The present study assesses maturity and reproductive dynamics of pufferfish Lagocephalus sceleratus (Gmelin, 1789) off Cyprus (southeastern Mediterranean Sea), in relation to regional differences in oceanographic conditions, habitat characteristics and fishing activity. In addition, the allometric pattern of gonadal growth was studied to validate the use of the gonadosomatic index (GSI) in assessments of the reproductive cycle. To do so, 4743 pufferfish were sampled between May and October 2010 so as to cover the reproductive period of the population, which peaks from late spring to middle summer. Analysis of GSI data showed a clear differentiation between 2 pufferfish populations residing in the southwestern (SWA) and the south-east (SEA) coastal areas of Cyprus. Specifically, the SWA population was mainly dominated by immature individuals and exhibited a more delayed and narrow reproductive period. Moreover, generalized linear model analysis (GLM) showed that the SWA population exhibited significantly smaller size at 50% maturity, L 50 (41.9 cm), compared to the SEA population (48.8 cm). These differences in reproductive seasonality and L 50 were not found to be related to differences in sea surface temperature (SST) between the 2 regions, whilst mature individuals almost entirely disappeared from both areas outside the reproductive period. The latter could not be attributed to overfishing of the larger size classes since the fishery was not shown to be selective to pufferfish size. These results indicate that L. sceleratus may be a spawning migratory species that visits Cyprus southeastern coasts to reproduce and then migrates to other warm areas of the eastern Levantine basin.

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The degree of development and operability of the indicators for MSFD using Descriptor 1 (D1)Biological

Within the COST action EMBOS (European Marine Biodiversity Observatory System) the degree and variation of the diversity and densities of soft-bottom communities from the lower intertidal or the shallow subtidal was measured at twenty-eight marine sites along the European coastline (Baltic, Atlantic, Mediterranean) using jointly-agreed and harmonised protocols, tools and indicators. The hypothesis tested was that the diversity for all taxonomic groups would decrease with increasing latitude. The EMBOS system delivered accurate and comparable data on the diversity and densities of the soft sediment macrozoobenthic community over a large-scale gradient along the European coastline. In contrast to general biogeographic theory, species diversity showed no linear relationship with latitude, yet a bell-shaped relation was found.The diversity and densities of benthos were mostly positively correlated with environmental factors such as temperature, salinity, mud and organic matter content in sediment, or wave height, and related with location characteristics such as system type (lagoons, estuaries, open coast) or stratum (intertidal, subtidal).For some relationships, a maximum (e.g. temperature from 15 to 20 °C; mud content of sediment around 40 %) or bimodal curve (e.g. salinity) was found. In lagoons the densities were twice higher than in other locations, and at open coasts the diversity was much lower than in other locations. We conclude that latitudinal trends and regional differences in diversity and densities are strongly influenced by, i.e. merely the result of, particular sets and ranges of environmental factors and location characteristics specific to certain areas, such as the Baltic, with typical salinity clines (favouring insects) and the Mediterranean, with higher temperatures (favouring crustaceans). Therefore, eventual trends with latitude are primarily indirect and so can be overcome by local variation of environmental factors.

Examining how variability in population abundance and distribution is allotted among different spatial scales can inform of\ud processes that are likely to generate that variability. Results of studies dealing with scale issues in marine benthic communities suggest that variability is concentrated at small spatial scales (from tens of centimetres to few metres) and that spatial patterns of variation are consistent across ecosystems characterized by contrasting physical and biotic conditions, but this has not been formally tested. Here we quantified the variability in the distribution of intertidal rocky shore communities at a range of spatial scales, from tens of centimetres to thousands of kilometres, both in the NE Atlantic and the Mediterranean, and tested whether the observed patterns differed between the two basins. We focused on canopy-forming macroalgae and associated understorey assemblages in the low intertidal, and on the distribution of Patella limpets at mid intertidal levels. Our results highlight that patterns of spatial variation, at each scale investigated, were consistent between the Atlantic and the Mediterranean, suggesting that similar ecological processes operate in these regions. In contrast with former studies, variability in canopy cover, species richness and limpet abundance was equally distributed among spatial scales, possibly reflecting the fingerprint of multiple processes. Variability in community structure of low intertidal assemblages, instead, peaked at the largest scale, suggesting that oceanographic processes and climatic gradients may be important. We conclude that formal comparisons of variability across scales nested in contrasting systems are needed, before any generalization on patterns and processes can be made