A HIGHLAND pressure group has claimed the UK is now the only country bordering the North Sea not to have signed an international agreement to safeguard Scotland’s seas from pollution by alien organisms.

Cromarty Rising – which is fighting plans for ship-to-ship (STS) oil transfers in the Cromarty Firth – said the UK Government has not endorsed the International Maritime Organisation’s (IMO) convention on the control of ballast water, which prevents it coming into force.

There are plans for 8.4 million tonnes of crude oil a year to be transferred between tankers at the mouth of the Cromarty Firth, near important environmental sites in waters where dolphins live and breed. Concerns are rising that more than 2 million tonnes of untreated ships’ ballast water will be released into the firth.

Cromarty Rising said it had received expert guidance which had established that North Sea neighbours France, Germany, the Netherlands, Belgium, Denmark and Norway have already ratified the newest IMO Convention, which has been adding signatories since 2004 – but the UK Government has failed to.

Empty oil tankers use ballast water when they go out to sea empty, as a temporary weight to stabilise them between jobs. When the ship arrives at its destination terminal, it pumps out the ballast water in preparation for filling its tanks with crude oil.

A Cromarty Rising spokesman said this can endanger local waters: “If a ship takes on ballast water in one part of the world then releases it elsewhere, it discharges a diverse range of organisms within the sea water. These include bacteria, pathogens, eggs, cysts and larvae of non-native aquatic species.”

An example of a predatory non-native species is the killer shrimp, for which the UK Non Native Species Secretariat has already released an alert.

It is not actually a shrimp but a type of crustacean known as an amphipod and, at just over an inch long, has unusually large and powerful mouthparts to bite and shred its prey.

The IMO’s initial standard (IMO D1) only requires that a ship should change ballast water during its journey. Its newest convention (IMO D2) would require all ballast water to be treated before being dumped.

This will come in force when 30 IMO member states, representing 35 per cent of the world’s shipping tonnage have ratified it. Last month 51 had agreed, representing 34.87 per cent of global merchant shipping tonnage, leaving it 0.13 per cent short of becoming international law.

With a deadweight tonnage of more than 40 million, the UK is the world’s 10th largest merchant shipping nation, and had it signed the convention it would be part of global law.

Black Isle councillor Craig Fraser said: “How can we have any confidence in the MCA or the UK Government to take our concerns about oil transfers seriously, when they continually frustrate other nations’ efforts to fight the threat of marine pollution posed by ballast water.

“The Cromarty Firth ship-to-ship oil transfer licence indicates discharging 2 million tonnes of untreated ballast water when the Nigg oil terminal has the capability to treat this safely.”

A spokesman for the Maritime and Coastguard Agency (MCA) said the UK fully supported the aims of the ballast water management convention and had chaired the negotiations that led to it.

It had not ratified it while the IMO continued to work on outstanding matters concerning sampling, analysis and testing of ballast water and the method of approval for treatment systems.

The spokesman added: “The outstanding issues regarding sampling and analysis of ballast water, in particular the ability to take representative samples and to test them to ensure compliance, are a concern as failure to resolve these matters could result in a lack of harmonisation in enforcement around the world and undermine the overall goal of the convention to address the risk of invasive species.

“Progress continues to be made at IMO where the shipping and scientific communities are working to find pragmatic and practicable solutions and the UK Government is playing a leading role in this work chairing the Correspondence Group on Ballast Water that is addressing the matter.”