DemerstEm, DEMERsal ecosySTEMs

Our project is part of the PESCAO program, and aims to improve scientific advice production on shared demersal stock in West Africa (Ecowas Area) .

News on EU DEMERSTEM Project Second year (2020-2021)



The EU DEMERSTEM project started in March 2019. We are now heading towards our third year of the project whilst undergoing the turbulence of the COVID 19 Pandemic. Despite the pandemic, we are moving forward even if at a slower pace. This newsletter will remind partners that we are doing our best in spite of the situation.

February 2020: The Working group number 3 was held in Grand Bassam (17th to the 21th of February 2020). During this meeting, we started to share common methodology. We also defined templates to share data, especially commercial data (artisanal and industrial fisheries). We also agreed on common tools as the well-known R software (common tool used for stock assessment). Some sessions of this working group were dedicated to capacity building as for all DEMERSTEM WG.

Working group 3 report: Here

During March 2020- February 2021 period: : One of the activities of the work package 1 of DEMERSTEM (dedicated to the stock assessment process) aims to improve stock definition. To do that we will use several methods:

In order to feed these methods, we collect information for more than one year. Data is being collected using mainly commercial landings (artisanal and industrial one). More precisely, each of the partners has to measure, weigh, take a picture, determine sex, check for parasite presence and extract muscle tissue for genetic analysis … following an agreed protocol (establish during DEMERSTEM working group 2, update during WG 3) on more than one thousand fish. Then data is centralized on a common platform using either an Android phone app or classical excel files. Agrocampus Ouest was in charge of this data centralization. Nowadays, information about more than 18 000 fish from 6 species are available in this common database. More than 3 300 pictures are also available for morphometry analysis.

For this activity, we also had the chance to collaborate with our Gambian colleagues through agreement with CRODT. This collaboration should go forward during stock assessment working groups.

GPS monitoring of artisanal fisheries (WP3) : we have been collecting data from GPS loggers embedded on artisanal fisheries boats in Guinea and Guinee Bissao for one year in order to better estimate spatialized fishing efforts using this new technology. GPS loggers were on board until September 2020 in Guinee Bissao. However, CNSHB is still collecting data in Guinea as they include GPS monitoring as a regular data collection. One mission is planned for Mohamed Soumah in Agrocampus Ouest (IRD fundings) in 2021 in order to analyse this data. Collaboration with Nicolas Bez (IRD) and Marie-Pierre Etienne (Agrocampus Ouest) will help us to use trajectometry tools to analyse the available database. The objective of this activity is to check how this high frequency data about fishing activity could be included as complementary data within regular data collection systems.

Trophic interaction (WP4) : During 2019, Priscilla Licandro (SZN), in collaboration with IMROP and CNSHB included plankton and jellyfish data collection within national scientific surveys. These samples will be analysed by Priscilla at SZN in order to complete trophic analysis on both ecosystems.





Working group n°4 (WP1): Main activity of DEMERSTEM is to improve the scientific advice process on demersal stocks. We are currently making an inventory of available stock assessment methods and we will analyse them to find the most suitable one regarding the West African context and the transferability of these methods to CECAF and also to the scientists who will be in charge of these stocks.

A first working group on these methods was held during the first week of February. It was an online meeting due to the pandemic. Delta GLM and Global equilibrium models were presented during training courses and practical exercises.

The working group report is available Here

Long training periods: We initially planned to welcome 5 scientists in European universities for long capacity building sessions. Two of them have stopped the collaboration with DEMERSTEM. However, Jeremias Francisco - CIPA, Quenum Crespin Luc (CRO) and Yeslem El Valy (IMROP) are still involved in this activity and we are waiting for an improvement in the Covid situation to be able to support them for their second session in Europe.

DEMERSTEM newsletter 2019-2020



The UE DEMERSTEM project started officially in March 2019. At the beginning of this new year it sounds good to produce an update on past and ongoing activities.

March 2019 :

During this first year, we have met together in March during the kick of meeting in Saly (Senegal). During this meeting, we have detailed planned activities within our project. We have shared this overview with regional fisheries commissions (SRFC and FCWC) and regional institutions (ECOWAS and UEMOA). We also met representatives of other selected project under the PESCAO Call of tender: GREPPAO leaded by Pierre Failler from the University of Portsmouth and FAO colleagues.



April 2019 :

Within the Work package 3 of DEMERSTEM, a small-scale fisheries monitoring system using GPS was implemented in Guinea and Bissau Guinea. . 20 GPS have been deployed on Canoe landing in Kamsar and Katcheck port in Guinea and Cacine in Bissau Guinea. A data collection protocol was also implemented to collect landings data on GPS monitored pirogues. Mohamed Soumah, from CNSHB, has leaded this activity with trainings in both countries (for CNSHB and CIPA colleagues in charge of the survey). Mohamed carried out a second mission in Bissau to control and adapt the protocol. In April, Jérôme Guitton was in Ghana for the FAO/PESCAO kick off meeting to present DEMESTEM acivities and to try promoting synergies between DEMERSTEM and FAO project. (Ghana 24-27th April 2019)



June 2019 :

Modou Thiaw carried out a mission to Guinea in order to learn about GPS data collection implemented by Mohamed Soumah. CRODT wanted to implement a similar protocol for Kayar smal scales fisheries. Mohamed carried a mission in France (22th of June to 6th of July) to work mainly with Jerome Guitton to develop a suitable database for GPS and survey data collection. We also worked with Marie Pierre Etienne (Agrocampus Ouest) and Nicolas Bez (IRD) on data analysis. GPS trajectories are analysed to calculate and spatialized effort of pirogues. Following this mission an onboard fishing activities monitoring was carried out in order to feed learnings algorithms.
Within the work package 4 on Ecosystem Approach, and during regular scientific trawl survey, CNSHB carried out a specific jellyfish and plankton survey.



August 2019 :

For the stock identification activity (WP1) a working group was organized to share, train and promote a biological data collection (From 27th to 30th of August - Nouakchott) . This workshop was leaded by our IEO partners (Thanks to Eva Garcia Isarch and José F. Gonzalez Jiménez) and co-organized with IMROP (Thanks to Beyah). This meeting was the starting point for the biological data collection that will be carried out during one year. The main objective is to collect data for a better spatial definition of stocks selected within the DEMERSTEM project.



Septembre 2019 :

We initially planned 4 scientists for the long training period in Europe within the DEMERSTEM framework. Finally, 5 Phd candidates were selected and were invited to come to France. They arrived in September for a 3.5-month period. They shared their time between courses of the Fisheries and Aquaculture Master of Agrocampus and the main core of their case study subject. One main objective of these periods is to create synergies between DEMERSTEM partners and interaction with their AGrocampus Co-supervisor (Didier Gascuel for stock assessment case studies and Olivier Le Pape for sensitive habitat subjects). Ato Ekuban from Ghana (Fisheries division) has also been with us for two months, mainly to learn French but also to interact with Ivory Coast scientist on the sensitive habitats assessment of Ghana/Ivory Coast Area.



November 2019 :

Priscilla Licandro from SZN was on board of the Mauritanian Scientific Vessel (El Awam). Her objective was to implement jellyfish and plankton data collection within the Ecosystem work package (WP4).




Stock assessment and scientific advice (WP1)

Eva García Isarch
Responsable WP1
Meisse Beyah
Responsable WP1
Hamoud El Vadhal

Moustapha Bouzouma
Directeur adjoint de l'IMROP
Didier Gascuel
Enseignant Chercheur


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Jérôme Guitton
Coordinateur, Informaticien


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Ato Ekuban
Chercheur
Joanny Tape
Chercheur
Didier Jouffre
Chercheur

Mohamed Soumah
Informaticien
Kamarel BA

Ndiaga Thiam

Ibrahima Diallo
Chercheur
Iça Barry
Directeur du CIPA
Modou Thiaw
Chercheur
Montse Pérez
Chercheur
Jeremias Francisco
Intchama


Ibrahima Diack

Toumany Koulibaly

Improving data availability

During DemerstEm project, we plan to set up a Regional Database of Scientific trawling survey. We have been inspired by the PRESH project developped by UEMOA. Data availability is often an issue for producing a shared input for stocks assessment models. This regional Database, and the tools we can develop to easily access and use it, will improve the use of these costly data in the scientific advice process. Depending on the data policy, we will be able to plug the database to the stock assessment models.

We propose to encourage this data gathering developping ad on services as :

  • Long terme backup of the data
  • Taxonomy check tools
  • Data mining and dissemination tools
  • Easy extraction of environemental data corresponding to the scientific survey period (SST, Chl…)

On a methodologic point of view, we also plan to work on inter-calibration between data issued from different boats and protocols. We want to use trans-national survey (as Nansen scientific campaign) to calibrate national survey.

Stocks identification

We will focus on Stock identity of Case study selected species. We will use complementary approach and methodologies  :

  • 1. Genetic analysis of 2 species. DemerstEm will study population dynamics and genetics to identify spatial limits of stocks using microsatellite markers. In order to do that, selected species will have to be already described in international genetics database (as the BOLD database of the life project). Stock identity will be realised using DNS profile. Markers will be choising regarding the selected species. However, for all the species, an extract of the Cytochrome Oxydase will be analysed to feed up the open BOLD database.
  • 2. Morphometric analysis of selected species will be done and, sometimes, otolithes analysis will be done as well on some particular species.
  • 3. Life history traits analysis (growth, mortality, recruitment, breeding and spatial distribution) will be also carried out on all the selected species. The stock concept is based on a hard link between recrutment and breeders. It is so essential to set up regular based monitoring on life history trait.

Stock assessment

Once the data are collected and the stock identity defined, we can start the stock assessment process.

Several methods will be applied regarding the availability of data. We first plan to generalized methods used by Meissa et al 2017.

Then, partners will evaluate alternatives of complementary apprpriate methods to the life history traits of the species (ie : ad hoc methods for short living species) or to the data limited status of the stocks


Sensitive Habitat assessement (WP2)

Oliver Le Pape
Enseignant Chercheur
Coordinateur WP2


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Joanny Tape
Chercheur
Josepha Pinto
Chercheuse

Quenum Crespin Luc
Chercheur

Yesslem El Valy
Chercheur

The renewal of exploited marines ressources is a result of a good level of spawning biomass but also a result of the quality of habitats from wich stocks are highly dependent during part of their life cycle. Population dynamic of marine living species is very specific comparing to terrestrial species as it's a mix bettween high variabliity of fecondity, survival and high dependency to environnmental conditions. High survival variability makes this ressources highly dependent of the quality of succesives habitats used during their life cycle. In particular, renewal of fish stocks is highly dependant of nurseries habitat, located in coastal area for a large proportion of exploited ressources. During breeding season, adults concentration on spawing ground is high. However these spawing grounds is not especially located in coastal area.

Indeed, fisheries management does not have to only focus on fishing effort and catches control but should also take care of sensitives areas. Coastal area degradation due to fisheries but also due to other human activities can explain decrease of fish biomass. Sensitive area reduction or decrease of their quality can affect recruitment and fish population size. However our needed knowledge to 1) identify sensitive area necessary to renewal fish population 2) to quantify benefit of area protection against human activities is really yet poor, especially in west african countries. It is why the main objective of this wp is to collect data and available information that can help us to identify nurseries or spawing grounds and to use these data as input of models to produce quantitatives maps of sensitive habitats.

List of planned actions  :

  • Inventory and gathering from available data on coastal scientific survey or other available information on coastal distribution of juveniles and on spawing biomass distribution.
  • Inventory and collection of grounds description maps that will be consider as input of statistical models to predict juvenile distribution.
  • Quantitative models, inputs of the models are the two previously decsrcribed source of information/
  • Quantitative maps of sensitive habitats for selected species
  • A working group will be organized to discuss about resultats and methods used to produce maps.

High frequency fisheries monitoring (WP3)

Nicolas Bez
Chercheur
Coordinateur WP3
Mohamed Soumah
Informaticien
Jérôme Guitton
Coordinateur, Informaticien


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Iça Barry
Directeur du CIPA
Modou Thiaw
Chercheur

One issue in the stock assessment process is often to obtain data on small scale fisheries, especially in coastal area. This is a challenge for us to help data collection on fisheries that rely to the sensistive habitat defined in WP2. We suggest to use GPS logger ant pathway analysis to obtain more precise view of effort due to small scale fisheries in sensisitive habitat.
If data are available we could make a similiar analysis using VMS data for industrial fisheries and maybe for spawing area .


Ecosystem approach for fisheries (WP4)

Priscilla Licandro
Responsable WP4
Chercheur

Modou Thiaw
Responsable WP4
Chercheur

Didier Jouffre
Responsable WP4
Chercheur

Ibrahima Diallo
Chercheur

DemerstEm project aims to improve monospecific assessment, howerever, fisheries scientists are aware of this approach limitations. Taking into account the global ecosystem, with trophic interactions is needed;

That will be done studying trophic interactions between groups of prey and predators as a description of the Ecosystem..

Moreover Global change is also impacting west african marine ecosystem with some modification in the trophic chain.These altered trophic interaction will modify stocks productivity. Recent changes seems to be good for jellyfish profileration that will impact negativly demersal species as they are predators for fish eggs and larvaes and competitors for juveniles food.

We suggets 4 approachs to take into account the complexity of the Demersal Ecosystem to improve our knowledge on impact due to coastal Ecosystems changes on the variability of exploited stock biomass.

  • 1- Case study approach for low trophic levels (Phyto and zoo plankton)
  • 2- Case study approach for impact of jellyfish proliferation on other Ecosystem groups
  • 3- Ecopath with Ecosim modelling
  • 4- Indicators view of the Ecosystem


Who we are ?

DemerstEm project is a collaborative project between 10 research and educationnal institutions which aims to improve scientific knowledge on shared demersal stocks.

Agrocampus Ouest
Coordinateur Demerstem

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Centre National
des Sciences Halieutiques de
Boussoura

Coordinateur Demerstem

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Institut de Recherche
pour le Developpement

Institut Mauritanien
de Recherche Océanographiques
et des Pêches

Institut Espagnol
d'Océanographie

Centre de Recherche
Océanographiques de
Dakar Thiaroye

Station Zoologique
Anton Dohrn
de Naples



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Centre de Recherche
Appliquées sur les Pêches

Centre de Recherche
Océanologiques



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Commission
des pêches du Ghana

More than 30 scientists of these instututions are involved in DemerstEm

Eva García Isarch
Meisse Beyah
Hamoud El Vadhal
Moustapha Bouzouma
Didier Gascuel


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Jérôme Guitton


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Ato Ekuban
Joanny Tape
Didier Jouffre
Mohamed Soumah
Kamarel BA
Ndiaga Thiam
Ibrahima Diallo
Iça Barry
Modou Thiaw
Montse Pérez
Jeremias Francisco
Intchama

Ibrahima Diack
Toumany Koulibaly
Oliver Le Pape


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Josepha Pinto
Quenum Crespin Luc
Yesslem El Valy
Nicolas Bez
Priscilla Licandro
Catherine Le Penven
Mohamed Mayif
Abena Serwah
ASANTE

Diégane Ndong
Aboubacar Sidibe
Théa Sandberg
Betty Ndiaye NIANG
Ndèye Diouf DRAME


Documents (Click here to list files )

Working groups

Mant Thanks to Pierre-Yves Hernvann to have imagine and create the DEMERSTEM logo.


Communication tools

WG 1 : Kick Off meeting Dakar March 2019

Monitoring artisanal fisheries Working group

WG 2 : Biological date collection protocol (Nouakchott, du 27 au 30 aout 2019)

WG 3 : Data sharing and databases (Abidjan February 2020)

WG 4 : Stock assessement virtual meeting (February 2021)

WG 5 : Stock assessement meeting Dakar (November 2021)

WG 6 : stock assessement meeting Tema (Ghana) (March 2022)

WG 7 : stock assessement meeting Tenerife (Spain) (June 2022)

Abundance indices reports



This project has received funding from the European Union