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  • Estimation of condition factor of Bengal Tongue Sole (Cynoglossus cynoglossus) in the Bay of ‎Bengal, Bangladesh.‎

    Tanjin, Sumaya; Rahman, Md. Ashekur; Uddin, Minhaz; Sarker, Biplob Kumer; Sarmin‎, Most. Shakila; Mawa‎, Zannatul; Rahman‎, Md. Ataur; Rahman, Obaidur; Samad, Md. Abdus; Habib, Kazi Ahsan; et al. (2021-12-31)
    The Bay of Bengal is rich with its biological diversity, which plays an important role in ‎the country's economic and social development. This study describes the condition ‎factor of Cynoglossus cynoglossus in the Bay of Bengal, Bangladesh. Samples were ‎collected from the Bay of Bengal during January to December 2020. Body weight (BW) ‎of fishes were taken by an electric balance with 0.01 g precision, and total length (TL) ‎was measured using a measuring board to the nearest 0.1 cm accuracy. The Fulton’s ‎condition factor was estimated by the equation: KF =100 × (BW/TL3). Total length and ‎body weight ranged from 10.0-38.7 cm (mean ± SD = 24.24 ± 6.30) and 9.1-280.6 g ‎‎(98.44 ± 57.79), respectively. The value of Fulton’s condition factor was observed as ‎‎0.6469 (SD = 0.1148), indicating unstable physiological condition of fish in Bay of ‎Bengal. The outcomes of this study will be helpful for sustainable management of C. cynoglossus in the Bay of Bengal and use as baseline information for further studies.‎
  • Re-discription of Calappa exanthematosa Alcock and Anderson, 1894 (Crustacea: Decapoda: ‎Calappidae) from the coastal waters of Pakistan.‎

    Osmani, Hamid Badar; Naz, Farah; Saher, Noor Us (2021-12-31)
    The box crab Calappa exanthematosa Alcock and Anderson, (1894) re-described ‎from the coastal waters of Pakistan. C. exanthematosa was collected as a bycatch during ‎the shrimp trawling. This species previously synonymised under C. japonica ‎Ortmann, (1892) from the Bay of Bengal, (type locality Japan), since 1937 to till date ‎‎(Galil, 1997; Spiridinov and Apel, 2007). Ng et al., (2011) re-described and illustrated the ‎C exanthematosa after comparison of freshly collected specimen of Calappa japonica ‎from the Gulf of Oman and India and revealed that the both species have resemblance ‎to each other, but few marked differences exist between both species. Current study re-‎described the morphological characteristic of C. exanthematosa from the coastal waters ‎of Pakistan.‎
  • Estimation of growth pattern and form factor of Torpedo scad Megalaspis cordyla (Linnaeus, ‎‎1758) in the Bay of Bengal, Bangladesh.‎

    Sarmin‎, Most. Shakila; Tanjin‎, Sumaya; Rahman‎, Md. Ashekur; Hasan, Md. Rabiul; Sabbir, Wasim; Asadujjaman, Md.; Mondol‎, Md. Rashedul Kabir; Habib‎, Kazi Ahsan; Hossain, Md. Yeamin (2021-12-31)
    The horse mackerel, Megalaspis cordyla is one of the commercially valuable fish species ‎in the Bay of Bengal. This study was defined the growth pattern and form factor (a3.0) of ‎M. cordyla in the Bay of Bengal. Total of 105 specimens were analyzed, caught from ‎the Bay of Bengal during January to December 2020. Total length (TL) was measured ‎by measuring board with 0.01 cm and body weight (BW) was taken by digital balance ‎with 0.01 g accuracy. The TL and BW varied between 16.8 to 41.0 cm and 67.15 to ‎‎544.0 g, respectively. The length-weight relationship (LWR) was significantly related (p < ‎‎0.0001), with r2 value 0.984. The evaluated allometric co-efficient (b) was 2.50 that ‎indicated negative allometric growth (< 3.0) in the Bay of Bengal. The estimated a3.0 was ‎‎0.0102 for M. cordyla in the Bay of Bengal. The assessed a3.0 was varied from 0.0069 to ‎‎0.0182 in worldwide waterbodies. The computed median (0.0102) and 95% confidence ‎limit (0.0099-0.0132) specified that M. cordyla poses the typical torpedo body shape ‎‎‘fusiform’. This study will provide information on growth pattern and form factor as well ‎as body shape alternation between geographic distributions which would be effective for ‎its stock assessment and management in the Bay of Bengal and else-where.‎
  • The first assessment on metal contamination in the critically endangered Sawback Angel Shark ‎‎(Squatina aculeata) from north-eastern Mediterranean.‎

    Turan, Funda; Yola‎, Mehmet Lütfi; Ergenler, Aysegul; Turan, Cemal (2021-12-31)
    A Sawback angel shark (Squatina aculeata) classified as “Critically Endangered” Global ‎Red List by the IUCN (2017) and CITES (2017) is one of the threated elasmobranch ‎groups and the increased pollution in the marine environment negatively impact angel ‎shark species. Despite this, limited information exists about the effects of toxic chemical ‎contamination in angel sharks. Therefore, present study was conducted to elucidate ‎heavy metal accumulation in Squatina aculeata captured from the Iskenderun Bay, ‎North-Eastern Mediterranean by electrochemical technique. Arsenic (As), Mercury (Hg), ‎Copper (Cu), Iron (Fe), Zinc (Zn) and Mangan (Mn) were found by electrochemical ‎analyzer. Among the gill and liver tissue samples of S. aculeata, Fe and Zn were detected ‎as highest concentrations followed by As, Hg, Mn and Cu; Among the muscle tissue of S. ‎aculeata, Fe and Zn were detected as highest followed by Hg, As, Mn and Cu. Average ‎total arsenic contents in S. aculeata was 7.5416±0.6548 μg g-1, which exceeded ‎maximum limit legalized for any kind of food. Similarly, Total mercury average content ‎in S. aculeata was 19.9942±1.6116 μg g -1, which exceeded the proposed limit value ‎which is 0.2-2 μg g-1, confirming that the consumption of S. aculeata is a high risk ‎threating the health of consumer. These results confirmed that the metal contamination ‎in North-Eastern Mediterranean area may pose a potential threat to the sustainability of ‎S. aculeata in marine ecosystem and the concentrations detected is the above the safety ‎limits for angel shark that should be taken into consideration regarding human ‎consumption.‎
  • Winners and losers: Post conflict biodiversity in the stressed ecosystem of Khor al-Zubair, Iraq

    Ali‎, Malik Hassan; Fawzi‎, Nadia Al-Mudaffar; Mohammed‎, Hanaa Hussein; Helmuth, Brian; Dwyer, Amanda M. (2021-12-31)
    A rapid assessment of biodiversity in the immediate wake of civil conflict and other ‎disasters is critical to inform recovery efforts. We report on the first surveys of aquatic ‎biodiversity in Khor Al-Zubair (KAZ) in southern Iraq, following the cessation of recent ‎violence in the region. This site is in the midst of ongoing environmental changes due to ‎climate change and reductions in water flow from the Tigris and Euphrates rivers, which ‎have led to increases in salinity in the KAZ. Monthly surveys of biodiversity were ‎conducted in 2017-2018 and compared to historical data from the site obtained from a ‎literature survey. Results indicate a loss of 80% of species richness, suggesting a ‎fundamental and potential catastrophic decline in species diversity resulting from largely ‎anthropogenic drivers.‎
  • Benthic assemblages for ecological evaluation of Lake Manzala, Mediterranean Sea, ‎Egypt.

    El Komi, Mohamed Mohamed (2021-06-30)
    Lake Manzalah one of the northern Nile Delta in Egypt is the largest lake, which lies ‎between the lakes Borollus and Bardaweel and connects to the Mediterranean Sea. It ‎has an area of current 250 thousand acres. It contains many islands particularly along ‎the south-western region forming of semi-enclosed basins and it is characterized by dense ‎submerged hydrophytes as Pomatogeton pectinals; Ceratophyllum demersum and ‎floating hyacinth Eichhornia crassipes. Seven major drains are loading directly in the ‎south to the west. Lake Manzalah-bottomed shallow (0.5-1m), brackish water (3-18‰ ‎and is suffering from the phenomenon of high nutrition (eutrophication) due to increased ‎rates of nutrients and organic matter. So some sources of wastes discharges such as ‎sewage and industrial waste and agricultural activity pour directly into the lake, ‎especially the southern region (Bahr El Baqar Drain). The study aims to study the ‎distribution of benthic organisms in the lake and knowledge of the relationship between ‎the types and aggregates benthic food ecosystem as the important food sources' for ‎some aquatic organisms, especially economic fish and crustaceans in study stations. ‎Bottom sediment samples were collected from 11 sites by grab sampler covering ‎different environments lake and from 4 drains consists mostly of organic materials ‎‎(sludge) is made up of waste sewage, industrial, agricultural waste plants, and calcareous ‎shells empty. Results indicate for examining configuration qualitative macro benthic ‎recording the 16 species of aquatic plants and invertebrates where empty calcareous ‎shells were more frequent. The abundance of macrobenthic organisms at different ‎sampling sites along Lake Manzala can be ranked as follows: Ostracoda (45.4%, 1010 ‎ind/m2) > submerged plants (12.9%, 287 tufts/m2) > Amphipoda (9.2%, 207 ind ∕m2) > ‎Polychaetes (7%, 110 ind ∕m2) Bivalves (5.9%, 132 ind ∕m2). The biomass of benthic ‎assemblages at different sampling sites can also be ranked as follows: at ST5 (18.1%, ‎‎4433 ind ∕m2) > St6 (11.3%, 2772 ind ∕m2) > ST8 (9.8%, 2405 ind ∕m2) > ST3 (9.2%, 2247) ‎‎> ST7 (8.7%, 2122 ind ∕m2). The biomass of benthic assemblages at different sampling ‎sites can also be ranked as follows: echinoderms (52%) > molluscs (27%) > crustaceans ‎‎(16%) > polychaetes (2%) > other groups (3%). Due to the increase of pollutants ‎extensively loaded into the drains are the possible factors having affecting the ‎constituents’ structures of benthos. Sites of sampling study were evenly spread (J’ > 0.8) ‎only at sites 6 and 8, moderate diversity (H’ > 1.00) was at most sites and show lower ‎value at sites 3 and 11 and 0 at site 1. The abiotic environmental effects in the lake are ‎general to those generally observed in other areas influenced by organic wastes, namely, ‎changes in the physic-chemical properties of the sediments and low oxygen ‎concentrations in the bottom water due to the decomposition of organic materials.‎
  • Growth and dispersal of razor clam Solen dactylus in the mudflats of Indus Delta, Sindh ‎Coast (Northern Arabian Sea)‎.

    Pirzado, A.A.; Mahar, M.A. (2021-06-30)
    The Razor clam Solen dactylus is being harvested for the last 10 years from mudflats in ‎creeks of district Thatta. The results of water and soil quality samples indicate the ‎suitability and support for growth, dispersal, production and reproduction of Solen ‎dactylus occurring in Indus delta eco-region. Water quality parameters of creeks ‎indicated the ranges of temperature of water and air 11 to 30 ℃ and 12 to 42℃, pH of ‎water between 8.2 to 8.9, alkalinity of water 267 to 480 mg/l, hardness of water 620 to ‎‎1150 mg/l, salinity of water from 22 to 33 ppt. The soil samples of mudflats indicated silt ‎clay 15 to 30%, sandy clay 20 to 40% and fine sand 30 to 40%. Spring, summer and ‎early winter seasons are suitable timing for harvesting razor clam. However, winter cold ‎and rainy seasons are not suitable for razor clam fishing. In winter, the animals become ‎inactive and remain in deep barrows and do not come to the surface. In period of rainfall ‎the razor clam holes were filled with fine silt thus large number of razor clam were ‎affected and even deaths may have been caused if mudflats were exposed at the time ‎of rain. ‎ The recorded mature size of razor clam ranged between length of 6 to 3.5 cm and weight ‎‎12 to 40 grams. A trained person dig-out 1.5 to 3 kg of razor clam in 12meter square in ‎‎20-40 minutes. Thus a person can exploit 10-20 kg of razor clam in a period of 3- 4 ‎hours, hence 15 - 20 kg of live razor clam can be harvested in a day or night by a person ‎when mudflat become exposed after tidal action. Coastal communities inhabiting creek ‎areas are engaged in its harvesting using traditional techniques of using salt and probing ‎with thin sticks and hauling razor clams from burrow during low tides when mudflats ‎become exposed. It is concluded that Razor clam is an ecologically important group of ‎marine organism, lives in mudflats and creek systems. Although the razor clams are not ‎locally consumed by native people of Pakistan but it is a fishery having export value ‎which foreign exchange earned by exporting it to South East Asian countries.‎
  • Investigation of Haemogregarina in Sawrow fish (Trachurus mediterraneus) in Zliten ‎coastal area, Libya

    Ahmed, Samia H.; Yousif, Ramzy A.; Eldehidya, Radwan; Elaakary, Salim (2021-06-30)
    This study was conducted to estimate the prevalence, mean abundance, and mean ‎intensity of Haemogregarina infection on Sawrow fish (Trachurus mediterraneus) from ‎Zliten coast, Libya. A total of 12 specimens of Sawrow fish species were collected ‎randomly, the length (19.23 ± 0.72cm) and the weight (110.25 ± 7.88 g). The fish were ‎transported immediately alive to the laboratory in the Department of Fish Biology and ‎Fish Culture, College of Marine Resources, Asmarya University, where they were ‎maintained alive in well aerated glass aquaria (1x2x4 m). The gills, fins, and skin were ‎examined for ectoparasitic protozoa using a light microscope. The results showed ‎positive effect of haemogregarina in the Sawrow. Blood recorded the highest prevalence ‎and abundance among all the other organs in Sawrow fish followed by kideny, liver and ‎spleen respectively. The results provide a significant difference at (p<0.01), and the ‎results were discussed with other studies in the haemogregarinidae.‎
  • Form factor of Japanese threadfin bream, Nemipterus japonicus (Bloch, 1791).‎

    Rahman, Md. Ashekur; Ohtomi, Jun (2021-06-30)
    Japanese threadfin bream, Nemipterus japonicus is a large-scale commercial fish found ‎in the Pacific and Indian Ocean. Form factor (a3.0) is used widely for comparison of the ‎fish body shape between geographic locations. The present study was aimed to estimate ‎the form factor of N. Japonicus from available literature based on empirical model. ‎Assessed a3.0 ranged from 0.0035 to 0.0270. The median (0.0143) and 95% confidence ‎limit (0.0130-0.0168) indicated that N. Japonicas poses the typical torpedo body shape ‎‎‘fusiform’. Findings on the form factor of N. japonicus will be effective for perceiving ‎further body shape alteration between geographic distributions.‎
  • Authentication and traceability of pufferfish species using DNA sequencing.

    Doğdu ‎, Servet Ahmet; Turan, Cemal (2021-06-30)
    Pufferfish is known a powerful toxin in its skin and organs called Tetrodotoxin. ‎Validation of food authenticity is usually based on the analysis of proteins or DNA ‎sequences. DNA based methods are more effective and can also be applied to different ‎food matrices. DNA barcoding is a rapidly rising global initiative in which species are ‎characterized using mtDNA sequences. This is based on the premise that species are ‎generally well delineated by a species-specific sequence. In this study, we revealed DNA ‎barcoding of three pufferfish species Lagocephalus sceleratus, Sphoeroides pachygaster ‎and Torquigener flavimaculosus using the mtDNA cytochrome b gene region. There were ‎‎122 variables and 266 conservative nucleotides of which 110 were parsimony ‎informative over 388 bp sequences. The mean nucleotides composition was found as ‎‎%28.0 thymine (T), %30.7 cytosine (C), %24.8 adenine (A) and %16.6 guanine (G). ‎Twelve haplotypes were found out of 18 sequences and mean haplotype diversity was ‎observed at 0.9346. This study has strongly authenticated and traceability the efficacy ‎of Cty b in identifying L. sceleratus, S. pachygaster and T. flavimaculosus species with ‎designated barcodes. This is the recorded of L. sceleratus, S. pachygaster and T. ‎flavimaculosus cytochrome b gene sequence from the eastern Mediterranean coast of ‎Turkey.‎
  • Sex ratios of Metapenaeus kutchensis George, George and Rao, 1963 and Parapenaeopsis sculptilis (Heller, 1862) in the Gulf of Kachchh, Western India.

    Pravez, Rishad; Krishnan, Smita; Mansuri, A.P. (1992-06-30)
    Sex ratio data of two species of penaeid prawns Metapenaeus kutchensis George, George and Rao, ‎‎1963 and Parapenaeopsis sculptilis (Heller, 1862), occurring in the Gulf of Kachchh, were ‎statistically analyzed. A preponderance of females was observed in both the species and the ratio ‎of male to female for both years combined for M. kutchensis and P. sculptilis was found to be ‎‎1:1.5 and 1:2.7, respectively. Chi-square analysis revealed significant difference in the sex ratios of ‎the two species.‎
  • Re-description of Lupocyclus philippinensis (Crustacea: Decapoda: Brachyura: ‎Portunidae) Semper in Nauck, 1880 from the coastal waters of Karachi, Pakistan.‎

    Naz, Farah; Saher, Noor Us; Osmani, Hamid Badar (2019-12-31)
    A specimen of the Lupocyclus philippinensis Semper in Nauck, 1880 commonly known ‎as scissor swimming crab, was recently found in by catch of shrimp trawling and ‎included as part of continuous taxonomic studies on crabs found in the coastal waters of ‎Pakistan. The discovery is significant because it found after a long time. Redescription of ‎L. philippinensis following the discovery of a female caught at Karachi fish harbor, ‎Pakistan by Leene and Buitendijk (1952).‎
  • Community structure and seasonal distribution of intertidal macrofauna from two rocky ‎shores of Karachi coast.

    Ali, Qadeer Mohammad; Ghory‎, Farhana S.; Ahmed, Quratulan; Siddique, Saima; Mubarak, Shumaila; Memon, Sehrish (2019-12-31)
    Rocky shores are considered heterogeneous environments due to their composition and ‎structure. Therefore, they support numerous habitats for flora and fauna. Organisms ‎found on rocky shores are facing intense physicochemical conditions during tidal ‎changes from upper to lower intertidal zones. Total (N=1888) specimens were collected ‎on seasonal basis from intertidal zone during low tide from two rocky sites of Karachi ‎coast, Buleji and Sunehri during January 2017 to December 2017. The highest number ‎of individuals (N=1041), were recorded from Buleji than Sunehri (N= 847). The seasonal ‎abundance in Mollusca were measured as (36.84%), (63.67%), (25.08) and (40.38%) ‎from Buleji while from Sunehri (45.16 %), (46.01%), (48.65) and (42.79 %) during pre-‎monsoon, south-west monsoon, post monsoon and north-east monsoon season ‎respectively. Group Arthropoda, Mollusca and Echinodermata were shows the highest ‎abundance of the species at both sites as compare to other groups. The highest diversity ‎index from Sunehri (H'=0.64) was measured in north-east monsoon season meanwhile, ‎‎(H'=0.61) was measured in post monsoon season from Buleji coast. Evenness index ‎‎(J'=0.25) in pre-monsoon season from Buleji and (J'=0.28) in south-west monsoon season ‎from Sunehri coast . Season shows the great abundance of species as compare to other ‎seasons. No significant correlation was observed in between seasons, water temperature ‎and salinity with macrofauna groups at both sites. ‎
  • Empirical use of growth, mortality and temperature data for anchovy.

    Bilgin, Sabri (2019-12-31)
    To estimate the empirical relationships in anchovy, the instantaneous natural mortality ‎rate (M) calculated from von Bertalanffy Growth Function (VBGF) parameters, ‎maximum total length (Lmax) and sea surface temperature (T,°C) were reviewed in the ‎Black Sea. Empirical equations were presented for evaluation of M data in their ‎relationships to VBGF parameters, T and Lmax. Based on biological consideration and ‎regressional definition, it was recommended to use following formulas for estimating of ‎natural mortality rate of small pelagic fish such as anchovy. M = 0.3237 + 1.3174*(K) - ‎‎0.0036*(L∞) - 0.0117*(T); M = 0.2639 + 1.3676*(K) - 0.0003*(Lmax) - 0.0124*(T).‎
  • Artificial neural networks model biometric features of marine fish sand smelt.‎

    Benzer, Semra; Benzer, Recep (2019-12-31)
    In this study was investigated some biometric properties of the sand smelt with ANN’s, ‎Atherina boyeri Risso, 1810, population in Yamula Dam Lake. Twenty-three ‎morphometric characters of samples were measured. The total length of individuals ‎which were caught between 6.40 and 10.20 cm, and their weight (W) were ranged ‎between 1.50 and 7.31 g. The effect of Artificial Neural Networks was investigated in ‎predicting the statistical of fishery industry. The present study provides the first ‎information on the biometric properties of Atherina boyeri in Yamula Dam Lake by ‎Artificial Neural Networks.‎
  • Community structure and seasonal distribution of intertidal macrofauna from two rocky shores of Karachi coast

    Ali, Qadeer Mohammad; Ghory, Farhana S.; Ahmed, Quratulan; Siddique, Saima; Mubarak, Shumaila; Memon, Sehrish (2019)
    Rocky shores are considered heterogeneous environments due to their composition and structure. Therefore, they support numerous habitats for flora and fauna. Organisms found on rocky shores are facing intense physicochemical conditions during tidal changes from upper to lower intertidal zones. Total (N=1888) specimens were collected on seasonal basis from intertidal zone during low tide from two rocky sites of Karachi coast, Buleji and Sunehri during January 2017 to December 2017. The highest number of individuals (N=1041), were recorded from Buleji than Sunehri (N= 847). The seasonal abundance in Mollusca were measured as (36.84%), (63.67%), (25.08) and (40.38%) from Buleji while from Sunehri (45.16 %), (46.01%), (48.65) and (42.79 %) during pre-monsoon, south-west monsoon, post monsoon and north-east monsoon season respectively. Group Arthropoda, Mollusca and Echinodermata were shows the highest abundance of the species at both sites as compare to other groups. The highest diversity index from Sunehri (H'=0.64) was measured in north-east monsoon season meanwhile, (H'=0.61) was measured in post monsoon season from Buleji coast. Evenness index (J'=0.25) in pre-monsoon season from Buleji and (J'=0.28) in south-west monsoon season from Sunehri coast. Season shows the great abundance of species as compare to other seasons. No significant correlation was observed in between seasons, water temperature and salinity with macrofauna groups at both sites.
  • Artificial neural networks model biometric features of marine fish sand smelt

    Benzer, Semra; Benzer, Recep (2019)
    In this study was investigated some biometric properties of the sand smelt with ANN’s, Atherina boyeri Risso, 1810, population in Yamula Dam Lake. Twenty-three morphometric characters of samples were measured. The total length of individuals which were caught between 6.40 and 10.20 cm, and their weight (W) were ranged between 1.50 and 7.31 g. The effect of Artificial Neural Networks was investigated in predicting the statistical of fishery industry. The present study provides the first information on the biometric properties of Atherina boyeri in Yamula Dam Lake by Artificial Neural Networks.
  • Empirical use of growth, mortality and temperature data for anchovy

    Bilgin, Sabri (2019)
    To estimate the empirical relationships in anchovy, the instantaneous natural mortality rate (M) calculated from von Bertalanffy Growth Function (VBGF) parameters, maximum total length (Lmax) and sea surface temperature (T,°C) were reviewed in the Black Sea. Empirical equations were presented for evaluation of M data in their relationships to VBGF parameters, T and Lmax. Based on biological consideration and regressional definition, it was recommended to use following formulas for estimating of natural mortality rate of small pelagic fish such as anchovy. M = 0.3237 + 1.3174*(K) - 0.0036*(L∞) - 0.0117*(T); M = 0.2639 + 1.3676*(K) - 0.0003*(Lmax) - 0.0124*(T).
  • Re-description of Lupocyclus philippinensis (Crustacea: Decapoda: Brachyura: Portunidae) Semper in Nauck, 1880 from the coastal waters of Karachi, Pakistan

    Osmani, Hamid Badar; Naz, Farah; Saher, Noor Us (2019)
    A specimen of the Lupocyclus philippinensis Semper in Nauck, 1880 commonly known as scissor swimming crab, was recently found in by catch of shrimp trawling and included as part of continuous taxonomic studies on crabs found in the coastal waters of Pakistan. The discovery is significant because it found after a long time. Redescription of L. philippinensis following the discovery of a female caught at Karachi fish harbor, Pakistan by Leene and Buitendijk (1952).
  • Benthic assemblages for ecological evaluation of Bardawil Lagoon, Mediterranean Sea, Egypt

    El komi, Mohamed Mohamed (2019)
    Bardawil Lagoon is the only highly saline oligotrophic lagoon in Egypt, has an area of ca. 650 km2 with water depths ranged 0.3m to 3m and economically important in terms of fish production. It is the optimum zone getting migratory birds in winter. It is separated from the Mediterranean Sea by a narrow sandy shelf (90 km length, and 22 km width). Ecological evaluation of benthic communities in Bardawil Lagoon to follow-up study of the distribution of benthic study at 12 selected sampling sites representing different environmental habitats for long periods through the project of Environmental Study Wetlands OF North Egyptians Lakes where samples were collected seasonally (2010-2015) and semi-annually (2015 - 2019). The results and data analysis indicated that the distribution, composition and dominance of macro benthic organisms in Lake Bardawil were composed mainly of Ostracoda, Polychaeta, Sea grasses, Bivalvia, Insecta larvae communities and dominated the constituent of bottom fauna. The variations in the benthic biomass were the heaviest at sites elRaodh and meddle elRaodh representing 1354 and 1105 g/m2 which corresponding respectively to 18.2 % and 14.9% of the annual average of benthic biomass (619 g/m2). Regional variations abundance of the benthic structure was highest at sites elTelol and elRaodh representing 3486 ind/m2 and 3635 ind/m2 which corresponding respectively to 14.8% and 15.3% of the annual average of benthic density (1978 ind/m2). Sites of sampling study were evenly spread (J’ > 0.8) at most sites except at elTelol and elRaodh also, high diversity (H’ > 3.00) was at the most sites and show lower value at sites elTelol, elGals, Boughaz I, elNaser, and Raba`a while, Swartz Dominance indexes of number of 5 species over 75% showed low values at sites elGals, Boughaz I, elNaser, and Raba`a. The abiotic environmental effects in the Bardawil Lagoon are general to those generally observed in other areas influenced by organic wastes, namely, changed in the physic-chemical properties of the sediments and low oxygen concentrations in the bottom water due to decomposition of organic materials.

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