46 research outputs found
Evidences of Multicomponent Structure of the Migratory Stock and Morphological Distinctions of Shads from the Genus Alosa (Clupeaformes, Alosiinae) of the Sea of Azov
Migratory stocks of shads passing through the Kerch strait during their seasonal migrations consist of three groups of specimens, that can be identified based on the number of gill rakers on the first arch. These are so called Kerch shad A. maeotica (50.2 %), Pontic shad A. immaculata (48.7 %) and Caspian shad A. caspia (1.1 %). This ratio of species in the region remains stable for the last 60 years. Populations of Kerch and Pontic shads have similar age structure and sex ratio with a shift toward females 52β54 %. Specimens of A. maeotica have greater linear size and weight than those of A. immacuta, that indicates higher growth rate of the former. Analysis of 26 body measurements shows definite differences between these shads in their absolute features, there are also some differences in the proportions of the head. Nevertheless, degree and reproducibility of interspecific differences during various periods of time, do not allow for the reliable discrimination of specimens of these species assumed by some researchers.ΠΠΈΠ³ΡΠ°ΡΠΈΠΎΠ½Π½ΡΠ΅ ΡΡΠ°Π΄Π° ΠΏΡΠ·Π°Π½ΠΊΠΎΠ²ΡΡ
ΡΠ΅Π»ΡΠ΄Π΅ΠΉ, ΠΏΡΠΎΡ
ΠΎΠ΄ΡΡΠΈΠ΅ Π² ΠΏΠ΅ΡΠΈΠΎΠ΄ ΡΠ΅Π·ΠΎΠ½Π½ΡΡ
ΠΌΠΈΠ³ΡΠ°ΡΠΈΠΉ ΡΠ΅ΡΠ΅Π· ΠΠ΅ΡΡΠ΅Π½ΡΠΊΠΈΠΉ ΠΏΡΠΎΠ»ΠΈΠ², ΡΠΎΡΡΠΎΡΡ ΠΈΠ· ΠΎΡΠΎΠ±Π΅ΠΉ ΡΡΡΡ
Π³ΡΡΠΏΠΏ, ΠΊΠΎΡΠΎΡΡΠ΅ ΠΌΠΎΠΆΠ½ΠΎ ΠΈΠ΄Π΅Π½ΡΠΈΡΠΈΡΠΈΡΠΎΠ²Π°ΡΡ ΠΏΠΎ ΡΠΈΡΠ»Ρ ΠΆΠ°Π±Π΅ΡΠ½ΡΡ
ΡΡΡΠΈΠ½ΠΎΠΊ Π½Π° 1-ΠΉ Π΄ΡΠ³Π΅. ΠΡΠΎ ΡΠ°ΠΊ Π½Π°Π·ΡΠ²Π°Π΅ΠΌΠ°Ρ ΠΊΠ΅ΡΡΠ΅Π½ΡΠΊΠ°Ρ ΡΠ΅Π»ΡΠ΄Ρ, A.?maeotica (50,2 %), ΡΠ΅ΡΠ½ΠΎΠΌΠΎΡΡΠΊΠΎ-Π°Π·ΠΎΠ²ΡΠΊΠ°Ρ ΡΠ΅Π»ΡΠ΄Ρ, A. immaculata (48,7 %), ΠΈ ΠΏΡΠ·Π°Π½ΠΎΠΊ, A. Ρaspia (1,1 %). Π’Π°ΠΊΠΎΠ΅ ΡΠΎΠΎΡΠ½ΠΎΡΠ΅Π½ΠΈΠ΅ ΠΌΠ΅ΠΆΠ΄Ρ ΡΡΠΈΠΌΠΈ Π²ΠΈΠ΄Π°ΠΌΠΈ Π² ΡΠ΅Π³ΠΈΠΎΠ½Π΅ ΠΎΡΡΠ°ΡΡΡΡ ΡΡΠ°Π±ΠΈΠ»ΡΠ½ΡΠΌ Π½Π° ΠΏΡΠΎΡΡΠΆΠ΅Π½ΠΈΠΈ ΠΏΠΎΡΠ»Π΅Π΄Π½ΠΈΡ
60 Π»Π΅Ρ. ΠΠΎΠΏΡΠ»ΡΡΠΈΠΈ ΠΊΠ΅ΡΡΠ΅Π½ΡΠΊΠΎΠΉ ΠΈ ΡΠ΅ΡΠ½ΠΎΠΌΠΎΡΡΠΊΠΎ-Π°Π·ΠΎΠ²ΡΠΊΠΎΠΉ ΡΠ΅Π»ΡΠ΄Π΅ΠΉ ΠΈΠΌΠ΅ΡΡ ΠΎΠ΄ΠΈΠ½Π°ΠΊΠΎΠ²ΡΡ Π²ΠΎΠ·ΡΠ°ΡΡΠ½ΡΡ ΡΡΡΡΠΊΡΡΡΡ ΠΈ ΡΠΎΠΎΡΠ½ΠΎΡΠ΅Π½ΠΈΠ΅ ΠΏΠΎΠ»ΠΎΠ², ΠΏΡΠΈ ΠΊΠΎΡΠΎΡΠΎΠΌ ΡΠ°ΠΌΠΊΠΈ ΡΠΎΡΡΠ°Π²Π»ΡΡΡ 52β54 %. ΠΡΠΎΠ±ΠΈ A. maeotica ΠΎΡΠ»ΠΈΡΠ°ΡΡΡΡ ΠΎΡ A. immaculata Π±ΠΎΠ»ΡΡΠΈΠΌΠΈ Π»ΠΈΠ½Π΅ΠΉΠ½ΡΠΌΠΈ ΡΠ°Π·ΠΌΠ΅ΡΠ°ΠΌΠΈ ΠΈ ΠΌΠ°ΡΡΠΎΠΉ, ΡΡΠΎ ΡΠ²ΠΈΠ΄Π΅ΡΠ΅Π»ΡΡΡΠ²ΡΠ΅Ρ ΠΎ Π±ΠΎΠ»Π΅Π΅ Π²ΡΡΠΎΠΊΠΎΠΌ ΡΠ΅ΠΌΠΏΠ΅ ΠΈΡ
ΡΠΎΡΡΠ°. ΠΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ 26 ΠΏΡΠΎΠΌΠ΅ΡΠΎΠ² ΡΠ΅Π»Π° ΠΏΠΎΠΊΠ°Π·ΡΠ²Π°Π΅Ρ ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΠ½Π½ΡΠ΅ ΡΠ°Π·Π»ΠΈΡΠΈΡ ΠΌΠ΅ΠΆΠ΄Ρ ΡΡΠΈΠΌΠΈ ΡΠ΅Π»ΡΠ΄ΡΠΌΠΈ ΠΏΠΎ Π°Π±ΡΠΎΠ»ΡΡΠ½ΡΠΌ ΠΏΡΠΈΠ·Π½Π°ΠΊΠ°ΠΌ, ΡΠ°ΠΊΠΆΠ΅ ΠΎΡΠΌΠ΅ΡΠ°ΡΡΡΡ Π½Π΅ΠΊΠΎΡΠΎΡΡΠ΅ ΡΠ°Π·Π»ΠΈΡΠΈΡ ΠΈ Π² ΠΏΡΠΎΠΏΠΎΡΡΠΈΡΡ
Π³ΠΎΠ»ΠΎΠ²Ρ. Π’Π΅ΠΌ Π½Π΅ ΠΌΠ΅Π½Π΅Π΅ ΠΌΠ°ΡΡΡΠ°Π± ΠΈ Π½ΠΈΠ·ΠΊΠ°Ρ Π²ΠΎΡΠΏΡΠΎΠΈΠ·Π²ΠΎΠ΄ΠΈΠΌΠΎΡΡΡ ΠΌΠ΅ΠΆΠ²ΠΈΠ΄ΠΎΠ²ΡΡ
ΡΠ°Π·Π»ΠΈΡΠΈΠΉ Π² ΡΠ°Π·Π½ΡΠ΅ ΠΏΠ΅ΡΠΈΠΎΠ΄Ρ Π½Π΅ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΡΡ Π½Π°Π΄Π΅ΠΆΠ½ΠΎ Π΄ΠΈΡΠΊΡΠΈΠΌΠΈΠ½ΠΈΡΠΎΠ²Π°ΡΡ ΠΎΡΠΎΠ±Π΅ΠΉ ΡΡΠΈΡ
ΠΏΡΠ΅Π΄ΠΏΠΎΠ»Π°Π³Π°Π΅ΠΌΡΡ
Π½Π΅ΠΊΠΎΡΠΎΡΡΠΌΠΈ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°ΡΠ΅Π»ΡΠΌΠΈ Π²ΠΈΠ΄ΠΎΠ²