Konstantinos Tsagarakis

Dr. Konstantinos Tsagarakis

orcid

Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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5 June 2013 in ICES Journal of Marine Science
Verified
Journal Article
Open access
PDF file
Konstantinos TsagarakisKonstantinos Tsagarakis
Konstantinos Tsagarakis
APA. Palialexis
A. Palialexis
VVV. Vassilopoulou
V. Vassilopoulou
A considerable amount of the existing knowledge of discards in the Mediterranean Sea is presented. Discarding highly varies along the basin both geographically and among the different fishing gears with bottom trawls being responsible for the bulk of discards, since they are characterized by high discards ratios. Midwater trawls, purse-seines, and small-scale fisheries, despite their less proportion of discards per se, produce overall high discards quantities, since they are responsible for the majority of the landings. Based on the collected information, a rough Mediterranean-wide estimate of discards around 230 000 t or 18.6% (13.3–26.8%) of the catch is produced. Discarding in the Mediterranean is regulated by market demands rather than by legal constraints, and marketable bycatch may constitute an important supplemental source of income. A pattern in resource use related to socio-cultural characteristics is apparent, with welfare communities discarding more in terms of percentages. Natural conditions (e.g. environmental gradients) and fishers' strategies also substantially affect discarding. Mitigation tools mainly comprise selectivity improvement and spatio-temporal closures. Despite the progress in studying discards, needs are evident to expand monitoring schemes, apply analytical techniques, and establish objectives of the discards issue under the framework of ecosystem approach to fisheries.

23 November 2012 in Fisheries Oceanography
Verified
Journal Article
Closed access
PDF file
MGMarianna Giannoulaki
Marianna Giannoulaki
MIM. Iglesias
M. Iglesias
MTM. P. Tugores
M. P. Tugores
ABAngelo Bonanno
Angelo Bonanno
BPB. Patti
B. Patti
VVV. Valavanis
V. Valavanis

1 January 2016 in Ecological Indicators
Verified
Journal Article
Closed access
MCM. Coll
M. Coll
LSL.J. Shannon
L.J. Shannon
KKK.M. Kleisner
K.M. Kleisner
MJM.J. Juan-Jordá
M.J. Juan-Jordá
ABA. Bundy
A. Bundy
YSY.-J. Shin
Y.-J. Shin

1 June 2010 in Estuarine, Coastal and Shelf Science
Verified
Journal Article
Closed access
Konstantinos TsagarakisKonstantinos Tsagarakis
Konstantinos Tsagarakis
MCM. Coll
M. Coll
MGM. Giannoulaki
M. Giannoulaki
SSS. Somarakis
S. Somarakis
CPC. Papaconstantinou
C. Papaconstantinou
AMA. Machias
A. Machias

20 December 2011 in Marine Ecology Progress Series
Verified
Journal Article
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MTMaria Pilar Tugores
Maria Pilar Tugores
MGMarianna Giannoulaki
Marianna Giannoulaki
MIMagdalena Iglesias
Magdalena Iglesias
ABAngelo Bonanno
Angelo Bonanno
VTVjekoslav Tičina
Vjekoslav Tičina
VVVasilis Valavanis
Vasilis Valavanis
Integrated information from different parts of the Mediterranean Sea was used to model the spatial and temporal variability of the distribution grounds of the sardine population. Acoustic data from the North Aegean Sea (Eastern Mediterranean), the Adriatic Sea (Central Mediterranean), the Sicily Channel (Central Mediterranean) and Spanish Mediterranean waters (Western Mediterranean) were analysed along with satellite environmental and bathymetric data to model the potential habitat of sardine during summer, autumn and early winter. Generalized additive models were applied in a presence−absence approach. Models were validated in terms of their predictive ability and used to construct maps exhibiting the probability of sardine presence throughout the entire Mediterranean basin as a measure of habitat adequacy for sardine. Bottom depth and sea surface temperature were the environmental variables that explained most of the data variability. Several areas along the Mediterranean coastline were indicated as suitable habitat for sardine in different seasons. An expansion of these areas over the continental shelf, up to 100 m depth, was consistently noticed from summer to winter. This was attributed to the horizontal movements of sardine related to spawning (i.e. winter period) and the peculiarities of the Mediterranean Sea where areas favouring growth, feeding and spawning processes tend to be localised and prevent a long range, offshore migration as opposed to large upwelling ecosystems. Moreover, within the study period, a positive relationship between the extent of sardine preferred habitat and landings was revealed for both summer and winter seasons throughout the entire Mediterranean SeaPublicado

20 September 2016 in Fish and Fisheries
Verified
Journal Article
Open access
PDF file
ABAlida Bundy
Alida Bundy
RCRatana Chuenpagdee
Ratana Chuenpagdee
JBJennifer L Boldt
Jennifer L Boldt
MBMaria de Fatima Borges
Maria de Fatima Borges
MCMohamed Lamine Camara
Mohamed Lamine Camara
YSYunne‐Jai Shin
Yunne‐Jai Shin
Fisheries have had major negative impacts on marine ecosystems, and effective fisheries management and governance are needed to achieve sustainable fisheries, biodiversity conservation goals and thus good ecosystem status. To date, the IndiSeas programme (Indicators for the Seas) has focussed on assessing the ecological impacts of fishing at the ecosystem scale using ecological indicators. Here, we explore fisheries ‘Management Effectiveness’ and ‘Governance Quality’ and relate this to ecosystem health and status. We developed a dedicated expert survey, focused at the ecosystem level, with a series of questions addressing aspects of management and governance, from an ecosystem‐based perspective, using objective and evidence‐based criteria. The survey was completed by ecosystem experts (managers and scientists) and results analysed using ranking and multivariate methods. Results were further examined for selected ecosystems, using expert knowledge, to explore the overall findings in greater depth. Higher scores for ‘Management Effectiveness’ and ‘Governance Quality’ were significantly and positively related to ecosystems with better ecological status. Key factors that point to success in delivering fisheries and conservation objectives were as follows: the use of reference points for management, frequent review of stock assessments, whether Illegal, Unreported and Unregulated (IUU) catches were being accounted for and addressed, and the inclusion of stakeholders. Additionally, we found that the implementation of a long‐term management plan, including economic and social dimensions of fisheries in exploited ecosystems, was a key factor in successful, sustainable fisheries management. Our results support the thesis that good ecosystem‐based management and governance, sustainable fisheries and healthy ecosystems go together.