Commercial fishery for razor clams using electric current gear consultation: strategic environmental assessment screening
A screening determination report of the environmental effects associated with the outcomes expected from the planned consultation on a commercial fishery for razor clams in Scotland.
16. Identifying interactions of the pan with the environment and considering the likely significance of any interactions
16.1 Plan component: Outcome 1 Returning to general prohibition
16.1.1 Environmental topic areas
- Biodiversity, flora and fauna
- Population and human health
- Material assets
16.1.2 Explanation of potential environmental effects
Prohibition has a high likelihood of causing a return to widespread IUU fishing. Any businesses that opt not to engage in IUU fishing are likely to be put into financial distress leading to the disposal of some vessels, business premises and equipment.
16.1.3 Explanation of significance
It is difficult to speculate on the potential environmental impact of IUU fishing. It would encompass: fishing with no regard to safe harvesting levels, fishing with no regard to impacts on protected species or habitats, fishing with no regard to food safety or workforce safety. It would inevitably attract a significant enforcement resource allocation, which would mean diminished oversight of other fisheries enforcement priorities. Prior to the establishment of the trial this took the form of non-productive anchoring of fisheries protection vessels to discourage fishing, at significant annual cost (~£1.8 million in 2016).
16.2 Plan component: Outcome 2 Continuing the trial in some capacity
16.2.1 Environmental topic areas
- Biodiversity, flora and fauna
16.2.2 Explanation of potential environmental effects
By the time the trial has concluded it will have been firmly established that sustainable harvesting is possible in two areas (Forth and Clyde), and new assessments will be published for further areas. There would therefore need to be a new scientific reason to authorise continued fishing in the Forth and Clyde, and if none are forthcoming, considering closing these areas to fishing. This would likely prompt a degree of IUU fishing to resume, though not to the same extent as outcome 1.
For areas where continued fishing was authorised, the scientific benefit of further insights would be balanced against the effect on razor clam populations and the wider ecosystem of sustained fishing over a long period in a small area. This may introduce overexploitation.
16.2.3 Explanation of significance
Currently, our assessment is that fishing pressure is below estimated FMSY in all areas for which we have complete or preliminary stock assessments. If the trial were to continue, some grounds may have been consistently fished for a decade, when fishers might otherwise have rotated grounds to avoid overexploitation. We have not made an assessment of when this point may be reached in future so cannot comment on the potential significance of this component. It is reasonable to assume, given the knowledge gained during the trial on growth rates and repopulation following fishing removals, that continued fishing effort in a small area over the long term is likely to risk harm to populations at some level that may interfere with the anticipated insights to be gained from authorising further fishing.
16.3 Plan component: Outcome 3 establishing a commercial fishery
16.3.1 Environmental topic areas
- Biodiversity, flora and fauna
16.3.2 Explanation of potential environmental effects
Any commercial fishery that emerged from the trial, if Ministers opted to pursue such a policy, would require appropriate management measures to avoid:
- Overexploitation
- Adverse impacts on protected species or habitats
Benefits of such an approach would be reduced likelihood of significant IUU fishing activity and suitable regulation of the above impacts.
16.3.3 Explanation of significance
Razor clams are relatively long-lived and take around 7 years to reach their maximum size. As a sedentary burrowing species they are vulnerable to overexploitation. The commercial fishery in Ireland which uses dredges is thought to be more efficient than electric current, removing approximately 90% of clams per fishing operation compared to approximately 80% with electric current gear. The Irish fishery is considered to be at risk of overexploitation. Therefore without appropriate management measures this would be a real risk. Loss of mature clams would have some impact on ecosystem function, as sediment reworking by burrowing fauna is an important mechanism by which oxygen and organic matter are transported through sediments. Loss of reworking capacity could pose a risk of deoxygenation, reduction in seabed biodiversity and reduction in prey-supporting habitat for seabirds, fish and marine mammals.
Without knowledge on the extent of new fishing effort to be expected either from new vessels or from fishing new areas, it is difficult to establish the level of significance.
A fisheries assessment has been drafted that considers the current level of activity to be unlikely to have significant effects on most protected species identified as being potentially effected, and management through seasonal closures of particular areas is considered an effective way to permit fishing activity without compromising site-specific conservation objectives.