English

41
GFCM:SAC13/2011/Dma2
belongs to viviparous fish; fingerlings are born at temperature more than 15°C. It distributes
with maximum density in Kalamitsky and Karkinitsky Bays in depth of 5 -30 m.
Grounds and fishing gears for target fishing of Rajiformes are the same as for picked dogfish.
By-catch of Rajiformes in trawls is inconsiderable and usually it releases to sea completely as
these fishes are of little demand at the domestic market. Till the early 1990s totally the whole
yield of Rajiformes were processed into the minced meat for feeding of poultry and other
domestic animals. After 1992 sales of minced flesh as feeds for animals slumped and
fishermen lost their interest for harvesting of Rajiformes. For recent years in Ukraine there
has been observed people's demand for Rajiformes as human food. In this connection their
fishing becomes to revive.
Till 1993, when the intensity of Rajiformes fisheries was high in the waters of Ukraine and
catches of thornback ray varied within the range 0.3-0.6 thousand tons, the stock of this
species was assessed by VPA method applying the software ANACO produced by FAO
(Shlyakhov, 1997; Shlyakhov and Lushnikov, 1995). For the subsequent years the intensity of
the coastal fisheries became so low that application of this method was incorrect. For some
years the stock of thornback ray was assessed by the trawl surveys data, however, due to the
under-recording of fishes in small depths these assessments were underestimated (Table 9).
Table 9: Commercial stock (thousand tons) of thornback ray in the Ukrainian Black Sea in
1992 1998.
Years
stock
VPA Trawl Survey
1992 2.6 1.1
1993 - -
1994 - 0.9
1995 - -
1996 - -
1997 - -
1998 - 1.0
Russia
Some data on the biology of dogfish and stingrays are given. All these fish have secondary
commercial importance because their annual catches are not big.
The dogfish squalus acanthias Linnaeus, 1758 is a small shark (it is up to 2 m long, weight is
up to 18 kg), inhabits the whole water column but prefers lower layers. Its main food items
are anchovy, kilka and other small fish, especially those which form accumulations. Its annual
catch has decreased during last decades, but they do not reflect the state of the stock. The
scientific trawl surveys undertaken every year show that the biomass of the dogfish in the
north-eastern part of the Black Sea is near 20 th.t and the total admissible catch (TAC) can be
estimated as 700 tons.
Rays. There are two species (the thornback ray Raja clavata Linnaeus 1758 and the stingray
Dasyatis pactinaka Linnaeus, 1758) in the Russian part of the Black Sea. They occupy
different ecological niches. Their stocks are about 800 t. Rays are usually caught together
with dogfish and flounders. TAC for ray cannot be more than 100 t.