Like for the petroleum industry the maritime transport is another activity that could have a negative impact on the ecosystem when it comes to discharges of oil during an accident. An important subject to consider for development of ecosystem based management, like for the petroleum industry, is the question on how we deal with the risk for accident.
Accidental discharge
Human error is the predominant reason for accidents involving ships. Oil spills from maritime transport may be the result of groundings, collisions, structural errors or fire/explosion.
Oil and gas tankers will account for most of the increase in traffic in the Barents Seas in the near future. Exports of crude oil pose a significant risk of oil spills.
Implementation of measures such as a minimum sailing distance from the coast, traffic separation schemes and vessel traffic service centres will reduce the risk of accident and then the oil spills associated with maritime transport. As for the oil and gas industry the consequence of an accident will depend on the efficiency of the emergency oil spill response system.
Maritime transport currently involves a higher level of risk exposure in the Barents Sea than the expected risk exposure from all planned activities (Report no. 8 to the Storting). However, this conclusion is based on assumptions related to knowledge development, technological advances and the introduction of traffic separation schemes between 2006 and 2020 in line with existing plans in 2006, and may be affected by new, currently unplanned activities.
Despite the expected increase in the volume of maritime transport, the analyses indicate that the implementation of measures such as a minimum sailing distance from the coast for loaded oil tankers, traffic separation schemes and vessel traffic service centres will reduce the risk of major oil spills (>100 000 tonnes) associated with maritime transport.
Other factors that influence environmental risk are the position of the ship, the environmental value of the affected areas and the time of year when the oil spill occurs.
Introduction of alien species
Several new species in the maritime environment are a result of the discharge of ballast water.
International agreements on ballast water exchange and treatment, and the general increase in awareness of the problems associated with ballast water, are expected to reduce the risk of negative impacts. It is much more difficult to reduce the risk of introduction of alien species attached to ships’ hulls. This is because the most effective anti-fouling systems themselves have negative impacts on the environment.
Knowledge gaps
The need for knowledge connected to oil spill and the effect of it will be the same whether the oil came from the petroleum industry or from the maritime transport (see chapter Issues of importance for ecosystem based management - Oil and gas activities - Themes to consider when developing ecosystem based management).
In spite that the introduction of alien species is considered to be one of the most serious threats to the biodiversity in marine ecosystem to day we know little about the effects of alien species. Especially there are knowledge gaps concerning invasive species that may alter the structure of the whole ecosystem. When an alien species is established in a new are, history have shown us that there is little we can do to eliminate the new species.
