Effects of the
dinoflagellate Alexandrium tamarense on early development of the
scallop Argopecten irradians concentricus
Tian Yan, Mingjiang Zhou, Meng Fu, Rencheng Yu,
Yunfeng Wang, Jun Li-2002
Aquaculture, 217(1-4): 167-178
Abstract:
The effects of Alexandrium tamarense (strain
ATHK) on early development of the bay scallop Argopecten irradians
concentricus were studied under laboratory conditions. The algal culture
was verified by HPLC to produce paralytic shellfish poisoning (PSP) at a
level of 37.48 fmol/cell. Survival of the scallop larvae was not affected
when they were grown with A. tamarense at concentrations of
500–10,000 cells/ml for 48 h. However, the activity of D-shape larvae was
inhibited after 48-h exposure to A. tamarense at the algal cell
density of 10,000 cells/ml. Scallop growth was inhibited significantly by A.
tamarense during a 14-day exposure starting at the eye-spot larval
stage. The size of juvenile scallops in the group of 10,000 cells/ml was
only about 32% of that of the controls, although no obvious effect of A.
tamarense was found on the rate of larval metamorphosis. All juvenile
scallops survived in algal concentrations of 600–2400 cells/ml, however,
attachment rates were significantly lower than control values after a 5-h
exposure to A. tamarense at concentrations >600 cells/ml, while
they were not obviously reduced after only 1 h of exposure. At
concentrations >600 cells/ml, the climbing ability of juveniles was
clearly reduced by exposure to A. tamarense after only 1 h. The
climbing rate and height were only 55% and 45%, respectively, of those of
the controls, when exposed to A. tamarense at a concentration of 600
cells/ml. The results indicated that A. tamarense blooms may have
detrimental impacts on shellfish at early life stages, therefore, special
attention should be paid to the toxic algal blooms in shellfish breeding
area.
(Institute of Oceanology, Chinese Academy of
Sciences, Qingdao 266071, PR China, e-mail: tianyan@ms.qdio.cn.cn)