Fisheries. Updated May 14, 2015. URL: 
4. About Our Great Lakes: Background. National Oceanic and Atmospheric Administration. 
[U.S. Army Corps of Engineers and the Great Lakes Commission] Published 1999. URL: 
5. Van Zwol, J., Neff, B., Wilson, C. 2012. The effect of competition among three salmonids on dominance and growth during the juvenile life stage. Ecology of Freshwater Fish. 21: 533-540. Accessed online: Zwol et al_Salmonid Dominance.pdf