DOI: 10.5281/zenodo.8009822
title: Electrofishing data for eel in the Iberian Peninsula (SUDOANG project)

description: 1. SUDOANG PROJECT
The SUDOANG project has provided common tools to managers to support eel conservation in the SUDOE area (Spain, France and Portugal). One of the goals of the project was to develop an eel abundance and distribution atlas in the three countries, based on the results of the implementation of Eel Density Analysis (EDA). This model extrapolates eel abundance from a range of river segments sampled by electrofishing, to the whole river and lake network, by considering how eel abundance, size and sex vary according to different parameters related to eel habitat.
2. SUDOANG DATABASE
Electrofishing data for Spain and Portugal were imported in the SUDOANG database (deliverable 1.2.1), whose structure is inherited from the DataBase for EEl (DBEEL), developed during a European research project (POSE - Pilot projects to estimate potential and actual escapement of silver eel, Walker et al., 2011). This database is designed to contain all data relative to eel biology and anthropogenic pressures applying to eel. During the course of SUDOANG, this database was used and ameliorated. 
The data providers (mainly SUDOE water managers, SUDOANG researchers and pilot basins from GT6: Task Group on eel stock monitoring transnational network) are listed below:

SPAIN

Ministry for ecological transition and the demographic challenge (MITECO)
Spanish Fsih Chart (SIBIC): Data from different sources (indicated in the data)
Basque Water Agency (URA) - Basque Country
Gipuzkoa Council - Gipuzkoa (Basque Country)
Navarra Council (GAN-NIK) - Navarra
Asturias Council (DGPM) - Asturias
Xunta de Galicia, Consellería de Medio Ambiente, Territorio e Vivenda - Galicia
University of Córdoba (UCO) - Andalucía
Valencian Regional Hunting and Fishing Service (GVA) - Valencia
Catalan Water Agency (ACA) - Catalonia: ACUERDO GOV/139/2013, de 15 de octubre, por el que se aprueba el Programa de seguimiento y control del Distrito de cuenca fluvial de Catalunya para el período 2013-2018
PORTUGAL

University of Porto (UP), CIIMAR
University of Lisbon, MARE: Data from different sources (indicated in the data)
3. DATA DESCRIPTION
Electrofishing data is mainly based on fishing stations, operations and eel biometry.
The station level corresponds to a location, identified by coordinates (Spatial Reference System 4326). The attributes associated with stations are:

op_id: identifier [data type: UUID]
institution: data provider [data type: character]
ref_article: reference to the article from which the data originated (only for SIBIC data source) [data type: character]
articletitle: reference linked with data (only for SIBIC data source) [data type: character]
op_placename: station name [data type: character]
x_espg_4326: longitude (EPSG: 4326) [data type: numeric]
y_espg_4326: latitude (EPSG: 4326) [data type: numeric]
country: country [data type: character]
The operation level corresponds to an event occurring at a specific date. At this level, a few more details such as the method or the material used, the wetted area, and electrofished length and width are added. The total number of eels, the numbers collected at each pass, and the number of measured eels are also included. The type of sampling used could not be specified but it is mostly single or several pass surveys. Therefore, the type was set to an unknown type of fishing. All electrofishing reporting eels in the second pass were considered as full electrofishing. The attributes associated with operation are:

id: identifier [data type: UUID]
op_id: station identifier [data type: UUID]
op_gis_layername: data provider [data type: character]
data_provider: data provider [data type: character]
op_placename: station name [data type: character]
ob_id: observation identifier [data type: UUID]
ob_starting_date: period starting date
ef_wetted_area: wetted area of the station, in m2 [data type: numeric]
ef_nbpas: the number of electrofishing pass during the observation [data type: numeric]
ef_fished_length: the electrofished river length, in m [data type: numeric]
ef_fished_width: the electrofished river width, in m [data type: numeric]
ob_origin: origin of the observation, raw data [data type: character]
ob_type: type of observation, electro-fishing [data type: character]
ob_period: time step used for observation period, daily [data type: character]
ef_fishingmethod: type of method used during the scientific sampling [data type: character]
ef_electrofishing_mean: mean used to realize the scientific sampling, by foot [data type: character]
density: density of eels collected, in nb/m2 [data type: numeric]
totalnumber: total number of eels collected [data type: numeric]
nbp1: number of eels collected during the 1st pass [data type: numeric]
nbp2: number of eels collected during the 2nd pass [data type: numeric]
nbp3: number of eels collected during the 3rd pass [data type: numeric]
nb_size_measured: number of measured eels [data type: numeric]
The individual level corresponds to the biological characteristics (length and weight) of the measured eels. The attributes associated with indivial are:

dp_name: name of data provider [data type: character]
ob_id: observation identifier [data type: UUID]
bc_id: batch (eels sampled during the observation) identifier [data type: UUID]
bc_ba_id: sub-batch identifier [data type: UUID]
size: total length of eel, in mm [data type: numeric]
fish_id: individual identifier [data type: UUID]
weight: body weight of eel, in g [data type: numeric]
The three tables can be related to each other through the identifiers, meaning that the eels measured in the individual table can be identified with the operations through the ob_id identifier, and these operations can be linked to the stations through the op_id identifier, allowing for a comprehensive view of the electrofishing sampling collected for Spain and Portugal.
4. VERSIONS

10.5281/zenodo.8009823 1.0.0 - 2023-06-06 - Initial upload (closed access)
10.5281/zenodo.8207785 1.0.1 - 2023-08-02 - Fixed data provider in station and operation tables (closed access)
10.5281/zenodo.8348353 1.0.2 - 2023-15-09 - Fixed stations (providers) (closed access)
10.5281/zenodo.8348353 1.0.2 - 2023-11-08 -  Final version (open access)
5. READ MORE

Atlas of European Eel Distribution (Anguilla anguilla) in Portugal, Spain and France (10.5281/zenodo.7546419)
Eel data (Anguilla anguilla) and associated environment variables used to fit the EDA model in the SUDOE area (SUDOANG project) (10.5281/zenodo.6397009)
Cumulated dam impact in France and the Iberian Peninsula (SUDOANG project) (10.5281/zenodo.8348374)
6. FUNDING
Project co-financed by the INTERREG SUDOE Programme through the European Regional Development Fund (ERDF).