Fish health checks

Guidance for fish suppliers and fishery owners on fish health checks.

Applies to England

Fish health checks are done to help protect fish and the water environment from harmful parasites and disease.

For fish that will be stocked, a sample of fish are selected for a health check. The check involves an internal and external examination to look for parasites and signs of disease.

A health check will not guarantee fish are disease free, but it greatly reduces the risk of introducing anything harmful to fisheries and the environment.

When you need a fish health check

You must get a fish health check if it’s a condition of your:

If you do not get the fish health checked before stocking a water that requires one, you may be prosecuted.

If a health check is not a permit condition, it’s still better that the fish you supply or buy have been checked as they may be carrying harmful parasites or disease.

Get a fish health check

You must use an approved fish health consultant to get a fish health check. Charges will vary.

Fish health checks are valid for:

  • 6 months for coarse fish
  • 12 months for farmed trout and salmon

Select fish for a health check

Fish you select for a health check must be representative of the fish that will be stocked. There are rules about the species, number and size of fish that need to be examined (known as ‘Fish size rules for health checks’).

Fish size rules for health checks (PDF, 91.5 KB, 3 pages)

In summary, you must submit a minimum of:

  • 30 fish in total
  • 10 fish of each species intended for stocking
  • 5 fish from each size category of species intended for stocking

You can deliver the fish to the consultant yourself, or use a courier. Some consultants may do the check at your fishery.

Fish health check results

You must send the fish health check results by email, fax or post to the Environment Agency Fish Movements team before any fish are introduced. This is a condition of all supplier permits.

It’s important you understand the results and discuss any concerns with your consultant.

If the fish pass the health check

You can stock the fish, but you must also comply with the other conditions in your supplier permit or site permit.

If the fish fail the health check

You may not be able to move fish off of your farm or out of your fishery if they fail a health check.

If the fish have one of the following parasites or diseases they will fail the health check:

  • Category 2 parasites and diseases
  • novel parasites and diseases
  • ‘clinical infection’ of any parasites or disease (parasites in high enough numbers to cause harm or signs of bacterial, fungal or viral infection)

Category 2 parasites and diseases are generally not native to fish in England and can cause serious problems in a fishery. Novel parasites and diseases are generally not widespread and their impacts are unknown.

You must check what the implications are for a failed health check. See the information on the specific parasites and diseases to confirm the restrictions.

Category 2 parasites

Category 2 parasites and diseases are:

  • Ergasilus sieboldi
  • Ergasilus briani
  • Ergasilus gibbus
  • Pomphorhynchus tereticollis (formerly identified as Pomphorhynchus laevis)
  • Anguillicoloides crassus
  • Monobothrium wageneri
  • Schyzocotyle acheilognathi (formerly known as Bothriocephalus acheilognathi)

Fish infected with these parasites can only be moved into fully enclosed waters, or waters that already have a confirmed infection of the same parasite. The site permit contains this information for the water that fish are being introduced to.

Novel parasites and diseases

Novel parasites and diseases are:

  • Lernaea cyprinacea
  • Pellucidhaptor pricei
  • Tracheliastes polycolpus
  • Tracheliastes maculatus
  • Philometroides sanguineus
  • Carp Edema Virus (CEV)
  • Anguillid herpesvirus-1 (AngHV-1) (formerly known as Herpesvirus anguillae - HVA)
  • Lactococcus garvieae

Fish infected with these parasites or carrying these diseases cannot be moved to any other waters. The Environment Agency will refuse applications to remove fish from infected waters for restocking.

The current controls for the viruses CEV and AngHV-1 and bacterium Lactococcus garviae are based on confirmation of these pathogens during disease outbreaks. A health check does not routinely check for these pathogens.

Contact the Fish Health, Ageing and Species team for more information on health check procedures or findings, including Category 2 or novel parasites and diseases.


Environment Agency Fish Movements team


Fax: 0207 714 2576

Telephone: 0208 474 5243

Environment Agency
Fish Movements team
Bromholme Lane
PE28 4NE

Monday to Friday, 9am to 5pm (answerphone outside these hours)

Environment Agency Fish Health, Ageing and Species team


Telephone: 0208 474 5244

Monday to Friday, 9am to 5pm (answerphone outside these hours)

Published 16 May 2014
Last updated 15 January 2018 + show all updates
  1. Guidance revised throughout to provide greater clarity to fish suppliers and fishery owners.

  2. Telephone number for the Environment Agency fish health team changed to 0208 474 5244.

  3. Environment Agency fish movements team (authorisations) telephone number changed to 0208 474 5243.

  4. Updated because of new fish movement legislation

  5. First published.