The management options for a site can range from non- intervention, through minor alterations to maintain the site as it is, through larger-scale works over several years. The aims of management may be varied, including wildlife, public access, and farming and commercial interests. Water supply and drainage are regulated by outside agencies, and few sites are completely self contained. Most management involving waterways and wetlands requires consultation with various parties, and agreement over the varying aims and methods of achieving them. Climate and weather also play their part.

Management may require massive alterations to a site, with or without continuous and long-term follow-up, or it may consist of no more than fencing, screening, signposting or policing to protect the site from further interference. In every case, the aims, requirements and likely effects of the programme must be evaluated before it is begun.

Management aims may include the following:

  1. Influencing the ecological succession of a site or habitat in order to preserve or increase its wildlife value. Management may accelerate, maintain or retard the rate of succession.
  2. Conserving species endangered on a local, national or global level, by protecting existing habitat and where possible, creating more habitat.
  3. Protecting or creating areas of semi-natural habitat which support a range of wildlife. Within urban or intensively farmed land their importance for wildlife is increased if they are linked in a network to other areas of semi-natural habitat.
  4. Providing an amenity for passive or active recreation, or an educational resource.
  5. Improving or maintaining the health of an ecosystem. The interdependence of man and his natural environment is no longer being ignored by industries, agriculture, government agencies and decision makers. Although much remains to be done, huge sums are now being invested in systems which reduce or eliminate pollution, recycle waste and make better use of natural resources.

Site survey and analysis

It is important to find out as much as possible about the site before any decisions are made concerning its future management. It is difficult to assess its value for wildlife without making regular visits to the site over the course of at least a year. Contact the local office of Natural England (or equivalent) or the county wildlife trust for advice.

Survey questions

Surveys establish a baseline by which future changes can be measured and they provide information by which management can be made more precise as it progresses. Some survey techniques require specialised knowledge or equipment, but much can be learned from informed inspection of the site supplemented by a few simple tests.

Ideally, a site should be studied over the course of at least one year before management begins. Appearances at any one season may be deceptive since, for example, a site’s importance for flowering plants or overwintering wildfowl can be judged only at certain times of year. If fairly regular monitoring is not possible, the site should be inspected on three or four occasions during winter, late spring or early summer and autumn. If only one visit can be made, it should be in May or June when aquatic life is at its most active, although at this time the water level may be near its low point. When studying a site, don’t ignore local knowledge and opinion, particularly in the case of village ponds. The location of drains emptying into a pond, its changing water levels, past habitat quality and the impact of public pressure may often be more easily learned at the local pub than by the waterside!

The following questions are most important in the survey of waterways and wetlands sites:

  1. What is the water source? Ponds and lakes may exist due to natural drainage or seepage, or because they lie below the water table. They may depend on natural impermeable deposits, or may have been created by the use of an artificial lining. Ponds of a fairly regular shape, especially those in series with a noticeable drop between each, may be man-made hammer ponds, fish ponds, or watercress beds. Look for signs of a dam or weir wherever there is no other obvious reason for a pond’s existence.
    Streams, rivers and other linear water bodies may be fed by springs and seepage areas in addition to runoff. Watercourses running along rather than across the contours are man-made leats or canals.
  2. What is the water quality? Are there obvious signs of pollution or over-enrichment, such as oil slicks, suspended silt, algal blooms or dead fish ? Test the pH and sample the aquatic invertebrates.
    What affects water quality before it reaches the study area? Is the catchment intensively farmed or highly populated, producing drainage polluted by fertilisers or organic effluents? Forested catchments may supply sudden heavy loads of silt after clear-felling and nearby waterways may be deoxygenated when debris washed in sinks to the bottom to rot. Roadside ponds and streams are especially likely to be polluted since they often receive drainage water laden with dust, oil and road salt and are obvious targets for tipping.
  3. Does the water supply fluctuate with the prevailing weather, season or other factors? Are any such fluctuations harmful? Some watercourses and ponds are only seasonal, and have a particular flora and fauna associated with this seasonality. To try and prevent fluctuations may not only be difficult, but harmful to the ecosystem. Many seasonal pools are very stable ecosystems in the long term, providing valuable continuity of habitat. The summer drying out allows accumulated organic matter to oxidise, so preventing the pond from filling in. The growth of emergent and marginal plants is suppressed, while invertebrates, snails and other organisms survive in the damp mud. The unattractive state of a dried-out pond does not reflect its health as an ecosystem.
    In contrast, many wetlands rely on the manipulation of water level by flooding or ‘drawing down’ at various times throughout the year. This is necessary for some commercial reedbeds and grazing marshes. The value of wetlands for wading birds and other wildlife, and for water treatment, flood relief and coastal defence is now being realised, and many hectares of wetlands are now being managed by manipulation of water levels by sluices and pumps.
  4. What species of plants and animals are present on site? Do these include any rarities or species of particular interest, for which special provision should be made? Complete inventories of fauna and flora may not be feasible, but try to record as much information as possible within practical limitations of time and expertise. Consult English Nature, the local Wildlife Trust, Biological Records Centre or other organisations likely to have knowledge of the site.
  5. What are the human factors affecting the site? What is its present use and that of the surrounding area? How is this likely to affect the site in the future if present trends continue?

Is management required?

Once preliminary analysis and site surveys have been made, the following questions should be asked to clarify the management requirements:

  1. Is there a need for direct habitat management? Which plant species are dominant and do they need controlling? Are additional plantings needed? If so, which species would best adapt to the site without becoming too invasive? On very exposed sites, additional shelter may be beneficial. Do the banks, shoreline or bottom need modifying? Can this be done without causing secondary problems of spoil disposal, flooding or drainage?
  2. Is there a need to manage human uses of the site?
  3. How much is the site affected by surrounding habitats? Many species migrate between different water bodies and wetlands and may depend on this to find appropriate conditions during all seasons and phases of their life cycles. A site may lose much of its wildlife interest if surrounding land is improperly developed.
  4. Does the site have management priority over others? Does it really need management or can it go its own way for some time without losing value? Given the limited resources available for any management work, are there other sites more in need of immediate attention?
  5. Can less be attempted than is tempting? The sensitivity of some habitats to interference means that there may be a danger of trying too much too soon, with unexpected and unwanted repercussions. Management work should be phased, if possible, so that it can be checked early before making a commitment to the entire programme and so that unavoidable damage is localised and minimised. If a programme requires completion in order to be successful, it should be started only when there is certainty of carrying it through.
  6. How long will improvements due to the work remain? Will they wear off and conditions be the same or possibly worse as a result? Will the site require continuous management in order to maintain any improvements?

Choosing a method

If management work is judged necessary, each available work method should be evaluated by asking if it will:

  1. Achieve the desired results
  2. Minimise any habitat destruction
  3. Minimise any disturbance to wildlife due to interference at flowering or nesting seasons
  4. Involve risk to humans, non-target wildlife or agricultural crops and livestock
  5. Risk damage to equipment or physical installations on site
  6. Risk damage to other people’s property
  7. Require legal permission from government authorities or landowners
  8. Be possible given available labour
  9. Be possible given available funds for capital and operating costs

Introductions

New species of plants or animals may be introduced to a site for several reasons. These include to propagate species under threat elsewhere, to add diversity and interest to the site, to attract other species not yet present on a site or to stabilise an unbalanced ecosystem. The following safeguards are basic to ensure that harmful introductions can be avoided and all introductions are properly recorded.

  1. Draw up a list of species considered acceptable for introduction to the site. Indicate in which management areas within the site introduction is acceptable or unacceptable. For example, non-native trees and shrubs may be desirable for planting in areas of parkland character but not into existing copses or scrubland.
  2. Consult and invite the participation of the local county wildlife trust, the Biological Records Centre and Natural England (or their equivalents) in any large-scale introductions or those involving rare species.
  3. Notify either the local county wildlife trust or the Biological  Records  Centre  of  all  introductions.  In this way future scientific study of the area can take introduced species into account.

Animal management

Most conservation work on waterways and wetlands is directed at a general improvement of the habitat, often through management of the vegetation. However, the importance of animals in the ecosystem must not be overlooked, and the following sections describe techniques to encourage both diversity and speciality in the animal world.

Chapters