Case studies
During GAP 1, stakeholder and scientist partners will together plan case-studies for future participatory research that will combine their knowledge. Formulation of ideas, planning of case studies and a research project will be undertaken through a series of Regional and European workshops. Some examples of the GAP1 case studes are interviewed below.
Please see the "GAP 1 Case studies Progress summary April 2009"
for an overview of all successful Case studies:
http://www.gap1.eu/Results/Reports.htm
Case study FADs on Tunas of the Indian Ocean |
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Conservation and management issues related to FADs utilized by the European tropical tuna fishery - Interview with Laurent Dagorn, IRD, France
 Landing a common goal on a research question can be quite a challenge, even if the group has a long history of collaboration. In the process of defining the correct research questions the FAD/Tuna Case study group has made large efforts to overarch the gaps of knowledge and understanding between stakeholders in their group.
(Photo: FADIO/IRD-Ifremer/ M. Taquet)
The group consists of researchers from French IRD (L'Institut de recherche pour le développement) and Spanish AZTI (Fundación AZTI), ship owners and skippers of Tuna fishery vessels sailing the Indian Ocean. The ship owners are of both French and Spanish nationality and have previous experience of collaboration through the tuna commission (IOTC), since in tuna stock areas of the in Indian Ocean, Spanish and French fleet owners are usually working together. Now, after several GAP1 Regional meetings, the group is harmonized on their subject and ready to provide a scientific proposal.
Collaborative research
The first Regional meeting took place in May 2008, where the group identified general questions to be more studied. The second meeting was held in Dec 2008, main topics were then definitely defined with fleet owners, but to get more precise questions it was decided to get the point of view of skippers as well. The species concerned in the study were Skipjack tuna (Katsuwonus pelamis), Bigeye tuna (Thunnus obesus) and Yellowfin tuna (Thunnus albacares) tuna.
After the second meeting Dr Laurent Dagorn, GAP1 coordinating scientist at IRD, Seychelles was happy to report: “We're really going forward in this very interesting exercise. We agreed upon a common and restricted objective, but we need to get the points of view from some skippers to be sure we have a full coverage of all stakeholders. Then, we'll finalize specific objectives, methods, etc. in order to prepare a proposal to be ready by late March 2009.
The research questions are now finally, after several regional meetings, boiled down to addressing conservation and management issues related to fish aggregating devices (FADs). In the study fishers´ knowledge on the fishery and fishes are combined with scientific knowledge and used to achieve the objectives of the case study.
Is it possible to extract tuna from FAD fisheries in a sustainable way?
Fishing around floating objects, usually called fish aggregating devices (FADs), has become one of the main strategies used by industrial tuna purse seiners all over the world to catch tropical tuna , the alternative strategy is to catch free-swimming schools.
(Photo: FADIO/IRD-Ifremer/ M. Taquet)
More than half of the world’s tropical tuna catches are being made around FADs (Fonteneau et al. 2000). This is particularly true in the Indian Ocean, where in some years, the percentage of tuna caught from FADs has reached close to 80%.
This method of fishing has raised several concerns in both the scientific and fishing communities due to the fact that:
(1) FADs could increase the catchability of tuna, and in particular those of juvenile Yellowfin and Bigeye tuna.
(2) FADs contribute to the incidental catch of non-target species, such as sharks.
(3) Some scientists have advanced the ecological trap hypothesis stating that FADs could have negative impacts on tuna ecology (Marsac et al. 2000; Hallier & Gaertner 2008).
The aim of the Case study is to address conservation and management issues related to FADs from a new perspective: Associating scientists and stakeholders such as skippers and fleet owners, to address research and management issues. This will be related to the use of FADs by the current fleet. The aim is also to define the best FAD-fishing practices and appropriate management measures to be taken to ensure a sustainable fishery. The scientific community and the stakeholders therefore need to understand the exact consequences on tuna and non target species of (1) fishing around FADs, and (2) deploying large numbers of FADs in the ocean.
Dagorn says: “Luckily we are not working with bluefin tuna, tropical tunas don’t have in the same status.” According to him the IOTC status of the fisheries claims there are no problems with Skipjack, Bigeye and Yellowfin being at the equilibrium (but Yellowfin were overexploited from 2003 to 2006).
IOTC : “SS2 stock assessment of yellowfin tuna: trends in total yellowfin biomass, spawning biomass and recruitment over time”. IOTC report:
http://www.iotc.org/files/proceedings/2008/wptt/IOTC-2008-WPTT-R[E].pdf
Concluding direction of research
Through the series of regional meetings the case study group went from focusing on short term subjects such as Bycatch to long term ones such as what the effects of FADs on the ecology of tunas and other species are, and how juvenile catches under FADs affect population structure.
An ongoing parallel research project helps improve this knowledge; MADE project (soon to be released: www.made-project.eu. MADE will help to define the best FAD-fishing practices, following works from the European project FADIO. (www.fadio.ird.fr). However, MADE does not integrate the participation of fishermen as in the concept of GAP. An idea would be to combine MADE and GAP2 projects to provide new insights into the FAD fisheries.
The development of research questions in the group started with fishers and scientists agreeing on the following research questions:
1. Identify negative and positive effects of FADs on the ecosystems (are FADs ecological traps for tunas and other associated species?).
2. How much and how does the amount of juvenile tunas caught around FADs affect the tuna populations?
3. Can fish behavior provide indicators of the status and evolution of the ecosystems and be used to predict the changes in the ecosystems and therefore improve the stock assessments?
Dagorn says the group is not currently in contact with NGOs but regards studying the effect of FADs a good collaboration ground. “We received full support from the EU Commission. In our December 2008 meeting the secretary of IOTC, Tuna Commission was invited.” Dagorn feels there were no specific challenges of cooperation in his group, none with ship owners, neither with skippers. However, there were diverse opinions regarding the research questions. One of them was whether catching juvenile tropical tunas negatively affect the tuna populations. The other was if releasing many artificial FADs has a negative impact on the biology of individuals (“Ecological trap”- hypothesis).
 Since negative effects of FADs are not properly proved scientifically, Dagorn claims opinions might sometimes be skewed and the question really deserves investigation. He states that this group is not trying to prove positive or negative effects, but is simply taking an arbitrary point of view.
(Photo: FADIO/IRD-Ifremer/
O. Dugornay)
References
Fréon P, Dagorn L, 2000. Review of fish associative behaviour: toward a generalisation of the meeting point hypothesis. Review in Fish Biology and Fisheries, 10: 183-207.
Moreno G, Dagorn L, Sancho G, Itano D, 2007. Fish behaviour from fishers´ knowledge: the case study of tropical tuna around drifting fish aggregating devices (DFADs). Canadian Journal of Fisheries and Aquatic Sciences, 64: 1517-1528.
Dagorn L, Holland KN, Itano DG, 2007. Behavior of yellowfin (Thunnus albacares) and bigeye (T. obesus) tuna in a network of fish aggregating devices (FADs). Marine Biology, 151:595-606.
Gaertner JC, Taquet M, Dagorn L, Mérigot B, Aumeeruddy R, Sancho G, Itano D. Visual censuses around drifting fish aggregating devices (FADs): a new approach for assessing the diversity of fish in open-ocean waters. Marine Ecology Progress Series, 366: 175-186.
Girard C, Benhamou S, Dagorn L, 2004. FAD: Fish Aggregating Device or Fish Attracting Device? A new analysis of yellowfin tuna movements around floating objects. Animal Behaviour, 67:319-326.
Moreno, G., Dagorn L., Sancho, G., García, D., and Itano, D. 2007. Using Local Ecological Knowledge (LEK) to provide insight on the tuna purse seine fleets of the Indian Ocean useful for management. Aquat. Living Resour 20: 367-376
Moreno, G., Josse, E., Brehmer, P., and Nottestad, L. 2007. Echotrace classification and spatial distribution of pelagic fish aggregations around drifting fish aggregating devices (DFAD). Aquat. Living Resour 20: 343-356
Dagorn, L., Holland, K.N., Hallier, J.P., Taquet, M., Moreno, G., Sancho, G., Itano, D.G., Aumeeruddy, R., Girard, C., Million, J., and Fonteneau, A. 2006. Deep diving behavior observed in yellowfin tuna (Thunnus albacares). Aquat. Living Resour./Ressour. Vivantes Aquat. 19(1): 85-88.
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Case study - Wadden Sea Shrimp fishery, Germany |
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How can the German Crangon crangon fishery of Wadden Sea respond to climate change? Interview with Kai Wätjen, Biologist, AWI, Bremen Germany
 “Due to sea level rise and temperature increase, the unique Wadden Sea and its residents, who live from the fishing industry, are facing a great challenge.”, Kai Wätjen says.
(Fisherman Daniel Ahrens cooking shrimps on board POLARIS, Photo: K. Wätjen)
Brown shrimp or common shrimp, Crangon crangon is a common German fishery with a long tradition. In Germany the Wadden Sea fishery is a small scale fishery including around 230 vessels with about 2 or maximum 3 people in each boat. Local observations by fishermen indicate that there are impacts of climate change on the fish and decapod fauna in the Wadden area. The research of this GAP1 Case study group will investigate how climate affects the local fauna and try to suggest how the changes can be handled. Management plans currently also include the consideration of a certification of the fisheries with the MSC, Marine Stewardship Council.
Kai Wätjen is a researcher at the Alfred Wegener Institute with a small cooperative of 7 boats as stakeholder partner. He regards his case study collaboration with one of their shrimp fishers to be running smoothly. The research questions developed by the group cover global change and response on climate change.
- How does Crangon crangon react to climate change?
- How can the Crangon crangon fishery of Wadden Sea respond to climate change?
- Is there a loss of predators?
- New species are immigrating, are they invasive?
- Are there new target species appearing?
- Will the catch season for brown shrimp extend due to warmer temperatures?
LEK, Local Ecological Knowledge
Perhaps the fishermen of the Wadden Sea did observe effects of climate change: There are observations of new species such as the edible trigger fish, also since a few years an increase of the bivalve razor clam (Ensis directus) has been observed as well as goatfish species, striped mullet (Mullus barbatus) and red mullet (Mullus surmuletus) both fishes are very famous on fish markets in the Mediterranean. Relatively new are also Pacific oysters that are big and tasty but difficult to harvest. Fishers are now considering techniques to include them as new target species, in some areas the oysters even suppress the native blue mussel (Mytilus edulis). The relatively old newcomer jackknife mussel (Ensis directus) could also be of commercial interest.
For the Brown shrimp there are observations of changed migration patterns from West to NE part of the North Sea. The catches near the English Channel decreases but instead catch increase in Eastern parts. One theory on the reason behind this change of migration pattern is influence of global climate change, stocks are then dislocated from traditional grounds. There is currently no data to support the theory; there is a need for further investigation of changes in the life history and distribution of shrimps as well as the fishing behavior and effort of the shrimp fleet. There is also a need for information about the larvae drift of Crangon crangon.
 Data deficiency
The first proposed research subject of the Wadden Sea Case study group was to investigate the impact of the North Sea winter fisheries on the Wadden Sea area. However, this subject, requested from the fishermen themselves, needed support of long term data series. Fisheries statistics has a gap of information; there is only little data available on impact on stocks. Kai Wätjen thinks it is because up until now there has been no request for such detailed stock information on brown shrimp. Since there are no quotas on shrimp fisheries there are no restrictions or detailed statistics either. But during a recent catch decrease, winter fishery in the North Sea was questioned even by fishermen.
(Beam trawl, Photo: K. Wätjen)
Fishing the Wadden Sea
The Wadden Sea area is located inside the EEZ zone of Germany and operations are limited from March to November, boats are harbored at wintertime. The landings of brown shrimp are an important factor of North Sea fisheries and ranked third in landings value (Neudecker,
2006). In the winters the large trawlers that fish for brown shrimp (C. crangon) in the North Sea make out 4% of the total landings. In 2006 approximately 85 % of the European landings were of German and Dutch origin. Other countries fishing were Denmark at about 11% and the rest was fished by UK, Belgium and France.
The core area of the fishery is the Wadden Sea, an ecosystem unique in the entire world, Europe's largest wetland and with its sand and silt surfaces the largest contiguous Wadden area of the world. It is listed as a
European Marine Protected Area and nominated as a World Heritage site. The ecology of the area is unique in Europe with a tidal influence of between 2 and 3m, 2 times/day which makes it good nursery grounds for flatfish such as plaice. It has one of the highest primary production rates in the world. The governments of the Netherlands, Denmark and Germany have been working together since 1978 on the protection and conservation of the Wadden Sea. Co-operation covers management, monitoring and research, as well as political matters. The picturesque German fleet of small trawlers, many of them wooden made and ran by small family companies, also carry an important value for the tourism industry at the North Sea coast. Tourists associate the shrimp trawlers with their holidays and a healthy Wadden Sea.
(Lowtide, Photo: K. Wätjen)
To certify or not to certify
Fishermen of the Wadden Sea are considering MSC (Marine Stewardship Council) certification. Fishers are not very happy since it is a costly process in terms of certification costs and possible gear changes, not all fishermen are willing. In Kai Wätjens’ opinion there is a gap of knowledge on certification with fishers: "What does it mean?" fishers wonder. Fishers in the Netherlands have more information, their certification is planned this year. The MSC would prefer a general certification process for all fleets fishing the Wadden Sea.
The request for MSC certification comes from wholesalers, there are two active wholesalers dominating the market on shrimps; Heiploeg and Klaas Puul. Kai Wätjen believes the cost for the certification of the North Sea shrimp fleet would be quite marginal to participants when shared by the entire fleet in the Wadden Sea and the North Sea, as is the goal of certification by MSC. According to recent information from the MSC, the certification process will proceed from the year 2010 and include all fisheries in the Wadden Sea. There are different management plans for the certification of the Dutch and the German shrimp fishery fleet. The German fishers will not accept the Dutch management plan but instead develop their own plan for certification. Their concerns regard the following:
1. Minimum price for shrimps to be fixed with the wholesalers
2. Reduce of discard and bycatch. How much discard is acceptable? A closing of the catch areas is under discussion, if bycatch or discard exceeds a certain amount, there is a need to define the amount.
3. Careful handling of discard.
 Kai Wätjen says: “A drawback when connecting certification and fisheries with issues of climate change may be that fisheries are not certified with a complete LCA (Life Cycle Analysis) of the products. The MSC are currently only certifying the fishery.”
Links/References
Bender S.& Döring, R., 2005, Fisheries economics research in Germany – Results from an EU Concerted Action for the German, fishing fleet, Inf. Fischereiforsch. 52, 2005, 36–42
Lotze, H.K., 2007, Rise and fall of fishing and marine resource use in the Wadden Sea, southern North Sea, Fisheries Research 87 (2007) 208–218
Maynou, F.& Sarda`, F., 2001, Influence of environmental factors on commercial trawl catches of Nephrops norvegicus (L.). ICES Journal of Marine Science, 58: 1318–1325. 2001
Neudecker, T. & Damm, U., 2006, 2005: record landings of brown shrimp (Crangon crangon L.) in Europe, Information Fischereiforschung 53, p 80-81
Neudecker, T. et al., 2006, Catch, landings, discard and stock of brown shrimp (Crangon crangon L.), Information Fischereiforschung 53, p 82-85 |
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Case Study Devon crabs, UK |
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Sustainable Crab fisheries in Devon? Interview with Professor Paul Hart, University of Leicester
“We have a different partnership from others in GAP1. In our group we have the comfort of 10 years experience in working together.” Professor Paul Hart is confident and has already hired a person for 6 months to collect preliminary data on spatial distribution of catches of crabs in Devon, UK. The recording of data will take place on fishing vessels gathering information on the catches to show who is catching what and where are they catching it? |
“We are using GAP1 as launching platform for further studies.” Professor Hart explains. Further money for extension of the study would give data required by methods to managing stocks sustainably. The funding body applied to is the UK Sea Fish Industry Authority. If granted it would fund a 3 year project. The planned research project would focus on how estimation of sustainable stocks can be made using data that fishermen themselves collect. The aim is to produce a different way of doing fisheries management, providing methods for fishermen to handle their own stock assessment.
ITQs are usually imposed by outside bodies.
This is innovative Small Scale Fisheries (SSF) management in a nutshell: "If fishermen can develop a sense of ownership of the exploited stock it gives them a bigger incentive to fish more sustainably" thinks Professor Hart. The resentment fishermen have of scientists comes from the notion that scientists should serve fishermen rather than act on behalf of governments. There have been similar approaches to management elsewhere; for example black cod fishermen in Canada have assisted scientists to gather data that is then used for assessments. It will be valuable to explore further this methodology within the EU management system. One possibility for control could be by auditing and certification. The cost of certification creates a drawback; it makes it prohibitive for the fisher to have to demonstrate sustainability. There is a need for a stronger case to be made for certification.
Professor Hart will use a simple model of the exploited crab biomass to direct the gathering of data that will lead to stock evaluation. Fishermen will be able to assess the long-term sustainability of the stock using methods developed by fishery science but gathering the required data themselves. 
Ultimately the fishermen would drive the management system, motivated by the possibility of increasing stock and product values.
The researchers are building a simple biomass input-output model including immigration and emigration of adult crabs, the arrival rate of their larvae, and the weight of crabs caught. The function of the model is to allow fishers to assess the sustainable biomass available for harvesting. The biomass of the catch should advisably be less than net immigration to support a continuous supply of crabs from the fishing area. This is a time - dependent model. The model will be used to simulate biomass variation in stocks to find the optimal fishing rate. The critical point of the model’s accuracy in making a prognosis for fishing pressure is the supporting data. CEFAS are currently collecting data by tagging crabs in the English Channel and this will supply rates of migration to the model. More data will be collected during the proposed project.
If funded, the data-gathering project will start in April-May 2009 and go on until March 2010. An analysis of the data will then be carried out to determine if more data is required. If stocks are sustained by migration, then an expectation is that catches on the edges of the fishing area will be high, but with variation over time and crab sex.
Paul Hart also mentioned an experiment that will have to be done, to determine the survival rate of the crabs that are thrown back as being either too small or having shells that are soft.
Early discussions with the fishers reviewed topics where crab fishers would be interested in learning more:
1. Movements and migrations: e.g. why do crabs move into deeper water during the winter – is it due to deteriorating weather conditions, or because the temperature drops?
2. Size at first reproduction
3. Reproductive characteristics: e.g. how many male crabs mate with the same female?
Other questions interesting but not critical to evaluating the stocks:
• Interference between crab and whelk fisheries
• Lobsters are considered non-migratory, however fishermen report evidence of migration, so this needs further investigation
• Aspects of spider crab biology
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