Project part-financed by the European Union (European Regional Development Fund)

The Interreg IVB North Sea Region Programme


Disclaimer:
The authors are solely responsible for the content of this report. Material included herein does not represent the opinion of the European Community, and the European Community is not responsible for any use that might be made of it.
Back to overview measures



Chowder Ness

Effectiveness according to development targets of measure

Habitat Area

The specific targets of the Chowder Ness Scheme were to create the following habitats:
  • 10.5ha of intertidal mudflat (and maintain this area in the long term, over the 10 year period);
  • 0.8ha of saltmarsh (and maintain this area in the long-term, over the 10 year period); and
  • 2.3ha of grassland (at least 50% of which should support natural plant communities comparable to local reference areas within 5 years of construction).
Another target with reference to increasing habitat area was to establish the planting of hawthorn in appropriate locations to the rear of the new sea defence and footpath.

Whilst saltmarsh establishment has been much slower and less extensive at Chowder Ness than at other schemes in the Humber , the area of coverage is continuing to expand five years post breach.

Habitat quality

Within 5 years of realignment, the target for habitat quality was for the mudflat that was created to be able to support an invertebrate assemblage of similar species, population abundance and biomass to local reference sites.
In particular, it was hoped to be able support the following key species:
  • Ragworm (Hediste diversicolor);
  • Bristle Worm (Pygospio elegans);
  • Mud Shrimp (Corophium volutator); and
  • Baltic tellin (Clam) (Macoma balthica).
It was also hoped that invertebrate quality would be maintained over the area of mudflat in the long-term.

Monitoring the success of habitat quality was proposed to be undertaken by including descriptions of the size distribution of individuals (adult/juvenile), tidal height and sediment properties, where samples were taken, in order to determine options for remedial action, if required.

It was also hoped that within 10 years of realignment, the saltmarsh created would show a similar zonation and species composition to existing adjacent saltmarsh, which locally include species such as common reed swamp, sea club rush, red fescue and sea plantain and that saltmarsh quality (species composition) would be maintained in the longer-term.

With regards to the intensity of the actual monitoring that has been undertaken at Chowder Ness, it was felt that little had been gained from the intensive invertebrate monitoring post breach. It was identified that invertebrate monitoring every year post inundation did not provide any more valuable information than would have been achieved at a less regular frequency. However, the monitoring has identified that species diversity has continued to rise at Chowder Ness over the five year monitoring period.

Bird Usage

One of the targets of the Chowder Ness scheme was for the creation of intertidal habitats with the ability to provide feeding habitat for in excess of 800 (peak mean over 5 years) feeding water birds with typical species in the following relative proportions:
  • 60% dunlin;
  • 20% black-tailed godwit;
  • 10% redshank; and
  • 10% other bird species.
Within ten years of realignment, it was hoped that the mudflat would be regularly used by approximately 607 overwintering waterfowl (peak) (166 average) based on the following species:
  • Golden plover;
  • Lapwing;
  • Dunlin;
  • Redshank;
  • Black tailed godwit;
  • Ringed plover;
  • Curlew; and
  • Shelduck.
This estimate was based on the assumption that waterfowl would use the realignment area pro rata to the adjacent bird count sector (ISE1). This usage should be maintained in the long-term, taking account of the natural variability through comparison with relevant WeBS data.

Another target was for the creation of terrestrial habitats to support a range of farmland bird species including linnet, goldfinch, blue tit, long-tailed tit, whitethroat, sedge warbler, reed warbler and reed bunting.

Breeding birds have been specifically monitored at Chowder Ness. The number of species of breeding bird observed at these sites has been consistent across the five year monitoring period, with a five year average of seven species (range 6 to 8). Total numbers observed have also remained consistent.

So far the site appears to be developing as expected as predicted in the EIA, and is broadly consistent with the conservation objectives defined as part of the consenting procedures.


Back to top

Important to know

Reports / Measures / Tools

Report: Management measures analysis and comparison