Abstract
Coastal floating seaweed, originating from the intertidal, is colonized by various pelagic and subtidal benthic animals. At southwestern Iceland, common macrofaunal colonizers include the fish Cyclopterus lumpus L., the harpacticoid Parathalestris croni (Krøyer), the amphipods Calliopius laeviusculus (Krøyer), Gammarellus angulosus(Rathke), Dexamine thea Boeck and Ischyrocerus anguipes (Krøyer), and the isopod Idotea baltica Pallas. The colonization patterns of these species were studied by collecting samples from experimental and natural clumps of floating seaweed at approximately monthly intervals for ca. 18 months. The occurrence of colonizers was highly seasonal with maximum numbers between April and September. For most species, numbers were correlated with weight of clumps. The relationship of density (numbers/100 g algae) to weight of clump and distance from shore varied between species. The algal species composition of clumps appeared to influence some colonizers. Only juvenile C. lumpus were found, while all P. croni were sexually mature; juveniles predominated in other species. The different colonization patterns of the species can be explained partly by their biological traits. The clumps are vital for the breeding of P. croni and are used for feeding by C. lumpus fry. Other species possibly colonize floating algae accidentally, being programmed to seek attached vegetation. Floating clumps may, nevertheless, serve to disperse these species.
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References
Davenport, J. & E. I. S. Rees, 1993. Observations on neuston and floating weed patches in the Irish Sea. Estuar. coast. mar. Sci. 36: 395–411.
Druce, B. E. & M. J. Kingsford, 1995. An experimental investigation on the fishes associated with drifting objects in coastal waters of temperate Australia. Bull. mar. Sci. 57: 378–389.
Ingólfsson, A., 1995. Floating clumps of seaweed around Iceland: natural microcosms and means of dispersal for fauna. Mar. Biol. 122: 13–21.
Ingólfsson, A., 1998. Dynamics of macrofaunal communities of floating seaweed clumps off western Iceland: a study of patches on the surface of the sea. J. exp. mar. Biol. Ecol. 231: 119–137.
Ingólfsson, A. & E. Ólafsson, 1997. Vital role of drift algae in the life history of the pelagic harpacticoid Parathalestris croni in the northern North Atlantic. J. Plankton Res. 19: 15–27.
Kingsford, M. J., 1995. Drift algae: a contribution to near-shore habitat complexity in the pelagic environment and an attractant for fish. Mar. Ecol. Prog. Ser. 116: 297–301.
Lincoln, R. J., 1979. British Marine Amphipoda: Gammaridea. British Museum (Natural History), London: 658 pp.
Locke, A. & S. Corey, 1989. Amphipods, isopods and surface currents: a case for passive dispersal in the Bay of Fundy, Canada. J. Plankton Res. 11: 419–430.
Naylor, E., 1955. The ecological distribution of British species of Idotea (Isopoda). J. anim. Ecol. 24: 255–269.
Steele, D. H. & V. J. Steele, 1972. Some aspects of the biology of Calliopius laeviusculus (Krøyer)(Crustacea, Amphipoda) in the northwestern Atlantic. Can. J. Zool. 51: 723–728.
Steele, D. H. & V. J. Steele, 1973. Biology of Gammarellus angulosus (Crustacea, Amphipoda) in the Northwestern Atlantic. J. Fish. Res. Bd Canada 29: 1337–1340.
Tully, O. & P. Ó Ceidigh, 1986. The ecology of Idotea species (Isopoda) and Gammarus locusta (Amphipoda) on surface driftweed in Galway Bay (west of Ireland). J. mar. biol. Ass. U. K. 66: 931–942.
Tully, O. & P. Ó Ceidigh, 1987. Investigations of the plankton of the west cost of Ireland.-VIII. The neustonic phase and vertical migratory behaviour of the benthic peracaridea in Galway Bay. Proc. R. Ir. Acad. 87B: 43–64.
Vader, W., 1975. Het vlokreeften-geslacht Gammarellus in Nederland. De Levende Natuur 78: 111–114.
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Ingólfsson, A. Colonization of floating seaweed by pelagic and subtidal benthic animals in southwestern Iceland. Hydrobiologia 440, 181–189 (2000). https://doi.org/10.1023/A:1004119126869
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DOI: https://doi.org/10.1023/A:1004119126869