J. Caceresmartinez et A. Figueras, DISTRIBUTION AND ABUNDANCE OF MUSSEL (MYTILUS-GALLOPROVINCIALIS LMK) LARVAE AND POST-LARVAE IN THE RIA DE VIGO (NW SPAIN), Journal of experimental marine biology and ecology, 229(2), 1998, pp. 277-287
To compare the presence and abundance of mussel larvae and post-larvae
in offshore and inshore areas, plankton sampling was carried out over
18 months in four locations with different environmental characterist
ics in the Ria de Vigo (NW Spain). Larvae were more abundant in plankt
on samples (20 x 10(3) larvae m(-3)) taken near mussel culture rafts t
han in those from the intertidal mussel beds (1.6 x 10(3) larvae m(-3)
). Increments in the abundance of larvae were closely related with the
spawning periods of Mytilus galloprovincialis and with the rise in wa
ter temperature (spring to summer). Post-larvae were found in plankton
from the intertidal mussel beds, from late summer to early autumn, sp
ecially in the intertidal zone of exposed rocky shores (1.2 x 10(3) m(
-3)). Post-larvae were occasionally found in plankton samples taken ne
ar mussel rafts (< 10(2)/m(3)). in the intertidal mussel beds, post-la
rvae sizes reached 2.1 mm, while the maximum size found in the vicinit
y of mussel rafts was of 1 mm. The low number, and even absence, of po
st-larvae in plankton samples taken near the surface from localities a
way from the intertidal mussel bed could explain why previous studies
disregarded the existence of a planktonic dispersion of post-larvae in
this species. However, detailed studies on vertical distribution and
daily (tidal) fluctuation of mussel planktonic stages are needed. (C)
1998 Elsevier Science B.V. All rights reserved.