|
|
|
|
|
Tserpes, George; Massutí, Enric; Fiorentino, Fabio; Facchini, Maria Teresa; Viva, Claudio; Jadaud, Angelique; Joksimovic, Aleksandar; Pesci, Paola; Piccinetti, Corrado; Sion, Letizia; Thasitis, Ioannis; Vrgoc, Nedo. |
The present work examines the spatio-temporal biomass trends of Mullus barbatus and Mullus surmuletus in the Mediterranean Sea through the analysis of a time series of data coming from the Mediterranean International Trawl Surveys (MEDITS), accomplished annually from 1994 to 2015. The biomass of both species showed clear declining trends below 150 to 200 m depth, which were steeper in the case of M. barbatus. Increases in temporal biomass trends were observed for M. barbatus from 2008 onward in most geographic sub-areas (GSAs), while stability was mostly observed for M. surmuletus. For both species, dynamic factor analysis revealed similarities among neighbouring GSAs and the subsequent cluster analysis identified two major GSA groups corresponding to the... |
Tipo: Text |
Palavras-chave: Red mullet; Striped red mullet; Distribution; Trends; Mediterranean. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00489/60056/63336.pdf |
| |
|
|
Carbonara, Pierluigi; Zupa, Walter; Anastasopoulou, Aikaterini; Bellodi, Andrea; Bitetto, Isabella; Charilaou, Charis; Chatzispyrou, Archontia; Elleboode, Romain; Esteban, Antonio; Follesa, Maria Cristina; Isajlovic, Igor; Jadaud, Angelique; Garcia-ruiz, Cristina; Giannakaki, Amalia; Guijarro, Beatriz; Kiparissis, Sotiris Elias; Ligas, Alessandro; Mahe, Kelig; Massaro, Andrea; Medvesek, Damir; Mytilineou, Chryssi; Ordines, Francesc; Pesci, Paola; Porcu, Cristina; Peristeraki, Panagiota; Thasitis, Ioannis; Torres, Pedro; Spedicato, Maria Teresa; Tursi, Angelo; Sion, Letizia. |
The uncertainty in age estimation by otolith reading may be at the root of the large variability in red mullet (Mullus barbatus) growth models in the Mediterranean. In the MEDITS survey, red mullet age data are produced following the same sampling protocol and otolith reading methodology. However, ageing is assigned using different interpretation schemes, including variations in theoretical birthdate and number of false rings considered, in addition to differences in the experience level of readers. The present work analysed the influence of these variations and the geographical location of sampling on red mullet ageing using a multivariate approach (principal component analysis). Reader experience was the most important parameter correlated with the... |
Tipo: Text |
Palavras-chave: Mullus barbatus; Age variability; MEDITS; Mediterranean; Reader effect; False rings; Date of birth. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00591/70320/68356.pdf |
| |
|
|
Peristeraki, Panagiota; Bitetto, Isabella; Carbonara, Pierluigi; Carlucci, Roberto; Certain, Gregoire; De Carlo, Francesco; Gristina, Michele; Kamidis, Nikos; Pesci, Paola; Stagioni, Marco; Valls, María; Tserpes, George. |
Mean temperature (MTC) and mean trophic level (MTL) spatiotemporal patterns of MEDITS survey catches were examined in 13 geographic statistical areas (GSAs) of the Mediterranean between 1994 and 2016. The study aimed to detect changes in the demersal community structure related to anthropogenic impacts. A generalized additive modelling approach was used to examine the effects of year and GSA on the MTC and MTL indexes and on bottom temperature by haul. For the MTC index, the year was significant only in 4 GSAs, while for MTL it was significant in 5. Higher MTC values were observed in central and eastern areas. Bottom temperature increased after 2010, and also from west to east and from north to south. Our results indicate that the recently observed... |
Tipo: Text |
Palavras-chave: Mean temperature of the catch; Trophic level; Bottom temperature; Trends; Mediterranean; Fishing pressure; Sea warming; Climate change. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00489/60054/63332.pdf |
| |
|
|
Bitetto, Isabella; Romagnoni, Giovanni; Adamidou, Angeliki; Certain, Gregoire; Di Lorenzo, Manfredi; Donnaloia, Marilena; Lembo, Giuseppe; Maiorano, Porzia; Milisenda, Giacomo; Musumeci, Claudia; Ordines, Francesc; Pesci, Paola; Peristeraki, Panagiota; Pesic, Ana; Sartor, Paolo; Spedicato, Maria Teresa. |
The state of marine systems subject to natural or anthropogenic impacts can be generally summarized by suites of ecological indicators carefully selected to avoid redundancy. Length-based indicators capture the status of fish community structure, fulfilling the Marine Strategy Framework Directive (MSFD) requirement for Descriptor 3 (status of commercial fish species). Although the MSFD recommends the development of regional indicators, a comparison among alternative length-based indicators is so far missing for the Mediterranean Sea. Using principal component analysis and dynamic factor analysis, we identified the most effective subset of length-based indicators, whether or not based on maximum length. Indicator trends and time series of fishing effort and... |
Tipo: Text |
Palavras-chave: Demersal fish community; Size structure indicators; Geographical sub-area; Marine Strategy Framework Directive; Dynamic factor analysis; Redundancy analysis. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00599/71148/69466.pdf |
| |
|
|
|