56 invertebrate species were identified from the sediment at Culbin. There was little evidence of consistent and easily interpretable seasonal cycles for the main invertebrates, but several species tended to have higher abundance during the autumn or early winter. Annual production by invertebrates was 15-23 gAFDW.m-2.yr-1. Arenicola marina was the most important in terms of standing stock in the sediment, followed by the bivalve Cerastoderma edule. Production values of cockles were 1.4-3.4 gAFDW.m-2.yr-1. The most abundant epibenthic species were the brown shrimp Crangon crangon, the common goby Pomatoschistus microps and plaice Pleuronectes platessa, but other fish (e.g. sandeel Ammodytes tobianus, three-spined stickleback Gasterosteus aculeatus, fifteen-spined stickleback Spinachia spinachia, sea scorpion Myoxocephalus scorpio, pipefish Nerophis lumbriciformes, sand goby Pomatoschistus minutus, and flounder Plactichthys flesus), crab (e.g. shore crab Carcinus maenas and hermit crab Pagurus bernhardus ) and starfish (Asterias rubens) were also present. The most important prey were amphipods (mainly Bathyporeia) for the brown shrimp and common goby, and bivalves (siphons of adult individuals) for plaice. Despite the relatively high consumption rates manipulative field experiments showed that none of the predators had significant impact on invertebrate prey densities, although shorebirds had significant size effects on the prey, especially on the larger size classes of the bivalves C. edule and Macoma balthica. These results are in line with others found all around the world such as in the Ythan estuary, Scotland (e.g. Raffaelli & Hall, 1992, Anim. Ecol. 61: 551-560), USA (Wilson, 1994, J. Exp. Mar. Biol. Ecol., 196(1) : 15-25), and in New Zealand (Trush et al., 1994, Mar. Ecol. Prog. Ser., 107(3) : 211-222).
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:593104 |
| Date | January 1997 |
| Creators | Mendonca, Vanda Maria Domingos |
| Publisher | University of Aberdeen |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU106181 |
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