On the occurrence of the Bull Ray Pteromylaeus bovinus (Chondrichthyes: Myliobatidae) in the Amvrakikos Gulf, Greece

We document in this note the occurrence of the Bull Ray Pteromylaeus bovinus (Geoffroy St-Hilaire, 1817) (Chondrichthyes: Myliobatidae) in the Amvrakikos Gulf (eastern Ionian Sea), within a recently designated Wetlands National Park. Although distributional data for this species are scant, there is circumstantial evidence depicting the species as rare in Greece and the Mediterranean

First record of Pontian Monkey Goby, Neogobius fluviatilis (Pallas, 1814) in the Evros River (Greece); Is it an alien species?

The Pontian Monkey Goby,Neogobius fluviatilis (Pallas, 1814), was recorded for the first time in Greece in August 2011. Eight specimens were collected in the Greek-Turkish section of the Evros River, 65 kilometers upstream of its river-mouth. Although the species has been recently discovered in the Tundza, a tributary of the Evros in Bulgaria, it has never before been found in the Evros’ main stem.  Although the lower Evros has been poorly researched by ichthyologists, it is unlikely that a conspicuous medium-sized fish would go unnoticed in this river; and, it is therefore suggested to be a probable alien. However, since the Evros basin has had geological connections to the Marmara Sea and Black Sea in the past and it is immediately adjacent to native populations of N. fluviatilis, the species status is categorized as questionable until genetic and morphological studies are completed

Riparian woodland flora in upland rivers of Western Greece

Although natural riparian woodlands are an important feature that affects the quality of aquatic conditionsin streams and rivers, surveying riparian zone flora is rarely implemented in the Mediterraneancountries. We developed a rapid assessment method for gathering standardized plot-based woody flora andvegetation data from riparian woodlands. In 2005 we surveyed 218 streamside vegetation plots at 109 sitesin upland areas of four major rivers in mainland Greece (Alfios, Acheloos, Arachthos, and Aoos). Herewe describe the survey method and provide selected results from its initial implementation. The simplicityand effectiveness of this survey procedure supports the use of rapid site-based biodiversity surveys for riparianzones alongside aquatic status assessments

First record of the Tadpole Shrimp Triops cancriformis (Branchiopoda, Notostraca) in Cyprus

The presence of the large branchiopod Triops cancriformis (Bosc, 1801-1802) in Cyprus is reported for the first time. Triops cancriformis individuals were observed in the large temporary wetland of Paralimni Lake (Famagusta District, Cyprus) during the wet periods of 2013 and 2014. This finding extends the current knowledge of the species distribution in the eastern Mediterranean area, and stresses the ecological and conservation value of the unique habitat of Paralimni Lake. In addition, it highlights the need for carrying on further studies on the fauna of temporary pond habitats in Cyprus, and for better conservation management strategies for such EU priority habitats

Distribution patterns of fish assemblages in an Eastern Mediterranean intermittent river

The distribution patterns of fish assemblages within streams can provide insights for river type classifications and may warrant specific conservation actions. However, there is limited knowledge of how fish assemblages assort along a longitudinal axis in Mediterranean intermittent streams. Patterns in spatial and temporal distribution of fish communities were analysed in a Mediterranean intermittent river (Evrotas River) located in Southern Greece, hosting three endemic range restricted species of high conservation concern, during the period 2007−2009, with 80% of the river’s total length desiccating in the 2007 and 2008 droughts. The general trend was an increase in fish density and species richness along an upstream-downstream gradient. Fish assemblages from upstream to downstream were characterized by a decrease of the most rheophilic species (Squalius keadicus) and an increase of the most stagnophilic species (Tropidophoxinellus spartiaticus). Three river segments, characterized by a high degree of homogeneity were delineated. Habitat and environmental preferences for the studied fish species were identified, with elevation and low flowing habitats being the most important environmental factors affecting fish distribution patterns. The current study provides evidence that even in an intermittent river an assemblage pattern following a longitudinal gradient can be identified, mainly due to the lack of instream barriers that allows recolonization after flow resumption

Developing policy-relevant river fish monitoring in Greece: Insights from a nation-wide survey

A wide-ranging river fish survey was executed in the summer of 2009 as part of the preparatory actions for the establishment of a monitoring programme for the EU Water Framework Directive (WFD). This was the first extensive electrofishing campaign for WFD standardized bioassessment in Greece and the experience and insights gained are used here to provide a review of fish-based assessment conditions and requirements in this country. The survey sampled 85 sites on 25 rivers throughout mainland Greece, collecting 70 species of freshwater fish. Quantitative site-based assemblage data is used for taxonomic and ordination analyses revealing a strong biogeographic regionalization in the distribution of the ichthyofauna. The structural and spatial organisation of the fish fauna through the use of species-level and community-level data analyses is explored in three ecoregions where data was deemed sufficient. Transitions in community taxonomic composition among ecoregions were abrupt and concordant with geographical barriers and reflect the influence of historical biogeographic processes. Community-based analysis revealed a substantial degree of variation in quantitative attributes of the fish assemblages among ecoregions. Key conclusions of this work are: (a) the fish-based bioassessment system must be regionalised to reflect biogeographic variation, (b) high faunal heterogeneity among ecoregions (taxonomic, structural), and to a lower degree among basins, constrain the transferability of bioassessment metrics and indices created for explicit regions to other regional frameworks; (c) faunal depauperation in most of the study areas reduce the utility of functional bioassessment metrics and also limits the utilization of rare species and the applicability of the classical form of the “Index of Biotic Integrity” concept. Recommendations to cope with these problems are discussed

Recent contributions to the distribution of the freshwater ichthyofauna in Greece

In this paper we supplement Greece’s recent annotated inventory of freshwater fishes per hydrographic basin with recent distributional data and taxa alteration information, based on field sampling and a literature review up to September 2011. We report on newly documented distributional records of 31 fish species plus one unidentified taxon, within 35 hydrographic river basin units in Greece. These new records include 14 native fish species, seven alien and 12 translocated. Translocated taxa are distinguished from aliens, in order to report species non-indigenous to a basin but native within the same ecoregion. Twelve hydrographic basin units are newly added to the roster of ichthyologically explored river basins following a previous basin-scale inventory method (the total is now 117). This review increases the number of Greece’s freshwater fish taxa to 167, since four new species are added to the list (Carassius langsdorfii, Neogobius fluviatilis, Telestes alfiensis, Millerigobius macrocephalus) and two are deleted (Salmo dentex, Barbus rebeli) due to taxonomic changes. Taxonomic changes will probably continue to alter the national list since phylogenetic research is ongoing on several taxa in many parts of the countr

Determination of environmental flows in rivers using an integrated hydrological-hydrodynamic-habitat modelling approach

[EN] We propose the novel integrated modelling procedure 3H-EMC for the determination of the environmental flow in rivers and streams; 3H-EMC combines Hydrological, Hydrodynamic and Habitat modelling with the use of the Environmental Management Classes (EMCs) that are defined by the Global Environmental Flow Calculator. We apply 3H-EMC in the Sperchios River in Central Greece, in which water abstractions for irrigation cause significant environmental impacts. Calculations of the hydrodynamic-habitat model, in which the large and the small chub are the main fish species, suggest discharge values that range from 1.0 m3/s to 4.0 m3/s. However, hydrological modelling indicates that it is practically difficult to achieve discharges that are higher than approximately 1.0-1.5 m3/s. Furthermore, legislation suggests significantly lower values (0.4-0.5 m3/s) that are unacceptable from the ecological point of view. This behaviour shows that a non-integrated approach, which is based only on hydrodynamic-habitat modelling does not necessarily result in realistic environmental flows, and thus an integrated approach is required. We propose the value of 1.0 m3/s as the "optimum" environmental flow for Sperchios River, because (a) it satisfies the habitat requirements, as expressed by the values of weighted useable area that are equal to 2180 and 1964 m2 for the large and small chub, respectively, and correspond to 82 and 95% of their respective maximum values, (b) it is consistent with the requirements of Environmental Classes A and B, whose percentiles are higher than 75% for discharge (77.2%) and for habitat availability (>83.5% for the large chub and >85.0% for the small chub), (c) it is practically achievable from the hydrological point of view, and (d) it is higher than the value proposed by the Greek legislation. The proposed modelling approach can be applied to any river or stream using the same or similar modelling tools, which should be linked via suitable coupling algorithms.Hydraulic field measurements were performed within the framework of a research project by the Hellenic Centre of Marine Research (HCMR) entitled KRIPIS “Development of an integrated management system for river basin, coastal and marine zones” (http://imbriw.hcmr.gr/en/). Fish habitat data were collected within the framework of the ECOFLOW research project (www. ecoflow.gr). A part of the modelling work has been performed, while the first author was a visiting professor at the Technical University of Munich (TUM); thanks are due to the Bavarian State Ministry of Education and Cultural Affairs and the German Academic Exchange Service (DAAD).Stamou, A.; Polydera, A.; Papadonikolaki, G.; Martinez-Capel, F.; Muñoz Mas, R.; Papadaki, C.; Zogaris, S.... (2018). Determination of environmental flows in rivers using an integrated hydrological-hydrodynamic-habitat modelling approach. Journal of Environmental Management. 209:273-285. https://doi.org/10.1016/j.jenvman.2017.12.038S27328520

Potential impacts of climate change on flow regime and fish habitat in mountain rivers of the southwestern Balkans

The climate change in the Mediterranean area is expected to have significant impacts on the aquatic ecosystems and particular in the mountain rivers and streams that often host important species such as the Salmo farioides, Karaman 1938. These impacts will most possibly affect the habitat availability for various aquatic species resulting to an essential alteration of the water requirements, either for dams or other water abstractions, in order to maintain the essential levels of ecological flow for the rivers. The main scope of this study was to assess potential climate change impacts on the hydrological patterns and typical biota for a south-western Balkan mountain river, the Acheloos. The altered flow regimes under different emission scenarios of the Intergovernmental Panel on Climate Change (IPCC) were estimated using a hydrologicalmodel and based on regional climate simulations over the study area. The Indicators of Hydrologic Alteration (IHA) methodology was then used to assess the potential streamflow alterations in the studied river due to predicted climate change conditions. A fish habitat simulation method integrating univariate habitat suitability curves and hydraulic modeling techniques were used to assess the impacts on the relationships between the aquatic biota and hydrological status utilizing a sentinel species, the West Balkan trout. The most prominent effects of the climate change scenarios depict severe flow reductions that are likely to occur especially during the summer flows, changing the duration and depressing the magnitude of the natural low flow conditions. Weighted Usable Area-flow curves indicated the limitation of suitable habitat for the native trout. Finally, this preliminary application highlighted the potential of science-based hydrological and habitat simulation approaches that are relevant to both biological quality elements (fish) and current EUWater policy to serve as efficient tools for the estimation of possible climate change impacts on the south-western Balkan river ecosystems.This study was supported by the ECOFLOW project funded by the Hellenic General Secretariat of Research and Technology in the framework of the NSRF 2007-2013. The W. B. trout data collection was partially funded by the Spanish Ministry of Economy and Competitiveness with the project SCARCE (Consolider-Ingenio 2010 CSD2009-00065).Papadaki, C.; Soulis, K.; Muñoz Mas, R.; Martinez-Capel, F.; Zogaris, S.; Ntoanidis, L.; Dimitriou, E. (2016). Potential impacts of climate change on flow regime and fish habitat in mountain rivers of the southwestern Balkans. Science of the Total Environment. 540:418-428. https://doi.org/10.1016/j.scitotenv.2015.06.134S41842854