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VME Criteria

As defined in the International Guidelines for the Management of Deep-sea Fisheries in the High Seas (FAO 2009). 

“A marine ecosystem should be classified as vulnerable based on the characteristics that it possesses. The following list of characteristics should be used as criteria in the identification of VMEs.” (Paragraph 42, FAO DSF Guidelines).



Uniqueness or rarity

An area or ecosystem that is unique or that contains rare species whose loss could not be compensated for by similar areas or ecosystems. These include:

  • habitats that contain endemic species;
  • habitats of rare, threatened or endangered species that occur only in discrete areas; or
  • nurseries or discrete feeding, breeding, or spawning areas.

Functional significance of the habitat

Discrete areas or habitats that are necessary for the survival, function, spawning/reproduction or recovery of fish stocks, particular life-history stages (e.g. nursery grounds or rearing areas), or of rare, threatened or endangered marine species.


An ecosystem that is highly susceptible to degradation by anthropogenic activities.

Life-history traits of component species that make recovery difficult

Ecosystems that are characterized by populations or assemblages of species with one or more of the following characteristics:

  • slow growth rates;
  • late age of maturity;
  • low or unpredictable recruitment; or
  • long-lived.

Structural complexity

An ecosystem that is characterized by complex physical structures created by significant concentrations of biotic and abiotic features. In these ecosystems, ecological processes are usually highly dependent on these structured systems. Further, such ecosystems often have high diversity, which is dependent on the structuring organisms.

Annex (FAO DSF Guidelines 2009)

The following examples of species groups, communities, habitats and features often display characteristics consistent with possible VMEs. Merely detecting the presence of an element itself is not sufficient to identify a VME.

Examples of species groups, communities and habitat forming species that are documented or considered sensitive and potentially vulnerable to DSFs in the high-seas, and which may contribute to forming VMEs:

i) Certain coldwater corals and hydroids, e.g. reef builders and coral forest including: stony corals (Scleractinia), alcyonaceans and gorgonians (Octocorallia), black corals (Antipatharia) and hydrocorals (Stylasteridae);

ii) Some types of sponge dominated communities;

iii) Communities composed of dense emergent fauna where large sessile protozoans (xenophyophores) and invertebrates (e.g. hydroids and bryozoans) form an important structural component of habitat; and

iv) Seep and vent communities comprised of invertebrate and microbial species found nowhere else (i.e. endemic).

Examples of topographical, hydrophysical or geological features, including fragile geological structures, that potentially support the species groups or communities, referred to above:

i) Submerged edges and slopes (e.g. corals and sponges);

ii) Summits and flanks of seamounts, guyots, banks, knolls, and hills (e.g. corals, sponges, xenophyphores);

iii) Canyons and trenches (e.g. burrowed clay outcrops, corals);

iv) Hydrothermal vents (e.g. microbial communities and endemic invertebrates); and

v) Cold seeps (e.g. mud volcanoes for microbes, hard substrates for sessile invertebrates).