The Role ofAlien Polychaetes along theAlexandria Coast, Egypt

Document Type: Original Research Paper

Authors

OceanographyDepartment, Faculty of science,Alexandria University, 21511Moharrem Bey, Alexandria, Egypt

Abstract

The alien polychaetes are widely distributed in the whole Mediterranean Sea as well as in the
Egyptian waters. The objective of this study is to highlight the distribution and abundance of the alien
polychaetes along the Alexandria coast, their contribution to the total polychaete community and the changes
they caused in the community structure. Through monthly sampling polychaetes were collected at four sites
of different ecological characteristics During June 2005 - May 2006 from hard substrates at 0.5-1m depth and
from soft bottom of the intertidal zone. Ten alien species were recorded from the study area, five of them
(Linopherus canariensis Langerhans, 1881, Loimia medusa Savigny in Lamarck 1818, Syllis schulzi Hartmann-
Schröder 1960, Phyllodoce longifrons Ben-Eliahu 1972 and Leodice antennata Savigny in Lamarck, 1818)were
found for the first time in the Egyptian waters. Six species were widely distributed in the study area demonstrating
considerable different count on both the spatial and temporal scales, with total count fluctuating between 10
- 18810 ind/m2 (individual/m2), constituting 14.3% - 45.5% of the total polychaetes and peaks occurring in
different times at the sampling sites. Syllis schulzi and Pseudoneries anomala were the major components,
accounting for 53.4 and 41.5% of the alien polychaetes, and of pronouncedly less contribution was Linopherus
canariensis (3.8%), in addition to occasional active contribution of Hydroides elegans and Loimia medusa,
which displayed at times up to 22% and 19% respectively at some sampling sites.

Keywords