The urban jungle

Aneta Cichla ‘Eurobuild Central & Eastern Europe’: When we build, we take dominion of nature. We occupy the habitat of plants and animals. How can we make it up to them?

Andrzej Kruszewicz, ornithologist, director of Warsaw Zoo: The city is the quintessence of civilisation and grows out in all directions: up, down and across. When the city spills into fields and meadows, the wildlife disappears from it forever. They need an open space to live in and are unable to adapt to new conditions. The city also eats up the forests, but it does so slowly, e.g. through the creation of leisure areas. As a result, forest animals have actually learned to live alongside humans and are doing well. Most big cities are built upon rivers, so if we talk about preserving biodiversity in the city, we should think about its water- ways. They are the habitat of many species of birds. Sandbanks have been created on the Vistula in Warsaw, to allow birds to rest and nest. And this approach has succeeded. Having renovated one side of the river bank, the other should be left in its natural state. After the construction of flood embankments, enclaves have been created in the areas between them. These feature 60-year-old elms, wild dogwoods and dead trees – and wildlife can thrive there. So we need to preserve examples of the natural environment such as this.

But how can this be done when it comes to large urban projects?

If a developer cuts down a tree on a construction site, it should be replaced somewhere else on this plot. Trees play a very important part in nature and form an element of the landscape. The trees that are cut down are used by insects, which then provide food for the birds. Of course, new ones can be planted to replace them, but there are no hollows in young saplings, so they are of no use for insects. That’s why you should not remove dead trees but instead re-use them in a practical way – as an enclave for animals. Natural expanses of water are also missing from cities. So small ponds are another good idea: protected and with gentle banks – thus providing another refuge for nature. If in addition to this you leave dead tree trunks next to a pond, properly secured, then life will take hold there – it will attract insects, followed by a number of other animals. The nesting boxes that are often installed by developers are also important, but not enough. These boxes are mainly used during the breeding season and are only useful for a short time. Green enclaves, as I have mentioned, are the best way of compensating for the damage done to the natural environment.

But achieving this could be very difficult with large projects...

But it does work. The Port Żerań residential project now features a floating raft for birds. If there is a small pond on an estate, then it’s possible to think about having such a raft – as a refuge for ducks. Meanwhile, developers who build along the riverbank should leave at least one shore, one part of it, to nature. A part that is not intended for development. This can surely be organised with a little bit of good will. And it will be nicer for people to stay in a place that is full of natural life.

What are the sins that are most often committed by developers?

They often create new greenery by planting exotic plant varieties instead of native ones. Driving around the city, I have observed that about 70 pct of new plantings are foreign plants that are of no value to our fauna. Not only that, they are often harmful plants, such as azaleas, whose pollen is poisonous for bees. Firethorn is also poisonous and yet it is very popular. Trimmed lawns, planted with exotic vegetation fertilised and sprayed, are not good for the local wildlife. Quite the contrary, in fact. Black cherry is an exception to this rule – it provides food for the birds as well as for the swallowtail butterfly. As does the red oak. Lilac, rowan, sea buckthorn, hawthorn, blackthorn and wild rose all help birds to thrive. But the green areas alongside main roads are often planted with fruiting plants, which attract birds. Some, such as the waxwing, can’t judge the movement of objects speeding at more than 60 km/h and often fly into cars. Plants that could attract birds should not be added to such places.

How is the wildlife impacted by high-rise buildings in cities?

Modern office buildings constructed using glass and aluminium are not a good environment for birds. There is nowhere to live for them in them. Furthermore, office buildings also act as a bird barrier. Birds often simply don’t see these buildings and fly into them. The same can happen with glass connectors between buildings. Light pollution can also pose a hazard. The lighting for these buildings also disorientates insects, which end up flying around the lights and dying on them.

How can this be remedied?

Specially-designed glazing with threads through it that can be seen by birds can be used instead. Windows that reflect ultraviolet rays visible only to birds are also currently available. There are also plastic sheets that can be applied to glass façades. These reduce the light emissions by just 5 pct, which is imperceptible to humans. Buildings can be illuminated so that they look attractive while also existing in harmony with nature at the same time. The eastern and western walls should be properly illuminated because this is the direction birds migrate in. You can also simply turn off the lights in building at night to a certain degree. Buildings in cities are not only places for people but also homes for birds. In some cases developers have embedded ceramic nesting boxes for birds, such as swifts, sparrows and others that that nest in buildings, while constructing them. And this is a good idea because these birds eat huge amounts of mosquitoes and black flies. In Warsaw, most of them live in the Old Town – close to the river and where they have a good place to live under the roof tiles.

And what kinds of threat are posed by animals to buildings?

Martens can do a lot of damage. They can bite through cables and wires and trigger alarms. Sometimes building owners take sacks of lion and tiger poo from us and put it in the attics – this supposedly works, but only for a short time. Rats and pigeons can also be a problem. Ultrasonic sounders work the best for martens and rats. More work needs to be done with pigeons – you can remove the nests, being sensitive to breeding period, of course – but this lasts the whole year round for pigeons. You should also be careful when using spikes, because poorly mounted ones can injure pigeons.

Insulating buildings, if done the wrong way, is another issue – and one that often brings owners into conflict with the environmental protection act...

This happens when property owners make holes in flat roofs with bars, taking away birds’ nesting places and often killing them in this way. Insulation can only be fitted outside the breeding period [from October 16th to the end of February, according to the most recent legislation. Then, under certain conditions, bird nests can be removed from nesting boxes, construction sites and green areas without any permits – editor’s note]. One effective and simple solution is the assembly of nesting boxes in the polystyrene layer cladding the wall of the building.

What about biologically active surfaces? Does the laying of moss on roofs benefit nature in any way?

It depends on how the roof is structured. In order for something to survive on it, the roof has to be watered. The plants need to be properly selected: they should be native and resistant to harsh conditions, but this can be done and it can even be very nice. Trees, shrubs or grass can be planted on a roof or terrace. Beehives on roofs are also a good idea because bees seem to be thriving in them, provided they have somewhere for gathering nectar – but the city simply doesn’t have enough linden trees. These work best in sites near parks. We had beehives with chocolate-flavoured honey at our veterinary department on ul. Grochowska, because the bees were flying near the Wedel factory.

Nature man

Andrzej Kruszewicz, PhD – a vet by profession, ornithologist by passion. He is the author and translator of many publications in this field and is esteemed for his knowledge, passion and his love for his work. Since 2009 he has been the director of the Warsaw zoo. His favourite animal in Warsaw zoo is Benek – a Sichuan takin. Hanging in his office there is a painting by one of the zoo’s apes. He is also a fine storyteller, well-known for the animal stories he tells on radio programmes (Dr Kruszewicz on Trójka and Flying Radio on RDC).

Biodiversity protection and eco-certification

Marcin Gawroński, the director of the Ecological Building Department of Sweco Consulting, BREEAM International NC and IRFO assessor, assessor of BREEAM In-Use BREEAM AP and LEED GA

What do the certificates have to say about this?

In BREEAM there is a whole section devoted to environmental issues. This scheme also requires compliance with EU, national and local laws with regard to the forms of natural conservation and the regulations connected with the protection of wild plants and animals. An ecological expert is generally involved in the project certification process to draw up an inventory of such aspects and to prepare an environmental report with recommendations for the developer and the general contractor. Certification is a tool that has to make the investor carry out more than just a simple project with some greenery. At Sweco this is our job, to mobilise developers to undertake more wide-ranging activities in the field of environmental protection and increased biodiversity.

Good because it’s Polish

The BREEAM certification principles addressed to the environment stipulate that any new planting should be native and conform with the locally occurring flora. Sweco’s experts draw up a set of recommendations aimed at improving the environmental situation within a project’s boundaries, including a list of native plant species proposed for planting that are characteristic for that particular region as well as ideal for the local fauna, such as small mammals, birds and insects, as a source of food as well as a place to live. Developers generally follow the guidelines proposed. They are often unaware that certain changes can do a lot of good for nature and can also be introduced at a small cost. Preserving natural enclaves is an ideal solution from the point of view of environmental conservation. However, this requires not only the involvement of the investor or potential client, but above all the knowledge of specialists who are able to adapt traditional, natural habitats to the new urban conditions that prevail around the area of the project. But this is still a less than straightforward aim to achieve, requiring education and changes in the way people think.

Overcoming the obstacles

Providing nesting boxes for birds is another form of conservation and one of our basic environmental recommendations. After a field inspection, the expert determines whether adding the boxes is justified – and this has much to do with the location of the project. They also identify the species that could potentially make their homes in such a nest. Swifts’ nests are the most commonly chosen, while “hotels” for insects are often located in the green areas of projects in the vicinity of melliferous plants.

The natural environment can be seriously impacted by the light generated by buildings. The certification includes a separate category on how to minimise the impact of night lighting on the surroundings of the building. Glass façades can be a problem for birds but can also be adapted for them. We were faced with one such a problem in Kraków, for which we advised a range of solutions, including plastic sheets, window stripes and UV inks that can only be seen by birds.

Intensely green

Another pro-environmental measure is to install a green roof. There are two types of green roof: extensive and intensive. With the former the substrate layer is thinner. Stonecrop mats are mostly used on this type of roof, with plants that do not require large amounts of water. For intensive roofs (with taller vegetation), an appropriate irrigation system also has to be provided and a much thicker substrate has to be laid. Okre’s Grójecka Offices project on ul. Grójecka in Warsaw has such a roof. The main advantages of a green roof are the filtration of air pollution and the production of oxygen, which reduces the ‘urban heat island’ effect, while it also increases the amount of rainwater retained, reduces the heat loss in the winter and in the summer insulates the building from excessive heating. Even basic ‘moss roofing’ has benefits for the environment. A roof garden ​​can also play a recreational role and provide a place to relax in the middle of the city. Furthermore, BREEAM 2016 includes a requirement that 5 mm of the rainwater on the plot of the building should be retained and used instead of just directing it into a drainage system – and green roofs could be one way to successfuly meet this criterion.