Database & Atlas of Freshwater Fishes

Freshwater fishes (including anadromous* species) are the only vertebrate group for which, hitherto, there has not been an up-to-date collated source of information on the distribution of species in the UK. Several species of freshwater fishes occurring in the UK are listed for protection under national or international legislation / conventions. Information on the distribution of these species as well as more common species is therefore of great interest to many different groups of people such as conservationists, naturalists and anglers. The DAFF project has produced a collated information source on the distribution of all freshwater and estuarine fish species for Britain.

As this project covered a large geographical area, BRC has collated existing sets of data rather than individual records. The Environment Agency has made available all survey data for inclusion and data have been acquired from a variety of other sources. For rare or alien species, however, individual records have also be included as long as they met minimum data criteria.

In order for records to be included in the DAFF database, there was a certain minimum amount of data required: species name, grid reference, locality (water body name and / or location name), and date (at least year) are the minimum requirements and as records must be validated rather than anecdotal, the name and address of the person who supplied the information and confirmed the identity of the species.

* Anadromous species: species which ascend rivers from the sea to spawn

History of the DAFF Project

In 1995/96 the national Biological Records Centre (BRC) jointly funded by the Institute of Terrestrial Ecology (ITE) and the Joint Nature Conservation Committee (JNCC) undertook a feasibility study on the preparation of a national dataset and Atlas of freshwater fishes. ITE involved staff at its sister institute, the Institute of Freshwater Ecology (IFE), in this study. 

The study concentrated on the potential for collating relevant data from existing datasets and making greater use of these data, rather than attempting to set up new national-scale data-gathering initiatives. Most datasets are held by organisations rather than by individuals.

It was concluded in the feasibility study that it would be practicable to compile a national summary database and prepare an Atlas, given the willingness of the potential sources of data to contribute at least summary records and sufficient resources to carry out the work over a period of 3 to 5 years. Given the coverage achieved by Maitland (Key to British Freshwater Fishes FBA publ. no.27. 1972), and the amount of survey work done since then, it is not unreasonable to expect that coverage would be at least as good as that achieved for most 'popular' groups, other than birds. 

It was agreed that the database and atlas project should not initiate new surveys of freshwater fishes. Instead it should draw upon existing, dispersed datasets to collate a minimum set of data to answer a limited range of questions about where and when freshwater fishes have been recorded in the UK. After a period of time spent locating and obtaining suitable data sources, data collation began in earnest in 1998. Data collation was completed by at the beginning of 2002. The final report was produced in April 2002.   ‘Freshwater Fishes of Britain’,  containing 10km square distribution maps, species accounts and much more is expected to be published by Harley Books in 2003.

The database does not collate the full range and variety of data held in many different forms by potential contributors (DATA FIELDS). However, a summary index to relevant data (a form of metadata) has been compiled as part of the project, as each contributing source of data was examined. These metadata and summary distribution data will be available on the NBN Gateway.

Project Reports

C.E.Davies, P.T.Harding & H.R.Arnold 
Database and Atlas of Freshwater Fishes in the UK: Final Report.
April 2002: 88 pp.
Contract report to the Joint Nature Conservation Committee

Database and Atlas of Freshwater Fishes in the UK: Report on 2000/2001 Work Programme: 
March 2001. 85pp.
Contract report to the Joint Nature Conservation Committee

Davies, C.E., Cooper, J.M. & Harding, P.T.
Report on 1999/2000 Work Programme
March 2000
Contract report to the Joint Nature Conservation Committee 

Davies, C.E. & Harding, P.T.
Database and Atlas of freshwater fishes in the UK:  Report on 1998/99 Work Programme
April 1999
Contract report to the Joint Nature Conservation Committee 

Davies C.E., Harding, P.T. & Arnold, H.A.
Database and Atlas of freshwater fishes in the UK: 1997/98 Work Programme
Draft Report 
March 1998
Contract report to the Joint Nature Conservation Committee

Davies C.E. & Harding, P.T.
Database and Atlas of freshwater fishes in the UK: Pilot project 1996/97
June 1997
Contract report to the Joint Nature Conservation Committee

Data Fields for the DAFF Project

There is a certain minimum amount of data required before records can be included in the database; these are the essential fields listed below. In addition, the database collates other data which may be held in the source dataset; these fields are not present for all contributing datasets.


Dataset Name of dataset/survey etc.
Owner Owner of dataset
Species name1 Scientific name of species
English name1 English name of species
Grid reference National grid reference
Year Year of record
Collector2 Person who collected/caught the specimens
Identifier2 Person (or competent organisation) who identified the specimens
Compiler2 Person (or organisation) who compiled the dataset (may be same as above)
Waterbody name1 Name of river, lake etc.
Locality1 Place name on OS map or, e.g., near A111 road bridge, Xtown

1     At least one of these two fields must be included
2     At least one of these three fields must be included


More information about the sample

Day Day of record (blank if not recorded)
Month Month of record (blank if not recorded)
Day2 End date (day) if survey over a period
Month2 End date (month) if survey over a period
Year2 End date (year) if survey over a period
Source Source of record (Field survey / museum / published literature)

More information about the sample site and method

Site reference Survey site code or number (if used)
Catchment code Water catchment code
Sample location identifiers (e.g. netted from third tree south of bridge 40m downstream)
Sample method e.g. seine netting, electrofishing, etc.

More information about the species

Status Status of species – (native/introduced/escaped/self maintaining/restocked/unknown)
Species presence Confirmed presence or absence of a species at a site on given date
Population (qualitative) e.g. single specimen, rare, frequent, common, abundant etc.
Catch Number of specimens caught during sampling (includes ranges)
Population (quantitative) Quantitative population information (e.g. density, actual or estimated, and estimation method)
Biomass Quantitative biomass data
Breeding Yes / No (Evidence species is breeding at site – eggs or fry present)
Stage Life stage(s) of species present (eggs/fry/adult/male etc)

More information about the habitat

Waterbody type e.g. river, canal, pond, lake reservoir etc.
Habitat type (character) Brief description of habitat type
Substrate Main substrate type
Vegetation type General (not species lists) e.g. reed beds, floating vegetation
Depth Depth of water (units stated or qualified)
Area Area of still water body (units stated)
Length Length of sampled stretch of river etc. (units stated)
Current speed Speed of current - measured (state units)
Current (qualitative) Stagnant, slow, ... fast, etc.
Altitude Altitude (units stated)

Data Contributors

Public bodies

Private individuals

Anglian Water John Bratton
Argyll Fisheries Trust R Niall Campbell
BRC Barry Kirk
CEFAS Piers Langhelt
CEH Peter Maitland
Conon District Salmon Fishery Board Graeme Peirson
Department of Agriculture, Fisheries and Forestry (IoM) Matthew Smith
DETR / WWT Steve Young
Dee District Salmon Fisheries Board  
English Nature  
Environment Agency  
Environmental Records Centre for Cornwall and the Isles of Scilly  
Environmental Services, Jersey  
FRS Freshwater Laboratory  
Findhorn District Salmon Fishery Board  
Fish Conservation Centre  
Fisheries Research Services  
Freshwater Biological Association  
Galloway Fisheries Trust  
Guernsey Museums & Galleries  
Hampshire and Isle of Wight Wildlife Trust  
Kyle of Sutherland District Salmon Fishery Board  
Lochaber Fisheries Trust  
Lochaber and District Fisheries Trust  
National Coarse Fisheries Centre  
National Fisheries Laboratory  
Northumbrian Water Ltd.  
River Annan District Salmon Fisheries Board (RADSFB)  
Scottish Natural Heritage  
Scottish Office  
Sheffield City Museum  
Spey Research Trust  
Tay District Salmon Fisheries Board  
Thames Water  
Tweed Foundation  
West Sutherland Fisheries Trust  
Wester Ross Fisheries Trust  
Western Isles Fisheries Trust (WIFT)