FISH AT WALBERSWICK
69
INTERTIDAL AND SHALLOW SUBLITTORAL FISH AT WALBERSWICK, SUFFOLK J. R. ELLIS
J. R. Ellis
The Suffolk coastline comprises a range of habitats, including large sections of open coast that are generally comprised of pebbles, shingle and sand, and several estuaries (e.g. Rivers Stour, Orwell, Deben, Alde and Ore, and Blyth) with associated mudflats and salt marshes (Hiscock, 1998). Whilst there are a range of trawl surveys in coastal waters (Rogers et al., 1998; Ellis & Rogers, 1999) and some fish sampling from the intake screens at Sizewell (Henderson, 1989), the shallow water marine fauna for most parts of this dynamic coastline has not been subject to meaningful study (Hiscock, 1998). Indeed, the shingle beaches can be quite steeply shelving, which hampers shore-based sampling, and the high turbidity of the southern North Sea, especially in the surf zone, restricts visual surveys. In addition to the natural sand and gravel habitats along the open coast, there are also a range of artificial habitats, including groynes, piers and harbour walls (Fig. 1). These hard structures provide habitats for a range of marine taxa, including algae, barnacles, hydroids and bryozoans, which provide habitat for associated motile invertebrates, including small crabs, amphipods and shrimps. Such habitats can also support a range of fish species, as they provide shelter and food resources. The beach at Walberswick, on the south side of the estuary of the River Blyth, comprises a range of sediments, including swathes of sand as well as areas of more
Figure 1. Harbour at Walberswick showing main harbour wall and wooden pilings to the far right.
Trans. Suffolk Nat. Soc. 59 (2023)