Mortality of the Bryozoan Pentapora fascialis in the Ligurian Sea (NW Mediterranean) after Disturbance

  • S. Cocito
  • S. Sgorbini


Pentapora fascialis (Pallas) population at Tino Island (Ligurian Sea, NW Mediterranean) underwent total and partial mortality. A severe sea-storm occurred in December 1993, caused near total mortality of the colonies at the shallow station (11 m depth): seven out of eight colonies were swept away. Total mortality was not size-selective and was independent of density. The deeper station (22 m depth) resulted unaffected by the sea-storm. Partial mortality, i.e. necrosis and loss of portions of colony, affected exclusively the largest colonies subjected to long lasting epibiosis and high sedimentation. Changes in the morphological characters (large cross-sectional area and poor adhesion to the substratum), wich occurred in the largest colonies, enhanced their susceptibility to dislodgement.


Great Barrier Reef Large Coloni Deep Station Shallow Station Partial Mortality 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Airoldi L, Fabiano M, Cinelli F (1996) Sediment deposition and movement over a turf assemblage in a shallow rocky coastal area of the Ligurian Sea. Mar Ecol Prog Ser 133: 241–251CrossRefGoogle Scholar
  2. Buss LW (1979) Bryozoan overgrowth interactions — the interdependence of competition for space and food. Nature 281: 475–477CrossRefGoogle Scholar
  3. Cheetham AH (1986) Branching, biomechanics and bryozoan evolution. Proc R Soc London 228, pp 151–171CrossRefGoogle Scholar
  4. Cheetham AH, Thomsen E (1981) Functional morphology of arborescent animals: strength and design of cheilostome bryozoan skeletons. Paleobiology 7: 355–383Google Scholar
  5. Cocito S, Ferdeghini F (1998) Marcatura con colorante ed etichettatura: due metodi per misurare la crescita in briozoi calcificati. In: Piccazzo M (ed) Atti XII Congr Assoc Ital Oceanol Lininol AIOL 2, pp 351–358Google Scholar
  6. Cocito S, Sgorbini S, Bianchi CN (1997) Zonation of a suspension-feeder assemblage on a temperate rocky shoal: the influence of water current and bottom topography. In: Hawkins LE, Hutchinson S (eds) The response of marine organisms to their Environments. Univ Southampton, UK, pp 183–192Google Scholar
  7. Cocito S, Ferdeghini F, Sgorbini S (1998a) Pentapora fascialis (Pallas) [Cheilostomata: Ascophora] colonisation of one sublittoral rocky site after sea-storm in the northwestern Mediterranean. In: Baden S, Pihl L, Rosemberg R, Strömberg, JO, Svane I, Tiselius P (eds) Recruitment, colonisation, and physical-chemical forcing in marine biological systems. Kluwer Acad Publ, Belgium, pp 59–66Google Scholar
  8. Cocito S, Sgorbini S, Bianchi CN (1998b) Aspects of the biology of the bryozoan Pentapora fascialis in the north-western Mediterranean. Mar Biol 131: 73–82CrossRefGoogle Scholar
  9. Connell JH, Keough MJ (1985) Disturbance and patchy dynamics of subtidal marine animals on hard substrata. In: Pickett STA, White PS (eds) The ecology of natural disturbance and patch dynamics. Academic Press, London, pp 125–151Google Scholar
  10. Denny MV, Daniel TR, Koehl MAR (1985) Mechanical limits to size in wave-swept organisms. Ecol Monogr 55: 69–102CrossRefGoogle Scholar
  11. Done TJ (1992) Effects of tropical cyclone waves on ecological and geomorphological structures on the Great Barrier Reef. Cont Shelf Res 12 (7/8): 859–872CrossRefGoogle Scholar
  12. Done TJ, Potts DC (1992) Influence of habitat and natural disturbance on contributions of massive Porites corals to reef communities. Mar Biol 114: 479–493CrossRefGoogle Scholar
  13. Frechette M, Aitken AE, Page L (1992) Interdependence of food and space limitation in benthic suspension feeder: consequence for self-thinning relationship. Mar Ecol Prog Ser 83: 55–62CrossRefGoogle Scholar
  14. Gautier YV (1962) Recherchés ecologiques sur lea bryozoaires chilostomes en Méditerranée occidentale. Rec Trav Stn Mar Endoume 38: 163–168Google Scholar
  15. Harvell CD, Caswell H, Simpson P (1990) Density effects in a colonial monoculture: experimental studies with a marine bryozoan (Membranipora membranacea L). Oecologia 95: 595–598Google Scholar
  16. Hayward PJ, Ryland JS (1979) British Aacophoran bryozoans. Kermack DM, Barnes RSK (eds) Synopses of the British Fauna. Academic Press, London, pp 1–312Google Scholar
  17. Hughes TP (1990) Recruitment limitation, mortality and population regulation in open system: a case study. Ecology 7 (1): 12–20CrossRefGoogle Scholar
  18. Jackson JBC (1979) Morphological strategies of sessile animals. In: Larwood G, Rosen BR (eds) Biology and systematics of colonial organisms. Academic Press, London, pp 499–555Google Scholar
  19. McKinney FK, Jackson JBC (1989) Erect growth: problems of breakage and flow. In: McKinney FK, Jackson JBC (eds) Bryozoan evolution. Univ Chicago Press, Chicago, pp 167–189Google Scholar
  20. Pickett STA, White PS (1985) Patch dynamics: a synthesis. In: Pickett STA, White PS (eds) The ecology of natural disturbance and patch dynamics. Academic Press, Orlando, pp 371–394Google Scholar
  21. Rogers CS (1993) Hurricanes and coral reefs: the intermediate hypothesis revisited. Coral Reefs 12: 127–137CrossRefGoogle Scholar
  22. Sale E, Garrabou J, Zabala M (1996) Effects of diver frequentation on Mediterranean sublittoral populations of the bryozoan Pentapora fascialis. Mar Biol 126: 451–459CrossRefGoogle Scholar
  23. Sgorbini S, Cocito S, Bianchi CN (1996) Underwater photography as a tool to monitor the population dynamics of a clonal organism. In: Albertelli G, De Maio A, Piccazzo M (eds) Atti XI Congr Assoc Ital Oceanol Limnol AIOL. Genova, pp 819–826Google Scholar
  24. Stebbing ARD (1971) Growth of Flustra foliacea (Bryozoa). Mar Biol 9: 267–273CrossRefGoogle Scholar
  25. Woodley JD, Chornesky EA, Clifford PA, Jackson JBC, Kaufman LS et al (1981) Hurricane Allen’s impact on Jamaican corals. Science 214 (4522): 749–755PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag Italia 2001

Authors and Affiliations

  • S. Cocito
    • 1
  • S. Sgorbini
    • 1
  1. 1.Istituto di Ricerca sulle AcqueENEALa SpeziaItaly

Personalised recommendations