Dossier:
not provided by us yet
WelfareCheck:
F (2026-01-20)
Advice:
not provided by us yet
Profile status
Taxonomy
Ethograms
In the wild:
not investigated by us yet
Farm/lab:
not investigated by us yet
Catch/lab:
not investigated by us yet
Habitat
Growth
Length:
not investigated by us yet
Weight:
not investigated by us yet
Maturity:
no data found yet
Malformations:
Fyes
Swimming
Reproduction
Nest building:
no data found yet
Courtship:
no data found yet
Mating type:
no data found yet
Brood care:
no data found yet
Handling
Farming remarks
Ctenopharyngodon idella is a freshwater carp found in riverbeds with strong currents that feeds on higher aquatic plants and submerged grasses, also taking detritus, insects, and other invertebrates. It naturally inhabits lakes, rivers, and reservoirs of Eastern China and Russia in eastern Siberia and the Amur River system. This species is one of the four Chinese major carps – together with Hypophthalmichthys molitrix, H. nobilis, and Mylopharyngodon piceus – and among the most important species cultured in inland water bodies in China. It is considered as a major farmed freshwater species in the world which has been introduced into more than 50 countries for aquaculture and aquatic weed control. Despite that, several countries report adverse ecological impact after introduction.
In aquaculture, this species is usually farmed in polycultures in ponds and pen and cage culture in lakes and reservoirs. Consumers appreciate this carp for its lack of fine inter-muscular bones. Farmers value some advantages for aquaculture, such as fast growth rate, large size, feeding habits, and tolerance of a wide range of temperatures, salinities, and oxygen levels. C. idella is susceptible to disease, though, and stressed by common farming procedures. Further research is needed on wild information related to depth, reproduction, and aggregation, besides aggression, malformations, and a slaughter protocol in farms. Carp welfare can be improved using pond culture systems promoting a natural habitat and behaviour of the species.
For details see: WelfareCheck | farm (latest major release: 2026-01-20)
Related news
2026-01-20: Update WelfareCheck | farm: Ctenopharyngodon idella
Ctenopharyngodon idella, the Grass carp, is one of the four major Chinese carps. We had published the previous version of the WelfareCheck in 2017 and now gave it its due update according to our current scoring and formatting rules. Thanks to newly inserted papers, we were able to upgrade a lot of the Certainty values from Low to Medium which means that we are more secure in our scorings of the probability for good welfare under minimal and high-standard farming conditions. There is nevertheless research missing in almost all criteria to be fully certain of how well C. idella may be.
Even though there are possibilities to improve the sitation for C. idella in a lot of criteria, we assessed that in only 3 criteria, good welfare may be achieved under high-standard farming conditions. Exceptionally large ponds may cover the daily space needs of the species; if supplied with enrichment, ideally vegetation, ponds will satisfy the substrate use; and aggression is most likely no issue given enough food and the right partners for polyculture. Whether more criteria can achieve this benevolent scoring, future research will tell.
If you know of papers that can inform our evaluation, or if you have other comments, please get in touch!
Ctenopharyngodon idella
❮
❯
1 / 6
2 / 6
3 / 6
4 / 6
5 / 6
6 / 6
Profile
What does "not investigated by us yet" mean?
The centre of the Overview is an array of criteria covering basic features and behaviours of the species. Each of this information comes from our literature search on the species. If we researched a full Dossier on the species, probably all criteria in the Overview will be covered and thus filled. This was our way to go when we first set up the database.
Because Dossiers are time consuming to research, we switched to focusing on WelfareChecks. These are much shorter profiles covering just 10 criteria we deemed important when it comes to behaviour and welfare in aquaculture (and lately fisheries, too). Also, WelfareChecks contain the assessment of the welfare potential of a species which has become the main feature of the fair-fish database over time. Because WelfareChecks do not cover as many criteria as a Dossier, we don't have the information to fill all blanks in the Overview, as this information is "not investigated by us yet".
Our long-term goal is to go back to researching Dossiers for all species covered in the fair-fish database once we set up WelfareChecks for each of them. If you would like to support us financially with this, please get in touch at ffdb@fair-fish.net
What is the difference between "not investigated by us yet" and "no data found yet"?
See the question "What does "not investigated by us yet" mean?". In short, if we have not had a look in the literature - or in other words, if we have not investigated a criterion - we cannot know the data. If we have already checked the literature on a criterion and could not find anything, it is "no data found yet". You spotted a "no data found yet" where you know data exists? Get in touch with us at ffdb@fair-fish.net!
General
How to use the FAQ?
First up, you will find answers to questions for the specific page you are on. Scrolling down in the FAQ window, there are also answers to more general questions. Explore our website and the other sub pages and find there the answers to questions relevant for those pages.
How do I navigate in the fair-fish database?
In the fair-fish database, when you have chosen a species (either by searching in the search bar or in the species tree), the landing page is an Overview, introducing the most important information to know about the species that we have come across during our literatures search, including common names, images, distribution, habitat and growth characteristics, swimming aspects, reproduction, social behaviour but also handling details. To dive deeper, visit the Dossier where we collect all available ethological findings (and more) on the most important aspects during the life course, both biologically and concerning the habitat. In contrast to the Overview, we present the findings in more detail citing the scientific references.
Depending on whether the species is farmed or wild caught, you will be interested in different branches of the database.
Farm branch
Founded in 2013, the farm branch of the fair-fish database focuses on farmed aquatic species.
Catch branch
Founded in 2022, the catch branch of the fair-fish database focuses on wild-caught aquatic species.
What is the farm branch?
The heart of the farm branch of the fair-fish database is the welfare assessment – or WelfareCheck | farm – resulting in the WelfareScore | farm for each species. The WelfareCheck | farm is a condensed assessment of the species' likelihood and potential for good welfare in aquaculture, based on welfare-related findings for 10 crucial criteria (home range, depth range, migration, reproduction, aggregation, aggression, substrate, stress, malformations, slaughter).
For those species with a Dossier, we conclude to-be-preferred farming conditions in the Advice | farm. They are not meant to be as detailed as a rearing manual but instead, challenge current farming standards and often take the form of what not to do.
What is the catch branch?
In parallel to farm, the main element of the catch branch of the fair-fish database is the welfare assessment – or WelfareCheck | catch – with the WelfareScore | catch for each species caught with a specific catching method. The WelfareCheck | catch, too, is a condensed assessment of the species' likelihood and potential for good welfare – or better yet avoidance of decrease of good welfare – this time in fisheries. We base this on findings on welfare hazards in 10 steps along the catching process (prospection, setting, catching, emersion, release from gear, bycatch avoidance, sorting, discarding, storing, slaughter).
In contrast to the farm profiles, in the catch branch we assess the welfare separately for each method that the focus species is caught with. In the case of a species exclusively caught with one method, there will be one WelfareCheck, whereas in other species, there will be as many WelfareChecks as there are methods to catch the species with.
Summarising our findings of all WelfareChecks | catch for one species in Advice | catch, we conclude which catching method is the least welfare threatening for this species and which changes to the gear or the catching process will potentially result in improvements of welfare.
What do we mean by "welfare"?
Welfare of aquatic species is at the heart of the fair-fish database. In our definition of welfare, we follow Broom (1986): “The welfare of an individual is its state as regards its attempts to cope with its environment.” Thus, welfare may be perceived as a continuum on which an individual rates “good” or “poor” or everything in between.
We pursue what could be called a combination of not only a) valuing the freedom from injuries and stress (function-based approach) but b) supporting attempts to provide rewarding experiences and cognitive challenges (feelings-based approach) as well as c) arguing for enclosures that mimic the wild habitat as best as possible and allow for natural behaviour (nature-based approach).
What if I have a question?
Try mousing over the element you are interested in - oftentimes you will find explanations this way. If not, there will be FAQ on many of the sub-pages with answers to questions that apply to the respective sub-page. If your question is not among those, contact us at ffdb@fair-fish.net.
Where is the FishEthoBase?
It's right here! We decided to re-name it to fair-fish database for several reasons. The database has grown beyond dealing purely with ethology, more towards welfare in general – and so much more. Also, the partners fair-fish and FishEthoGroup decided to re-organise their partnership. While maintaining our friendship, we also desire for greater independence. So, the name "fair-fish database" establishes it as a fair-fish endeavour.
Frequently asked questions
«