The objective of the present study was comparing some biological parameters including length, weight, age and sexuality of four species of genus ALOSA (A. saposchnikowii, A. sapia, A. kessleri and A. braschnikowi) in coastal zone of Mazandaran province of the Caspian Sea. Monthly random samples were collected during October 2014 and April 2015 (249 samples). The highest total length (27.65±4.32cm) and body weight (262.05±172.25g) belonged to A.braschnikowi. There was a significant correlation between total length and body weight among four species ofALOSA (P<0.001). Sex ratio (male: female) of four species were 1.35: 1, 1.28: 1, 1: 1.4 and 2.38: 1, in respect to above mentioned order. Only the sex ratio of A. saposchnikowii (2.38: 1) was significantly different from the expected 1: 1 ratio (P<0.001). Gonadosomatic Index (GSI) among four species of ALOSA was significantly different (P<0.05, F=4.04).Condition factor (CF) between four species of ALOSA showed a significant difference (P<0.05, F=4.26). The results showed environmental compatibility of A. braschnikowi was better than other species.

Present study is part of the identification and determination of Clupeidae (Genus ALOSA), in the southern area of the Caspian sea, off coastal waters in the Gillan Province during 1997_98. Total of 132 specimens were sampled. Morphometric_merestic parameters such as Gill rakers and ratio of eye to head length, etc. were used for the species identification purpose. Three species of Clupeidae, namely as: ALOSA brashnikovi (Borodin, 1904), A. kessleri (Grimm, 1887) and A. caspia (Eichwald, 1938). Results showed that A. brashnikovi had 22_49 with average of 36.6±5.41, A. caspia had 74_128 with average of 106.3±14.96, and A. kessleri had 49_73 with average of 58.5±10.5 percent Gill rakers. Results also indicated that the ratio of eye to head length for A. brashnikovi was between 15.91_21.88 with average of 18.53±1.03 percent for A. caspia was between 19.38_24.30 with average of 22.48±1.34 percent, and finally for A. kessleri was between 17.75_22.4 with average of 20.88±1.54 percent.

This survey is part of identification and determination of cIupeidae (Genus ALOSA), in southern Caspian Sea, Mazandaran and Golestan Province coastal waters during 1997-99. In this study, total of 336 fish samples were studied.The results showed that 4 species of cIupeidae, belong to: ALOSA brashnikowii (Borodin, 1904), A. caspia (Eichwald, 1983), A. saposchnikowii (Grimm, 1887) and A. kessieri (Grimm, 1887). For species identification two morphometric and morphomerestic factors were used.One of the important factors of morphometric is gill rakers and, A. braschnikowii had 20-40 with average of 30.93±6.11,A. caspia had 110-125 with average of 118.3±5.23,A . kessleri had 60-73 with average of 66.82±3.31and A. saposchnikowii had 20-48 with of average of 32.83±4.93percent gill rakers.Another important morphometric factors are percent ratio of eye diameter to total length. A. braschnikowii had 2.9-5.82 and average of 4.72±0.53percent, A. caspia had 5.73-7.46 and average of 6.21±0.52,A. saposchnikowii had 6-9.33 and average of 7.3±1.8 percent and finally, A. kessleri had 4.27 -6.48 and average of5.46±0.71percent.

Morphological studies are strong and instrumental for determining discreteness of the similar species and extensively used to identify differences between fish populations. A total of 216 specimens of ALOSA braschnikowi were randomly collected by beach seine from three fishing regions along the southern Caspian Sea coasts, including some regions of Miankaleh, Sari and Anzali, in the fishing season during 2018-2019. The extracted landmark-points (body shape data) were submitted to a generalized Procrustes analysis (GPA) to remove non- shape data in PAST software. In the present study, the size effect was removed successfully by procrustes action in PAST software. Principal component analysis (PCA) was performed to summarize the variation among the specimens as few dimensions as possible. As a complement to discriminant analysis, morphometric distances among the three localities were inferred to cluster analysis by adopting the Euclidean square distance as a measure of dissimilarity method as the clustering algorithm. The dendrogram derived from cluster analysis of Euclidean square distances showed that the three populations of A. braschnikowi were distinct from each other in terms of morphometric characters. The Wilks’ lambda tests of discriminant analysis indicated significant differences in morphometric characters of the three populations. The results of the present study demonstrated significant morphological differences between the three populations of A. braschnikowi. These differences in the three studied basins were mainly related to the characteristics of head and snout, body height, caudal peduncle,dorsal and anal fin base, which could be related to the hydraulic conditions and diet of the population.

Protein hydrolysates were produced from by-products (head, skin and viscera) of Caspian shad (ALOSA caspia), a major Clupeonella species in the Caspian Sea (2016). Hydrolysis was performed at three different times (15, 30 and 60 min), pH 8. 5, using commercial enzyme Alcalase and an enzyme to substrate ratio of (1 to 100) by-product at 50° C. The results indicated that, Protein recovery and degree of hydrolysis increased with increasing incubation time (60 min) (P<0. 05). Protein and lipid content of the hydrolysate were 78. 91%, and 0. 09%, respectively. The chemical score results showed that hydrolysates could fulfill human amino acid requirements. The protein efficiency ratio showed that hydrolysates had high nutritional value. According to high nutritional values, this can be used as protein source in fish feed.

Little is known about the biological characteristics of the Caspian shad, a commercial fish of Clupeidae family living in the Caspian Sea. Monthly random samples of the fish were collected at the Guilan province shores, southwest of the Caspian Sea from October 2001 to August 2003. Beach seine and gill nets were used in the sampling. Food items, condition factor and feeding changes with the change in the fish age, sex, station and season after invasion of Ctenophore Mnemiopsis leidyi to the Caspian Sea were studied. Samples (n= 262) had fork length 88-235 (156.7±31.9) mm, weighed 8-196 (51.92±32.7) grams and aged 1-6 (2.81±0.9) years old. The Vacuity Index (CV), Intestinal Relative Length (RLG) and Index of Fullness (IF) of the specimens were determined as 10.3%, 0.52±0.03 and 102.9±114.5, respectively. Phytoplankton (specially Rhizosolenia and Spirogyra) comprised 1.8%, zooplanktons (Ostracoda, Rhizopoda, Cladocera, Rotatoria, Copepoda, Cirripedia, Mysidacea, Bivalvia larvae and bony fishes larvae and eggs) comprised 98.0% and benthic fauna (Foraminifera, Porifera, Cumacea, Amphipoda, insects larvae and Palaemonidae) comprised 0.2% of the food abundance in the fish stomach and intestine.Among the food items, orders Copepoda (Acartia spp.) and Cirripedia (cypris Balanus) were the mainfood, comprising 83.1 and 12.9% of abundance, respectively. Acartia comprised 97.3, 80.4, 48.0 and 68.3% of the food in autumn, winter, spring and summer, respectively. For cypris Balanus, these figures were 2.0, 2.6, 41.9 and 25.3% for the seasons. No significant difference was found in food diversity and its abundance between male and female fish and between different ages. Generally, Acartia spp. and Balanus were dominant food items in the male and female fish and in different sized specimens. Acartia comprised about 97.0% of the food abundance in Talesh and Kiashahr areas and 65.7%in Anzali shores. The zooplanktons, as the main food item of the fish have suffered a major decrease due to the invasion of Mnemiopsis leidyi to the southern Caspian Sea. Hence, the index of fullness (IF) and growth of the fish shows a great reduction recently.

Genus ALOSA Linck, 1970 is widely distributed in the Caspian Sea but in Southern region of Caspian Sea identified species has not been reconsidered during past ten years.in order to study the population diversity ofALOSA species of Iranian waters of Caspian Sea, samples were collected over a period of one year from Chaboksar, Chaf and Kiashahr coastal water by beach seines and gill net. A total of 430 specimens were examined to identify four species namelyALOSA braschnikowi, ALOSA caspia, ALOSA kessleriand ALOSA saposchnikowi. A. braschnikowi was the most frequent species and ALOSA saposchnikowihad the lowest prevalence. A. braschnikowi and A. caspia had the highest and lowest mean fork length and weight, respectively. Sex survey showed that females were dominant in all species. The age rang was of 2 to 7 years old.

Caspian shad is a commercial fish of Clupeidae in Caspian Sea and biological characteristics of the fish has not been studied before. In the study, 180 specimens of the fish were collected from Southeast coasts of the Caspian Sea quarterly from November 2001 until June 2003 and beach seine and gill nets were used to catch them. Main purpose for the study was determining food items and feeding changes in fish age, sex, station and le season after invasion of ctenophore (Mnemiopsis leidyi) in Caspian Sea. The fish had Fork length, weight and age, 103-232 (158.8±24.4) mm, 16-130 (52.2±20.6) g and 2-5 (2.64±0.7) years old respectively , If and Vacuity Index, Intestinal Relative Length and Index of Fullness of them were determined 12.8%,0.51 ±0.02 and 168.7±192.1 respectively. The study showed ALOSA caspia caspia feeds on numerous food items and phytoplanktons (Rhizosolenia and Spirogyra) comprised about 4.5%, Zooplanktons (Foraminifera, Copepoda, Cirripedia, Bivalvia larvae etc.) comprised 95.0% benthic animals (such as Gammaridae) and bony fishes (larvae and eggs) about 0.5% of food abundance in its digestive tract. This study showed these zooplanktons are increase of Mnemiopsis leidyi in Caspian Sea, so Index of Fullness (IF) and growth the fish is reduced.