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Non-indigenous species and Ballast Water Management

  3. Non-indigenous species and Ballast Water Management

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IMO · REMPEC · SPA/RAC

Ships take on seawater as ballast to stay stable and safe, then release it at the next port. With it travel bacteria, plankton, eggs, cysts and larvae from the other side of the world. Some survive, settle and become invasive. The IMO Ballast Water Management Convention sets the global rules to stop this, and the Ballast Water Management Strategy for the Mediterranean Sea (2022–2027) organises how the Mediterranean countries apply them together.

  1. 1991First IMO guidelinesMEPC.50(31)
  2. 1997IMO Assembly guidelinesA.868(20)
  3. 2004BWM Convention adoptedLondon · 13 February
  4. 2012First Mediterranean StrategyCOP 17 · Paris
  5. 2017Convention in force8 September
  6. 2021Strategy 2022–2027 adoptedCOP 22 · IG.25/17
  7. 2024Exchange phased outD-2 standard only
Diagram 1 · The pathway

How ballast water moves species between seas

Ballast water keeps a ship stable when it is empty or lightly loaded. It is pumped in where cargo is unloaded and pumped out where cargo is loaded, often thousands of kilometres away, together with everything living in it.

  1. 1

    Uptake at the source port

    The ship unloads cargo and pumps in local seawater. Plankton, larvae, eggs, cysts and microbes come aboard with it.

  2. 2

    The voyage

    Hardy organisms survive days or weeks in the dark tanks and in the sediment that settles at their bottom.

  3. 3

    Discharge at the destination port

    The ship loads cargo and releases its ballast. Most organisms die, but some establish and a few become invasive.

In one cubic metre of ballast water
50,000zooplankton organisms, up to
10 millionphytoplankton cells, up to
Ships carry species in two other ways
BiofoulingOrganisms attached to hulls, propellers and sea chests
Tank sedimentsA refuge for species such as dinoflagellate cysts

Organism figures from studies cited in the Mediterranean Strategy (2022–2027).

The Mediterranean context

A small sea with a large share of world shipping

The Mediterranean covers less than 1% of the world's oceans but carries just over 24% of global shipping, and most of that traffic is between Mediterranean ports. Corridors are the main entry route for non-indigenous species in the Eastern Mediterranean, while in the Western Mediterranean most introductions are linked to maritime transport, as stowaways in ballast water or on hulls.

24%of global shipping calls at or transits the Mediterranean
453,000port calls in 2019, by 14,403 ships
5,251ships transiting the area in 2019
1,011non-indigenous species recorded, 748 of them established

Shipping figures: REMPEC (2020), as cited in the Mediterranean Strategy. Non-indigenous species: 2023 MED QSR.

The global rules · IMO

The Ballast Water Management Convention

Concern about species carried in ballast water reached IMO's Marine Environment Protection Committee in the late 1980s, raised by Canada and Australia. After voluntary guidelines in 1991 and 1997, and more than 14 years of negotiation, the International Convention for the Control and Management of Ships' Ballast Water and Sediments was adopted by consensus in London on 13 February 2004. It entered into force on 8 September 2017, and its Parties now represent the vast majority of the world's fleet.

Ballast Water Management PlanCarried by every ship, specific to that ship
Ballast Water Record BookEvery uptake, treatment and discharge logged
Manage to a standardExchange (D-1), then treatment to the D-2 standard
Type-approved systemsBWMS Code, mandatory since October 2019
D-1

Ballast water exchange

An interim measure: ships swap coastal ballast for open-ocean water, where coastal organisms are less likely to survive.

  • 95% volumetric exchange
  • At least 200 nautical miles from land, in water at least 200 m deep
  • If not possible, at least 50 nautical miles from land, 200 m deep
  • Reduces the risk but does not remove it, and can compromise ship safety
  • No longer accepted from 2024
D-2

Ballast water performance standard

The standard every ship must now meet, usually with an approved treatment system. Discharged water must contain:

<10 / m³viable organisms ≥ 50 µm
<10 / mLviable organisms 10–50 µm
<1 cfutoxicogenic Vibrio cholerae per 100 mL
<250 cfuEscherichia coli per 100 mL
<100 cfuintestinal enterococci per 100 mL
The two standards of the Convention. Systems that use active substances also need a two-step IMO approval, reviewed by the GESAMP Ballast Water Working Group.

Article 13.3 of the Convention asks Parties that border enclosed and semi-enclosed seas, such as the Mediterranean, to cooperate regionally and develop harmonised procedures. The Mediterranean Strategy is that regional cooperation.

Infographic · Ratification in the Mediterranean

13 of 21 Mediterranean coastal States had ratified

13 / 21Mediterranean coastal States, Contracting Parties to the Barcelona Convention, party to the BWM Convention as of 21 April 2021

A 2016 assessment of the first Mediterranean Strategy found that only five of the responding countries had national law in place. Supporting ratification, and the laws that give it effect, is therefore the Strategy's first action.

Status as reported in the Mediterranean Strategy (2022–2027).

Diagram 2 · The Mediterranean Strategy 2022–2027

Three objectives, six priorities, twelve actions

The first Mediterranean Strategy was adopted at COP 17 in Paris in 2012 for 2011–2015, and its implementation continued after that. The entry into force of the Convention, its amendments, IMAP and the updated NIS Action Plan made it obsolete in several respects, and COP 22 adopted the updated Strategy for 2022–2027. Its focus remains ballast water, but its scope now extends to ship biofouling.

Objective 1A regional harmonised approach to ballast water control and management, consistent with the BWM Convention (Article 13.3)
Objective 2Start preliminary work on managing ships' biofouling in the Mediterranean
Objective 3Contribute to Good Environmental Status for non-indigenous species, as defined in IMAP
6strategic priorities12actions39activities, 2022–2027
Priority 1

Support ratification and implementation of the BWM Convention

  • A1Ratification of the BWM Convention4 activities
  • A2Harmonisation of BWM measures in the region8 activities
  • A3Port baseline surveys and biological monitoring4 activities
  • A4Risk assessment for ballast water decisions2 activities
  • A5Alignment with neighbouring regions1 activity
Priority 2

Contribute to Good Environmental Status

  • A6Ratification of the SPA/BD Protocol2 activities
  • A7Preliminary work on ship biofouling3 activities
  • A8Web-based Regional Information System2 activities
Priorities 3 to 6

Expertise, political will, review and resources

  • A9Capacity-building programme5 activities
  • A10Awareness among decision-makers and the public4 activities
  • A11Regular reviews of the Strategy3 activities
  • A12Resource mobilisation plan1 activity

Action 3 connects the Strategy to IMAP: one of its activities adapts the guidance for Common Indicator 6 so that port survey data flow into the IMAP Info System.

Diagram 3 · Exchange in the Mediterranean until 2024

Where ships should exchange ballast water

The Mediterranean is a semi-enclosed sea, so it is often impossible to be 200 nautical miles from land. Until exchange was phased out in 2024, the Strategy proposed regional arrangements for where ships should exchange ballast water.

  1. Entering or leaving the MediterraneanThrough Gibraltar or the Suez Canal: exchange outside the Mediterranean, at least 200 nautical miles from land in water 200 m deep, or at least 50 nautical miles if that is not possible.
  2. Sailing within the regionBetween Mediterranean ports, or to and from the Black Sea and the Red Sea: exchange as far from land as possible, always at least 50 nautical miles out in water 200 m deep.
  3. When neither is possibleUse exchange areas designated by the port State under IMO Guidelines G14, after consulting neighbouring States and notifying IMO.

If an exchange threatens the safety or stability of the ship, it is not carried out; the reason is recorded in the Ballast Water Record Book and reported to the port of destination.

Beyond ballast water

Biofouling: the other half of the shipping pathway

Organisms that grow on hulls, niches and sea chests travel with every ship, whether it carries ballast or not. To reach Good Environmental Status, the Strategy recognises that the whole shipping pathway must be managed, not ballast water alone.

The IMO's 2011 Biofouling Guidelines (resolution MEPC.207(62)) set the reference practice, and the GEF-UNDP-IMO GloFouling Partnerships project, launched in December 2018, supports countries in putting them into law and policy.

  1. Regional workshopTo start biofouling work in the Mediterranean
  2. National status assessmentsOf biofouling in each country
  3. National strategies and action plansTo manage biofouling
Who does what

A shared effort under the Barcelona Convention

REMPEC and SPA/RAC

REMPEC coordinates the Strategy, in cooperation with SPA/RAC, and both provide technical support to countries in synergy with IMO. Progress is reviewed at the meetings of the REMPEC Focal Points and the SPA/BD Focal Points, with a mid-term and a final review of the Strategy.

Contracting Parties

Countries ratify and apply the Convention, survey their ports, report ballast water data and build national capacity. Potential funding sources include the Mediterranean Trust Fund, IMO technical cooperation, the shipping and port industries and donors.

SPA/BD ProtocolArticle 13 on non-indigenous species NIS Action PlanPathways beyond shipping, in tandem with this Strategy IMAPCommon Indicator 6 and port monitoring Explore NIS dataRecords in MAMIAS
Sources
  1. International Maritime Organization, Ballast Water Management. imo.org
  2. REMPEC, Ballast Water Management Strategy. rempec.org
  3. UNEP/MAP, Decision IG.25/17, Ballast Water Management Strategy for the Mediterranean Sea (2022–2027), COP 22, 2021. Document
  4. UNEP/MAP, 2023 Mediterranean Quality Status Report (MED QSR), for all figures on non-indigenous species. medqsr2023.info-rac.org