fish
Let an agent handle fish as animals, as a caught or farmed resource, and as food, keeping those three readings apart because each carries different rules.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify
Researched by: Claude
Purpose and description
Let an agent handle fish as animals, as a caught or farmed resource, and as food, keeping those three readings apart because each carries different rules.
An aquatic vertebrate that breathes with gills and moves with fins, covering several distinct lineages that are not a single branch of the tree of life.
What it is for: Nothing in itself. To people fish are food, catch, stock, pets and an indicator of the state of a water body.
It can be observe and identify them, mostly in poor visibility; catch them, under quota and season rules; farm them, which is a different regulated activity; eat them, with contamination and allergen questions attached; kill them by changing the water, which is how most fish deaths happen.
Distinguishing features
Gill-breathing and aquatic throughout life, which separates fish from aquatic mammals and from amphibians
Not a single lineage: jawless, cartilaginous and bony fish are as distinct from each other as any of them is from a mammal
The animal, the catch and the food are three different regulated things
Wild and farmed individuals of one species are treated differently by almost every rule
What it looks like
A streamlined body with fins and, in most, scales; from a few millimetres to several metres. The visible form says more about how the fish swims and where it lives than about its relatedness.
Physical character
length: 0.01-7 m - the range spans the smallest vertebrates to the largest sharks
tolerated temperature: -2 to 40 C - species-specific and narrow for most
dissolved oxygen requirement: 4-8 mg/L - the usual cause of a fish kill is this falling, not poisoning
How it is recognised
Fin arrangement and count, which is the basis of most identification keys
Body shape and mouth position, which indicate feeding habit and habitat layer
Colour, which is unreliable: it changes with age, season, breeding state and after death
For a fish on a slab, the head and fins are removed exactly where identification would happen
Related models
is a kind of - inherits taxonomy, welfare and conservation questions
becomes - once landed it enters a different regime with different facts attached
lives in - its condition is largely the condition of the water
regulated by - quota, season, gear and minimum size
is confused with - seafood includes molluscs and crustaceans, which are not fish
In practice
Families and kinds
by lineage: jawless, cartilaginous, ray-finned, lobe-finned
by water: freshwater, marine, diadromous
by origin: wild-caught, farmed, ornamental, stocked
by trade form: whole, gutted, filleted, processed
Identifiers
accepted binomial genus species identifies the species
FAO species code 3 letters used in catch and trade statistics
catch or batch identifier fishery-specific what traceability rules actually track
Standards and regulation
Fisheries management measures: quota, closed seasons, minimum landing size, gear restriction
Aquaculture regulation, covering welfare, medicines and escapes
Food safety rules for fishery products, including histamine and parasite controls
CITES and protected species listings for some sharks and sturgeons
Failure modes and hazards
Fish kills from low oxygen, temperature or pollution, which affect a whole water body at once
Overfishing, where the failure is of the stock rather than of any individual
Parasites and biotoxins, which are food safety hazards specific to fish
Escape of farmed fish, which is an environmental incident
Mislabelling, which is common enough that species substitution is a routine fraud
Also called
+80
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.fish-food
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.
Taxon and identification What kind of fish, and how that was established.
Species determines quota, protection and food rules, and it is often not visually determinable in the state the fish is encountered.
Species and lineage
Accepted name and where it sits.
Accepted name and its lineage
The name, the authority, and which major group it belongs to.
- What species is this, under which accepted name, and in which lineage? definition
- What evidence supports the identification, given the state the fish is in? provenance
Substitution risk
Which species are sold as this one.
Known substitutions
Species commonly passed off as this one and how they are told apart.
- Which species are commonly substituted for this one in trade? boundary
- What test settles the question when the diagnostic parts have been removed? action
Stock and population The group this fish belongs to and its state.
Fisheries rules act on stocks, not on fish, and a stock is a management unit rather than a biological one.
Stock unit
How the management unit is defined.
Stock definition
The unit, who defines it, and its boundary.
- Which stock does this fish belong to, and who defines that stock? definition
- Where does the stock boundary sit, and how is that decided? boundary
Stock state
Assessment, quota and trend.
Assessed state of the stock
The assessment, its date and what it permits.
- What is the assessed state of this stock, by whom and for which year? provenance
- What catch does that permit, and what must an agent refuse to plan? action
Welfare and handling Keeping, catching and killing.
Handling determines both welfare and quality, and the two are governed by different rules that both attach to the same acts.
Holding conditions
Water quality, density and what a living fish needs.
Conditions required
What must be true of the water for the fish to live.
- What water conditions does this species require, in what ranges? measurement
- Which single parameter, if it drifts, kills fastest? boundary
Capture and slaughter
Gear, handling and killing method.
Method and its constraints
What is permitted, and what it does to welfare and quality.
- Which capture and slaughter methods are permitted for this species and setting? definition
- What must be recorded about handling for the catch to be tradeable? provenance
As food What happens after landing.
At landing the fish stops being an animal in law and becomes a food, with a new set of facts that the animal model does not carry.
Food safety
Parasites, biotoxins, histamine and contaminants.
Hazards specific to fish
What must be controlled before it may be eaten.
- Which food safety hazards apply to this species, and what control removes each? definition
- What evidence shows the control was applied? provenance
Traceability and labelling
What must be declared and what it proves.
Declared origin and method
The information that must travel with the fish.
- What must be declared about this fish - species, area, gear, farmed or wild? definition
- What may a buyer not infer from that declaration? boundary
What the second pass must settle
- Should stock, species and individual be separate models, given that management applies to stocks?
- How should the transition from animal to food be represented, since the same object changes regime at landing?
- What evidence should an agent require before accepting a species claim on a processed product?