Irish Waters Research Articles

The role of Azadinium spinosum (Dinophyceae) in the production of azaspiracid shellfish poisoning in mussels

Azaspiracids (AZAs) are a group of lipophilic polyether compounds first detected in Ireland which have been implicated in shellfish poisoning incidents around Europe. These toxins regularly effect shellfish mariculture operations including protracted closures of shellfish harvesting areas for human consumption. The armoured dinoflagellate Azadinium spinosum Elbrächter et Tillmann gen. et sp. nov. (Dinophyceae) has been described as the de novo azaspiracid toxin producer; nonetheless the link between this organism and AZA toxin accumulation in shellfish has not yet been established. In August 2009, shellfish samples of blue mussel ( Mytilus edulis) from the Southwest of Ireland were analysed using liquid chromatography–tandem-mass spectrometry (LC–MS/MS) and were found to be above the regulatory limit (0.16 μg g −1 AZA-equiv.) for AZAs. Water samples from this area were collected and one algal isolate was identified as A. spinosum and was shown to produce azaspiracid toxins. This is the first strain of A. spinosum isolated from Irish waters. The Irish A. spinosum is identical with the other two available A. spinosum strains from Scotland (3D9) and from Denmark (UTHE2) in its sequence of the D1–D2 regions of the LSU rDNA. A 24 h feeding trial of blue mussels ( M. edulis) using an algal suspension of the Irish A. spinosum culture at different cell densities demonstrated that A. spinosum is filtered, consumed and digested directly by mussels. Also, LC–MS/MS analysis had shown that AZAs were accumulating in the shellfish hepatopancreas. The toxins AZA1 and -2 were detected in the shellfish together with the AZA analogues AZA3, AZA6, AZA17 and -19 suggesting that AZA1 and -2 are metabolised in the shellfish within the first 24 h after ingestion of the algae. The levels of AZA17 detected in the shellfish hepatopancreas (HP) were equivalent to the levels of AZA1 but in the remainder tissues the levels of AZA17 were four to five times higher than that of AZA1, only small quantities of AZA3 and -19 were present with negligible amounts of AZA6 detected after the 24 h period. This could have implications in the future monitoring of these toxins given that at present according to EU legislation only AZA1–AZA3 is regulated for. This is the first report of blue mussels’ ( M. edulis) feeding on the azaspiracid producing algae A. spinosum from Irish waters.

Life history and other biological traits of the trout barbCapoeta truttain the River Meymeh (western Iran)

The trout barb Capoeta trutta is native to the Middle East only and little is known of its life-history in Iranian waters. Life history characteristics were examined in 366 specimens collected from the River Meymeh (western Iran) monthly during the reproductive seasons (March-May) of 2008 and 2009. Observed maximum age was 6 years in both sexes, sex ratio (male : female) was 1 : 1.35, and length-weight relationships were TL = 0.0266TW2.7134(males), TL = 0.0258TW2.7251 (females), and TL = 0.026TW2.7217 (entire population). Mean egg diameter (ED) was 1.61 (± 0.03 SE), ranging from 1.6 to 1.9 mm. Mean absolute (AF) and relative fecundity (RF) were 7594 (± 283.04 SE) eggs/female, and 70 (± 241.86 SE) eggs·g-1 body weight, respectively. AF and ED were found to increase significantly with increasing fish size, whereas RF decreased significantly with both fish TL and weight. Simplified von Bertalanffy growth estimates were also calculated.

Characterization of Sarcocystis fusiformis based on sequencing and PCR-RFLP in water buffalo (Bubalus bubalis) in Iran

Four Sarcocystis species, i.e., Sarcocystis fusiformis and Sarcocystis buffalonis with cats as definitive hosts, Sarcocystis levinei with dogs as definitive host, and Sarcocystis dubeyi with unknown definitive host, have previously been described from water buffalo (Bubalus bubalis). The aim of the present study was genetic characterization of the causative agent(s) of water buffalo sarcocystosis in Khuzestan Province, western Iran. RFLP-PCR and partial sequence analysis of 18S rDNA gene were used for the genetic characterization of the specimens directly obtained from water buffalo. In RFLP-PCR, four restriction enzymes (Dra1, Ssp1, Fok1 and Bsl1) were used for species discrimination of Sarcocystis spp. in this host. Comparison of the molecular sequencing results and RFLP-PCR pattern of the samples obtained in the present study with those previously reported for different Sarcocystis spp. revealed that all positive Sarcocystis samples represented S. fusiformis. To our knowledge, this is the first demonstration of the existence of S. fusiformis in the Iranian water buffalo population by a genetic approach. In addition, comparison between the alignments between the Iranian 18S rDNA sequences (HQ703791), made in this study, and those previously reported for S. fusiformis in different geographical location (accession nos. AF176927, AF176926, and U03071) showed the occurrence of local genetic polymorphisms and heterogeneity in this ribosomal locus. Despite the occurrence of some genetic variations in the hypervariable regions of the 18S rDNA in S. fusiformis, Dra I restriction site was conserved among all sequences available. According to the present study, it seems that cats have a more significant epidemiological role than dogs in transmission of sarcocystosis agent to water buffalo in Iran.

Effects of temperature and salinity on the survival and development of larval and juvenile Palaemon serratus (Decapoda: Palaemonidae) from Irish waters

The combined effects of temperature and salinity on the survival and development of larval and juvenile Palaemon serratus from the west coast of Ireland were investigated. Survival over time was measured at thirty combinations of temperature and salinity ranging from 10–19°C and 9–34‰ in a fully factorial design. Salinity had a stronger influence than temperature on survival at all larval stages except stage V. For juveniles the main effect changed from temperature between 100 and 200 degree days to salinity between 200 and 600 degree days and temperature between 600 and 800 degree days. Estimates of time taken to 50% mortality showed that juveniles tolerated lower salinities for longer periods and exhibited optimal salinity values which were 3‰ lower than larvae, at temperatures between 10 and 15°C. Larval stage durations were found to be influenced by temperature but not salinity. Comparison with published data suggests that populations of P. serratus have adapted to local conditions of temperature and salinity. The results presented here have practical implications for fisheries assessment and management, as the incorporation of environmental effects into stock–recruitment models can improve their predictive capacity.

Serum Concentrations of Lipids and Lipoproteins and Their Correlations together and with Thyroid Hormones in Iranian Water Buffalo (Bulbalus bulbalis)

Serum Concentrations of Lipids and Lipoproteins and Their Correlations together and with Thyroid Hormones in Iranian Water Buffalo (Bulbalus bulbalis)

Fine‐scale population genetic structuring of bottlenose dolphins in Irish coastal waters

AbstractThe identification of localized discrete populations is particularly important to the management and conservation of animal species, especially in the marine environment, where potential for dispersal is high but barriers to gene flow are often not clear. We investigated population genetic structuring of bottlenose dolphinsTursiops truncatusfound along the west coast of Ireland, with particular attention to the Shannon Estuary, which is the only candidate Special Area of Conservation designated for this species in Irish waters. A genetic structure analysis using 62 biopsy samples from free ranging dolphins and 23 necropsies from stranded dolphins revealed fine‐scale population structure among three distinct populations. The Shannon Estuary population appears to be genetically isolated from adjacent coastal areas, with the exception of four animals sampled from a small group of six dolphins that are now resident in Cork Harbour (south coast) indicating ongoing gene flow or recent dispersal between these two areas. A second genetically distinct aggregation was identified in the Connemara–Mayo region, where recent photo‐identification studies have suggested that dolphins found in this area show a degree of site fidelity. We found moderate nuclear (15 microsatellites) and low mitochondrial (544 bp of the control region) gene diversity in dolphins using the Shannon Estuary and the Connemara–Mayo region, while dolphins that stranded along the coast showed markedly higher levels of gene diversity at both classes of markers. Specifically, these stranded dolphins formed a third genetically distinct cluster, which may be part of a larger pelagic population, as also suggested by the high levels of gene diversity. These results provide new insights into population structure of bottlenose dolphins in Irish waters and will aid future management and conservation of the species in the eastern North Atlantic.

The conservation of seals in Irish waters: How research informs policy

Abstract Ireland's waters represent a valuable resource encompassing productive fishing grounds and important oil and gas reserves. As a species rich marine environment, Ireland's waters are also an important habitat for many species of marine mammal. Specifically, grey seals (Halichoerus grypus) and harbour seals (Phoca vitulina) are widespread in Irish coastal waters and at least 24 species of cetacean have been reported at sea. The coastal zone represents critical habitat for many of these species, in particular seals that use both terrestrial and aquatic coastal habitat and are vulnerable to habitat degradation. Increasing exploitation of marine resources has increased their exposure to a range of anthropogenic effects including pollution and habitat loss. As top predators seals interact with commercial fisheries both directly and indirectly for resources and conflicts arise. The relatively recent move towards ‘greener’ resource exploitation such as marine renewable energy does not come without negative consequences for marine mammals including seals, which are afforded protection under national and international conservation legislation, highlighting the difficulties faced by resource managers. The sustainable exploitation of resources whilst conserving biodiversity is a challenging task and effective management implementation depends on appropriate policy informed by reliable scientific data. This paper outlines the conservation needs of seals in Irish waters, reviews our current knowledge of these species in Irish water, provides a critical analysis of the existing legislative framework and describes how research outputs can inform present and future policy decisions.

THE INFLUENCE OF WATER COLUMN STRATIFICATION ON DISSOLVED OXYGEN LEVELS IN COASTAL AND SHELF WATERS AROUND IRELAND

In temperate coastal and shallow shelf waters oxygen depletion near the seabed can occur naturally as a result of seasonal water column stratifi cation. The presence of stratifi cation limits the downward mixing of well-oxygenated surface water with the result that oxygen near the bottom can become depleted as a result of biological consumption. In this paper we show that in coastal and shelf waters around Ireland a strong positive correlation (r = 0.81) exists between bottom layer oxygen under-saturation and the presence or absence of stratifi cation. A predictive empirical model based on this correlation together with an analysis of the deviation in bottom oxygen levels from a reference value of 100% saturation was used to map the bottom distribution of oxygen in these waters. The model was also used to estimate the daily rate of oxygen consumption in the bottom layer during the summer stratifi cation period (approximately 120 days) on the north-western Irish shelf. This was found to be 0.25 percentage saturation points (or 0.022mg l 1 O 2 ) per day. These fi ndings provided the basis for a discussion on the development of oxygen- and nitrogen-based environmental quality standards and the identifi cation of potentially oxygen vulnerable areas in waters around Ireland. Finally, this work demonstrates that the likelihood of large-scale hypoxia occurring in Irish waters as a result of anthropogenic nutrient inputs is very low.

Status of freshwater crayfish (Astacus leptodactylus) in Iran

Iranian native crayfish includes one crayfish species, Astacus leptodactylus, with two subspecies, A. l. leptodactylus (lives in freshwater) and A. l. eichwaldi (lives in the Caspian Sea with 12 ppt salinity). Only A. leptodactylus is commonly distributed in Iranian water resources. Nearly 80 years ago local fishermen started to catch Anzali Lagoon crayfish and sold them to foreigners and embassy employees. The consumption of crayfish in Iran is very low, approximately 1 t annually. The first commercially significant crayfish harvest in Iran was 11.3 t from Anzali Lagoon in 1985. It was carried out by a Turkish company. In 1985, the introduction of A. leptodactylus was started into suitable Iranian freshwaters. For example, crayfish from Anzali Lagoon were introduced into Arass water reservoir in 1985. Today, Arass water reservoir is the main resource of crayfish in Iran. There was no further crayfish harvest in Iran until 1993. In that year, a private Iranian company began harvesting the Iranian crayfish and exporting them to European countries. In 1993, 3.2 t of crayfish were exported from Iran. Although there have been fluctuations between years, the export of crayfish in Iran increased remarkably after 1996. The successful results of crayfish introductions gave rise to this increase. In 2003, the export of A. leptodactylus from Iran reached the maximum level (216 t). The commercial value of exported crayfish between 2000 and 2009 varied from 1.5–2.5 million US$ annually and its amount was 106–211.5 t. However, there was a reduction in the export of A. leptodactylus from Iran after 2003, to just above 100 t. In conclusion, in order to increase crayfish production in Iran, introduction of A. leptodactylus into suitable water resources, and management, conservation and monitoring of present crayfish populations should be carried out.

Annotated сhecklist of the freshwater fishes of Iran

The confirmed freshwater fishes of Iran comprise 202 species in 104 genera, 28 families, 17 orders and 3 classes found in 19 different basins. There are also 23 species whose presence in Iranian waters needs confirmation by specimens. The most diverse order is the Cypriniformes with 120 confirmed species (59.4%) followed by Perciformes with 28 species (13.9%), Cyprinodontiformes (10 species, 5.0%), Clupeiformes (9 species, 4.5%), Salmoniformes (7 species, 3.5%), Mugiliformes and Siluriformes each with 6 species (3.0%), Acipenseriformes (5 species, 2.5%), Gasterosteiformes (3 species, 1.5%), and 8 other orders each with one species (0.5%). New species are still being discovered, 7 described in 2009, while others are being resurrected from synonymy, newly recorded from Iran, or exotic species newly established. Some taxonomic problems remain and are commented on briefly. Thirty-nine endemic species (19.3%) in 6 families and 23 exotic species (11.4%) in 8 families are listed here. The mosquitofish, Gambusia holbrooki Girard, 1859 is the most widespread exotic species.

The seaweeds of Iran

The aim of this study was to identify seaweeds in the southern coasts of Iranian waters and providing an atlas. The collecting and identification of seaweeds in the southern coasts of Iranian waters were carried out from October 2001 to September 2003. Data on vegetation were gathered in sub tidal and intertidal zones by seasonal and monthly sampling, respectively. Samples were transferred to the laboratory and fixed in 4% formalin. The marine algae were recognized according to some references. In addition, the herbarium sheet and algal photos were obtained. For final approval, the prepared samples were sent to scientific centers of America, China and Pakistan. About 180 species have been collected in this research up to this time, 165 species have been identified and confirmed and the others are going to be identified. Among 165 identified species were 83 red algae species, 41 green algae species, 40 brown algae species and one blue-green algea species. The most important identified seaweed families are Ulvaceae and Caulerpaceae belong to green algae, Sargassaceae belong to brown algae and Gracilariaceae, Gelidiaceae and Hypneaceae belong to red algae that have a lot to applications in feeding, industry and medical sciences fields.

Antimycobacterial, antiprotozoal and cytotoxic potential of twenty-one brown algae (Phaeophyceae) from British and Irish waters.

In the continuation of our research on seaweeds, crude extracts of 21 brown algae collected from the south coast of England and the west coast of Ireland were screened for in vitro trypanocidal, leishmanicidal and antimycobacterial activities. Mammalian stages of a small set of parasitic protozoa; i.e. Trypanosoma brucei rhodesiense, T. cruzi and Leishmania donovani, and the tubercle bacillus Mycobacterium tuberculosis were used as test organisms. The extracts were also evaluated for selectivity by testing on a mammalian cell line (L6 cells). Only four extracts were moderately active against T. cruzi, whereas all algal extracts showed significant activity against T. brucei rhodesiense, with Halidrys siliquosa and Bifurcaria bifurcata (Sargassaceae) being the most potent (IC50 values 1.2 and 1.9 μg/mL). All algal extracts also displayed leishmanicidal activity, with H. siliquosa and B. bifurcata again being the most active (IC50s 6.4 and 8.6 μg/mL). When tested against M. tuberculosis, only the B. bifurcata extract was found to have some antitubercular potential (MIC value 64.0 μg/mL). Only three seaweed extracts, i.e. H. siliquosa, B. bifurcata and Cystoseira tamariscifolia showed some cytotoxicity. To our knowledge, this is the first study on the antiprotozoal and antimycobacterial activity of brown algae from British and Irish waters.

Economic value of conserving deep-sea corals in Irish waters: A choice experiment study on marine protected areas

Deep-water corals are slow growing, fragile and vulnerable to the impacts of deep-water fisheries and the development activities of the offshore industries. In Ireland there is now evidence of major damage to deep-water corals linked to a recent expansion of the Irish deep-water fishery. This fishery uses trawls fitted with robust rock hopping gear and employs a high risk fishing technique, which is potentially very destructive to coral habitats. Consequently resource managers have been exploring the potential of marine protected areas (MPA) as a tool for the conservation of these coral ecosystems in the North East Atlantic. MPAs aim to minimise the socio-economic costs associated with closures or other management restrictions while still achieving the desired conservation objectives. However, the decision to use MPAs (and thereby restrict fishing) is often taken in the light of uncertainty over the value of the reserved habitats to the fishing industry. This paper reports on a choice experiment study carried out in Ireland in early 2007 aimed at partly addressing this uncertainty. The study primarily focused on determining the economic value held by the Irish public for the conservation of deep-sea corals using several variants of the concept of MPAs. They have endorsed MPA strategies that banned trawling in an MPA that included all areas where corals are thought to exist with no personal tax imposed, banned trawling in an MPA covering all known corals with a personal tax imposed of €1 p.a. and banned all fishing in an MPA covering all areas where corals are thought to exist with a personal tax imposed of €1 p.a. In terms of the probabilities attached to the individual attributes, the most preferred policy options were to ban trawling, protect all areas where corals are thought to exist, and pay a ring-fenced personal tax of €1 p.a.

Trypanorhynch cestodes of teleost fish from the Persian Gulf, Iran

A total of 299 fish belonging to ten teleost species were studied in Iranian waters at the north-eastern coast of the Persian Gulf for larval trypanorhynch cestode infection. The following trypanorhynch species were identified: Callitetrarhynchus gracilis Pintner, 1931, Pseudogilquinia thomasi (Palm, 2000), Pterobothrium lesteri Campbell and Beveridge, 1996 and Pseudolacistorhynchus shipleyi (Southwell, 1929). The most abundant parasite was C. gracilis which was isolated from seven teleost species. The highest prevalence (62.9%) and dominance (0.98) were demonstrated for P. thomasi with a maximum intensity of 22 in Indian halibut Psettodes erumei. Collections of P. lesteri and P. shipleyi from the Persian Gulf represent new locality records, thus extending the known range of distribution for both species. Four new host records are established. The recorded combination of trypanorhynch species and the established host range correspond to other regions, such as off the Brazilian coast. In terms of species distribution, the north-western part of the Indian Ocean, together with the Gulf of Bengal and the Indonesian archipelago, share the same species, resulting from connected water bodies. All trypanorhynch species were isolated from the body cavity, except for P. thomasi which was recorded from the musculature of P. erumei. Relatively high intensities of infection in P. erumei may be of public health concern in the region, necessitating the consumption of well-cooked fish products.

Linguatula serrata prevalence and morphometrical features: an abattoir survey on water buffaloes in Iran

The prevalence and morphometrical characteristics of Linguatula serrata (L. serrata) nymphs in mesenteric lymph nodes (MLNs), livers and lungs of 366 Iranian water buffaloes were investigated. The infestation rate increased with age (P 0.1). In this study, 7.65% of animals had L. serrata nymphs with infection rates of 5.73% for MLNs, 1.63% for livers and 0.27% for lungs. Greyish-white coloured nymphs measured 3.5 to 4.5 mm in length, 82 to 84 mm in body segments, 44 to 46 mm in transversely striated spines and 4 mm in oral hooks. The results indicated a high rate of infestation of lymph nodes in buffaloes in Iran. Due to consumption of raw or under-cooked liver and visceral organs of buffaloes by local people, the importance of a thorough inspection at slaughter-time seems imperative.

The Movement and Migration of Shrimp, Penaeus semisulcatus in Bushehr Coastal Waters, Persian Gulf

The pattern of movement of green tiger prawn, Penaeus semisulcatus, was carried out in Bushehr waters, Persian Gulf, in 2003 and 2004. During this experiment 2571 shrimps, P. semisulcatus were tagged with green polyethylene steamer tags and released at sea from January 2003 to July 2004. During the open season of shrimps (August and September), 68 shrimps were recaptured but four of the recaptures were excluded due to inconstancies of information. The direction of movement of recaptures was mostly to the north west of the release area and to deeper waters. The majority of recaptures exhibited speed of less than 2 km/day and maximum speed was recorded at 3-4 km/day. The longest distance of 127 km was performed by a female during 95 days liberty. In the Persian Gulf the main of sea current is from the Strait of Hormuz to the Iranian waters, and probably influences the pattern of shrimp movement in the Bushehr area.

Traditional Architecture of Iranian Water Mills in Reference to Historical Documents and the Case Studies

This article is a study of the artisanship involved in the construction of Iranian Watermills, and the cultural aspects of a traditional architecture that incorporates an understanding of constructions that date back centuries. Expanding the existing knowledge of these heritage properties and explaining their current condition in order to express the need for the preservation of ancient artisanship as part of a sustainable conservation future are the other prominent concerns of this work.Herein, historical and contemporary documents and travel accounts concerning the traditional buildings of the Iranian water-mills are studied to achieve a better understanding of the buildings background in the region. In addition, depending on the information accessibility and the existence of the constructions` remains, the authors chose some historical sites to be aware of the buildings` current condition and their exact functions based on observational studies. The article discusses that Iranian traditional Water mills represent knowledge of a highly developed technology which makes such ingenious use of natural resources without the consumption of additional power. Among different Iranian Traditional constructions, water-mills are the subject of the main body of this article.

EU Water Framework Directive-River Basin Management Planning in Ireland

The European Union (EU) Water Framework Directive (WFD) (2000/60/EC) was transposed into Irish law by Statutory Instrument Nos. 722 of 2003, 413 of 2005 and 218 of 2009, which set out a new strategy and process to protect and enhance Ireland's water re- sources and water-dependent ecosystems. The Directive requires a novel, holistic, integrated, and iterative process to address Ireland's natural waters based on a series of six-year planning cycles. Key success factors in implementing the Directive include an in-depth and balanced treatment of the ecological, economic, institutional and cultural aspects of river basin management planning. Introducing this visionary discipline for the management of sustainable water resources requires a solemn commitment to a new mindset and an overarching monitoring and management regime which hitherto has never been attempted in Ireland. The WFD must be implemented in conjunction with a myriad of complimentary directives and associated legislation, addressing such key related topics as flood/ drought management, biodiversity protection, land use planning, and water/wastewater and diffuse pollution engineering and regula- tion. The critical steps identified for river basin management planning under the WFD include: 1) characterization and classification of water bodies (i.e., how healthy are Irish waters?), 2) definition of significant water pressures (e.g., agriculture, forestry, septic tanks), 3) enhancement of measures for designated protected areas, 4) establishment of objectives for all surface and ground waters, and 5) inte- grating these critical steps into a comprehensive and coherent river basin management plan and associated programme of measures. A parallel WFD implementation programme critically depends on an effective environmental management system (EMS) approach with a plan-do-check-act cycle applied to each of the evolving six-year plans. The proactive involvement of stakeholders and the general public is a key element of this EMS approach.

First documented record of Rhabdomolgus ruber (Echinodermata: Holothuridea) in Irish waters

First documented record of Rhabdomolgus ruber (Echinodermata: Holothuridea) in Irish waters

An ecomorphological framework for the coexistence of two cyprinid fish and their hybrids in a novel environment

Niche variation between hybrid taxa and their parental species has been deemed imperative to the persistence of hybrid populations in nature. However, the ecological factors promoting hybrid establishment remain poorly understood. Through the application of a multidisciplinary approach integrating genetics, morphometry, life-history, and trophic ecology, we studied the hybrids of roach (Rutilus rutilus L.) and bream (Abramis brama L.), and their parental species inhabiting an Irish lake. The roach × bream hybrid exhibited a body shape intermediate of that of the parental species. Diet analyses depicted the hybrid as a generalist, feeding on all prey items consumed by either parental species. Stable isotope data confirm the trophic niche breadth of hybrids. A significant correlation between body shape and diet was detected, suggesting that the intermediate phenotype of hybrids might play a role in their feeding abilities, resulting in the utilization of a broader trophic spectrum than the parental species. Growth and age class structure analyses also yielded a scenario that is consistent with the ecological success of hybrids. Genetic analyses suggest that the majority of hybrids result from first-generation crosses between the parental species; however, a potentially significant proportion of back-crosses with bream were also detected. The recent introduction of roach and bream into Irish waters, as well as the climatic and ecological features of the colonized habitats, can explain the remarkable success of the roach × bream hybrid in Ireland. The adaptive significance of hybridization and its demographic consequences for the parental species are discussed. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99, 768–783.