Fresh Water Habitats

This plan covers fresh water habitats such as rivers, drains, lakes and ponds. The River Hull is also included in the plan although it has strong saline influences. The importance of the habitats surrounding freshwater is also highlighted.

The mosaic of features found in rivers support a wide range of plants and animals. Marginal and bankside areas also support a variety of wild flowers such as Arrowhead (Sagittaria sagittifolia) and animals including Water Voles (Arvicola terrestris) and Water Shrews (Neomys fodiens). Rivers and other linear water bodies often provide a wildlife corridor link between fragmented habitats.

Ponds and lakes provide areas of standing fresh water that can be natural or man-made. Standing water provides a habitat for a very wide range of Britain's fresh water plants and animals, including some of our most endangered species. The increased number of ponds in gardens and school grounds has provided a valuable refuge for plants and animals including dragonflies, frogs and newts. They also provide the opportunity for people to experience wildlife close to their homes.

Current Status

The River Hull runs from north to south through the City. The River receives salt water from the Humber Estuary and is therefore brackish throughout its length in Hull. The degree of salinity and the depth of the River are dependent on the tides. The stretch of the River Hull within the City boundary is typically urban, yet it is still very important for wildlife. Numerous bird species are known to breed along the River Hull, including the Sedge Warbler (Acrocephalus schoenobaenus). There are small areas of reedbed along the edge of the river dominated by Common Reed (Phragmites australis), which are important for specialist species, such as the Reed Warbler (Acrocephalus scirpaceus) and Water Voles.

Hull was built upon marshland and relies on the many drains to keep the land dry. Many interesting plant species are found along the drains such as Arrowhead, Meadowsweet (Filipendula ulmaria) and Skullcap (Scutellaria galericulata). Both the major and minor land drains provide important habitats for birds. Kingfishers (Alcedo atthis) are regularly seen and there have been occasional sightings of Water Rail (Rallus aquaticus). Mute Swans (Cygnus olor) are often recorded on the Beverley and Barmston Drain and the Holderness Drain. Water Voles were once found in Holderness Drain, Foredyke Stream, and Old Main Drain but they have been very few sightings in recent years.

There are numerous ponds throughout the City, ranging from highly managed ornamental ponds to semi-natural ponds and temporary ponds that develop in hollows. Examples of ornamental ponds are found in Queens Gardens and Pearson Park. Many semi-natural ponds are built in gardens and school grounds and increasingly in the City's parks. There are several places in Hull where seasonal ponds develop, for example in the scrapes at North Carr, at Priory Park East and in the large hollow on former railway land at Calvert Lane.

Moorhens (Gallinula chloropus) breed in most of the Hull's parks. The presence of Great Crested Grebes (Podiceps cristatus) breeding in East Park is of local significance as there are few breeding sites in East Yorkshire. Gadwall (Anas strepera), Tufted Duck (Aythea fuligula) and Goosander (Mergus merganser) winter in East Park.

There are also several other features throughout Hull that provide freshwater habitats, including Bransholme Fishing Lake, the storm overflow lagoon at Bransholme Sewage Works and a sluice and borrow pit at the Arco site in the south west of the City.

Drains, ponds and lakes in the City area provide rich feeding grounds for insectivorous bat species including pipistrelles (Pipistrellus pipistrellus), Daubenton's bat (Myotis daubentonii) and Whiskered bats (Myotis mystacinus).

Current Factors Affecting the Habitat

• Pollution reduces the variety of plants and animals in all freshwater habitats. Run-off from agricultural land and built-up areas is the main source of pollutants. Pollutants include oil, road water run-off, pesticides, herbicides and fertilisers. Phosphate in sewage effluent and fertilisers can cause high levels of nutrients in freshwater and can lead to characteristic plants being replaced by blanket weed and other algae with following changes to animal communities.
  
  
• Introduction and escape of non-native species such as American Mink (Mustela vison), Signal Crayfish (Pacifastacus leniusculus) and Canadian Pondweed (Elodea canadensis), can have devastating effects on native plants and animals. Many non-native species out-compete or prey on native species and some may carry diseases that British species have no resistance to.
  
  
• All aquatic habitats are important for recreation but this can sometimes conflict with nature conservation. Discarded fishing tackle can be dangerous to many animals and birds and the use of lead weights in recent decades had dramatic effects on Mute Swan populations. Introduction of fish for angling and removal of predators can lead to the loss of natural fish populations and have an effect on plant and invertebrate communities. High numbers of wildfowl can reduce the value of ponds and lakes for other animals and plants. Boats can cause damage to plants, and dogs often disturb birds and mammals.
  
  
• Where rivers have been dredged, straightened or re-profiled (generally for drainage or navigation), stable beds which supported submerged and floating plants and other natural features have been lost, along with pools, undercut banks and other natural features which gave shelter to Otters, fish and birds.
  
  
• Succession from shallow water to dry land due to the build up of dead leaves and silt is a natural reason for the loss of pond habitat. Many of the ponds within Hull are in various stages of decline, generally becoming in-filled with reed and silted up. Without appropriate management these valuable wildlife resources will be lost. Land drainage and water abstraction can cause ponds to dry up. Ponds may also be lost to development and agriculture.
  
  
• The land surrounding a pond is an important part of the habitat. Reduction in the area of this 'buffer' zone' is the reason for ponds becoming less suitable to many animals, such as amphibians and dragonflies that breed in ponds but spend much of their adult life away from water.
  
  
• Over zealous management can result in the loss of fringe habitats and marginal zones. A number of the park ponds within Hull have been treated with herbicides to deal with invasive vegetation but these are often non-specific and kill all the plants rather than just those that are causing a problem.
  
  

Current Action

Legal Status

A number of organisations, including the Environment Agency (EA), Internal Drainage Boards (IDBs), water companies, and local authorities, are required by law to further conservation where it is in line with their management requirements. Legislation that deals with the functions and obligations of these organisations is set out in the Water Resources Act (1991) and the Land Drainage Act (1991). The EA also has legal responsibilities for pollution control.

Under the Wildlife and Countryside Act, (1981) the unlicensed release to the wild of non-resident alien animals, some established alien animals (including American Mink, and certain species of wildfowl, amphibia, fish and crayfish) and some plants e.g. Japanese Knotweed (Fallopia japonica), is prohibited.

Management, Research and Guidance

A number of agricultural support schemes are in place which aim to benefit watercourses. These include some Environmentally Sensitive Area recommendations, and the Countryside Stewardship Scheme.

The UK Biodiversity Steering Group (UKBSG) has produced a Habitat Statement for rivers and streams. The proposed conservation direction is to maintain and improve the quality, stateand structure of all UK rivers and streams and their associated floodplains, and restore degraded rivers and streams taking account of water quality and quantity, structure and hydraulic connection with the floodplain. A Habitat Statement has also been produced for standing open water.

A national Habitat Action Plan has been produced for reedbeds. The objectives of this plan are to identify and rehabilitate the priority areas of existing reedbed and maintain by active management. The plan also sets a target for the creation of 1200 hectares of new reedbed on land of low nature conservation interest by 2010. The UKBSG has also produced a Habitat Action Plan for eutrophic standing water.

The management of Hull's waterways varies but in general aims to maintain the flow of water through watercourses with stable banks. A scheme to enhance the wildlife and recreational value of a section of the Beverley and Barmston Drain was carried out in the 1990s. The steep-sided, linear drain was radically altered by major earthworks to create a series of meanders with shallow, marshy margins and gently sloping banks planted with native trees and shrubs. Two ox-bow lakes were also created. KuHCC has excavated a pond at Longhill Nature Reserve which, though outside the boundary, is owned by Hull City Council.

Action Plan Aims

1. To maintain and enhance reedbeds.
   
   
2. To monitor bird populations.
   
   
3. To monitor plant species.
   
   
4. To encourage creation of ponds.
   
   
5. To prevent loss of ponds through build up of silt.
   
   
6. To control invasive plant and animal species.
   
   
7. To provide advice on habitat management.
   
   
8. To improve habitats surrounding water.
   
   
9. To determine the distribution of Water Voles.
   
   
10. To ensure wildlife-friendly management practices.
    
    

What can we all do?

• Report any unusual animal sightings, especially birds, to the Partnership.
• Report any suspected pollution incidents to the Environment Agency.
• Report any sightings of injured/dead birds or other animals to the Environment Agency or Environmental Health at Hull City Council.

Links with other action plans

Rivers, drains and lakes are essential habitats for birds, including the Mute Swan. Patches of mud along the banks of lakes and rivers may be important for House Martins who use mud to construct their nests. Ponds and surrounding habitats are important for the Common Toad and Great Crested Newt. The marginal habitats are important for Reed Bunting, Water Voles, Harvest Mice and Dragonflies.

References

Andrews, J. (1995) Waterbodies. In: Managing Habitats for Conservation, ed. Sutherland, E.J. & Hill, D.A. pp. 121 - 149. Cambridge University Press, Cambridge.

English Nature (1997) Wildlife and Fresh Water: An Agenda for Sustainable Management. English Nature, Peterborough.

English Nature (1998) Managing Ponds for Wildlife. English Nature, Peterborough.

Holloway, S. (2001) BGEEP Biodiversity Project, North Carr, Bransholme. Bishop Burton College.

Holmes, N.T.H., Hanbury, R.G. (1995) Rivers, Canals and Dykes. In: Managing Habitats for Conservation, ed. Sutherland, E.J. & Hill, D.A. pp. 84 -121. Cambridge University Press, Cambridge.

Kingston upon Hull City Council (1997) State of the Environment. (Unpublished)

UK Biodiversity Steering Group/English Nature (1998) Tranche 2 Action Plans, Volume II: Terrestrial and Fresh Water Habitats. English Nature, Peterborough.

Wheater, C. P. (1999) Urban Environments. Routledge, London