A full list of the traits, categories and their definitions are listed below.


small (S1) <10 mm
small-medium (S2) 10-50 mm
medium (S3) 50-100 mm
medium-large (S4) 100-300 mm
large (S5) >300 mm
Body Form
globulose (BF1) Round or oval (e.g. sea urchin, sponge, some bivalves)
vermiform, elongate (BF2) Worm-like or thin, elongate body form
dorso-ventral compressed (BF3) Species that are flat, or encrusting (e.g. starfish, sponge)
laterally compressed (BF4) Thin (e.g. isopods, amphipods, some bivalves)
upright (BF5) E.g. coral, basket star, sponge
calcareous (SK1) Skeleton material aragonite or calcite, e.g. bivalves
siliceous (SK2) Skeleton material silicate, e.g. siliceous sponges
chitinous (SK3) Skeleton material chitin, e.g. arthropods
cuticle (SK4) No skeleton but a protective structure like a cuticle, e.g. sea-squirts
none (SK5) No form of protective structure, e.g. sea slugs
fragile (F1) Likely to crush, break, or crack as a result of physical impact (e.g. brittle star, soft worms, smaller crustaceans, mollusks with thin shells)
intermediate (F2) Liable to suffer minor damage, chips or cracks as result of physical impacts (e.g. mollusks with thicker shells, animals with harder cuticle like some echinoderms)
robust (F3) Unlikely to be damaged as a result of physical impacts, e.g. hard or tough enough to withstand impact, or leathery or wiry enough to resist impact (e.g. starfish, sponges, tunicates)
solitary (SO1) Single individual
gregarious (SO2) Single individuals forming groups; growing in clusters (e.g. barnacles)
colonial (SO3) Living in permanent colonies (e.g. stony corals, Bryozoa, Synascidia)

Life History

asexual (R1) Budding and fission (e.g. sponges, cnidarians)
sexual – external (R2) Fertilization external, eggs & sperm deposited on substrate or released into water (broadcast spawners) (e.g. echinoderms, cnidarians)
sexual – internal (R3) Fertilization internal, but no brooding, eggs deposited on substrate, indirect or direct development (e.g. gastropods)
sexual - brooding (R4) Fertilization internal or external, Eggs or larvae are brooded, indirect or direct development (e.g. amphipods, isopods, echinoderms)
Larval development
pelagic/planktotrophic (LD1) High fecundity, larvae feed and grow in water column, generally pelagic for several weeks (e.g. echinoderms, bivalves)
pelagic/lecithotrophic (LD2) Medium fecundity, larvae with yolk sac, pelagic for short periods (e.g. tunicates)
benthic/direct (LD3) Larvae have benthic or direct development (no larval stage, eggs develop into miniature adults)
Life span
short (A1) <2 years
medium (A2) 2-5 years
medium-long (A3) 5-20 years
long (A4) >20years


Living habit
free living (LH1) Not limited to any restrictive structure at any time. Able to move freely within and/or on the sediments.
crevice dwelling (LH2) Adults are typically cryptic, inhabiting spaces made available by coarse/rock substrate and/or biogenic species or algal holdfasts.
tube dwelling (LH3) Tube may be lined with sand, mucus or calcium carbonate, tube can also be in a burrow
burrowing (LH4) Species inhabiting permanent or temporary burrows in the sediment, or are just burrowing in the sediment
epi/endo zoic/phytic (LH5) Living on or in other organisms.
attached (LH6) Adherent to a substratum.
Adult movement
sessile/none (MV1) No movement as adult (sponge, coral)
burrower (MV2) Movement in the sediment (e.g. annelids, echinoderms, crustaceans, bivalves); including tube dwellers.
crawler (MV3) An organism that moves along on the substratum via movements of its legs, appendages or muscles (e.g. crab, snail)
swimmer (facultative) (MV4) Movement above the sediment (e.g. Amphipoda)
none (MO1) No movement as adult (sponge, coral)
low (MO2) Slow movement (e.g. anemones, some polychaetes, burrowing organisms)
medium (MO3) Medium movement (e.g. starfish, brittle stars)
high (MO4) High movement, swimmer or fast crawler (e.g. crabs, shrimps)
Feeding Habit
surface deposit feeder (FH1) Active removal of detrital material from the sediment surface. Includes species which graze or scrape algal matter from surfaces.
subsurface deposit feeder (FH2) Removal of detrital material from within the sediment matrix (e.g. Echinocardium)
filter/suspension feeder (FH3) Sponge, coral, hydrozoa, bivalves
opportunist/scavenger (FH4) An organism that can use different types of food sources/an organism that feeds on dead organic material (e.g. crabs, whelks)
predator (FH5) An organism that feeds by preying on other organisms (e.g. starfish).
parasite/commensal/symbiotic (FH6) An organism that lives in or on another living organism (the host), from which it obtains food and other requirements; or an organism containing symbionts.
Trophic Level
1 (TL1) Primary producer
2 (TL2) Primary consumers – Herbivore / Deposit Feeder /Suspension Feeder
3 (TL3) Secondary consumers – Carnivore
4 (TL4) Tertiary consumers
5 (TL5) Quaternary consumers – Apex predator
Substratum Affinity
soft (SA1) Soft substrata, sand or mud
hard (SA2) Hard substrata, rock, gravel
biological (SA3) Epizoic or epiphytic life style
none (SA4) Species is hyper/supra benthic and has no affinity for a certain substrate, but it might prefer one for hunting/scavenging (this category should not occur too often, as we work with benthos)
diffusive mixing (B1) Surficial movement of sediment and/or particles, resulting from movement or feeding activities on the surface.
surface deposition (B2) Deposition of particles at the sediment surface resulting from e.g. defecation or egestion (pseudofaeces) by, for example, surface deposit feeding organisms (e.g. holothuroids, bivalves, tubicolous polychaetes)
conveyor belt transport (upward) (B3) Translocation of sediment and/or particulates from depth within the sediment to the surface during subsurface deposit feeding or burrow excavation.
downward (reverse) conveyor (B4) The subduction of particles from the surface to some depth by feeding or defecation.
none (B5) No bioturbation (e.g. sessile animals on rocky ground).
low (T1) Species reacts sensitive to changes in the environment like organic enrichment, pollution, temperature or salinity changes; AMBI group I
intermediate (T2) Species react indifferent or no information available; AMBI group II
high (T3) Species tolerates organic enrichments, pollution, temperature or salinity changes; AMBI groups III-IV
Environmental position
infauna (EP1) Lives in the sediment.
epibenthic (EP2) Lives on the surface of the seabed.
hyper-benthic (EP3) Living in the water column, but (primarily/occasionally) feeds on the bottom; bentho-pelagic.
Depth Range
shallow (DR1) 0-20 m
shelf (DR2) 20-200 m (some shelves can extend to 500 m)
shelf-slope (DR3) 200-1000 m (sometimes the slope starts deeper, e.g. 500-)
slope-basin (DR4) > 1000 m
arctic (Z1) Confined to Arctic regions.
arctic-boreal (Z2) Arctic, sub-Arctic and North Atlantic/North Pacific distribution.
boreal (Z3) North Atlantic and/or North Pacific distribution; potentially sub-Arctic regions such as Southern Barents Sea or Bering Sea.
cosmopolite (Z4) cosmopolite distribution