Tayside Biodiversity Partnership Local Action Plan

Tayside Biodiversity - Tayside Biodiversity Action Plan - Urban - Built and Developed Environment

ECOLOGY AND MANAGEMENT
Urban and built up areas contain a surprisingly large number of native species. Pipistrelle bats Pipistrellus pipistrellus tend to use man-made structures such as modern houses and bridges for roosts, whereas Brown long-eared bats Plecotus
auritus favour older houses and buildings. House martins Delichon urbica and Swifts Apus apus rely heavily on man-made structures too – thus adding to the diversity of this, the most familiar and least natural of all our habitats.

Roadside verges and urban railways vary tremendously in the type of habitats they provide for many species. Although these habitats are largely grassland orientated, they are often associated with hedges, trees, bare soil and walls. For the most part these are the widespread and common species, but they can also include rare natives, together with a largeproportion of naturalised plants. As a linear habitat, urban road and path verges facilitate the distribution of newlycolonising species, as do railways, motorways, and trunk roads. Additional information will be included in a future Roads and Paths Habitat Action Plan.

Derelict or disturbed land tends to favour ‘pioneer species’. These include annuals such as Shepherd’s Purse Capsella bursa-pastoris and the Bittercresses Cardamine spp., through the various grasses and Willowherbs Epilobium spp. to the primary woodland species of Birch Betula pendula and Rowan Sorbus aucuparia. These rapidly establish themselves and equally rapidly spread and set seed. Often the short lifespan of these wildlife areas does not allow species to settle or for a wider mix of animals and plants to get established. The transitional nature of these sites means that management needs to reflect their future development potential, but their relative importance can be judged by their inclusion as community descriptions in the National Vegetation Classification. Although such sites increase the options for urban wildlife and can be beneficial in the short-term, they are no substitutes for properly managed greenspace.

Nationally, there has been a significant decrease in the number of farm and natural-edged garden ponds with the subsequent decline or loss of species such as Common frog Rana temporaria and Pillwort Pilularia globulifera. The Tayside region does, however, have a number of old mill ponds that have great potential as superb wildlife sites. Dundee’s Trottick Ponds Local Nature Reserve is one such example. Further information will be available in the forthcoming Ponds, Pools and Lochans Habitat Action Plan.

Historically, urban rivers and burns have been canalised with their banks invariably encased in concrete. This has impeded the spread of such native species as Water vole Arvicola terrestris and is a danger to birdlife who cannot access the water safely, nor utilise the banks as breeding sites. Where it is inappropriate to return the watercourse to its natural banking a variety of soft-engineering options can now be deployed which often have a visual benefit as well as being effective in flood prevention projects. Returning to natural banking or implementing the soft-engineering options can be extremely advantageous to wildlife with a very wide diversity of species directly benefiting. It should be noted, however, that excessive removal of debris can also have a very damaging effect on local urban waters and must be monitored carefully. The subject of urban watercourses will be more fully covered in the Urban Waters Habitat Action Plan.

The numbers of species in urban areas is greatly enhanced by non-native trees, shrubs and plants used in parks and gardens, together with the presence of many inadvertently introduced pests and weeds. Britain’s 14.5 million private gardens, however, represent the biggest potential natural areas in the country, but a high usage of chemicals and an overtidy attitude can have an equally adverse affect. There are many initiatives to encourage the planting of butterfly, bat and bird-friendly shrubs and plants and to generally make room for wildlife by providing a variety of nestboxes or suitable hibernation sites for hedgehogs and toads.

In high density housing areas, the smaller garden sizes can be offset by enhancing the surrounding public greenspace. In some cases elsewhere in Scotland tower block communities have taken over the responsibility of managing their surroundings by planting wildflower meadows, community orchards and areas of butterflyfriendly
shrubs which they then manage accordingly. It has been proven that other members of the community rarely damage such areas as so many people of all ages are involved in the decision-making and practical work. The same goes for enhancing school grounds.
Numerous projects are currently underway in which pupils, staff and parents are involved in creating school gardens, woodlands and orchards with linkages between
community and curriculum.

CURRENT FACTORS CAUSING LOSS OR DECLINE
DEVELOPMENT – new building (for housing, industrial or retail), including in-fill development within extensive garden ground, green belt and open space, can result in the fragmentation, disruption and occasional total destruction of wildlife habitats. Mature trees and established hedgerows, species-rich grasslands, rivers, burns and wetlands tend to be the most affected. Planning can take into consideration the wider implications of new developments ensuring that wildlife corridors are retained or introduced in new plans for industrial sites, retail parks and residential areas. Greenspace policies can be reconsidered to include community woodlands, wildflower areas, community orchards that preserve local heritage varieties of fruit, and stands of native trees.

Song Thrush
It has been proposed that the poor survival of
many song thrushes beyond their first year may
be caused by the ingestion of molluscicides.

New approach – better planning with positive measures to conserve the biodiversity within the newly developed site, protection of remaining wildlife sites, increase in the quality and quantity of greenspaces, identification of priority habitats, habitat creation, linking Tayside Biodiversity Action Plan projects to key sites – and setting up good practice demonstration sites. Priority should be afforded to development of brownfield
sites. This will be delivered through appropriate provision and understanding of biodiversity in Structure Plans, which set the framework for Local Plans. In addition, where there is a development requiring an Environmental Impact Assessment appropriate consideration will be given to the nature, scale and quality of biodiversity to be affected.

PUBLIC AND PRIVATE BUILDINGS – many species from Swifts and bats to masonry bees and wall-loving plants can be put at risk – birds are often prevented from nesting on buildings; bat colonies can be destroyed by inappropriate use of roof treatment chemicals or trapped when routine maintenance work takes place on buildings or on bridges.

New approach – guidance should be given to safeguard swifts, swallows and house martins, together with awareness-raising to protect all bat species. When renovation of buildings (including listed buildings) is undertaken, encouragement should be given for any re-pointing carried out to be done in lime mortar, where appropriate, so as not to exclude masonry bees. Where possible, retention of lime-loving plants such as ferns,
liverworts and mosses should also be considered.

Case Study
Dundee’s Green Space
Dundee City Council is unique in that it was the first local authority in the UK to adopt an “Urban Nature Conservation Subject Local Plan” (UNCSLP). This has raised the profile of nature conservation both within the Council and the city itself. The land use aspects of the UNCSLP will be rolled into the Review of the Dundee Local Plan to achieve better integration between development and local biodiversity.

The City Council has also produced an Open Space Strategy, which puts forward a broad vision for parks, play areas, open spaces and wildlife sites based on promoting a high quality of life and a sustainable urban environment. The Strategy proposes a system of accessible open spaces to meet a wide range of social, environmental and economics needs. An Urban Woodland Strategy will also give a long-term focus for enhancing existing woodland and planting new woods.

Case Study
A Swift Response to help Wildlife
Historic Scotland’s innovative restoration of Stanley Mills, Perthshire, incorporated nest spaces under the eaves of the roof for its already-resident colony of swifts.

The liaison between Historic Scotland, its project architect and the organisation Concern for Swifts (Scotland) led to a‘ Swifts in Historic Buildings’ Advice Note being written and made available.

Case Study
Brechin Nature Trail
The Brechin Nature Trail is a linear trail bordered by housing estates and a primary school and running adjacent to a railway line which is used by the Caledonian Steam Railway Association most Sundays.

The railway line and trail are bordered by a mixture of mature broadleaf trees that are encroaching on to the path and, in certain areas, on to the railway line. A partnership between the Caledonian Steam Railway Association and Angus Council’s Ranger Service and Arboricultural Officer will enable the trail to be extended.

An environmental audit of the area will be carried out and a management plan drawn up.

Improvements will range from selective thinning and pruning of existing trees to planting native trees and hedgerows to increase the site’s biodiversity. Fencing will also be included to improve health and safety and
to discourage informal access along the trail.

To ensure local ownership and pride in the project the adjacent primary school and local community groups will be encouraged to help plant trees and in constructing and siting bird and bat boxes.

TRANSPORT CORRIDORS - bypasses and road straightening/widening all cause direct physical damage to wildlife habitats with the additional increase of animal roadkills from high-speed traffic.

New approach – sympathetic management of existing road corridors, sensitive planning of routes, better habitat creation and enhancement along road corridors, better fencing, introduction of animal underpasses or overpasses and wildlife scaring devices.

POLLUTION from vehicle exhausts, herbicides, industrial leakage, oil and salt from the road surface to watercourses
has a direct impact on wildlife, including native trees, amphibians, invertebrates and birds.

New approach – Highlight good practice through awareness-raising/education projects, assessment of Local Authorities’ policies for salt-spreading during the winter and overall use of herbicides; encouragement for
improved technology of industrial processes and better pollution warning systems.

SEMI-NATURAL PLACES now support wildlife marginalised from intensively used farmland or development. Wastelands support rare solitary bees and invertebrates which rely on undisturbed soil and sandy outcrops. A variety of wildflower colonies will also occur which can include both invasive species and endangered plants such as orchids. Neglect of these sites will cause scrub invasion that can then mature into woodland. Whilst not always inappropriate, in some cases important populations of species needing more open ground, such as warblers and skylarks, can be lost.

New approach – Local Authorities and local communities need to highlight what semi-natural habitats they have, their proposed future use and their current management. Local Authorities need to assess resources available to ensure that urban wildlife sites are managed for biodiversity.

Case Study
Craigie Burn, Perth
The Craigie Burn is a small tributary of the River Tay. The flood prevention works which started in 1999 provided the opportunity to visually enhance the burn to the benefit of both local residents and
wildlife. Community involvement was an essential part of the project; a Volunteers Day attracted 20
people to directly play a part in habitat enhancement.

A partnership approach enabled soft engineering solutions to flood alleviation and at the same time
created an attractive wildlife habitat. The original wide rectangular channel was altered into a
narrower, more natural channel which will allow water to flow faster and cleaner during normal flows;
this will also attract various invertebrates, including Mayflies.

New banking was constructed in an undulating manner to give a more natural shape. The bank was stabilised with mesh netting and a mixture of topsoil and sub-soil incorporating a wildflower and grass mix. Seeds included Common Mallow, Great Willowherb and Lesser Burdock; all of these wild flowers will attract bees and butterflies.

The shelf was stabilised with coconut fibre placed in the water and secured with wooden stakes. Wetland plants such as Yellow flag, Meadowsweet and Sedges were planted. This type of habitat will attract a rich diversity of species and may well encourage the return of the long-absent Water Vole to a Perth burn.