Mediterranean Coast Of Israel Research Articles

The Indian scad (<i>Decapterus russelli</i>), (Osteichtyes: Carangidae), a new Indo-Pacific fish invader of the eastern Mediterranean

The Indian scad, Decapterus russelli , is recorded for the first time from the Mediterranean. The presence of this Indo-Pacific species on the Mediterranean coast of Israel is evidently due to migration from the Red Sea via the Suez Canal. The collection of six specimens in the Mediterranean suggests that this species is well established in the Levant.

Shoreline sensitivity to oil spills, the Mediterranean coast of Israel: Assessment and analysis

This study, which was carried out during 1999–2002, deals with the identification of the environmental sensitivity of the Mediterranean coastline of Israel to marine oil spills. It includes GIS sensitivity mapping and an analysis of the environmental vulnerability of Israel's shoreline resources. The study analyses the main sources of risk for maritime accidents in the southeastern Mediterranean and develops scenarios for possible oil spills incidents, including an analysis of the priorities for protection of the various coastal ecosystems, in an event of a large spill. It describes the morphology of the coastline of Israel, as well as the main hydrographic and meteorological patterns that dominate and control the dynamics of the shorelines, and of potential major oil spills. The study also discusses the different ways in which oil spills may affect natural ecosystems and socio-economic resources along the coastline of Israel. The basic research question of the study was how different geomorphic and land-use types of the Mediterranean shoreline would be affected by large quantities of spilled oil washing ashore from the sea. The study aims at determining the relative sensitivity of different types of shoreline and ‘prioritizing’ the different types of shoreline and coastal resources to be protected following a large oil spill. The study also aims at presenting the data collected and analyzed to both the scientific and environmental communities, and to the operational national authorities responsible for oil spill preparedness and response, in a clear and useful way. One of the main conclusions of the study is that generally, the sensitivity of the Israeli Mediterranean coastline to oil spills could be considered moderate, compared with other fragile ecosystems. This is mainly because of the morphology of the sandy beaches and the high exposure of most types of beaches to energetic natural cleanup processes. Still, along the southeastern Mediterranean coastline there are ecosystems, habitats, shoreline types and coastal resources that are sensitive to oil spills.

Drowning and Beach-Safety Management (BSM) along the Mediterranean Beaches of Israel—A Long-Term Perspective

Along the 190 km of the Israeli Mediterranean coast, of which only about two-thirds is accessible to bathing activities, there are about 100 statutory surf bathing beaches guarded by professional sea lifeguards. The rest of the accessible Israeli Mediterranean coastline is divided into two additional legal categories, which are not guarded: (A) beaches where bathing is forbidden by governmental ordinance because they are too dangerous. (B) Beaches where swimming is freely permitted but not guarded. The estimated number of drowning victims in the Israeli Mediterranean surf since 1948 is about 2200. Reported drowning data show that, since 1973, the number of drownings in the surf has been about 1200 victims. There are almost no drownings reported within the perimeters of the official guarded beaches. The Israeli Mediterranean relative drowning number (RDN) in the surf per million inhabitants reveals for the last 32 years a long-term quasi-stable average of 8.1 and a SD of 2.7. The estimated average number of drownings for the present population would be about 56 victims. The Israeli RDN is higher than that of other Mediterranean countries and probably of other beaches in the world. In this article, I study the Israeli beach-safety management (BSM) schemes and identify and examine the various long-term and short-term temporal variations in drowning patterns, some demographic patterns leading to the identification of some risk groups and some other human, cultural, and managerial factors that seem to be typical for Israeli beaches and relate them to the drowning statistics. The high drowning figures in Israel seem to reflect both the meteorological and oceanographic conditions of Israel's Mediterranean coast and the BSM schemes. I suggest that Israeli RDN can, however, be reduced by proper modern scientific and managerial approach.

Population dynamics of zooxanthellae during a bacterial bleaching event

Each summer 80–90% of the colonies of Oculina patagonica undergo bleaching off the Mediterranean coast of Israel. To investigate fluctuations through a yearly bleaching cycle, monthly measurements of zooxanthella density, mitotic index and chlorophyll-a concentration were conducted. Results showed (1) a significant negative correlation between sea surface temperature (SST) and zooxanthella density; (2) both significantly lower zooxanthella mitotic index and higher chlorophyll-a per zooxanthella content during the bleaching season compared with the non-bleaching period; (3) prior to bleaching, a lag between the peak of zooxanthella density and chlorophyll-a concentration followed by a similar lag during recovery. Zooxanthella density declined significantly between March and May while chlorophyll-a concentration peaked in April, and then declined. Zooxanthella density increased significantly in November while chlorophyll-a concentration increased significantly in January. We conclude that during bacterial bleaching events, zooxanthellae are severely damaged. However, by the time of the following bleaching event the coral tissues regain their “normal” (pre-bleaching) zooxanthella population density.

First Mediterranean record of the Indo-West Pacific mantis shrimp, Clorida albolitura Ahyong & Naiyanetr, 2000 (Stomatopoda, Squillidae)

To date, only one species of Erythrean stomatopod, Erugosquilla massavensis (Kossmann), has been reported from the Mediterranean Sea. We report the first appearance of a second Erythrean stomatopod species from the Mediterranean coast of Israel, Clorida albolitura Ahyong & Naiyanetr, on 24 May 2006.

Cloning and expression of MDR transporters from marine bivalves, and their potential use in biomonitoring

Multidrug resistance transporters (MDRs) are excellent candidates for molecular-level biomonitoring - they function in exporting xenobiotic compounds and their expression is inducible. However, currently available MDR sequence information from aquatic invertebrates is partial and mostly biased towards the conserved ATPase domain. In the present study, two genes belonging to the MDR/TAP (ABCB) family were cloned and characterized from the bivalve Brachidontes pharaonis, which thrives in rocky environments along the Israeli Mediterranean coast. One of these is a complete sequence of a 'half'ABCB, probably belonging to the ABCB10 subfamily, while the second is a 'full'ABCB1 transporter. A quantitative RT-PCR protocol for biomonitoring was tested in laboratory experiments. Bivalves exposed to diesel showed significant increase in B1 expression levels, while the expression of B10 was suppressed. These results suggest that B. pharaonis features an MDR1 homologue that is induced by pollution and may serve as a sentinel organism for routine biomonitoring programs. However, our findings also exemplify that not all MDRs are equally suitable for this purpose and sequence information must be expanded beyond the ATPase domain for correct classification of cloned genes.

Fine structure of naive and allogeneic challenged ampullae in Botrylloides subpopulation I from the Mediterranean coast of Israel

The external peripheral termini of vasculature in botryllid ascidians (ampullae) are important in the expression of effector mechanisms during histocompatibility reactions. We study here morphological changes to the microstructure during allorecognition in Botrylloides subpopulation I (SP1) from the Mediterranean coast of Israel, where special giant ampullae, called megaloampullae are developed hours after first allogeneic challenge. The basal part of each naive ampulla consists of a sheath of continuous squamous epithelial cells (1 μm×20 μm). At the tip of the ampullae, about 130 epithelial cells become columnar with wide apical pads (15 μm×5–10 μm), that contain electron-opaque “adhesive vesicles”. Foci of crystallizations were observed within the vesicles of some columnar cells. Ampullar epithelial cells develop internal folds that support tight attachments between circulating blood cells (most of them are pigment cells) and ampullar epithelium. During the histoincompatibility process, the tunic peripheral edge at the interaction area becomes highly convoluted. Filaments (up to 1.16 μm) accumulate in the interaction tunic matrix. Some of these filaments encircle destructed cells. Fragmented cell membranes are also found next to the reacting ampullae. The most characteristic feature of the Botrylloides SP1 rejection reaction is dilation of the ampullae. The ampullar epithelium becomes “curly” when megaloampullae are formed. Within the curly region, about 30% of the squamous epithelial cells are further stretched, up to 33 μm in length. Some additional mechanisms are suggested to explain the fast increase (up to seven times) in ampullar width that is recorded within a few hours from the first allogeneic contact.

Development of Panel of Monoclonal Antibodies Specific to Urochordate Cell Surface Antigens

Monoclonal antibodies are an important tool in the study of botryllid ascidians' immunology and developmental biology. Here we describe the development of a panel of 38 monoclonal antibodies that are specific to Botryllus schlosseri (Ascidiacea; subfamily Botryllinae) cell surface antigens. Many of these hybridomas recognize (by enzyme-linked immunosorbent assay and immunohistochemistry) epitopes of Botrylloides subpopulations (SP) II and III from the Mediterranean coast of Israel and show, on blood cell smear assays, reactions with subsets of Botryllus circulating blood cells. Fluorescence-activated cell sorting analyses using antibodies positive for botryllid tissues revealed up to 3.6% positive cells. ELISA screenings were performed with 64 new monoclonal antibodies on 5 different individual botryllid ascidian colonies (B. schlosseri, Botrylloides). The positive antibodies in this panel identified a large number of different antigenic determinants, some of which distinguish Botryllus versus Botrylloides colonies, and other, different colonies within these two species, or different cell types within tissues, embryos, and buds of individual colonies. Only 21 monoclonal antibodies tested positive with all colonies. Cross-reactivity with at least one Botrylloides colony was recorded in 49 hybridomas that identified Botryllus cells. This wide panel of monoclonal antibodies is the first such detailed set of monoclonals available for studies on botryllid ascidians.

New records and rare occurrences of fish species from the Mediterranean coast of Israel

The present study reports the first record of Lagocephalus sceleratus and the first substantiated record of Bathophilus nigerrimus from the Mediterranean coast of Israel. Specimens of another four species, Mobula mobular, Tylosurus choram, Scarus ghobban and Tetrapturus belone, constitute second records from this region.

Coastal cliff retreat rates at Beit‐Yannay, Israel, in the 20th century

AbstractResearch indicates that the aeolianite (Kurkar) cliffs along the Israeli Mediterranean coastline have continuously retreated eastward during the last few decades. There seems to be no dispute among Earth scientists regarding the general trend of cliff retreat. However the majority of papers displaying cliff retreat rates are based upon comparison of aerial photographs. Their lack of advanced geometric measurement methods causes a high margin of error. Public attention is focused upon the Beit‐Yannay coastal cliff since private homes are located along the southern section of the cliff crest. The current research compares the historic location of the cliff crest edge at Beit‐Yannay as observed in a series of aerial photographs taken during the period 1918–2000. Quantitative measurement methods included applications of satellite geodesy and digital photogrammetry and mapping. Research results offer quantitative, consecutive and highly accurate data regarding retreat rates over a relatively long period of 82 years. It is concluded that: 1. Annual average cliff retreat rates of the cliff crest is 20 cm/year. 2. Categorization of the study time span reveals periods displaying varying retreat rates such as 27 cm/year during 1918–1946, 21 cm/year during 1946–1973 and 10 cm/year during 1973–2000. 3. Maximum retreat distances of the cliff crest, over the study period were found to be approximately 25 m along the northern, lowest section of the cliff. Minimum distances of 11 m were identified at the highest, southern section of the cliff. 4. The eolianite (Kurkar) cliffs along the Israeli Mediterranean coast throughout the 20th century have been an important source of sediment, contributing approximately 24 × 106 m3 of sediments to the sediment balance of Israeli beaches. Copyright © 2004 John Wiley & Sons, Ltd.

Radiocarbon in Porewater of Continental Shelf Sediments (Southeast Mediterranean)

In this study, we aim to characterize the main processes controlling 14CDIC concentrations in porewater at the shallow shelf (water depth less than 120 m) off the Mediterranean coast of Israel. At these water depths, we expected to find evidence for seawater penetration toward the coast, since this area was flooded by seawater only some 18,000 yr ago (the end of the Last Glacial period).Measurements of the chemical composition (14CDIC) and stable carbon isotopic composition (δ13CDIC) were performed in several sediment cores (40–250 cm long) at water depths between 6 and 115 m. At water depths of 60 m, represented by a 2.5-m-long sediment core, the porewater 14CDIC levels (85–87 pMC) were lower than the corresponding sediment values in each layer (92–95 pMC), mainly due to the oxidation of relatively old organic matter (about 70 pMC) with no evidence to advection. In contrast, sediment cores from water depths shallower than 50 m showed only slight anaerobic oxidation and high 14CDIC values of approximately 100 pMC, indicating possible downward advection. These geochemical observations support the perception that the penetration of seawater into the coastal aquifer occurs at the shallow water zone (<50 m), while further verification by deeper cores is required.

Quantitative evaluation of hepatic cytochrome P4501A transcript, protein, and catalytic activity in the striped sea bream (Lithognathus mormyrus).

Hepatic cytochrome P4501A (CYP1A) expression was partially characterized in the striped sea bream (Lithognathus mormyrus) from the Mediterranean coast of Israel as part of the process of establishing the CYP1A gene as an environmental biomarker. Reverse transcription-competitive polymerase chain reaction, competitive enzyme-linked immunosorbent assay, and ethoxyresorufin O-deethylase (EROD) assay were used for evaluating transcript, protein, and catalytic activity levels, respectively, in absolute units. Highest elucidated transcript, protein, and catalytic activity levels were 0.264 +/- SD 0.084 fmol/microg total RNA, 0.88 +/- 0.52 pmol/microg total protein, and 1.11 +/- 0.52 pmol resorufin/min/microg total protein, respectively, and the lower levels were 0.009 +/- 0.007 fmol/microg total RNA, 0.17 +/- 0.08 pmol/microg total protein, and 0.11 +/- 0.06 pmol resorufin/min/microg total protein, respectively, demonstrating substantial induction potential. All alternate pairs of seven examined field samples, revealing a transcript-level ratio higher than 1.7, also demonstrated a significant difference between their transcript levels, indicating a potential to detect relatively small biomarker changes (1.7-fold) caused by environmental effects. Simultaneous triple measurements of transcript, protein, and catalytic activity were carried out in individuals from two field samples and during a 318-d decay experiment. Fish from the field samples revealed significant alternate bivariate correlation between transcript, protein, and enzymatic activity. Conflicting results were found when analyzing the decay experiment, in which both protein and catalytic activity levels decreased significantly to basal levels, in contrast to no significant change in transcript levels throughout the experiment. No significant difference was observed between males and females regarding the levels of CYP1A transcript, protein, and EROD.

Marine molluscs in environmental monitoring

Concentrations of trace elements and organic pollutants were determined in marine sediments and molluscs from the Mediterranean and Red Sea coasts of Israel. Two bivalve species (Donax trunculus, Pteria aegyptia), two gastropod species (Patella caerulea, Cellana rota) and sediments were sampled at polluted and relatively clean, reference, sites. Along the Mediterranean coast of Israel, sediments and molluscs from Haifa Bay stations were enriched with both organic and trace element contaminants. In the Red Sea, differences between the polluted and reference sites were less pronounced. Bio-concentration factors indicate a significant concentration of Zn, As, Cd, Sn and Pb in animal tissue relative to the concentrations of these elements in the sediments. In contrast, Ce, La and U were not concentrated in molluscs. The trace element results indicate a saturation of the detoxification mechanisms in molluscs from polluted sites. The concentrations of organic pollutants at the same sites are at the lower range of values recorded in other studies. However, synergistic effects between these compounds and between them and metals can lead to acute toxicity.

Heavy metal levels in bottlenose and striped dolphins off the Mediterranean coast of Israel

Heavy metal levels in bottlenose and striped dolphins off the Mediterranean coast of Israel

Formation of parabolic dunes from barchan and transverse dunes along Israel's Mediterranean coast

AbstractThe Mediterranean coastal dunes of Israel underwent a land‐use change during the second half of the 20th century. Due to intense agricultural and pastoral activity, the coastal dunes were stripped of natural vegetation until the end of the first half of the 20th century. The barchan and transverse dunes were shaped by strong southwesterly winter winds. A decrease in human activity during the second half of the 20th century brought about a renewal of natural vegetation on the dune crest—the only area with neither erosion nor deposition. The establishment of vegetation on the crest changes the dynamics of these barchan and transverse dunes, so that not all of the sand eroded from the windward side is carried to the lee slip‐face; some is trapped by plants. Consequently, there is a change in the shape of the windward slope from convex to concave, and the dune gradually becomes parabolic. In this study we trace the morphodynamics of the dunes by analysing 12 sets of aerial photographs, which were taken from 1944 to 1995. The average rate of advance of 15 dunes has decreased from 3·4 m a−1to 1·9 m a−1, while the vegetation cover has increased from 4·3 to 17 per cent during this period. Copyright © 2002 John Wiley & Sons, Ltd.

Risso's dolphin ( Grampus griseus) stranding on the coast of Israel (eastern Mediterranean). Autopsy results and trace metal concentrations

The stranding of Risso's dolphin ( Grampus griseus) on the Mediterranean coast of Israel is reported in this study. High concentrations of trace metals (Hg, Cd, Zn, Fe and Se) were found in the various tissues analyzed, while Cu and Mn concentrations were naturally low. The specimen was found alive, but died a day later. The cause of death was attributed to bacterial bronchopneumonia in combination with endotoxemia, resulting in disseminated intravascular coagulation. Plastic bags found in its stomach contributed to the dolphin's poor physical condition. No connection was found between the high concentrations of trace metals in the internal organs and the cause of death. It is assumed that the high concentrations were a result of the high trophic level of this species, its diet and its advanced age. Anthropogenic influence could not be assessed due to the sparse database of trace metals for this species, in particular knowledge of the natural levels.

CONTRIBUTION TO THE KNOWLEDGE OF THE AMPHIPODA (CRUSTACEA) OF THE MEDITERRANEAN COAST OF ISRAEL

A total of 54,275 amphipod specimens, identified to 53 species, was collected between 1994 and 1999 off the Mediterranean coast of Israel at depths ranging from the intertidal to 27 m. Four species constitute new records for the Eastern Mediterranean Sea and 20 are newly recorded from the Israeli coast. The amphipod fauna is considerably impoverished compared with the western Mediterranean. Of the 98 species known from the Israeli coast, 55% have an Atlanto-Mediterranean distribution, 19% are Mediterranean endemics, 16% are cosmopolitan, and 5% have entered through the Suez Canal.

Fish Biodiversity in the Vermetid Reef Of Shiqmona (Israel)

Abstract. A study of the structure of the fish community associated with a vermetid reef at Shiqmona, Israel, revealed the highest fish biodiversity (36 species) of any habitat along the Mediterranean coast of Israel. Despite the prevalence of fish of Erythrean origin in the Levantine littoral, the benthic fish community at the site is entirely autochthonous. The families richest in members were the Blenniidae and the Gobiidae. Eighteen species are benthic, sixteen supra‐benthic and two pelagic.

Spatial trends in the chemical composition of sediments on the continental shelf and slope off the Mediterranean coast of Israel

In order to determine whether observed trends in total trace metal content were natural or due to anthropogenic inputs, major and trace elements were measured on three size fractions (fine sand (250–63 μm), silt and clay (<63 μm) and clay (<2 μm)) of sediment collected off the Mediterranean coast of Israel. Partitioning of trace metals into carbonate/exchangeable, iron oxide and residual phases for each grain size was also determined. The dominant source of particles was Nile derived material. There was a decrease in Fe/Al, Ti/Al and non-carbonate Mg/Al in the fine sand fraction, interpreted as a decrease in heavy minerals towards the north and an increase in K/Al due to increased feldspars and micas. There was a simultaneous increase in CaCO 3 both towards the north and onshore in all grain size fractions due to a northward increase in local biogenic fragments and river detritus. This is consistent with circulation and sediment transport models for the southeast Levantine basin. The background trend in trace metals corresponds to changes in mineralogy. While the fine sand fraction appeared free of contamination, in the finer fractions there is a significant enrichment of Zn, and Cd towards the north, which is not accounted for by changes in mineralogy. The sediments were also enriched in Cu, Zn and Cd near Tel Aviv and Hadera. The peaks near Tel Aviv may correspond to waste discharged through the Yarqon and an old sewage pipe, whilst near Hadera, the Alexander and Hadera Rivers and the terminal for a coal-fired power station may be the source of contamination. There was also clear evidence for contamination by Pb in the finest sediments. However, there was no enrichment in Pb around the point sources of the other trace metals, therefore it was concluded that the majority of Pb contamination was from the atmosphere. All trace metal contamination may be subject to ‘smearing’ by sediment transport, particularly in the clay fraction.

Fish Processing During the Early Holocene: A Taphonomic Case Study from Coastal Israel

Study of fish bones recovered from coastal archaeological sites requires careful taphonomic analysis in order to determine whether the fish bone assemblage is naturally or culturally derived, and how fish may have been processed by humans. We analysed a grey triggerfish (Balistes carolinensis) assemblage from Atlit-Yam, a submerged Pre-Pottery Neolithic site (8140–7550bp) off the Mediterranean coast of Israel, using multiple taphonomic criteria and quantitative analyses. The clumped distribution of remains, the high bone scatter frequency, the presence of a few burnt bones, the bones' state of fragmentation, the absence of a correlation between bone density and bone frequency, the low species diversity and wide range of body sizes represented, all point to a culturally derived assemblage. The high percentage of identifiable elements, the occurrence of most skeletal elements, and the virtual absence of branchial region bones, are compatible with fish gutted for immediate or later consumption, and incompatible with the expected of refuse. Cranial bones and first dorsal spines of large individuals were missing, apparently a result of size-dependent butchering methods. The emergent picture is of a pile of fish gutted and processed in a size-dependent manner, and then stored for future consumption or trade. This scenario suggests that technology for fish storage was already available, and that the Atlit-Yam inhabitants could enjoy the economic stability resulting from food storage and trade with mainland sites.