Species diversity and distribution pattern of marine mammals of the Persian Gulf and Gulf of Oman - Iranian Waters

A total of 98 marine mammal records from Iranian coastal waters of the Persian Gulf and Gulf of Oman were compiled of which 66 are previously unpublished new records. Seventy-nine were from the Persian Gulf and 16 from the Gulf of Oman coast. The largest numbers of records were from Qeshm Island and Bushehr Provinces. Records of finless porpoise (Neophocaena phocaenoides), Indo-Pacific humpback dolphin (Sousa chinensis) and Indo-Pacific bottlenose dolphin (Tursiops aduncus) were by far the most numerous probably reflecting their inshore distribution and local abundance. Other species recorded are common dolphin (Delphinus capensis tropicalis), rough-toothed dolphin (Steno bredanensis), Risso’s dolphin (Grampus griseus), false killer whale (Pseudorca crassidens), and dugong (Dugong dugon). Evidence of 22 Mysticetes were obtained eight of which were tentatively identified as Bryde’s whales (Balaenoptera edeni), three as fin whales (Balaenoptera physalus) and three as humpback whales (Megaptera novaeangliae). The largest threat to marine mammals in Iran is likely to be incidental capture in fishing gear. Six by-caught finless porpoises were recorded, and this species may be particularly vulnerable to incidental mortality in gillnets. Recommended marine mammal research, conservation and management small projects in Iran are described

The effect of monsoon on fish larva assemblage changes in Gowatr Bay, North Oman Sea

The study and research of abundance and diversity variation of fish larva (Ichthyoplankton stages) was done in Gowatr Bay during autumn 2006 - summer 2007. Five stations were selected for sampling, and Bongo-Net with 300µ mesh size was towing from bottom to surface. During of survey, totally 531 larvae belong to 11 families were collected and identified. The mean abundance estimated 12.17 larvae per 10 m^2, in which three fish larva family including: Gobiidae, Clupeidae and Engraulidae were dominant (86% of relative abundance). The result showed that there was significant differences between pre and post-monsoon fish larvae abundances (p.05). In pre-monsoon 4 families were identified of which Clupeidae introduced as indicator group, whereas in post-monsoon 10 families were identified and Gobiidae was indicator family, accompany with increase of diversity. PCA result was shown, temperature as the main factor affected on fish larvae assemblage was found with a significant decrease of 11.9 °C after monsoon phenomenon

Study on meiobenthos abundance and their relationship with the condition of sediment in the northern creek of the Bushehr province

The frequency and distribution of meiobenthoses in northern Creeks of the Bushehr Province during autumn2000- Summer200I were studied for determining the condition of sea sediments using seasonal sampling. Samplings were carried out in 10 stations from Doube Creek to Bandar Genaveh Creek as well as a control station in the Persian Gulf. Totally, 4 taxa of meiofauna were identified that Ostracoda and Gastropoda with 29% and 18% had the maximum and minimum percent of abundance, respectively. The maximum percent of abundance in station No.10(control station at sea) with 20735 n/m2 and the minimum abundance in station No.2 (Creek of Farake)with 5320 n/m2 were observed. The maximum abundance of meiobenthos in spring with 167603 n/m2 and the minimum abundance during winter with 61365 nlm2 were determined. In addition, grain size, soil texture and total organic matter (T.O.M) of sediment in 10 stations were analyzed. Results showed that station No.10 with 11.79% had the maximum percent of T.O.M while the minimum T.O.M (3.87%) in station No.4 (Gasir Creek) was observed. The correlation of sampling station based on the abundance of meiobenthos was also analyzed

Ecological classification of southern intertidal zones of Qeshm Island, based on CMECS model

The “Coastal and Marine Ecological Classification Standard (CMECS)”, a new approach to ecological classification, was applied to 122 km of the southern intertidal zone of Qeshm Island located the Hormouz Strait - the Persian Gulf. Two components of this model, Surface Geology (SGC) and Biotic Cover (BCC) were used. Considering the extent and geomorphological alternations of the covered area, 12 sampling sites within 5 sub-regions were designated using by GPS. In total, 60 habitats (biotopes) with 47 codes were determined; this variety of biotopes is directly related to the diverse surface geology (substrate) of the covered area. Most of the biotopes and codes were recorded in the mid-eastern coastal zone, due to heterogeneity in substrate structure associated with numerous ecological niches in rocky shores. Crustacean species such as Eriphia smithi, Thalamita prymna, Molluscan species such as Clypeomorous bifisciatus, Cerithium caeruleum and echinoderm species such as Echinometra mathaei and Ophiactis sp. were characteristic of rocky shores, while Crustacea groups including Ocypode rotundata and Dotilla sp., and Umbonium vestiarium (Mollusca) were characteristic of sandy shores. Although the highest number of codes was recorded in Zeitun Park site (Eastern coast), it did not possess the expected specific species (such as Diadema setosum, Linckia multiflora and Ophiocoma scolopendrina), that were encountered in sites with similar surface geology. This could have been caused by tourist traffic at the Zeitun Park site

Short communication: Ecological classification of southern zones of the Caspian Sea (Mazandaran Province), based on CMECS model

A coastal area is a confluence of land and marine ecosystems and includes the independent biological, ecological, and geological area. Increasing pressure on these areas can decrease the quality of marine habitats, and can even lead to the loss of sensitive habitats. In this regard, a “biotope” has been suggested as the most informative operational unit for research and management. These biotopes, however, have been specified by the dominant species; they depend on the seabed, they are stable, and sometimes are used synonymously with the word ecology. Habitat classifications are, therefore, most accurate and ecologically relevant at the biotope level because of the direct relationship between the biota and their environment. The Coastal Marine Ecological Classification Standard (CMECS) was developed with the input of over 40 coastal and 20 marine habitat experts and presents a universally accepted standard classification for coastal and marine habitats. ... We classified the eastern coast of Mazandaran Province (Babolsar to Amirabad Port) and then encoded this zone based on the CMECS model

Identification of a hermit crab, Clibanarius signatus, in Hormuz Island: abundance, sex ratio and shell selection behaviors

In order to establish a complete list of the hermit crab species in the southern coast of Iran and also determine some of their biological characteristics in the intertidal zones of Hormuz Island, a seasonal sampling collection was conducted in 6 intertidal stations during the years 2010–2011. The 542 collected samples were found to be Clibanarius signatus, which identified in the island. Comparing the samples with the metatypical hermit crab samples in the Zoological Museum, University of Tehran, verified the species. The one ways ANOVA with LSD test showed a significant difference (p < 0.05) in the abundance of the species in some stations, but seasonal changes did not significantly affect the abundance. Male-female sex ratio was 1/52 male: 1 female. Seasonal study of sexes (male, non-ovigerous female, ovigerous female) confirmed that species did not have a particular spawning season, nevertheless the spawning increased in summer. The shell selection behaviors showed that the hermit crab uses the shells of 36 gastropod species (24 genera) for protecting its abdominal section

Study of distribution, abundance and biomass of macro benthic fauna in the northern creeks of Bushehr province

Macro benthic invertebrate distribution and abundance in northern creeks of Boushehr province were analyzed by seasonal sampling from autumn 2000 till summer 2001. Sampling was carried out of sediments from bottom of nine stations which located in creeks and one control station in the sea by using of Van Veen Grab sampler. In additional, eight groups of macro benthos were identified which the most abundant populations among them were Gastropoda (51%), Bivalvia and Polychaeta (17.4%) and Amphipoda (5.3%) respectively. The maximum density of macro benthos was 2378 ind/m2 in spring and the minimum was 1174 ind/m^2 in autumn and also maximum and minimum biomass was 79.06g/ m^2 in summer and 17.72g/ m^2 in winter. The average wet weight of macro fauna biomass was 49.95 (± 33.6) g/ m^2

Ecological classification of intertidal biotopes in north Qeshm Island based on coastal-marine standard (CMECS)

The “Coastal and Marine Ecological Classification Standard” is one of the new and complete approaches to understand of marine habitats. We were applied Biotic Cover and Surface Geology as the two components of the classification to the northern intertidal stretch of Qeshm Island. Considering the extent and geomorphology of the area, 9 sites were designated. Density and temporal distribution of biotic community were determined using 0.5×0.5 m quadrate, and sediment was sampled up to 15 cm below the surface to determine its type and material. Totally 32 codes were determined for 40 habitats (biotopes), and their positions were displayed on map. Our result show that the biotope diversity decreases westward. Also, the highest and lowest numbers of species were observed in sandy and muddy-sand substrates, respectively. It seems that habitats distribution is mainly determined by the substrate type, but other factors can also affect this distribution

Hydrology and hydrobiological study of the Iranian waters in the Oman Sea

In this survey, hydrology and hydrobiologycal studies in the northern part of the Oman Sea and Strait of Hormuz within the Iranian waters were conducted during 2007 and 2009.The project was implemented using Ferdous research vessel.The sampling area included the whole stretch of the Iranian waters along the northern part of the Oman Sea from the northeast of the Iranian marine border of 30 miles Bay of Chabahar to the mouth of the Hormuz Strait in Hormuzgan province. Along this stretch 10 equally distributed transects at a distance of 30 miles away from each other were designated, 4 main sampling stations at a distance of 10 miles from one another were fixed at each transect. Sampling was conducted twice a year (spring and autumn 2007 and 2009). According to achieved results; we can point out to the following outlines below: permanent thermocline exists annually in this body of water; where only the point of start, and the fracture width of thermocline layer; alter with alteration of seasons. Horizontal and vertical distribution of electrical conductivities, obey exactly from thermal degree structure.Level of salinity increase from east to west, but it decrease; from surface to deeper layers. In deeper regions, especially in the midway east of the Oman Sea; the level of salinity in the deeper waters from 150-300m, there is a considerable increase observed in salinity, due to very high salinity waters of The Persian Gulf; that are entering the Sea of Oman, via the Striate of Hormouz from the bottom; where they are having their effect following the whole length of the Sea of Oman; through their path. The level of water density from offshore to onshore, and from surface to deeper levels increase in such a way that. The level of Chlorophyll-a in surface waters, in the northeastern midway; is higher than the northwestern midway of the Sea of Oman, and it decreases from inshore to offshore waters, but its vertical distribution; has caused somehow in a way, that the highest distribution and concentration of chlorophyll-a; to be formed in deeper layers, between about 10-40m depths. Then by the increase in water depth, its concentration decreases drastically; reaching zero in magnitude. Concentration of dissolved oxygen is higher in spring in comparison to that of autumn, and the highest level is achieved in water layers located at 10-40m depth (where the level of chlorophyll-a is higher). In addition to which, that its vertical structure; shows the existence of a permanent oxycline layer at this region, in a way that; by seasonal alterations (similar to that of thermocline layer), only the point of start and that of the thickness of oxycline layer changes.pH level decreased from water surface, and its vertical alteration trend; obeyed to that of the same for temperature and chlorophyll-a vertical structure, especially for dissolved oxygen parameter, where the maximum decrease was recorded coinciding with formation of oxycline layer.Nutrient levels increased; at surface water layers from offshore to inshore, and from west to east, for the same body of water. In addition to that, concentration of nutrients in autumn (after monsoon); were more than that of, spring season (before monsoon), where; concentration of their vertical structure increase from water surface toward deeper sections. In this survey six phylum of phytoplankton including in Bacillariophyta (88) Pyrophyta (111), Cyanophyta (6), Chropmophyta (2), Euglenaphyta and silicoflagellate (1) were identified. A result showed that density decreased in most transects from inshore toward sea and maximum density was in photic layer (0-25m). Phytoplankton densities (without Cochlodinium density) in post-monsoon were recorded higher than pre-monsoon, furthermore phytoplankton density in 2009 was more than 2007(6073±1038) Species richness was indexed in the pre-monsoon and post-monsoon 2007 (0.337-0.519), (0.296-0.396) respectively and to (0.967-1.525), (1.407-1.531) for 2009. Zooplankton population in this study is characterized by eight phyla, eight classes, 15 orders, 35 families and 78 genus. In 2007, the pre-monsoon percentage of groups were frequently as following: Copepoda with stages of Nauplius and Copepeditide were 78%, Ciliphora 8%, Sarcomastigophora 4% and Hemichordata 6%. In post-monsoon order of frequency Copepoda 80%, Ciliophora 6%, Coelenterata 5%. Copepoda was the most abundant group of zooplankton.In 2009, The pre-monsoon Copepoda (82%), Cilillophora(9%), Sacromastigophora(4%) and Hemichordata (2%) in post-monsoon Copepoda(70%), Ciliophora (20%),Sarcomastigophora(4%) and Hemichordat (2%) dominante group were respectively. The static result showed significance betweendifferent transects and layers.We were recorded 31 ichthyoplankton families with different density and distribution during 2 years. Among benthic invertebrate polychaete with average 800 ind-2 and then amphipods and gastropods were the most abundance.Yearly density of macrobenthos showed polychaete with the average of 500 ind.-2 in 2007 and 1000 ind.-2 in 2009 was the most abundance . Macrobenthos density in postmonsoon was more than premonsoon.p0.05.There was a negative regression between macrobentos density and depth(p<0.05) and positive rsgresion between macrobenthos and oxygen concentration and temperature.(p<0.05).There was also a significant relationship between macrobenthos ,coppepda and polychaete density with organic carbon.p<0.05.Bimass changed from strait to Golf and coast to depth increasingly.p<0.05. The results of the measurement of heavy metals in water and Sea bed showed that the Concentration of heavy metals in surface layers in waters of the northern half of Oman Sea and Strait of Hormuz in spring (pre-monsoon) is more than autumn (after monsoon), and Degree of pollution in these areas are low compared to the global scale, Also, The results of the degree of contamination of sediments across the northern half of Oman Sea and comparison Global indicators of environmental quality assessment, it was found that the degree of contamination in the area in spring and autumn are low pollution. Comparison of the TPAH concentration of in Iranian waters of the Gulf of Oman, with other parts of the world indicate that degree of pollution of the waters in the spring 86 in the other seasons too low to medium level is low; but the degree of contamination in sediments, both in spring and in the autumn is much less; It means that the current risk on behalf of these contaminants, does not threaten the fish and benthos. The results of the risk assessment (THQ) of heavy metals in consumer, for yields Sangsar fish and fish Gish showed that the risk for both all the heavy metals, significantly lower than the one(1<) and This means that urban communities in the province does not present any danger of feeling threatened

Study on biological factors for artificial reefs in Hormozgan Province (Bandar Lengeh area)

This study was carried out for growth of organism’s survey on artificial reef from 2004-2006 after establishment in Hormozgan offshore waters (Bandar Lengeh area). Also during this study we were examined some biological factors including: phytoplankton, zooplankton, ichthyoplankton and benthos from spring 2006 to winter 2006. In this study 43 phytoplankton genus were identified, 28 Bacillariophyceae (Diatom), 11 Dinophycea, 3 Cyanophycea and 1 Euglenaphycea. Bacillariophycea were dominant, Cyanophycea were high density observed in summer and Euglenaphycea was only observed in winter. The most abundant genus of diatoms were: Rhizosolenia, Navicula, Nitzschia, Coscinodiscus. Ceratium, Prorocentrum and Protoperidinium belong to Dinophycea, Oscillatoria belong to Cyanophycea were more than other genus. Copepoda and Nauplius were the most zooplankton and other group were respectively: Oikopleura, Polychaeta and Chaetognatha. The highest density of zooplankton was seen in winter. The statical study between different stations didn't show any significant (p>0.05). 6 ichthyoplankton families were seen and identified. These families were Clupeidae, Gobbidae, Callionymidae, Sparidae, Engraulidae and Scianidae. The high density were respectively in summer and spring. The highest annual mean belong to Gobbidae family. Benthos groups were including: Crustacea, Mollusca, Polychaete, Nematoda, Nemertin, Foraminifera, Opiouridae and Echiura. Annual high density of Crustacea were observed in spring season, Polychaete and Mollusca were observed respectively in summer and winter. Organisms which growth on the artifical reef were consist of 12 group. These Organism were Barnacle belong to Crustacea with one genus (Megabalanus tintinnabulum), Sponga with 5 families and Tunicate. The highest density was in 2005. We were seen increasing in size in some organisms such as Crab, Polychaetes, Bivalvia and Fish Larvae. Statical study didn't show any significant between organisms in different parts of artificial reef (top, mid, bottom) and kind of artificial reef had no effect on growth of organisms but Barnacles had high density on mixed artificial reef