Ehsan Kamrani

Population genetics of the fiddler crab Uca sindensis (Alcock, 1900) (Crustacea: Brachyura: Ocypodidae) from the Arabian Sea

BackgroundThe fiddler crab Uca sindensis (Alcock, 1900) (Crustacea: Brachyura: Ocypodidae) is distributed in the northern coasts of the Arabian Sea (Pakistan, Iran, Iraq, and Kuwait). Its typical habitat is on high intertidal areas with higher salinity, which might restrict its distribution, especially within the Persian Gulf. The purpose of the present phylogeographic study is to understand whether the Strait of Hormuz acts as a barrier to the gene flow of this species.ResultsThe genetic analyses of the mitochondrial 16S rRNA, cytochrome oxidase subunit I (COI), and control region (CR) of specimens from various localities showed that there was no genetic differentiation between the populations inside and outside of the Persian Gulf.ConclusionsWe conclude that the narrow Strait of Hormuz does not form a barrier for the larval dispersal in this species. Its restricted distribution in the northern Arabian Sea may instead be associated with its preference for higher salinity sediments present in the coasts of this region.

Study on the behaviour of two fiddler crabs, Uca sindensis and Uca annulipes (Decapoda: Ocypodidae), in Bandar Abbas, Iran

This study was carried out on the behaviour of two species of sympatric fiddler crabs on Abi estuary, Bandar Abbas, Iran. Species differences in activity level, grooming, burrowing, muddy structure construction and feeding were all related to their habitat and food source. The more common Uca annulipes lives in low muddy areas along the edges of small streams while Uca sindensis lives in small patches on the higher areas with sandier sediment. At low tide, both species spent most of their time feeding, while at high tide they retreated into their burrows. Both species frequently walked while feeding and interacted aggressively. There were similarities in the feeding behaviour of these species: they fed at the same times of the tidal cycles, they were more likely to engage in courtship and mating behaviour during February-September and were least aggressive at this time. In both species, crabs excavated mud balls from their burrows and placed them away from their burrow entrances. There were, however, also differences between the species. Uca annulipes constructed mud hoods at the entrance to their burrows while U. sindensis did not; and the species differed in feeding rate.

Condition factor and carapace width versus wet weight relationship in the blue swimming crab Portunus segnis

The size-weight relationship of a species allows for estimating the expected weight based on size. The present contribution aims at evaluating the body weight vs. carapace width relationship and the condition factor of the blue swimming crab Portunus segnis. These characteristics were analyzed for each sex using specimens collected monthly from April 2012 through to March 2013, at the Persian Gulf (Hormozgan Province, Iran). The size of each specimen was measured (carapace width) and weighed (total body wet weight). A total of 302 individuals of P. segnis were analyzed. The body weight-carapace width relationship indicated positive allometric growth in males and isometric growth in females. Body weight was higher in males than females of equivalent carapace width, and the means for condition factors were always higher in females than in males, due to the heavier gonads in the former, an expected pattern for many crabs. In both sexes, the lowest condition factor was detected in winter with an ascending trend in the next seasons. The oscillation in condition factor throughout the sampling year was more prominent in females and related to the reproductive cycle. The information reinforces data to define fishing closed seasons for this portunid that is used in many places in the world.

A new species of freshwater crab of the genus Sodhiana Yeo & Ng, 2012 (Decapoda: Brachyura: Gecarcinucidae) from southern Iran.

A new species of freshwater crab, Sodhiana iranica n. sp. (Decapoda: Brachyura: Gecarcinucidae), is described from Bastak, Iran. This is fourth species of Sodhiana Yeo & Ng, 2012, described, and is the second one known from Iran. It can be distinguished from congeners by the form of its carapace and the structure of the male first gonopod.

Mean trophic level of coastal fisheries landings in the Persian Gulf (Hormuzgan Province), 2002–2011

Fishing activities can alter the structure of marine food webs by the selective removal of some species. The changes in the marine food webs of the Hormuzgan waters of the Persian Gulf, Iran were assessed, based on estimates of the mean trophic index (MTI) and Fishing in Balance index (FiB), and on landing profile of the exploited marine community (49 species) during the period, 2002–2011. The total landings (Yt) (R=0.88, P<0.001) increased gradually while the Yt of carnivores has slightly declined, and the Yt of herbivores, detritivores and omnivores has increased. Consequently, the MTI significantly decreased (R =-0.69, P<0.05) at a rate of 0.11 during this decade. The MTI showed a decreasing trend, which indicates exploitation of marine resources. The FiB index also showed a downward trend and negative values from 2002 to 2009, which may be associated with unbalanced structure in the fisheries, but an upward trend from 2009 to 2011. The time variation of the landing profile showed two periods with significant diff erences in their species composition (R=0.88; P =0.005), and based on analysis of similarity, species have been identified as discriminator species, namely Thunnus albacores and Benthosema pterotum. Results indicate that changes in MTI reflected changes in the Hormuzgan landing structure. The examination of the MTI, FBI, and landing profile (LP) temporal pattern suggests that the status of fishery resources in Hormuzgan inshore waters is overexploited, and provides evidence of the probability that a fishing down process is occurring in this area, and that this trend may continue in the long-term. Therefore, environmental fisheries management and conservation programs should be prioritized for these valuable resources.

Responses of the killifish (Aphanius dispar) to long-term exposure to elevated temperatures: growth, survival and microstructure of gill and heart tissues

Some fish species, such as killifish, that normally inhabit temperate water environments are also found in extreme thermal environments such as thermal springs. The extent of the adaptations involved is not known. In the present laboratory study, we exposed killifish (Aphanius dispar) acclimated to a normal thermal environment to elevated temperatures (37–40 °C) in which related killifish species live permanently. Our objective was to determine whether there is evidence that killifish have heat-shock characteristics that make permanent adaptation likely. The fish was exposed to this temperature for a period of 44 days and then compared with control fish kept at their normal temperature (24 °C) with respect to growth, survival and histopathology of gill and heart tissues. At the end of the experimental time, the percentage of body weight gain and specific growth rate were significantly lower in fish kept in thermal stress compared with the control group. Feed conversion ratio (FCR) was also significantly affected by water temperature, so that during thermal stress the values of FCR were negative. Fish condition (Condition factor: CF) did not differ significantly between both groups at the end of the experiment. On days 11 and 33, however, CF was significantly lower in the thermal stress group. The gill showed blood congestion in primary lamellae and shortened secondary lamellae in fish kept at 37–40 °C. No specific alterations were found in the cardiac tissue of fish kept in thermal stress conditions. Under thermal stress, 40% of fish survived until the end of the experiment. A preliminary conclusion drawn from this work is that A. dispar, which lives at normal temperatures, shows evidence of adaptability to elevated temperatures that could be a factor in the ability of killifish to adapt permanently over time to thermal environment.

Fishery-induced Inter-annual Changes in the Mean Trophic Level, the Northern Sea of Oman off the Iranian Coast, 2002–2011

Ecosystem-based management is one of the most important approaches that may lead to reducing the impacts of fishing on ecosystems. In this context, we have assessed the impact of Iranian coastal fishing (using landing data of 49 exploited species) on the ecosystem of the North Sea of Oman (Sistan and Baluchestan Province), during the last decade (2002–2011), with emphasis on testing the occurrence of the “fishing downˮ phenomenon. The Mean Trophic Level (MTL) and Fishing-in-Balance (FiB) index are two indicators that we used for analysis. The data indicated that the increased total landings in this region might be related to the exploitation of marine fishery resources especially with regard to large pelagic fish. Over the past decade, moderate decreasing trends in MTL and an increasing trend in the FiB-index were observed. In this regard, an upward trend in the spatial expansion factor and also a downward trend in the piscivory index and in Primary Production Required (PPR) in the time period could all indicate a spatial expansion toward deep waters, the catching of the large pelagic piscivorous species, such as tuna, and a sign of fishing pressures on the ecosystem. The results suggest a range of fishery exploitation patterns throughout the food web but it seems that these patterns are not a consequence of ʻfishing downʼ. We suggest that the monitoring research be continued in this region and these indicators should be used to make fisheries management decisions and to prevent the continuance of this trend in future.

Short Communication: Comparison of three different traps for catching oriental river prawn (Macrobrachium nipponense)

One of the comparison methods for evaluating fishing gears efficiencies is based on Catch per Unit Effort (CPUE). In this study, we used three different types of traps for catching oriental river prawn (Macrobrachium nipponense). Capture efficiencies and catch rates of cylindrical pot, opera house trap, and Hokkaido pot were compared with each other during the investigation in Anzali Lagoon. The results indicated that there is a significant difference (P˂0/05) among the amounts of CPUE of cylindrical pot (0.24±0.12 gr), opera house trap (4.17±0.84 gr) and Hokkaido pot (1.58±0.41 gr). There was a significant difference between the results of length frequencies of captured prawns that was trapped by cylindrical pot and opera house trap (P<0.05). Hokkaido, cylindrical and opera house traps were not significantly different from each other for length frequencies. The results indicated that opera house trap was an appropriate fishing gear for catching oriental river prawn because it had higher catch rates and caught prawns with higher length frequencies.

Illegal, Unreported, and Unregulated Fisheries in the Hormuz Strait of Iran: How the Small-Scale Fisheries Guidelines Can Help

According to a United Nations report, illegal, unreported, and unregulated (IUU) fishing is the main hindrance for sustainable fisheries in the open seas and inland waters. In this chapter, we explore how the Voluntary Guidelines for Securing Sustainable Small-Scale Fisheries (SSF Guidelines) can help address this problem and improve the sustainability of small-scale fisheries and local community livelihoods in Hormozgan Province of Iran and the Persian Gulf. At present, there is limited management planning for small-scale fisheries in Iranian waters, and information about IUU fishing is scarce. Nonetheless, IUU fishing is on the political agenda. In Daliri et al. (Ocean & Coastal Management 120:127–134, 2016), we explored what factors cause IUU fishing in the region, and highlighted culture, management, economic conditions, personal skills, and area features as important determinants of IUU fishing. We also concluded that co-management can help address this problem and promote more sustainable fisheries in this region, if implemented well. In this chapter, we argue that efforts to reduce IUU fishing must include multiple measures identified throughout the SSF Guidelines, measures that go beyond the paragraph that talks specifically about monitoring, control, and surveillance (MCS).

Study of Feeding Regime of Sea Cucumber Stichopus herrmanni Using Nutritional Indices on Coral Reefs of Southeast of the Qeshm Island, Persian Gulf

This study aimed to investigate the sea cucumber Stichopus herrmanni diet in coral reef located southeast of the Qeshm Island and other nutritional indices. Sampling was done seasonally (10-15 samples in each season) in southeast of Qeshm Island (area around 515000 m) and intestinal contents were examined as a standard method. In this study, Diatoms, blue green algae, Micro benthic animals (foraminifers, nematodes and gastropod) as main prey were detected in the intestinal contents in this species. During different seasons, changes observed in the index of fullness and vacuity index of intestine and RLG Index was over one. In general, it seems that the diet changes happening in this beast is affected by different stages of life including sexual maturation and spawning.