CITIES and towns are not just concrete jungles. Even in heavily built-up areas there are some forms of wild life. In the middle of Amsterdam, there is a large heronry. You can count dozens of nests in tall trees near the university. Hedgehogs abound in Berlin parks, and the foundations of a church in Dublin are threatened by badgers. In Britain, wherever you are, in a town or country, street or lane, you are never very far from nature. As an experiment, see whether you can find any place, even in large busy shopping areas, where absolutely no form of natural life is visible except men and women, cats and dogs. There are gardens, parks, squares, playing-fields, car parks, and laybys. A step or two in any direction will bring into view a pigeon strutting on the ground, a few sparrows on a telegraph wire or roof, a gull soaring overhead, a fragment of moss at the foot of a drain, or a plant of shepherd’s purse or sow thistle struggling in a gutter. This is because nature is infinitely resourceful, being quick to seize on any available empty space. You can test this by leaving a seed box of sterilized soil lying outside. Before very long seedlings of some sort will colonize even that small empty space. Or you can paint a part of a wall with some sticky liquid, and see what seeds come floating by to stick fast to it. Soldiers in the First World War reported that small birds were nesting and breeding in no-man’s-land – the strip of land between the trenches – even during periods of great disturbance. If man ceased to exist, all our cities and towns would soon be covered with some form of vegetation, with its accompanying birds, insects, and animals.
BIRDS IN TOWNS
The most successful adaptation to urban conditions is found in birds, and the most urban bird of all is the pigeon. The sort found in towns is not the wood pigeon of our fields and farms, but a descendant of the rock dove, and it has found the buildings and roofs of towns an admirable substitute for its former rocky habitats. Trafalgar Square, in London, has many thousands of them feeding there every day. So has St. Mark’s Square, in Venice – a very different place, but just as convenient for pigeons. In many cities they have become a pest. They live in squares and streets, near docks, railway stations, embankments, and open air cafes, wherever people congregate and are willing to feed them. Notices at main line stations in London threaten fines for feeding pigeons, but people take no notice. A study of pigeons in Leeds showed that in winter they lived almost entirely on scraps, including bread, cake, chocolate, and anything else they were offered or could snatch. At other times they find more of their own food in fields and gardens. The most devoted lovers of nature would agree their numbers are far too great for cleanliness or comfort. Many different methods of keeping their numbers down, or getting rid of them entirely, have been tried without great success. It would be interesting to watch for them in different towns, to see how widely conditions vary, whether there are some towns without pigeons, which of the others suffer most, and why these differences occur.
The nuisance value of starlings in towns is just as great. This is another example of a too successful adaptation. Indeed the starling has shown itself to be marvellously good at survival. In America today there may be about 50 million starlings, and all of them are descended from a few dozen released in Central Park, New York, not so very long ago. In Britain, both in town and country, it seems that conditions for breeding success are just too favourable, and there are no powerful controls keeping the numbers down. Man’s presence is a help, instead of a hindrance, to both pigeons and starlings. Even city lights favour them, by helping to raise the temperature and giving more hours of light. In central areas the noiseof starlingsoften drowns the roar of traffic. Although their habit of roosting on trees and buildings in towns is a comparatively new one, seen in London only in the last fifty years, the birds are intensely conservative, using the same places regularly, and each having its allotted space. If one bird drops out, it may be clays or weeks before the gap in the roosting line is filled. They perch about four inches apart, just within pecking distance.
Starlings are more spectacular than pigeons, because they fly together, literally thousands at a time. They fly over in the winter dusk, black against the sky, wheeling and turning, gathering together until they all make for their roosting places. There are millions of them in the air at once, in a late winter afternoon. Their biomass – the total weight of living matter they represent – is as great as that of many other species of birds put together. Mysterious objects observed on radar screens, over the east of England, at first thought to be invading aircraft, turned out to be massive flocks of starlings. They are noisy, aggressive, dirty birds, doing much harm in chimneys, gutters, and on the frontages of buildings. But they are very entertaining to study, quarrelling, mimicking other birds, and behaving like a dominant species, at any rate with other birds, although they fly away if man gets too close. Starlings and pigeons are not on the list of birds protected in Britain.
Much more welcome birds in towns, because less obtrusive, include sparrows, cheeky but wary; black-headed gulls, now a familiar winter sight scavenging in London and other towns, coming inland up rivers, streaming out in the late afternoon, towards reservoirs and estuaries for the night; and other birds more rarely seen, such as the black redstart, first attracted to bombed sites in towns. Two summer visitors are swifts and house martins. House martins build their characteristic nests of mud and clay on the walls of houses, just under the eaves. They stay in England from April to October. A martin’s nest on a house is said to bring happiness, and martins sometimes nest in the same places from year to year. You can often spot where their nests are by droppings on pavements, underneath the nests, and this would make it easier, in a small country town or part of one, to do a survey establishing how many nests there are and how they are distributed. There would be more in certain streets than others, and they would thin out towards the centre. The distribution could be marked up on a street map. You might walk miles without seeing any, and then find several, near open spaces or watery places, as the birds need mud for their nests. A town with a river running through it would be more likely to have house martins than one without. In some places there are huge colonies of these birds.
FLORA AND FAUNA IN STREETS
While your eyes are on the ground, looking for bird droppings, you are sure to see weeds and plants at the foot of buildings, or between paving-stones, or in gutters. However good the street cleaning is, there are bound to be places where brushes can’t easily reach. There will be mosses of various kinds, fresh and green after rain. You will also find chickweed and shepherd’s purse, and possibly daisies, dandelions, groundsel, and sow thistles. A street flora would be interesting to compile. Occasionally very surprising plants are found. A paved yard has been known to produce hemp (hashish) because the owner cleaned birdcages there and sometimes hosed the yard, so that seeds were able to germinate.
Often a concrete path develops a crack, and it is interesting to see what happens there over a period. Before long there is dust, and soil, then odd plants, and if you scrape the soil away you will find insects such as springtails, leather jackets and wireworms. Other insects you will have to search for in towns include the privet hawk moth, the larvae of which feed on privet, so even dusty little front garden hedges are worth looking at, in spring and summer; the buff ermine moth, in Virginia creeper, and the yellow swallowtail moth in ivy. A possible place for plants and insects is round the foot of trees planted in streets. These tend to be very dry dusty areas, overshadowed by the trees themselves and with impoverished soil. But even here sampling will reveal a soil fauna. In country towns you might also see there traces of squirrels, at the foot of the trees, but not if these are isolated as squirrels travel from tree to tree. Occasionally you may even find owl pellets, little grey balls of indigestible matter – fur, bones, skin – regurgitated. These can be analysed and the contents identified, so you know what the owl has been eating. Sometimes litter boxes are placed at the foot of trees, and in this case you may find evidence of mice and rats. Ice-cream cartons with sugary liquid left in them may attract insects.
Empty tins, sometimes filling with rain water and then getting hot in the sun, also provide a new type of habitat, although not a long-lasting one. Foxes have been known to search dustbins, but only in the suburbs.
Trees planted in streets tend to be of the small ornamental kind, such as almond and cherry. But if conditions allow, naturalists would prefer to have larger trees, preferably those you would find in a native British woodland, such as oak, ash and elm. These, especially oak, tend to support a much richer variety of insect life than the others. The oak tree has been found to provide a habitat for as many as 284 insect species. Avenues of lime, or horse chestnut, are splendid, where there is room for them. The lime trees of Berlin are famous, and the chestnut trees of Paris. Two non-native species often seen in Britain are the London plane, good in street conditions, and the robinia, or false acacia, noticeable for its fresh green foliage. Any of these can be studied as habitats, but the trees themselves are worth study – which trees do best where, how they respond to the seasons and weather, and in what manner the leaves appear and unfold. Aerial views of towns often show a much larger tree population than one would expect from the ground. Comparison of some towns with others, or parts of a town with other parts, could yield interesting results, especially if correlated with bird surveys.
Trees in town are sometimes affected by air pollution. Gases from the exhaust pipes of cars may make it difficult for them to thrive. Evergreens, particularly firs and pine trees, are sensitive also to sulphur dioxide, given off in smoke from chimneys. Garden plants in towns may show blotching of the leaves from this cause. Dust and soot on leaves is damaging. In some areas (admittedly the worst industrial areas) two pounds of dirt fall on a square yard of ground every year. A white handkerchief hung on a washing line is a simple
T-NDC-D ‘J but effective indicator of visible atmospheric pollution. From every point of view, it is very desirable that air pollution should be reduced in towns. In December 1952, smog in London – that is, a combination of smoke and fog – is believed to have killed four thousand people. Another incident in 1957 killed many cattle at the Smithfield Show. If people and cows are killed, what effects may there be on other animals – domestic pets, and such forms of animal life as can exist in a city? Under the Glean Air Act, 1956, local councils can enforce smokeless zones, and where this has already been done, an enormous improvement has been brought about. If the air were cleaner, buildings would be free from the black coating so many of them now have. People, animals and vegetation could breathe more freely. Then if trees were planted wherever there is room – some big, some small, some specimen trees set round with flagstones or cobbles, some in small thickets of flowering shrubs, with daffodils and grass naturalized round them – all our cities could become garden cities.
CHURCHES AND CHURCHYARDS
Before we leave the street scene, there is another very special type of area there, of great interest for nature, although it is often neglected by naturalist and conservationist. This is the churches and churchyards of Britain. There are a great many of them – a city such as Norwich has more than thirty – and they are of exceptional importance because so many of them are right in the middle of built-up areas, where open space is so limited. Even in towns, most of our churchyards still possess magnificent trees. The evergreens are often particularly fine, especially the old yews, with their red and purple berries so beloved of thrushes and blackbirds. Holm oak is often found, and the Scots pine. To make these areas 4^ ktf* (ill* yA into bird sanctuaries would require only a few steps -such as planting more berrying shrubs, and others giving nesting places; leaving old trees and stumps; putting up bird boxes of different kinds, if old hollow trees are not available; planting thick hedges; providing water, and some winter feeding; creating a wild and undisturbed area for shelter and nesting. The Royal Society for the Protection of Birds has produced a leaflet suggesting methods of making school playgrounds into bird sanctuaries, but the quiet and age of churchyards make them even more suitable.
Even the gravestones are of great interest, especially when left standing and untouched. They provide a suitable place for the growth of lichens and mosses. In the built-up area of London, within a radius of Charing Cross, 165 species of lichen have been recorded (although only 71 have been seen since 1950). Most of them are on gravestones. The nitrogen they need for their growth seems to be supplied by birds which perch on the stones. These plants are of extraordinary interest, although their study is complicated and difficult. They are particularly useful today because they can act as indicator species for air pollution, being unable to grow in the areas of worst degradation, so that one biologist has said that in Britain we should aim at ‘air fit for lichens and rivers fit for trout’.
Again, because churches are usually much the oldest buildings in the areas round them, their walls may be of special interest. Ferns growing in them may include harts tongue, spleenwort, and brittle bladder ferns, and there may be algae, mosses, and liverworts. Other plants include pellitory of the wall, and the fascinating, pretty little ivy-leaved toadflax. Indeed many flowering plants are found in walls, such as wall rocket, stonecrop, valerian, and wallflowers. The walls of Ludlow Castle have been described as hanging gardens full of snapdragons, wallflowers, greater celandine, feverfew, wall rocket, red valerian, marjoram, and harebell. A survey of old walls in Middlesex showed that over 211 different species of wild plants were growing on them. If rebuilding or re-pointing of old walls is necessary, perhaps efforts could be made to see that some specimens of all species found are allowed to remain. Interesting studies can be made of the adaptation of plants to living on walls, the effect of broken walls and weathering, the differences between sunny and shady walls, and the effect of different materials on plant life. On damp walls there will be snails and slugs – in September snails begin to hide away for the winter, and they seal themselves into their shells with their own slime. You can often find them in wall crevices. Lizards, and mammals such as mice, stoats, or weasels, may also make their homes in cracks and hollows.
There are also many grassy areas to be found in our churchyards. Just as in gardens, these are more valuable for wild life if the grass is slightly longer than usual. Then voles may live there – food for tawny and little owls – and butterflies, and bumble bees. Molehills will be less of a nuisance in rough grass, so that there need be no attempt to drive moles away. Moreover, areas of uncut grass can be reserves of plants and plant associations that are becoming increasingly rare. In many parts of England permanent pasture – grass left un-ploughed, and unweeded – is being almost eliminated. In America, a search is having to be made in old graveyards for some of the native plants which have disappeared from cultivated prairies, and are now needed again to rejuvenate the land. In our own chuchyards, perhaps an acceptable policy for parts of them would be to cut the grass twice a year, first after the spring flowering in June, and then once only before the winter, and at neither time too short. More closely-grown paths can be made, as the contrast between short and rough grass can be very effective.
Finally, what about bats? These too require old buildings with ledges, crevices, and odd corners, the older the better. Church towers are one of their main habitats. They are often not liked, and inside a church they can cause dirt and damage. But if possible let us make a plea for them not to be destroyed. It would be a pity if they were all driven from their homes. It would be one more loss to chalk up in the history of disappearing species and vanishing animals.