August, and lasts until September–October, being more intensive than the first.
Specimens migrating in summer-autumn have non-maturated gonads, while spring
migrants are already able to spawn. Starry sturgeons reach sexual maturity at
5 years (males) and 7 years (females). Spawning occurs in April and May, at
water temperatures of 8–15
C, having the same spawning grounds as the beluga
and Danube sturgeon. Fingerlings swim to the sea partly in July–August, partly in
September, forming agglomerations on the way. Some juveniles remain in the
Lower Danube until reaching 2 years of age. Large agglomerations of starry
sturgeon juveniles form off the Danube mouths. Fingerlings feed on chironomid,
tricopter and ephemerid larvae, crustaceans. As they grow, juveniles start feeding
on mollusks. Adults feed on mollusks, crustaceans and fish. Growth rhythm varies
from one river to another. Thus, the best growth is recorded by starry sturgeons
migrating in the Don River (1 year – 30 cm, 2 years – 60 cm, 4 years – 80 cm,
10 years – 120 cm) (Maximov and Zaharia 2010)
Fishery Starry sturgeons are caught with hooked lines, gillnets, pound nets and
bottom trawl. Currently, in Romania there is a ban on commercial starry sturgeon
fishery until 2020, confirmed by the annual Prohibition Orders (currently Order
no. 154/2016).
Commercial Importance The meat is tasty, but not comparable to Danube sturgeon. It is marketed fresh, refrigerated, frozen, salted, smoked or canned, and eggs
are eaten fresh or salted.
26.2 Experimental
The general assessment of the conservation status of the five target species is
derived from Annex E of the official reporting format. The results of assessing
the “Favourable Conservation Status ”(FCS) are given using the four available
categories: Favourable (FV), Unfavourable-Inadequate (U1), UnfavourableBad (U2) and Unknown (XX). For graphical representation, each class is colour
coded, green for Favourable, amber for Unfavourable-Inadequate’, red for
Unfavourable-Bad and grey for unknown. Assessments are qualified with a plus
or minus to indicate a trend (improving or declining) (Mihailescu et al. 2015).
The data and information on the geographical distribution of the marine fish
species were collected during various research surveys at sea, carried-out with
NIMRD’s “Steaua de Mare 1” rrsearch vessel, and from fishing points located
along the Romanian coast, during 2012–2014. The perimeters were selected so as to
be representative for each habitat type and species of interest. The monitoring
fishing was made during 2012–2014 by vessel (“Steaua de Mare 1”, equipped
with pelagic/demersal trawl gears – Fig. 26.6 left) and by pneumatic boat, for
specialized shad and sturgeon gillnet fishing (Fig. 26.6 right).
Four complex scientific surveys were performed, during which 52 pelagic/
demersal hauls were made, namely a fishing effort of 52 h of trawling and more
452
C.G. Nicolae et al.
Specimens migrating in summer-autumn have non-maturated gonads, while spring
migrants are already able to spawn. Starry sturgeons reach sexual maturity at
5 years (males) and 7 years (females). Spawning occurs in April and May, at
water temperatures of 8–15
C, having the same spawning grounds as the beluga
and Danube sturgeon. Fingerlings swim to the sea partly in July–August, partly in
September, forming agglomerations on the way. Some juveniles remain in the
Lower Danube until reaching 2 years of age. Large agglomerations of starry
sturgeon juveniles form off the Danube mouths. Fingerlings feed on chironomid,
tricopter and ephemerid larvae, crustaceans. As they grow, juveniles start feeding
on mollusks. Adults feed on mollusks, crustaceans and fish. Growth rhythm varies
from one river to another. Thus, the best growth is recorded by starry sturgeons
migrating in the Don River (1 year – 30 cm, 2 years – 60 cm, 4 years – 80 cm,
10 years – 120 cm) (Maximov and Zaharia 2010)
Fishery Starry sturgeons are caught with hooked lines, gillnets, pound nets and
bottom trawl. Currently, in Romania there is a ban on commercial starry sturgeon
fishery until 2020, confirmed by the annual Prohibition Orders (currently Order
no. 154/2016).
Commercial Importance The meat is tasty, but not comparable to Danube sturgeon. It is marketed fresh, refrigerated, frozen, salted, smoked or canned, and eggs
are eaten fresh or salted.
26.2 Experimental
The general assessment of the conservation status of the five target species is
derived from Annex E of the official reporting format. The results of assessing
the “Favourable Conservation Status ”(FCS) are given using the four available
categories: Favourable (FV), Unfavourable-Inadequate (U1), UnfavourableBad (U2) and Unknown (XX). For graphical representation, each class is colour
coded, green for Favourable, amber for Unfavourable-Inadequate’, red for
Unfavourable-Bad and grey for unknown. Assessments are qualified with a plus
or minus to indicate a trend (improving or declining) (Mihailescu et al. 2015).
The data and information on the geographical distribution of the marine fish
species were collected during various research surveys at sea, carried-out with
NIMRD’s “Steaua de Mare 1” rrsearch vessel, and from fishing points located
along the Romanian coast, during 2012–2014. The perimeters were selected so as to
be representative for each habitat type and species of interest. The monitoring
fishing was made during 2012–2014 by vessel (“Steaua de Mare 1”, equipped
with pelagic/demersal trawl gears – Fig. 26.6 left) and by pneumatic boat, for
specialized shad and sturgeon gillnet fishing (Fig. 26.6 right).
Four complex scientific surveys were performed, during which 52 pelagic/
demersal hauls were made, namely a fishing effort of 52 h of trawling and more
452
C.G. Nicolae et al.