Saltmarsh is a highly specialised and productive habitat supporting a flora which is adapted to cope with sea water. Within northeast England, saltmarsh is found on all the region’s estuaries. However the habitat is particularly concentrated in Northumberland. The regional resource is low by UK standards and is particularly poor in the Durham area. This is due to lack of sediment supply and suitable sites for the accumulation of sediments. Saltmarsh habitats are at risk from industrial development and are extremely hard to replace once they have been destroyed.
Protected species / habitat surveys in Hebburn, Northumberland
Site: Former shipyard in Hebburn, Northumberland
Protected species / habitats: bats, birds, invertebrates, reptiles and saltmarsh
UES undertook a Preliminary Ecological Appraisal (PEA) in June 2013 to establish baseline ecological data at a former shipyard in Hebburn, Northumberland. A large residential housing development is planned for the 3.2 hectare site.
The brownfield site has become a well-established and botanically diverse grassland, which has developed since the shipyard ceased in 1982. Other habitats on site include saltmarsh along the River Tyne, shingle beach, scrub and derelict buildings. The site contained habitats considered ecologically important which support a range of notably protected species. Brownfield land is listed under the Northumberland Biodiversity Action Plan with many associated Red Data and Nationally Scarce invertebrate species.
Following the PEA, specific botanical, bird, bat, reptile and invertebrate surveys were undertaken in 2013 and 2014 to gather more information regarding the potential impacts of the development.
The National Vegetation Classification (NVC) survey identified 5 different habitats on the land, from calcareous grassland to saltmarsh and intertidal mud flats. Over the 2 surveys 117 species of flowering plants were recorded, with some of local conservation concern. Badington’s orache (Atriplex prostrata), Sea couch (Agropyron pungens) and Annual sea blite (Suaeda maritima) are all listed as locally uncommon / scarce in south Northumberland. Although the site has no statutory protection the significant number of botanical species is of local interest.
Common bird census transects were carried out during the breeding bird season in 2013 and 2014. The surveys established a relatively diverse bird population on site with 49 species recorded over both years. Out of the birds found breeding on site, 6 species were classified species of principal importance for conservation of nature, under section 41 of the NERC Act 2006; Dunnock (Prunella modularis), Herring gull (Larus argentatus), House sparrow (Passer domesticus), Linnet (Carduelis cannabina), Song thrush (Turdus philomelos) and Starling (Sturnus vulgaris). The main impact identified would be the displacement of shoreline wading birds and seabirds associated with the saltmarsh and foreshore.
No roosting bats, reptiles or invertebrates of conservation concern were recorded on site, and therefore no further mitigation works are required in relation to these species.
UES have been commissioned to undertaken an ecological impact assessment (EcIA), which identifies the possible impacts to habitats and species arising as a result of implementing the construction and operational phases of the proposed residential development. The EcIA describes the methods used to assess the baseline conditions currently existing at the site and surroundings, the potential direct and indirect impacts of the development, the mitigation measures required to prevent, reduce or offset the impacts, and the residual impacts. The EcIA will be submitted with the planning application in 2016.