Publication - Consultation paper

2014 Consultation on the Management of Inshore Special Areas of Conservation and Marine Protected Areas Approaches.

Published: 11 Nov 2014
Part of:
Marine and fisheries
ISBN:
9781784128913

2014 Public Consultation on the Management of Inshore Special Areas of Conservation and Marine Protected Areas Approaches.

77 page PDF

570.7 kB

77 page PDF

570.7 kB

Contents
2014 Consultation on the Management of Inshore Special Areas of Conservation and Marine Protected Areas Approaches.
Protected Area Q - Wester Ross MPA

77 page PDF

570.7 kB

Protected Area Q - Wester Ross MPA

This section sets out 2 possible management approaches for this protected area. Under the 1 st approach further measures will be required for burrowed mud and circalittoral muddy sand communities. Approach 2 would deliver sufficient protection for all the protected habitats and species.

Approach 2 is preferred because it would deliver all the measures necessary.

A description of this protected area can be found in the main consultation document is Annex A, Protected Area Q. Maps to support understanding of the approaches can be found under Protected Area Q in the technical maps document. Figure Q1 shows Wester Ross in context with other protected areas. Figure Q2 shows the distribution of protected features within the MPA.

Measures for Wester Ross would be delivered by Statutory Instrument using powers under the Marine (Scotland) Act 2010, or the Inshore Fishing (Scotland) Act 1984.

Questions 45 to 49 refer to Wester Ross.

The site features and conservation objectives

Protected Feature

Conservation objective

Maerl beds

Recover

Flame shell beds

Recover

Maerl or coarse shell gravel with burrowing sea cucumbers

Conserve

Burrowed mud

Conserve

Circalittoral muddy sand communities

Conserve

Kelp and seaweed communities on sublittoral sediment

Conserve

Northern feather star aggregations on mixed substrata

Conserve

Summary of the management advice

Feature

Mobile gear

Static gear

Other gear

Maerl beds

Remove / avoid pressure from demersal trawl, mechanical dredges, or suction dredges

Consider reduce / limit pressure

Remove / avoid pressure from diver operated suction gear

Flame shell beds

Remove / avoid pressure from demersal trawl, mechanical dredges, or suction dredges

Consider reduce / limit pressure

Remove / avoid pressure from diver operated suction gear

Maerl or coarse shell gravel with burrowing sea cucumbers

Remove / avoid pressure from demersal trawl, mechanical dredges, or suction dredges

Remove / avoid pressure from diver operated suction gear

Burrowed mud

Reduce / limit pressure from demersal trawl, mechanical dredges, or suction dredges. (remove / avoid from aggregations of tall seapens)

Consider reduce / limit pressure

Circalittoral muddy sand communities

Reduce / limit pressure from demersal trawl, mechanical dredges, or suction dredges.

Kelp and seaweed communities on sublittoral sediment

Reduce / limit pressure from demersal trawl, mechanical dredges, or suction dredges.

Northern feather star aggregations on mixed substrata

Reduce / limit pressure from demersal trawl, mechanical dredges, or suction dredges.

Flame shell beds and maerl beds are highly sensitive to physical disturbance caused by mobile gears which can cause surface and sub-surface abrasion/penetration. Flame shell beds are affected directly through mortality from damage to the shells, by breaking up the bed and by affecting or removing associated fauna attached to the bed. The three dimensional structure, quality and associated communities of maerl beds can be substantially affected by mobile demersal gear fishing from crushing, burial of live maerl and disruption of the surface and underlying sediment.

Maerl beds have a low rate of recovery due to their very slow growth rate. In addition to direct impacts, flame shell beds and maerl beds are sensitive to increased levels of sedimentation which can be caused by passing mobile/active fishing gear, which causes smothering of the maerl/flame shells as well as associated fauna and flora. The deployment and retrieval of static gear over maerl beds has the potential to cause sufficient surface abrasion that would result in a detrimental effect.

However, the extent of these impacts on maerl beds would be dependent on the intensity of fishing. Whilst there is no published evidence on the sensitivity of flame shell beds to static gear, given their high sensitivity to abrasion and due to the delicate nature of their shells and the nests, intense levels of fishing with heavy static gear could have damaging effects.

Kelp and seaweed communities on sublittoral sediment have low to medium sensitivity to pressures associated with demersal mobile gear. Species of kelp and seaweed can be removed by passing trawls, dredges with low energy sites with dense kelp and seaweed coverage being the most sensitive. However, many animal species associated with the habitat are mobile or infaunal and so are likely to avoid most effects of surface disturbance. Northern feather star aggregations have medium sensitivity to pressures associated with demersal mobile gear e.g. surface abrasion and removal of species. The potential effects include direct mortality through capture or contact with gear and possible indirect effects from smothering and/or increased suspended sediment. The degree of effects will depend on the gear type, substrate composition and local hydrodynamic conditions.

Burrowed mud has medium sensitivity to physical pressures associated with mobile demersal fishing gear e.g. surface and sub-surface abrasion. Physical disturbance of surface of seabed is likely to affect mobile and sessile epifaunal and shallow burrowers, for example damage to seapen species is likely to take place as a result of greater sediment disturbance from towed demersal gear. Trawling for Nephrops can, by reducing the number and size of burrowing individuals present, also affect the habitat structure itself in terms of the number and size of burrows present. However, the degree of impact in terms of diversity and relative abundance of species is likely to be related to the intensity of fishing activity, and there is scope for recovery. For static gear, it is likely that when fishing activity is low, direct impact on the habitat is likely to be minimal and seabed structure is likely to be maintained in a slightly modified state. However the impacts of increasing static gear fishing intensity and the subsequent impacts on the habitat are less well understood.

The approaches to management

Recovery habitats

Wester Ross MPA has two of the four protected features in the network that have recovery conservation objectives. At present no specific management beyond measures for demersal trawl and mechanical dredge are proposed. Question 47 asks whether static gear fisheries, and other activities that cause similar seabed disturbance, should be restricted in areas essential to the recovery of the maerl beds and flame shell beds.

There is presently a voluntary fisheries management arrangement in place to ensure that no physical disturbance of the maerl beds takes place. Under either of the management approaches the fishing industry would like a similar depth zonation around the Summer Isles to enable a scallop dredge fishery to continue. Question 48 asks whether such an approach should be considered. It should be noted the risk of sedimentation effects would have to be assessed as part of devising such an approach.

Static gear assessment

Static gear activity is low to moderate according to Scotmap. The current levels are not considered to be impacting on the habitats. Subject to views on question 47, no additional static gear management is proposed. However if future studies found there to be a negative effect then this would be addressed then.

Measures common to both approaches

The use of suction dredges (boat or diver operated) would be prohibited throughout the MPA. The size of vessel which can fish in the MPA would be restricted to 150 Gross Registered Tonnage ( GRT). Under both approaches the existing seasonal closure in Little Loch Broom and Gruinard Bay would be replaced by a new permanent closure on a lesser boundary.

Approach 1

The approach would deliver zonal management for the protection of the maerl beds and flame shell beds. Further measures for burrowed mud and circalittoral muddy sand communities would be required.

Proposed measures

In addition to the common measures, the use of demersal trawls and mechanical dredges would be prohibited in the purple zones shown in figure Q3.

These could be described as follows;

Summer Isles
Horse Island
Eilean Dubh
Upper Loch Broom
Little Loch Broom and Gruinard Bay
West side of Loch Ewe

The benefits

The spatial measures would deliver the necessary protection for maerl beds and flame shell beds. In addition the areas with the most significant populations of tall sea pen would also be protected. The capacity restriction would go some way to limiting the pressure on the sedimentary habitats. The measures would further the conservation objectives of maerl beds and flame shell beds, but not for all features. This means that further measures (as part of the 2 nd batch) would be required for the other features

The costs

Method

Average annual MPA value

Average annual value affected

% of value affected

Average annual effort hours in MPA

Average annual effort hours affected

% of effort affected

Trawl

£313

£15

5%

4482

87

2%

Dredge

£39

£13

33%

454

132

29%

Table Q1: Average annual impact of approach 1 based on 2007 to 2013 data for over 15 metre vessels (rounded to nearest £000s)

Wester Ross covers part of ICES rectangles 44E4 and 44E5. According to the analysis of Scotmap data for trawl fisheries approximately 27% of the total value of those ICES Rectangles is taken from the MPA. Amount affected is based upon the effort proportion affected for trawling (2%) by over 15 metre vessels.

Method

Total effort days

Effort days affected

Total value

Value effected

Trawl

230

5

£283

£5.5

Table Q2: Average annual impact of approach 1 based on 2013 data for under 15 metre vessels (rounded to nearest £000s)

The displacement effects

The area around the Summer Isles is where most of the displacement would occur. There are other scallop grounds within the MPA (which do not have protected features) which would be available to these vessels as shown in figure Q7. In overall terms it does not represent a significant amount of effort.

Vessels over 150 GRT are more than capable of fishing on grounds outwith the MPA. There are significant areas of burrowed mud on the North Minch for these vessels to operate on, and consequently any displacement effect would be widely dispersed (see figure Q9).

Therefore there is unlikely to be any significant negative environmental effect.

Approach 2 (preferred approach)

The approach would deliver zonal management for all the habitats.

The proposed measures

No demersal trawling or mechanical dredging in the 5 areas as defined in Figure 5. These could be described as follows;

Summer Isles / Horse Island
Eilean Dubh (extended from approach 1)
Loch Broom
Little Loch Broom and Gruinard Bay (as per approach 1)
Loch Ewe

The benefits

The spatial measures would deliver sufficient protection for all habitats, in combination with the capacity restriction. This would further the conservation objectives for all features from a fisheries perspective.

The costs

Method

Average annual MPA value

Average annual value affected

% of value affected

Average annual effort hours in MPA

Average annual effort hours affected

% of effort affected

Trawl

£313

£39

12.5%

4482

472

11%

Dredge

£39

£16

40%

454

164

36%

Table Q3: Average annual impact of approach 2 based on 2007 to 2013 data for over 15 metre vessels (rounded to nearest £000s)

Wester Ross covers part of ICES rectangles 44E4 and 44E5. According to the analysis of Scotmap data for trawl fisheries approximately 27% of the total value of those ICES Rectangles is taken from the MPA. Amount affected is based upon the effort proportion affected for trawling (11%) by over 15 metre vessels.

Method

Total effort days

Effort days affected

Total value

Value effected

Trawl

230

25

£283

£31

Table Q4: Average annual impact of approach 2 based on 2013 data for under 15 metre vessels (rounded to nearest £000s)

The displacement effects

The area around the Summer Isles is where most of the displacement would occur. There are other grounds within the MPA (which do not have protected features) which would be available to these vessels as shown in figure Q7. In overall terms it does not represent a significant amount of effort.

Vessels over 150 GRT are more than capable of fishing on grounds outwith the MPA. There are significant areas of burrowed mud on the North Minch for these vessels to operate on, and consequently any displacement effect would be widely dispersed (see figure Q9). The extended area from Eilean Dubh takes in some of the burrowed mud habitat in the outer part of the MPA but it appears to have a low level of fishing effort when compared to adjacent areas (See figure Q5). The measures also avoid the most valuable grounds to the under 15m nephrops trawl fleet according to Scotmap data, as shown in figure Q6.

Therefore there is unlikely to be any significant negative environmental effect.


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