Abundances indices and biological traits of juvenile salmon sampled in the Oir river (France)

Latest version published by Institut National de la Recherche Agronomique (INRA) on Sep 25, 2019 Institut National de la Recherche Agronomique (INRA)

Since 1993, an annual campaign is conducted to quantify the abundance of juvenile Atlantic salmon in the Oir basin. It is usually done in September and according to the protocol of Prévost and Baglinière (1995). The electric fishing protocol of Prévost and Baglinière (1995) is used, which is specific to Atlantic salmon young of the year (0+ parr) . Sampling is restrited to areas with shallow running water flowing on coarse bottom substrate i.e. the preferred habitat of young of the year salmon.This data set consists of the abundance and biological traits measured on the fish sampled on this occasion. Observations made on this occasion are descriptive data (species, sex, maturation and biometric (length, weight). In addition, scales samples are taken to determine the age of the fish.

Data Records

The data in this occurrence resource has been published as a Darwin Core Archive (DwC-A), which is a standardized format for sharing biodiversity data as a set of one or more data tables. The core data table contains 8,119 records. 1 extension data tables also exist. An extension record supplies extra information about a core record. The number of records in each extension data table is illustrated below.

  • Occurrence (core)
  • MeasurementOrFact 

This IPT archives the data and thus serves as the data repository. The data and resource metadata are available for download in the downloads section. The versions table lists other versions of the resource that have been made publicly available and allows tracking changes made to the resource over time.


Download the latest version of this resource data as a Darwin Core Archive (DwC-A) or the resource metadata as EML or RTF:

Data as a DwC-A file download 8,119 records in French (343 KB) - Update frequency: unknown
Metadata as an EML file download in English (19 KB)
Metadata as an RTF file download in English (18 KB)


The table below shows only published versions of the resource that are publicly accessible.

How to cite

Researchers should cite this work as follows:

Marchand F., Azam D., Delanoë R., Destouches J-P; Tremblay J. and Prévost E. 2017. Abundances and biological traits of the juveniles salmon sampled in the survey of Salmon abundance Indices in the Oir river (France).


Researchers should respect the following rights statement:

The publisher and rights holder of this work is Institut National de la Recherche Agronomique (INRA). This work is licensed under a Creative Commons Attribution (CC-BY) 4.0 License.

GBIF Registration

This resource has been registered with GBIF, and assigned the following GBIF UUID: 5ea28eaa-7e0c-417c-b525-9c737d18823f.  Institut National de la Recherche Agronomique (INRA) publishes this resource, and is itself registered in GBIF as a data publisher endorsed by GBIF France.


Occurrence; Population density; population distribution; catch effort; salmo salar; salmon


Who created the resource:

Frédéric Marchand
INRA-U3E 65 rue de St Brieuc, CS 84215 35042 Rennes FR +33 223485786
Didier Azam
INRA-U3E 65 rue de St Brieuc, CS 84215 35042 Rennes FR +33223485786
Richard Delanoë
ONEMA-DAST Le moulin de Cerisel 50220 Ducey 0688155198
Jean-Pierre Destouches
INRA-U3E 65 rue de St Brieuc, CS 84215 35042 Rennes +33 223485786
Julien Tremblay
INRA-U3E 65 rue de St Brieuc, CS 84215 35042 Rennes +33 223485786
Etienne Prévost
INRA-ECOBIOP Aquapôle - Ibarron 64310 St-Pée-sur-Nivelle FR +33559515983

Who can answer questions about the resource:

Didier Azam
INRA-U3E 65 rue de St Brieuc, CS 84215 35042 Rennes FR +33 223485786

Who filled in the metadata:

Frédéric Marchand
INRA-U3E 65 rue de St Brieuc, CS 84215 35042 Rennes FR +33 223485786

Who else was associated with the resource:

Nadine Herrard
INRA-U3E 65 rue de St Brieuc, CS 84215 35042 Rennes FR +33 223485786
GBIF France
IT support
GBIF France 43 rue Buffon 75005 Paris 0033140798065

Geographic Coverage

The Oir river in Normandy (France). http://services.sandre.eaufrance.fr/Courdo/Fiche/client/fiche_courdo.php?CdSandre=I9280600

Bounding Coordinates South West [48.6, -1.29], North East [48.68, -1.1]

Taxonomic Coverage

No Description available

Species  Salmo salar (Saumon atlantique, Atlantic Salmon)

Temporal Coverage

Start Date / End Date 1993-10-15 / 2017-09-19

Project Data

The Research Observatory on Diadromous Fish in Coastal Streams (ORE DiaPFC) is a research infrastructure steered by INRA in partnership with AFB and part of the AFB-INRA R&D center. It's focused on the study of the evolution of diadromous fish populations under the influence human induced environmental changes that affect these rivers (mainly climate and effects of agriculture). Diadromous species of primary interest are salmon (Salmo salar), trout (Salmo trutta), eel (Anguilla Anguilla), shads (Alosa sp.), and lampreys (Lampetra sp. and Petromyzon marinus). These species are threatened by the consequences of human activities. They are flagship species for the biodiversity of coastal streams. Nowadays, these streams are the main refuges for diadromous fish that have disappeared or dramatically declined on larger rivers. This ERO DiaPFC is a Research Infrastructure based on four coastal streams of the Atlantic and Channel coast of France: the Bresle and the Oir in Normandy, the Scorff in Brittany and the Nivelle in the Pays Basque. These four rivers are equipped with diadromous fish trapping facilities and are thoroughly and continuously surveyed from the mid 1980s. They are twinned with experimental ecology facilities located in Rennes (Brittany) and Saint-Pée-sur-Nivelle (Pays Basque). This set of facilities is complemented by individual-based eco-genetic simulators for in silico experimentation on virtual populations.

Title Observatoire de Recherche en Environnement des poissons diadromes sur les Fleuves Côtiers - Ecological Research Observatory on Diadromous Fish in coastal streams
Funding - INRA : French National Institute for Agricultural Research - AFB : French Agency for Biodiversity - FEAMP : (European Fund for Maritime Affairs and Fisheries). Since 2017, data collected on salmon in the framework of the ORE DiaPFC have been included in the national program for the data collect in support of scientific advice for the Common Fisheries Policy (DCF - Work Plan for data collection in the fisheries and aquaculture sectors 2017-2019) for the European regulations on fisheries management. In this context, INRA and AFB contribute to the National Work Program piloted by the DPMA of the Ministry of the Environment. This program is financially supported by FEAMP
Study Area Description This infrastructure Research relies on three coastal streams of the Atlantic facade Channel, the Bresle and Oir in Normandy (Manche), the Scorff in Brittany (Morbihan) and the Nivelle in the Basque Country (Pyrenees Atlantiques).
Design Description The issue of 'Research Observatory on Diadromes Fish in Coastal Rivers (ORE DiaPFC) is to study the evolution of diadromous fish populations as a result of environmental changes (climate change and changes related to agriculture ) that affect these rivers.

The personnel involved in the project:

Point Of Contact
Etienne Prévost

Sampling Methods

Sampling is conducted at 10 sites spread over the mainstem and over the 2 main tributaries in the area of the Oir hydrographic network colonized by Atlantic salmon. Since 2016, 1 site is sampled over the network colonized by Atlantic salmon to vérify this limit. The sites are the same every year and are visited once a year in the beginning of autumn (September).

Study Extent Oir river, CdSandre=I9280600 Latitude between 48.6840 and 48.5985; longitude between -1.2949 and -1. 0994 Source latitude and longitude : 48.6667 -1.1138 Last confluence point latitude and longitude : 48.6305 -1.2943 Oir river is located in the south of the Manche department, the Oir is a tributary of the Sélune, small Normandy coastal river flowing into the Bay of Mont Saint-Michel. The course of the Oir, long 21 km, east west, has an average gradient of 11 ‰. Its watershed of 87 km², dominated by sedimentary schist land and corneal including some granitic enclaves. The water is near neutral and reasonable quality but with high nitrate levels. On this basin, human activities are mainly from agriculture (meadows, fodder crops, dairy cattle). The upstream Sélune is not accessible to migratory fish. They are blocked to fifteen kilometers from the sea by a dam. Oir river, with its 12 Km accessible to migratory fish spawning tributary is the most productive of the network

Method step description:

  1. Juveniles salmon are caught by electric fishing. A 400 Hz pulsed current generator (Martin Pêcheur of DREAM Electronique) is used and it is proceeded as follows: 1 Two large dip-nets with metal frames are placed facing the current, lying on the bottom, and kept at a fixed position. 2 The anode scans an area of about 4-5 m upstream of the dipnet in the vein of water filtered by them. 3 Fish attracted by the anode and shocked go down into the nets guided by the electrode and driven by the water flow. 4 If necessary, the fish stuck on the bottom or in aquatic vegetation are recovered by a small hand net. 5 - Individuals are transferred into a bucket previously filled with water. The whole team moves laterally several meters (the carrier of the martin fisherman taking care not to step on the area he will next explore with the anode) out of the area that has just been disturbed by the electric field, then steps 1-5 are repeated. When one bank is reached, the progression is a few meters upstream. 5 The sampling at a given site stops after 5 minutes of actual fishing time - ie during which the electric field is applied in the water - measured directly on the counter of the electric fishing equipment. Juvenile abundance is quantified by the number of 0+ captured for a unit effort (5 minutes of fishing under the conditions specified above).
  2. Age is verified from scale reading according to standard methods described by Baglinière and Le Louarn (1987) and Richard and Baglinière (1990).

Collection Data

Collection Name Banque de données d'échantillons ichtyologiques (BDEI)
Collection Identifier
Specimen preservation methods Dried,  No treatment,  Other
Curatorial Units Between 1,600 and 1,650 Scales ,  Between 310 and 317 Fins

Bibliographic Citations

  1. Prévost E., Baglinière J.-L., 1995. Présentation et premiers éléments de mise au point d'une méthode simple d'évaluation du recrutement en juvéniles de saumon atlantique (Salmo salar) de l'année en eau courante, p. 39-48. In Gascuel D., Durand J.L., Fonteneau A., (Eds.) Les recherches françaises en évaluation quantitative et modélisation des ressources et des systèmes halieutiques. Colloques et séminaires, ORSTOM éditions, Paris.
  2. Prévost E., Nihouarn A., 1999. Relation entre indicateur d'abondance de type CPUE et estimation de densité par enlèvements successifs pour les juvéniles de saumon atlantique (Salmo salar L.) de l'année. Bull. Fr. Pêche Piscic., 352 : 19-30.
  3. Baglinière, J. L., and Le Louarn, H. 1987. Caractéristiques scalimétriques des principales espèces de poissons d’eau douce de France. Bulletin Français de la Pêche et de la Pisciculture: 1–39.
  4. Richard, A., and Bagliniere, J. L. 1990. Description et interprétation des écailles de truites de mer (Salmo trutta L.) de deux rivières de Basse-Normandie : l’Orne et la Touques. Bulletin Français de la Pêche et de la Pisciculture: 239–257.
  5. Marchand, F. et al (2017). Abundance indices and biological traits of juvenile salmon (Salmo salar) sampled in three rivers on the Atlantic and Channel coasts (France). Biodiversity Data Journal 5, e15125.

Additional Metadata

This data set is intended to be updated annually

Alternative Identifiers 5ea28eaa-7e0c-417c-b525-9c737d18823f