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Ecological restoration is an important tool to reverse habitat loss and recover ecosystem services. Here, for two years, we examine the dynamic of Posidonia oceanica following the restoration of a 1149 m

Polychaetes inhabit all the marine benthic communities and play a significant role in the degradation of calcareous substrates in marine environment. Colonization dynamics of encrusting epibenthos and polychaete assemblages on limestone experimental substrates were studied over a 3-year period in a Marine Protected Area: the Underwater Archaeological Park of Baiae (central Tyrrhenian Sea). Competitive and encrusting organisms replaced the pioneer species, dominating the epilithic community, and increasing the available surface. Polychaetes increased in species number over time. Several boring specimens of the species Polydora ciliata and Dodecaceria concharum were responsible for the bioerosion of the calcareous material. The former species characterized the early stage of the succession, whereas the latter settled during the late stages, together with the nestler species Lysidice unicornis, whose boring activity has been hypothesized. Four different surface trace morphologies attributable to boring polychaetes are here reported and described. The number of the polychaete boring traces increased according to the surface covered by ascidians, barnacles, and bryozoans. The present work provides evidence regarding positive interactions between encrusting epibenthic organisms and endolithic worms.

Soft-bottom benthic communities were studied along the Western coast of the Ligurian Sea with a new approach using both videocamera surveys and collected samples. The preliminary distribution of soft-bottoms and the definition of the limits and status of seagrass beds were carried out in September 1991, using an underwater vehicle provided with a videocamera and towed by a boat. Moreover, 90 benthic samples were collected at 5-40 m depth in order to characterize the macrobenthic soft-bottom communities. Six soft-bottom benthic assemblages and two sea grass biotopes (Cymodocea nodosa and Posidonia oceanica) were revealed by means of underwater images and multivariate analysis (TWINSPAN) on samples collected. The communities inhabiting the infralittoral sandy and coarse sediments corresponded to those previously described in the Mediterranean Sea, whereas a large complex transition between sandy and muddy communities was recognized on circalittoral soft-bottoms. Information obtained with this approach was used to draw a map of the investigated areas at 1:10,000 scale. The employment of the two techniques was cost effective for both time and research effort. Las comunidades bentónicas de fondos blandos se estudiaron a lo largo de la costa oeste del Mar de Liguria con una nueva aproximación, utilizando videocámaras y tomando muestras. La distribución de los fondos blandos así como la definición de los límites y estados de las praderas se realizaron en Septiembre de 1991, utilizando un vehículo submarino provisto de una videocámara y remolcado con un bote. Aproximadamente unas 90 muestras fueron recolectadas entre 5 y 40 m de profundidad para caracterizar las comunidades macrobentónicas de fondos blandos. Las imágenes submarinas y los resultados del análisis multivariante (TWINSPAN) aplicado sobre las muestras recolectadas revelaron seis agregaciones bentónicas de sustrato blando y dos biotopos de pradera (Cymodocea nodosa y Posidonia oceanica). Las comunidades que habitan el infralitoral arenoso y de sedimento grueso se corresponden con las previamente descritas en el Mediterráneo, no obstante, se reconoce una compleja transición entre las comunidades de arenas y de fangos en los fondos blandos circalitorales. La información obtenida mediante esta aproximación fue utilizada para configurar un mapa de las áreas estudiadas a escala 1:10.000. La utilización de ambas técnicas fue rentable en términos de tiempo y esfuerzo invertidos.

Hake recruitment has been examined in relation to environmental variables in two of the main reproductive areas of the central Mediterranean, the northern and central Tyrrhenian Sea. Seventeen years time series data from trawl surveys revealed high fluctuations in recruit abundance that could not be just explained by spawning biomass estimations. Generalized additive models were developed to investigate hake recruitment dynamics in the Tyrrhenian Sea in relation to spawner abundance and selected key oceanographic variables. Environmental data were explored in attempt to explain survival processes that could affect early life history stages of hake and that accounted for high fluctuations in its recruitment. Thermal anomalies in summer, characterised by high peaks in water temperature, revealed a negative effect on the abundance of recruits in autumn, probably due to a reduction in hake egg and larval survival rates. In the northern Tyrrhenian, recruitment was reduced when elevated sea-surface temperatures were coupled with lower levels of water circulation. Enhanced spring primary production, related to late winter low temperatures could affect water mass productivity in the following months, thus influencing spring recruitment. In the central Tyrrhenian a dome-shaped relationship between wind mixing in early spring and recruitment could be interpreted as an “optimal environmental window” in which intermediate water mixing level played a positive role in phytoplankton displacement, larval feeding rate and appropriate larval drift. Results are discussed in relation to the decline in hake stock biomass and within the present climate change and global warming context.

We investigated daily ration, feeding rhythms and gastric evacuation rates of juvenile (Merluccius merluccius, using stomach samples collected during four 24-hour trawl surveys carried out in 2001–2002 on the continental shelf-break (from 120 m to 160 m in depth) off the western coast of central Italy (central Mediterranean Sea). In each survey 8 hauls of 30 minutes were performed every three hours throughout the 24-hour period to cover the entire diel cycle. Diet of juvenile hake was mostly composed of the euphausiid Nyctiphanes couchii, showing a peak in stomach contents during early morning followed by a daytime decrease. Fullness index (%FI) was generally higher during sunrise when migratory activity ceased and juvenile hake return to the bottom after feeding. Concerning the hake abundance the highest density value was obtained in May during the recruitment period.Two independent daily ration estimates were produced. First, an empirical attempt to estimate the daily amount of food consumed was obtained by back-calculating the fresh weight of euphausiid prey ingested by juvenile hake. Estimated values ranged from 4.96–5.89% body wet weight (%BW). Second, the daily ration was computed applying the exponential gastric evacuation models proposed by Elliot & Persson (1978) and Eggers (1979). Daily ration values obtained using these consumption models produced a considerable (15–20%) underestimation of consumption rate for juvenile hake.

The sexual maturation and the growth of the salema, Sarpa salpa (Linnaeus, 1758), along the Italian Mediterranean coast (central Italy), were studied in fish (n = 105) killed incidentally by underwater explosions during the construction of Civitavecchia harbour in 1999 and specimens collected with trammel nets (n = 339). This species is characterized by a protandric hermaphroditism and the sex change process occurs between 24 and 31 cm TL corresponding to a wide range of ages (3-7 years). Size at maturity (L50) was 19.5 cm, at which almost all the individuals were males. Two distinct spawning periods were observed: one in spring, from March to May, and the other in autumn, from the end of September to November. During the first year, compensatory growth occurred in the individuals born in the two periods. An annual regular pattern of ring deposition was identified in the otoliths: the translucent ring was laid down during the winter months, while the opaque ring was formed during the summer months. Back-calculated lengths at age were used to estimate the parameters of the Von Bertalanffy growth equation which were: L∞ = 37.27 cm, K = 0.27 year-1 and t0 = -0.53 year. Salema showed isometric growth (b = 3.04; P = 0.84; t = 0.19). La maduración sexual y crecimiento de Sarpa salpa (Linnaeus, 1758) en las costas del Mediterráneo italiano (Italia central) fueron estudiadas a partir de la recolecta de ejemplares muertos accidentalmente (n = 105) como consecuencia de las explosiones submarinas acaecidas durante la construcción del puerto de Civitavecchia en 1999, así como de ejemplares recolectados mediante redes de arrastre (n = 339). Esta especie se caracteriza por un hermafroditismo protándrico, ocurriendo el proceso de cambio sexual entre los 24 y 31 cm TL, los cuales corresponden a un amplio rango de edades (3-7 años). La talla de maduración (L50) fue de 19,5 cm, siendo la casi la totalidad de los individuos eran de sexo masculino. Se observaron dos períodos diferentes de reproducción: uno en primavera, de marzo a mayo y otro en otoño, de finales de septiembre a noviembre. Se observó, durante el primer año, un crecimiento compensatorio ocurrido entre los individuos nacidos en los dos períodos. Se identificó en los otolitos un modelo anual y regular de deposición de anillos. Se observó el depósito de un anillo translúcido durante los meses invernales, mientras que otro opaco se formó durante los meses de verano. Las composición por edades y tallas retrocalculadas se utilizaron para estimar los parámetros de la ecuación de crecimiento de Von Bertalanffy, es decir: L∞ = 37,27 cm, K = 0,27 año-1 y t0 = -0,53 año. S. salpa demostró un crecimiento isométrico (b = 3,04; P = 0,84; t = 0,19).

Abnormal splanchnic circulation (ASC) is often detected too late, when hepatic circulation is already irreversibly compromised. If we could detect surgical or metabolic problems early after graft reperfusion, we might be able to correct them immediately before the damage becomes irreversible. The aim of this study was to determine if ASC can be predicted early after liver transplantation (LT) using portal vein pressure measurements and graft oxygen consumption monitoring. Patients and methods Twenty-patients (13 men, 7 women of mean age 46 years) undergoing LT with the piggyback technique for hepatitis C virus (HCV)/hepatitis B virus (HBV)-related cirrhosis were retrospectively divided in two groups. Group A (16 patients), in which LT was successful, and group B (4 patients) in which LT was unsuccessful because of primary nonfunction (2 patients), infrahepatic portal vein thrombosis (1 patient), or hepatic vein kinking (1 patient). We then compared the portal blood pressure values and the prehepatic and posthepatic oxygen content difference (p-pDO 2 ) before portal clamping; at the end of anhepatic phase; 5, 15, and 25 minutes after portal vein (PV) reperfusion; and 5, 20, 40, and 100 minutes after hepatic artery anastomosis. Results Early after graft reperfusion; portal pressure decreased to levels lower than that at baseline in group A, but remained high until the end of surgery in group B. At the end of surgery, p-pDO 2 increased more among group B than group A. Conclusion ASC, specifically an increased PV resistance, can be predicted early after LT by portal vein pressure measurements and graft oxygen consumption monitoring.

Mediterranean razorfish, Xyrichthys novacula, were collected between July and December in a sandy bay of Ponza Island (Central Mediterranean Sea) to investigate the effects of reproduction and growth patterns on sexual inversion processes and haremic territoriality. The minimum body size of males decreased from 17 cm in July to 15 cm (T.L.) in October as a consequence of the sexual inversion after reproduction. Females showed a reproductive peak in August using both the Holden and Rait scale and the gonodosomatic index. The gonads of males were small, on average only 0.14% of total body weight. The proportion of body weight devoted to gonads did not change with male size. This is probably a consequence of the haremic mating system of the species which reduces sperm competition between males. A new coloration phase for females was introduced in addition to the three already described in the literature. Individuals of each age class are characterised by different coloration patterns. This chromatic feature of the species allows dominant males to recognize the age of females and consequently to choose during harem formation the older and larger specimens able to produce a larger number of offspring., No disponible