numbers of sardine larvae caught in February.
April, May and June in coastal waters of the
southern Tyrrhenian Sea. Compared with plankton fluctuations, the peaks from February to May
parallel phyto- and zooplankton standing stocks.
Many phytoplankton species participate in the
spring bloom and Sardina pilehardus and
Gymnammodytes cicerellus in March may feed
on a wide size range of particles, comprising
eggs. nauplii and larval stages.
Dinoflagellates are the most important
group in the size range 20-50 mm (Ceratium
furea, Proracentrum micans. Ganiaulax polygramma) while Diatoms and Cyanophycae were
mainly represented by Rhizasolenia alata and
Nostoc planetonicum, respectively. In June, when
phytoplankton standing stock decrease, young
sardine was the only species occurring in the
ichthyoplankton and this species seems to feed
on the micro- and zooplankton communites.
Anchovies will feed successfully on dinoflagellates (Blaxter and Hunter 1982), and indeed
these motile phytoplankters seem to be the best
food for early larvae of Engraulis ringens (Walsh
et al. 1980).
Tintinnids and copepods are very important
components of spring-summer zooplankton.
The copepods Acartia margalefi and A. clausi,
Clausoealanus and Paraealanus copepodites (
Badalamenti et al. 1990; Zagami et al. 1996) and
the tintinnids Eutintinnus tubulosus, Metacylis
annuli/era, Helicastemella subulata (Fonda
Umani and Monti 1993, Sparla and Guglielmo
1994) are typical species of the coastal south
Tyrrhenian community.
When the spawning of sardine is completed,
anchovy eggs occur in large numbers (Vucetic,
1975). Engraulis encrasicholus larvae appeared in
July and reached higher densities from October
to December. In July, many fish larval species contribute to the ichthyoplankton community but in
August Lithagnathus mormyrus is the most abundant species. In summer and autumn, the diatoms
Nitzchia seriata and Rhizosalenia alata, the
dinoflagellates Proracentrum micans, Exuviaella
campressa and E. apora, and the ciliate
Strombidium may constitute the primary food for
anchovy larvae together with nauplii, copepodites and adults of the autumn zooplankton
community (the copepods Centrapages kroyeri
and Temora stylifera). The abundance of S. aurita
in January may be correlated with the diatoms
Thalassionema nitzsehoides, Rhizosolenia alata
Fish Larval Biomass and Plankton Production
147
and small copepods such as Clausocalanus furcatus. The newly hatched larvae are sustained by
remaining yolk, but while this is still being used
they begin feeding on diatoms. At the end of yolk
sac phase, there is a fairly abrupt transition in the
zooplankton, with larvaceans such as Oikopleura
being particularly important (Shelbourne 1953,
1957). Two short trophic pathways from primary
producers to fish larvae were indentified in the
Scotian Shelf, NW Atlantic (Mousseau et aL 1998):
the herbivorous food chain (large phytoplankton
=> calanoid copepods => fish larvae) and the
large-microphage shunt of the microbial food
web (small phytoplankton => appendicularians/pteropods => fish larvae).
These preliminary results demonstrate that
no temporal overlapping occurred among fish
larval species in the coastal waters of the southern Tyrrhenian Sea. Differences in the timing of
spawning and different larval development
imply that each species occupies each a characteristic trophic niche. The strong relationship
between fish larval abundance and phytomicro- and zooplankton cycles and species composition depends on many factors including
water temperature, egg size and amount of larval
yolk. Its is evident that r-strategist filter feeders
species, as sardine and anchovy, have a longer
spawning season, different from K-strategist
species such as S. aurita and L. mormyrus, that
occur over a much shorter time interval.
References
Badalamenti F, Zagami G, Manganaro A. Guglielmo L (1990)
Variazioni giornaliere della comunita zooplanctonica
literale nei pressi di Capo Peloro (Me): re1azioni con la fauna
ittica ed il regime idrodinamico. In: 53° Congr UZI Palermo
1-5 Ottobre 1990. pp 79-80
Bluter JHS, Hunter JR (1982) The biology of the clupeoid fishes.
Adv Mar Bio120; 1-223
Casavola N, Hajderi E, Marano G (1998) Relationship between the
density of Engraulis encrasicholus eggs and zooplanktonic
biomass in the southern Adriatic sea. BioI Mar Mediterr 5
{I}: 56-62
Cefali A, Potoschi A, Bruno R, Cavallaro G, Manganaro A, Costa F
(1997) The qualitative-quantitative analysis of the first juvenile stages of fish in Sicilian Tirrenic coast, and observations
about the reproductive periods of some species. BioI Mar
Mediterr 4 (I): 211-216
Cushing D (1967) The grouping of herring population. J Mar BioI
Ass UK 47 (1): 193-208
Cushing D (1969) The regulatory of the spawning season of some
fishes. I Cons Perm Int Expl Mer 33 (1): 81-82
Fonda Umani S, Monti M (1993) Distribuzione dei popolamenti
micmnectonici nelfarcipelago toscano. In: Universita di
April, May and June in coastal waters of the
southern Tyrrhenian Sea. Compared with plankton fluctuations, the peaks from February to May
parallel phyto- and zooplankton standing stocks.
Many phytoplankton species participate in the
spring bloom and Sardina pilehardus and
Gymnammodytes cicerellus in March may feed
on a wide size range of particles, comprising
eggs. nauplii and larval stages.
Dinoflagellates are the most important
group in the size range 20-50 mm (Ceratium
furea, Proracentrum micans. Ganiaulax polygramma) while Diatoms and Cyanophycae were
mainly represented by Rhizasolenia alata and
Nostoc planetonicum, respectively. In June, when
phytoplankton standing stock decrease, young
sardine was the only species occurring in the
ichthyoplankton and this species seems to feed
on the micro- and zooplankton communites.
Anchovies will feed successfully on dinoflagellates (Blaxter and Hunter 1982), and indeed
these motile phytoplankters seem to be the best
food for early larvae of Engraulis ringens (Walsh
et al. 1980).
Tintinnids and copepods are very important
components of spring-summer zooplankton.
The copepods Acartia margalefi and A. clausi,
Clausoealanus and Paraealanus copepodites (
Badalamenti et al. 1990; Zagami et al. 1996) and
the tintinnids Eutintinnus tubulosus, Metacylis
annuli/era, Helicastemella subulata (Fonda
Umani and Monti 1993, Sparla and Guglielmo
1994) are typical species of the coastal south
Tyrrhenian community.
When the spawning of sardine is completed,
anchovy eggs occur in large numbers (Vucetic,
1975). Engraulis encrasicholus larvae appeared in
July and reached higher densities from October
to December. In July, many fish larval species contribute to the ichthyoplankton community but in
August Lithagnathus mormyrus is the most abundant species. In summer and autumn, the diatoms
Nitzchia seriata and Rhizosalenia alata, the
dinoflagellates Proracentrum micans, Exuviaella
campressa and E. apora, and the ciliate
Strombidium may constitute the primary food for
anchovy larvae together with nauplii, copepodites and adults of the autumn zooplankton
community (the copepods Centrapages kroyeri
and Temora stylifera). The abundance of S. aurita
in January may be correlated with the diatoms
Thalassionema nitzsehoides, Rhizosolenia alata
Fish Larval Biomass and Plankton Production
147
and small copepods such as Clausocalanus furcatus. The newly hatched larvae are sustained by
remaining yolk, but while this is still being used
they begin feeding on diatoms. At the end of yolk
sac phase, there is a fairly abrupt transition in the
zooplankton, with larvaceans such as Oikopleura
being particularly important (Shelbourne 1953,
1957). Two short trophic pathways from primary
producers to fish larvae were indentified in the
Scotian Shelf, NW Atlantic (Mousseau et aL 1998):
the herbivorous food chain (large phytoplankton
=> calanoid copepods => fish larvae) and the
large-microphage shunt of the microbial food
web (small phytoplankton => appendicularians/pteropods => fish larvae).
These preliminary results demonstrate that
no temporal overlapping occurred among fish
larval species in the coastal waters of the southern Tyrrhenian Sea. Differences in the timing of
spawning and different larval development
imply that each species occupies each a characteristic trophic niche. The strong relationship
between fish larval abundance and phytomicro- and zooplankton cycles and species composition depends on many factors including
water temperature, egg size and amount of larval
yolk. Its is evident that r-strategist filter feeders
species, as sardine and anchovy, have a longer
spawning season, different from K-strategist
species such as S. aurita and L. mormyrus, that
occur over a much shorter time interval.
References
Badalamenti F, Zagami G, Manganaro A. Guglielmo L (1990)
Variazioni giornaliere della comunita zooplanctonica
literale nei pressi di Capo Peloro (Me): re1azioni con la fauna
ittica ed il regime idrodinamico. In: 53° Congr UZI Palermo
1-5 Ottobre 1990. pp 79-80
Bluter JHS, Hunter JR (1982) The biology of the clupeoid fishes.
Adv Mar Bio120; 1-223
Casavola N, Hajderi E, Marano G (1998) Relationship between the
density of Engraulis encrasicholus eggs and zooplanktonic
biomass in the southern Adriatic sea. BioI Mar Mediterr 5
{I}: 56-62
Cefali A, Potoschi A, Bruno R, Cavallaro G, Manganaro A, Costa F
(1997) The qualitative-quantitative analysis of the first juvenile stages of fish in Sicilian Tirrenic coast, and observations
about the reproductive periods of some species. BioI Mar
Mediterr 4 (I): 211-216
Cushing D (1967) The grouping of herring population. J Mar BioI
Ass UK 47 (1): 193-208
Cushing D (1969) The regulatory of the spawning season of some
fishes. I Cons Perm Int Expl Mer 33 (1): 81-82
Fonda Umani S, Monti M (1993) Distribuzione dei popolamenti
micmnectonici nelfarcipelago toscano. In: Universita di