No file available
To read the file of this research,
you can request a copy directly from the authors.
ResearchGate has not been able to resolve any citations for this publication.
15 μέτρων. Στην εργασία προτείνεται μέθοδος επεξεργασίας των πρωτογενών δεδομένων ΣΠΣ για την εκτίμηση της αλιευτικής προσπάθειας. Η μέθοδος εφαρμόστηκε στο στόλο μηχανότρατας και γριγρί και έγιναν μηνιαίες εκτιμήσεις της αλιευτικής προσπάθειας ανά κατηγορία αλιείας. Τα χαρτογραφικά υπόβαθρα υψηλής ανάλυσης που παράχθηκαν αναδεικνύουν τα αλιευτικά πεδία της μηχανότρατας και του γριγρί της Ελλάδας, την πίεση που ασκείται σε αυτά και τις στρατηγικές μετακίνησης του αλιευτικού στόλου χωρικά και χρονικά. Από τα αποτελέσματα προκύπτει ότι η περιοχή του Β. Αιγαίου είναι το σημαντικότερο αλιευτικό πεδίο της χώρας συγκεντρώνοντας το 32% της ετήσιας αλιευτικής προσπάθειας της μηχανότρατας και το 42% του γριγρί. Στο Αιγαίο η αλιευτική προσπάθεια αντιπροσωπεύει το 88.3% για τη μηχανότρατα και το 90.2% για το γριγρί, ενώ στο Ιόνιο οι αντίστοιχες τιμές είναι 11.7% και 9.8%. Ερευνητικά κέντρα και διαχειριστικοί φορείς χρησιμοποιώντας τα αποτελέσματα της ανάλυσης δεομένων ΣΠΣ έχουν τη δυνατότητα προβλέψεων και κατασκευής σεναρίων για τον έλεγχο της αλιευτικής προσπάθειας, καθώς και την εκπόνηση σχεδίων για την αειφόρο διαχείριση των αποθεμάτων. Λέξεις κλειδιά: Αλιευτική πίεση, χωροχρονική κατανομή αλιευτικού στόλου, χαρτογράφηση αλιευτικών πεδίων, δορυφορικά δεδομένα, σχέδια διαχείρισης Abstract The last years, the Vessel Monitoring System (VMS) is used to control the activities of professional fishing vessels with total length greater than 15m. The objective of this paper is to propose a method to analyze primary VMS data and to estimate the fishing effort. The method was applied in the fleet of open sea fishery (trawlers, purse seines) where monthly estimates of fishing effort by fishing category were computed. The produced high resolution cartographic maps are useful to identify the fishing grounds of Greece, to estimate the fishing pressure and to study the spatial and temporal migration of the fishing fleet. According to the results, N. Aegean is the most important fishing ground in the country, while it assembles the 32% of annual fishing effort of trawlers and 41.63% of purse seines. In the Aegean Sea the fishing effort represents the 88.3% for the trawlers and 90.2% for the purse seines, while in Ionian Sea the corresponding values are 11.7% and 9.8%. The results of the analysis of VMS data can be useful in the scientific community and the fisheries administrators, giving the possibility to make predictions and scenarios to control the fishing effort and to elaborate management plans for the sustainability of stocks.
Ecological indicators calculated from landings data have been extensively used to evaluate the effects of fishing on marine ecosystems. However, few studies have tested the possible effects of gear and spatial aggregation of landings data on different ecological indices over a long-term period. To do this, we applied the Marine Trophic Index (MTI) and Fishing in Balance (FiB) index to Greek landings data disaggregated by gear and area for the period between 1928 and 2010. Aggregated data showed an increase in MTI due to expansion of fisheries that was also confirmed in most of the disaggregated analysis conducted by fishing subareas and main gear types. On the other hand, disaggregated landings by gear and area provided additional insights: while aggregated landings showed no decline in MTI, disaggregated landings showed that 63% of cases indicated an increase in MTI while 11% showed a decline. When small pelagics and other species were excluded, these values changed to 42% and 24%, respectively. Thus, disaggregated data permitted the identification of ecologically meaningful critical situations with decreasing MTI, as has been observed in shallow enclosed gulfs in close proximity to large cities and/or for the main fishing grounds exploited for long periods by seiners (purse and beach). Moreover, disaggregating landings data by gear increased the ability of explaining observed trends, avoiding masking (averaging) effects and accounting for differential development and adaptability of different gear.
Data on fishing effort expressed in vessel days at sea and corresponding landing/day for a large number of species have been collected by the Institute of Marine Biological Resources (IMBR) since the second half of 1995. Data were collected over a grid of 21 stations throughout the Greek seas. In the present study we analyzed the monthly days at sea as well as catch per day for trawlers and purse seiners from 1996 to 2000, by general linear models and trend analysis. The following vessel size groups per gear were considered: (a) trawlers smaller and larger than 20m; (b) purse-seiners smaller and larger than 15m. collected data were also aggregated for five fishing sub-areas: the North Aegean, the Central Aegean, the South Aegean, Cretan waters and the Ionian Sea. Trend analysis of landing/day time series indicated that demersal and pelagic resources are declining in the main fishing grounds. Declining landing/day trends are regarded as indicators of overfishing, especially in the light of the fact that high catch rates are maintained by fishing in ‘hot spots’. The results of the present analysis provide, for the first time, important information on the sustainability of the fisheries in the north-eastern Mediterranean, an area characterized by a complete lack of accurate long-term data on effort and catch per effort
In the present study, Greek marine fisheries landings per gear and subarea were reconstructed for the period 1928-2007. The reconstruction was based on the landing per species, gear (i.e., trawls, purse-seines, beach-seines and other small-scale gears operated from vessels with engine power ≥19 HP) and subarea during 1990-2007 that have been recorded by the Hellenic Statisti-cal Authority but have never been published or presented before, and the landings from small-scale vessels (with engine power <19 HP) by prefecture that have been recorded by Agricultural Statistics of Greece during 1970-2007. The results showed that the reconstructed total landings time series, as well as those of each gear separately, increased substantially from 1928 up to mid 1990's and then declined for the remaining years. The same trend was almost true for the vast majority of the total (i.e. all species combined) landings and of the most abundant species per gear and subarea, depending on each case. This indicates that the general trend identified were not the result of aggregating landings over different gears and subareas but rather a general pat-tern for most gears, subareas and dominant species. Apart from studying the historical develop-ment of the Greek fisheries, the main reason for reconstructing Greek fisheries landings was to use this series for applying various ecological indices/analyses on a gear/subarea basis and to de-velop ecosystem-based models for comparing different management scenarios for Greek waters.
Illegal and unreported fishing contributes to overexploitation of fish stocks and is a hindrance to the recovery of fish populations and ecosystems. This study is the first to undertake a world-wide analysis of illegal and unreported fishing. Reviewing the situation in 54 countries and on the high seas, we estimate that lower and upper estimates of the total value of current illegal and unreported fishing losses worldwide are between 23.5 bn annually, representing between 11 and 26 million tonnes. Our data are of sufficient resolution to detect regional differences in the level and trend of illegal fishing over the last 20 years, and we can report a significant correlation between governance and the level of illegal fishing. Developing countries are most at risk from illegal fishing, with total estimated catches in West Africa being 40% higher than reported catches. Such levels of exploitation severely hamper the sustainable management of marine ecosystems. Although there have been some successes in reducing the level of illegal fishing in some areas, these developments are relatively recent and follow growing international focus on the problem. This paper provides the baseline against which successful action to curb illegal fishing can be judged.
The public perception of fisheries is that they are in crisis and have been for some time. Numerous scientific and popular
articles have pointed to the failures of fisheries management that have caused this crisis. These are widely accepted to be
overcapacity in fishing fleets, a failure to take the ecosystem effects of fishing into account, and a failure to enforce
unpalatable but necessary reductions in fishing effort on fishing fleets and communities. However, the claims of some analysts
that there is an inevitable decline in the status of fisheries is, we believe, incorrect. There have been successes in fisheries
management, and we argue that the tools for appropriate management exist. Unfortunately, they have not been implemented widely.
Our analysis suggests that management authorities need to develop legally enforceable and tested harvest strategies, coupled
with appropriate rights-based incentives to the fishing community, for the future of fisheries to be better than their past.
Illegal exploitation of resources is a cause of environmental degradation worldwide. The effectiveness of conservation initiatives such as marine protected areas relies on users' compliance with regulations. Although compliance can be motivated by social norms (e.g. peer pressure and legitimacy), some enforcement is commonly necessary. Enforcement is expensive, particularly in areas far from land, but costs can be reduced by optimizing enforcement. We present a case study of how enforcement could be optimized at Cocos Island National Park, Costa Rica, an offshore protected area and World Heritage Site. By analysing patrol records we determined the spatial and temporal distribution of illegal fishing and its relationship to patrol effort. Illegal fishing was concentrated on a seamount within the Park and peaked during the third year-quarter, probably as a result of oceanographic conditions. The lunar cycle in conjunction with the time of year significantly influenced the occurrence of incursions. The predictability of illegal fishing in space and time facilitates the optimization of patrol effort. Repeat offenders are common in the Park and we suggest that unenforced regulations and weak governance are partly to blame. We provide recommendations for efficient distribution of patrol effort in space and time, establishing adequate governance and policy, and designing marine protected areas to improve compliance. Our methods and recommendations are applicable to other protected areas and managed natural resources.
Two recent papers point to differing trends in the status of fish stocks in the Mediterranean and Atlantic fisheries of Europe. We discuss the possible reasons for these contrasting trends in relation to the history, ecosystems, fisheries and management in the two regions.
In the Mediterranean Sea, socio-economic drivers may accelerate the process of Exclusive Economic Zone (EEZ) declarations. Despite the challenges, the EEZ declarations may provide important opportunities for leveraging change to national policy towards the development of large-scale conservation of marine ecosystems and biodiversity in this zone. Using the Mediterranean Sea as a case study, we aim to highlight a set of best practices that will maximize the potential for the development of large-scale marine conservation initiatives. These include a range of approaches, such as using surrogates to fill the many biodiversity data gaps in the region, further the development of consistent and open access databases, and the utilization of technological developments to improve monitoring, research and surveillance of less accessible and under explored marine areas. The integration of Mediterranean-wide and local conservation efforts, the facilitation of transboundary collaboration, and the establishment of regional funds for conservation will further enhance opportunities for marine conservation in this region.
In recent years, fisheries management has succeeded in stabilizing and even improving the state of many global fisheries resources [1–5]. This is particularly evident in areas where stocks are exploited in compliance with scientific advice and strong institutional structures are in place [1, 5]. In Europe, the well-managed northeast (NE) Atlantic fish stocks have been recovering in response to decreasing fishing pressure over the past decade [3–6], albeit with a long way to go for a universal stock rebuild [3, 7]. Mean-while, little is known about the temporal development of the European Mediterranean stocks, whose management relies on input controls that are often poorly enforced. Here, we perform a meta-analysis of 42 European Medite-rranean stocks of nine species in 1990–2010, showing that exploitation rate has been steadily increasing, selec-tivity (proportional exploitation of juveniles) has been dete-riorating, and stocks have been shrinking. We implement species-specific simulation models to quantify changes in exploitation rate and selectivity that would maximize long-term yields and halt stock depletion. We show that stocks would be more resilient to fishing and produce higher long-term yields if harvested a few years after maturation because current selectivity is far from optimal, especially for demersal stocks. The European Common Fisheries Policy that has assisted in improving the state of NE Atlantic fish stocks in the past 10 years has failed to deliver similar results for Mediterranean stocks managed under the same policy. Limiting juvenile exploitation, advancing manage-ment plans, and strengthening compliance, control, and enforcement could promote fisheries sustainability in the Mediterranean.
1. Despite their geographic proximity, the Gulf of Ambracia and the Inner Ionian Sea Archipelago are
remarkably different in terms of environmental features, human activities, and dolphin species composition
and densities.
2. Interviews of small-scale professional fishermen (n = 100) showed that younger generations do not see any
future in fisheries and that the traditionally-oriented fishing community is rapidly changing.
3. Fish captures have reportedly decreased dramatically during the last 20 years. The main factors having an
adverse impact on the sustainability of small-scale fisheries differed significantly between areas.
4. Net damage as a consequence of dolphin predation was almost unanimously reported. Hence, fishermen
seemed genuinely interested in collaborating in future research initiatives to evaluate the damage caused by
dolphins and to explore potential mitigation strategies.
5. Dolphins were not the only animals held responsible for net damage, nor those reportedly causing the largest
economic loss to small-scale fisheries, which was attributed to either sea turtles or the critically endangered monk
seal, depending on the area.
6. The fishermen of the Gulf of Ambracia advocated the introduction of measures to curtail habitat degradation
as the top priority, while their colleagues of the Inner Ionian Sea Archipelago identified fisheries management
measures and effective law enforcement as the most urgently needed actions.
7. Given the high dependency of local communities on fisheries, ensuring their sustainability is crucial to
providing local fishers with sufficient income. The top management measures identified by local small-scale
fishermen perfectly match the priorities set out within the Natura 2000 network, achievable through an
ecosystem-based approach. Failure to take action in a timely manner may lead to irreversible environmental
damage coupled with the need for harsher regulatory measures.
Information on the abundance of demersal fishes on the shelf of Crete has been collected through a 3-year bottom trawl survey carried out at fixed sampling stations. Cluster analysis identified three major station-groups delimited by the nature of the substrate. Two of the identified substrate zones were situated on the continental shelf while the beginning of the third zone coincided with the start of the continental slope. Discriminant analysis applied to the abiotic variables defined that depth was the most important variable in discriminating between the identified groups. Discriminant analysis also identified that the most important species in discriminating among station-groups were Capros aper (Linnaeus, 1758), Gadicuh argenieus argenteus Guichenot, 1850, Merluccius merluccius (Linnaeus, 1758), Mullus surmuletus Linnaeus, 1758 and Spicara flexuosa Rafinesque, 18 10. Association analysis revealed few species pairs having significant associations which in most cases seem to be related to the reproductive migration of these species. The results demonstrate that there is a pronounced change with the substrate and by extension with depth in the ichthyofaunal composition of the shelf of Crete. It has also been suggested that there may be a particular relationship between the fish communities of the two zones of the continental shelf.
Fishing at the early stage of fisheries development most probably approximated natural predation. Nowadays, fishing approximates ''extermination'' with dramatic effects on aquatic ecosystems. Conventional fisheries models and management practices are inadequate to handle the present situation because, among many other factors, fishing: (a) drives fish stocks to exhibit smaller body sizes and age/length at maturity (i.e., ''tropicalization'') and (b) increases catch variability, thus increasing uncertainty. The realization of (a) and (b) renders conventional practices even more inadequate, thus producing a never-ending positive feedback loop. Although the application of the precautionary approach to fisheries management together with the development of indicators and reference point values that trigger management actions seem to be an important step forward, their adoption within the framework of the same conventional models used to assess fish stocks could introduce another degree of complexity into existing models. With Ockham's razor as a primary guiding principle, the advantage of using ever more complex models is suspect. Ecosystem management seems the only alternative. Within this framework, alternative simpler ''models and strategies'' such as large-scale marine protected areas, in which no fishing takes place, are available and promising, and their adoption as a primary management tool satisfies simultaneously all objectives that have been set for ecosystem management.
The development of a typology of the Greek small-scale fishermen, based on socio-economic and fisheries information was examined using data from 551 fishermen interviews in 18 prefectures of Greece. The fishermen are relatively aged, they have mostly attained elementary education and their annual income is low. The catch is traded in both the wholesale and the retail market. The income from fisheries is significantly higher in continental than insular prefectures and higher in the Aegean than the Ionian Sea. The fishermen were categorised in three groups of dependence on fisheries (high, medium and low) according to the percentage of income originating from fishing, with more than 60% of the fishermen belonging to the high dependence group. There were significant differences among these groups in the fishermen age, annual income from fisheries, vessel length and the yearly days of fishing activity. The nature of the fishing licensing system and its implications for management are discussed and also compared to other European and Mediterranean countries. The individual treatment of the identified groups in the licensing procedure is discussed with regard to its fisheries and social impact. The pronounced geographic features revealed by the study on the level of dependence on fishing suggest that the regional particularities, linked to ecosystem heterogeneity, should be considered carefully in the management process.
The fight against illegal, unreported and unregulated (IUU) fishing activities has recently become a high priority in the international fisheries management agenda. While a number of academic contributions have sought to improve the understanding of the problem, most remain limited in scope. To help policy makers obtain a more comprehensive picture of the situation, the OECD Committee for Fisheries recently completed a study addressing the full economic dimensions of IUU fishing in an integrated manner. This paper presents the analytical framework developed by the OECD as well as some of the key results of the study regarding the causes of and the potential solutions to this widespread problem.
The illegal plundering of fishing stocks worldwide is masked behind a maze of corporate structures that makes discovery of the beneficiaries of such activity, difficult, if not impossible to identify. This paper outlines the problem of illegal fishing and then develops a multi-layered response to avert the veil of corporate entity being used as a means of preventing domestic States from answering the principal thematic question—who is the true beneficiary of this illegal behaviour, and who should be held responsible.
We present a conceptual model for the analysis of the costs and benefit aspects of the risk inherent in illegal, unreported and unregulated (IUU) activity. We then develop and present a map of IUU incidences as reported in the Fisheries Centre's Sea Around Us project IUU global database. This map shows that IUU activities are quite widespread geographically. We next present an analysis of the cost and benefit aspects of risks of IUU fishing. A key result of the study is that for the cases analyzed as a group; the expected benefits from IUU fishing far exceed the expected cost of being apprehended. For an assumed 1 in 5 chance of being apprehended, our calculations show that reported fines for the vessels apprehended will have to be increased by 24 times for the expected cost to be at least as much as the expected benefits.
The current system of port state control lacks transparency, accountability, and the global reach to punish fishers who are illegally emptying our oceans.
The global extent of illegal fishing. Fisheries Ecosystems Restoration Research Fisheries Centre
- D Agnew
- J Pearce
- T Peatman
- T Pitcher
- G Pramod
D. Agnew, J. Pearce, T. Peatman, T. Pitcher, G. Pramod, The global extent of
illegal fishing. Fisheries Ecosystems Restoration Research Fisheries Centre,
University of British Colombia and Marine Resources Assessment Group,
Vancouver and London 2008.
- J H Zar
J.H. Zar, Biostatistical Analysis., 4th ed., Prentice Hall, Inc., New Jersey, USA,
1999.
718 Communication from the Commission to the European Parliament and the Council on the proposal for a Council Regulation establishing a Community control system for ensuring compliance with the rules of the Common Fisheries Policy
COM(2008) 718 Communication from the Commission to the European Parliament and the Council on the proposal for a Council Regulation establishing
a Community control system for ensuring compliance with the rules of the
Common Fisheries Policy. 〈http://eur-lex.europa.eu/legal-content/EN/TXT/
PDF/?uri ¼CELEX:52008DC0718&from¼ en〉.
laying down certain technical measures for the conservation of certain stocks of highly migratory species
EC Council Regulation No 973/2001 of 14 May 2001 laying down certain
technical measures for the conservation of certain stocks of highly migratory
species. Official Journal of the European Communities L 137/1 19 May 2001.
Why fish piracy persists: the economics of illegal, unreported and unregulated fishing
OECD, Why fish piracy persists: the economics of illegal, unreported and
unregulated fishing, Paris, 2005.
Socio-economic status of the Hellenic capture fisheries sector
- A Conides
A. Conides, Socio-economic status of the Hellenic capture fisheries sector, in:
C. Papaconstantinou, A. Zenetos, V. Vssilopoulou, G. Tserpes (Eds.), State of the
Hellenic marine fisheries, Hellenic Centre for Marine Research, Athens, Greece,
2007.
The Badminton project: D3 Report in the Badminton project Work Package 4: Socio-Economic and Institutional Incentives for discarding: Socioeconomic and Institutional Incentives influencing Fishers' behaviour in relation to fishing practices and discard, 2012. Final Report
- S Q Eliasen
- N Papadopoulou
- V Vassilopoulou
- T Catchpole
S.Q. Eliasen, N. Papadopoulou, V. Vassilopoulou, T. Catchpole, The Badminton
project: D3 Report in the Badminton project Work Package 4: Socio-Economic
and Institutional Incentives for discarding: Socioeconomic and Institutional
Incentives influencing Fishers' behaviour in relation to fishing practices and
discard, 2012. Final Report. 〈http://83.212.243.10/badminton.html〉.
establishing a Community system to prevent, deter and eliminate illegal, unreported and unregulated fishing, amending Regulations (EEC) No 2847/93
- Council Regulation
EC, Council Regulation No 1005/2008 of 29 September 2008 establishing a
Community system to prevent, deter and eliminate illegal, unreported and
unregulated fishing, amending Regulations (EEC) No 2847/93, (EC) No 1936/
2001 and (EC) No 601/2004 and repealing Regulations (EC) No 1093/94 and
(EC) No 1447/1999.