New York: where the streets are paved with hot dogs, donuts, burgers – and hungry insects

If you don’t finish it the ants will. Image: Rowan Peter, CC BY-SA.

New York is one of many cities whose mythical allure claims that the streets are paved with gold. Sadly, you are more likely to be treading on – or at least wading through – the remains of burgers, hot dogs, sweets, cookies, fries and more unmentionable sources of nutrients. Yet in among all that detritus is an awful lot of energy, a resource that could underpin a complex ecosystem.

Food webs are a staple of ecology research, but usually explored in rain forests and coral reefs, ponds and savannahs. However a team at North Carolina State University has recently turned its attention to the much more dangerous terrain of Manhattan to find out if the insects living on and under the streets clear up a significant amount of the food litter – and whether the diversity of species makes any difference. Their results are published in the journal Global Change Biology.

The precise relationship between resources and the diversity of flora and fauna in ecosystems has been the subject of intense research ever since the coming of the word “biodiversity” in the late 1980s. Ecologists were challenged to explain the role of species: does it matter how many there are, does the number of species affect the way ecosystems work, what do all these species do for us?

If insects could evolve to exploit the modern city, they might end up like these pizza beetles. Image: Mike Jeffries.

All this activity drives the natural ecosystems which keep us alive. Ecosystems are more productive, efficient and resilient the more species they contain, perhaps because different species carry out complementary roles or, however unwittingly, benefit the activities of others.

Hitting the streets

The North Carolina team set out to test whether the diversity of invertebrate street life affected the removal of food that had suffered “improper disposal” (a charming politeness runs through the whole study) in the parks and elongated traffic islands of Manhattan.

To audit the pavement biodiversity, the team collected insects from among the leaf litter, with additional forays into other areas in search of ants. The rate of food clear-up was measured by putting out potato chips, cookies and hot dogs and seeing how much was left the following day. Some of the food was protected by wire mesh, others not – so that larger creatures such as rats and pigeons could get in too, to allow for their impact. The precise brands of crisp, cookie and hot dog are detailed, each cut up into more appetising chunks.

This is important, allowing experimental replication with street food around the world. For example in Britain the late-night kebab might be a significant bio-geographical variation. The rate of food clear-up was compared to the overall diversity of invertebrates and the precise mix of species. Sadly, nowhere do the team members outline how they explained any of their activity to passing policemen.

Garbage guzzlers

The speed with which food was removed proved startling. In the first run of the experiment using small chunks of food, 59 per cent was gone within 24 hours. A second run using larger portions resulted in a 32 per cent loss within a day. Whole cookies and chips, gone; chunks of hot dog vanished.

The insect life on the traffic islands consumed supplies two to three times faster than the inhabitants of the parks. Life in the fast lane perhaps, or maybe the park life was more used to ice creams and sandwiches. In either locality, hot dogs were preferred to the light snacks.

In total the insects from the medians and traffic islands of two long Manhattan streets – Broadway and West St – could remove the equivalent of 600,000 potato chips per year. This could become a standard measure of invertebrate junk food ecosystem services.

Pavement ant: a hot dog’s worst nightmare.AntWeb, CC BY

The overall conclusion is that our invertebrate neighbours in the city make a notable contribution to the removal of litter. However the food clear-up was not affected by the diversity of species. More important was the presence of one species of ant, the perfectly named pavement ant, Tetramorium caespitum. Two to three times more food was removed where these particular ants were present.

There is something particularly pleasing about it being the pavement ant. Not just the name; this ant is not a native New Yorker, but an immigrant from over a century ago, probably coming from Europe to the Big Apple.

Urban wildlife is often rather overlooked as a sorry mix of second-rate left-over habitats and dodgy aliens. However the city represents a whole new habitat, likely to become ever more widespread; a zoopolis, with a distinct and fascinating ecology. Where the streets are paved with last night’s food, these ants have certainly found their niche.The Conversation

Mike Jeffies is a teaching fellow in the ecology department at Northumbria University, Newcastle. 

This article was originally published on The Conversation. Read the original article.


Jane Jacobs and Le Corbusier would agree on one thing: we need more social housing

Unite d’Habitation, Marseille. Image: Iantomferry/Wikimedia Commons.

Much has been written in CityMetric and beyond about the urban planning debates of the 1950s and ‘60s, that came to be characterised as a battle between master-planning and preservation. One side of the debate was personified by the father of modernist architecture, Le Corbusier, whilst the counter-argument was advanced by writer and journalist Jane Jacobs.

But when it comes to London’s housing crisis, aren’t there a few things that these two would actually agree on?

Jane Jacobs’ writing about the organic nature of self-organising communities, demonstrated, in her words, by the “intricate sidewalk ballet” of inner city neighbourhoods, should be required reading for anyone interested in how cities function. But today, Jacobs is increasingly invoked in attempts to oppose new developments of any kind. Her role in conceiving Manhattan’s West Village Houses, a low cost rented housing scheme built through New York State’s Mitchell-Lama Program, is unfortunately much less well known. It’s been suggested that if Jacobs were around today, she’d be working with New York’s housing activists. When her seminal work The Death and Life of Great American Cities was written, there were almost 2 million rent-controlled or rent-stabilised apartments in New York City; nowadays, there are fewer than half that number.

Le Corbusier, on the other hand, is too often blamed for drab high-rise blocks. But regardless of how well his followers across Europe interpreted his ideas, Le Corbusier’s vision for cities was about high quality residential blocks that also contained shops and leisure amenities and were surrounded by parkland – the original mixed use development if you like. His most famous building, Marseille’s Unite d’Habitation, consisted of 337 apartments with views of the mountains and the sea together with shops, a restaurant and a nursery school. The building was originally intended to be public housing, but the French government eventually sold off the flats to recoup costs. Alton West Estate in Roehampton and Park Hill in Sheffield are just some of the examples of Le Corbusier’s influence on the design of post-war council housing here in the UK.

Building homes for a serious business in post-war Britain. Under Attlee’s 1945 Labour Government, 700,000 new council homes were completed. In 1952, the largest architectural practice in the World was at London County Council, with 1,577 staff including 350 professional architects and trainees. These were the days of consensus, and very quickly Tory governments were actually competing with Labour governments about who could built the most council homes.

Some of the council homes built post-war have stood the test of time better than others. But what’s not in doubt is that building council homes on such a scale immeasurably changed the lives of so many families in desperate need of a decent, secure and affordable home. And so many of the post-war modernist high-rise blocks so despised by Jacobs quickly took on the organic self-organising traits that she held in such high regard and have become some of the most enduring and closely-knit communities in London.

Fast forward to 2019 and Right To Buy continues to decimate council housing stock, but perversely home ownership seems more out of reach than ever for so many. An entire generation is being forced to embrace long term private ting in a country that has some weakest protections for private tenants in Europe. Meanwhile, government spending on building new homes fell from £11.4bn in 2009 to just £5.3bn in 2015 – from 0.7 per cent to 0.2 per cent of GDP – and since then, the housing minister’s desk has been occupied by no fewer than six people.

So what would a comprehensive drive for new council and social housing on the scale of the 1945 government’s efforts look like in 2019?

Lubetkin, the architect responsible for Islington’s Spa Green Estate and Bevin Court, summed up the spirit of post-war council home building with his maxim that “nothing is too good for ordinary people”. It’s a vision that we’re trying to recreate through our own council home building programme in Islington.

One of the best opportunities for small council home building schemes is to expand upon existing communities. The vast majority of Islington’s new council housing takes the form of infill, construction on existing estates; in unloved spaces, in old garages, and in old undercrofts. These projects often involve landscaping and new amenities to enhance rather than reinvent local communities. We have built community centres and even rebuilt a library as part of council housing schemes. One Tenants’ and Residents’ Association had an idea for a new specialist over 55s block for the older residents of the estate who wanted to stay in their community.

But there’s a place for large-scale place making as well. When the Ministry of Justice closed Holloway Prison and announced that the site would be sold, Islington Council published a Supplementary Planning Document (SPD) on the site. We had one aim – to send a clear signal to the market that anyone who was looking at buying the site needed to be aware of their planning obligations. Most importantly, any development on the site needed to include at least 50 per cent genuinely affordable homes. The speculation around the site came to an end on 8 March this year when Peabody Housing Association announced that it had bought it. It has committed to going well above and beyond our planning requirements, by making 600 out of a total 1000 homes genuinely affordable homes, including 420 homes for social rent. We need to see more detail on what they are proposing but this is potentially brilliant for the borough. A local grassroots group, Community Plan for Holloway, have been instrumental in ensuring that the community’s voice is heard since the site was sold.

To recreate the scale of the massive post-war council home building programmes would require a Jane Jacobs inspired level of community activism combined with the architectural idealism of Le Corbusier. But it would also need the political will from central government to help local authorities get council housing built. And that, sadly, feels as far away as ever.

Diarmaid Ward is a Labour councillor and the executive member for housing & development at the London Borough of Islington.