4. Description of the area


Exploration drilling
in the
Faroe-Shetland Channel

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4.          DESCRIPTION OF THE AREA
4.1          Topography and sediment characterisation
4.2          Hydrography and Meteorology
4.2.1              Current and Water Masses
4.2.2              Wind and Waves
4.2.3              Air Temperature
4.2.4              Visibility
4.2.5              Pollution Status
4.3          Biological Characteristics
4.3.1              Plankton
4.3.2              Fish
4.3.3              Seabirds
4.3.4              Marine Mammals
4.3.5              Benthic Flora and Fauna
4.4          Natural and cultural conservation
4.5          Fisheries
4.5.1              Structure and importance
4.5.2              Demersal fishing
4.5.3              Pelagic fishing
4.5.4              Fisheries regulations
4.5.5              Aquaculture
4.6          Recreation and amenity use

 

 

4.      DESCRIPTION OF THE AREA

A description of the environmental conditions in the area forms a vital part of the impact assessment and risk analyses. However, focus must be placed on the key characteristics relevant for indication of potential impact, and in this respect, the temporal and spatial distribution as well as the abundance of the environmental priority issues are emphasised. Supplemental information on oceanographic characteristics is a pre-requisite to obtain the required transparency to the reader; such data are the physical basis for the natural resources and the marine ecosystem. Thus, this section highlights the results of the project phase of the EIA; for more extensive details, reference is made to the cited baseline reports.

4.1      Topography and sediment characterisation

The Faroe-Shetland Channel is a narrow deep-water trough lying between the west Scottish continental shelf and the Faroe Island plateau. The trough narrows southward from about 190 km width at 62° 30' N to 90 km width at 60 °N. To the north, the Faroe-Shetland Channel opens into the Norwegian Basin at depths of 1,500-2,000 m, while it is connected to the Atlantic ocean via the Faroe Bank Channel to the southwest. To the south, the Wyville-Thomson Ridge separates the Faroe-Shetland Channel and Faroe Bank Channel from the Rockall Trough. Along the northwest slope of the Faroe-Shetland Channel lies the Fugloy Ridge, a west-southwest–east-northeast elongated continuation of the Faroe platform.

Figure 4.1. Perspective map showing the bathymetry of the licence area and surroundings.

The seabed geology around the Faroe Islands is characterised by basalt outcropping in shallow-water areas near the islands and on the banks to the west of the islands. Below about 200 m depth, the seabed is characterised by Quaternary and Holocene sediments of various origin and grain size. In general, the environment can be divided in the following three major regions (cf. Figure 4.2):

Ø      Shelf Region, water depths less than 300. Basalt outcrops occur mainly at depths less then 200 m in the inner parts of the shelf around the Faroe Islands and on the apex of the Wyville-Thomson Ridge. More generally, a thin layer of seabed sediments, up to a few metres thick, is found in the shelf region. The outer part of the shelf is characterised by glacial sediments.

Ø      Slope Region, water depths between 300 and 900 m. The seabed sediments in this region generally consist of soft, silty clay with varying amounts of sand, clasts and shell fragments.

Ø      Channel region, water depths greater than 900 m. Seabed sediments in the Faroe Bank Channel and Faroe-Shetland Channel show evidence of significant deep-water currents. The dominant material in this region may be silty sand with significant occurrence of gravel, cobbles and boulders at the sediment surface in some areas 

<
Figure 4.2. Distribution of sediment types in the area around the Faroe Islands. Source: Bett et al. (2001).

According to the expert review of the seabed (Bett et al. 2001), the sediment grain size tends to decrease with depth. It also appears to be a systematic variation in sediment type from north to south, with coarser/lower mud content sediments to the south. This variation is presumably related to the narrowing of the channel to the south, with corresponding increase in current speeds, and so may also be evident on the western flank of the channel (East Faroe Slope).

In the southeast corner of the review area, analysis of available 3-D seismic data indicates the presence of active, giant sand waves. These and other features related to high current action may well be frequently encountered at the narrowest point of the Faroe-Shetland Channel and on the Faroe side of the Faroe Bank Channel. In this area the occurrence of lag sediments with outcrops of older sediments below reflects an erosional environment in the deep channel. Of particular note is a very large crescentric/scalloped scarp running perpendicular to the channel axis. This scarp appears to exert a significant effect on the downstream surface sediment facies introducing considerable environmental heterogeneity to this area [1] .

4.2      Hydrography and Meteorology

This section forms a brief review of selected key hydrographical and meteorological characteristics of the southern Faroese waters. Emphasis is placed on the characteristics considered of importance to the ecological conditions in the area, and consequently of relevance to the assessments of likely impact and analysis of environmental risk in Section 5.

4.2.1   Current and Water Masses

The water masses of the Faroe-Shetland Channel consist of an upper layer of warm North Atlantic Water flowing towards the northeast into the Norwegian Sea, overlying a lower layer of cold Norwegian Sea bottom water, flowing in the opposite direction (Turrell et al. 1999). The colder, deeper layer is funnelled to the west through the Faroe Bank Channel and into the North Atlantic to the west of the Faroe Islands. The boundary between the warm and cold waters is rather dynamic and may occur in depths between 400 and 600 m on the Shetlands side and 500 and 800 m on the Faroe side (Bett et al. 2001).

Water masses

Five separate water masses can be recognised within the FSC on the basis of salinity and temperature (Turrell et al. 1999). These water masses are described in the following paragraphs with regards to the vertical distribution.

Surface layers. In the surface layer two distinctive water masses exist: North Atlantic Water (NAW) and Modified North Atlantic Water (MNAW). The NAW is warmer (> 8 °C) and more saline surface water, which is confined to the Scottish slope and exists inshore at depths less than 400 m. This water is associated with the Slope Current flowing northward from the Rockall Trough along the Scottish shelf edge into the Norwegian Sea.

MNAW (6.5-8 °C) flows clockwise around the Faroe plateau before turning northward in the Faroe-Shetland Channel to flow parallel to but offshore of the NAW. MNAW dominates the surface waters in the channel in terms of areal extent. Typically the surface waters occupy the upper 200-400 m of the water column, and are thickest under the core of the NAW close to the west Shetland shelf edge. NAW consists of two branches of originally the same water mass. One branch flows from the southwest through the channel and one branch turns northwards to the southwest of the Faroes and crosses the Faroe-Iceland Ridge. It then flows clockwise around the Faroe Plateau, arriving in the Faroe-Shetland Channel from the northeast (Hansen & Østerhus 2000). A smaller fraction of this water may escape through the Faroe Bank Channel. MNAW recirculates within the channel to join the warmer and more saline NAW to flow into the Norwegian Sea (Van Aken 1988).

The current speed is low on the Faroese side of the Faroe-Shetland Channel, mostly below 5 cm/s and flowing southwest. The majority is then circulated anti-clockwise and in turn transported northeast with higher speeds. On the Scottish slope the mean flow exceeds 20 cm/s (Hansen et al. 1999; Turrell et al. 1999). The flow of Atlantic water (NAW + MNAW) through the Faroe-Shetland Channel, into the Nordic seas is estimated to be 3.7x106 m3/s (Hansen et al. 2000). In addition about 1.3x106 m3/s enter the Faroe-Shetland Channel to the southeast of the Faroes.

Figure 4.3. Schematic illustration of typical distribution of different water masses on a section between the Faroese and Scottish Plateau. Based on: Debes (2000); Turrell et al. (1999); Hansen et al. (2000).

Intermediate layer. Below the surface layer waters, colder East Icelandic/Arctic Intermediate Water (EI/AIW) arrives from the north on the eastern Faroe Plateau slope and mixes with the modified North Atlantic water.  AIW (2-5.5 °C) flows anticlockwise along the southern edge of the Norwegian Sea Basin and around the Faroe-Shetland Channel. It occupies a band across the channel, lying at a depth of 300-600 m on the western side of the channel, beneath the MNAW. The water flows in southern and southwestern direction, and is then occupied by the MNAW to the south-southeast of the Faroes. On the Scottish side of the Faroe-Shetland Channel little of this water occurs (Hansen et al. 2000).

Bottom layers. Due to sinking of surface water in the Arctic Ocean and Nordic seas, an overflow of cold and somewhat less saline water is pushed through the deepest part of the Faroe-Shetland Channel, below about 600 m depth. Two different water masses occur in this part of the Channel. First is the Norwegian Sea Arctic Intermediate water (NSAIW) between ÷0.5 and +0.5 °C and below that is the Norwegian Sea Deep Water (NSDW) colder than ÷0.5 °C (Hansen & Østerhus 2000). The water follows the lowest passage and therefore turns northwards south of the Faroes and is pushed with high speed through the narrow Faroe Bank Channel (Hansen & Kristiansen 1999).

The total flow of this water is estimated at about 1.9x106 m3/s (Østerhus et al. 1999). The current speed is variable, depending on the location in the Faroe-Shetland Channel. As the channel is funnel-shaped the speed increases and culminates in the narrow Faroe Bank Channel where the maximum velocity exceeds 1 m/s (Østerhus et al. 1999; Hansen & Kristiansen 1999).

Figure 4.4. Schematic diagram of surface and deep-water circulation in the Faroe-Shetland Channel. Based on: Turrell et al. (1999); Bett et al. (2001); Debes (2000).
Temperature and salinity

Westerberg (1990) mapped temperature variations throughout much of the Faroe-Shetland Channel. On the West Shetland Slope, a 0 °C isotherm ranging from 400-800 m and a 7 °C isotherm ranging from 300-500 m is indicated. Westerberg also assessed temperature range in terms of temperature variance (standard deviation), indicating maximal variance at depths between 500 and 600 m. It is likely that much of the variation in bottom water temperatures encountered at intermediate depths in the Faroe-Shetland Channel is related to the passage of internal waves.

Based on hydrographical data provided by Fiskirannsóknarstovan, Johansen (2000) has prepared vertical profiles of temperature and salinity from the prospective exploration drilling region (cf. Figure 4.5). These data have been used in the near field oil drift modelling (cf. Section 3.2.5).  

 
Figure 4.5. Temperature (left) and salinity (right) profiles from the prospective exploration drilling region. Thick lines in black, blue and red show representative profiles selected for use in the near filed oil drift simulations (cf. Section 3.2.5). Source: Johansen (2000).

4.2.2   Wind and Waves

Wind

The mean wind speed is generally high in the Faroe Islands, particularly in the autumn and winter. It is normally lowest during summer (4,5-6 m/s) and highest during winter (6,5-10 m/s). April to August are normally without strong winds, i.e. full gale, while autumn and winter are particularly windy with numerous gales, usually blowing from the west and south west. Vigorous development of cyclones are typically an autumn and winter phenomenon, sometimes with wind speeds of more than 40 m/s and gusts above 70 m/s. Though the general climate is very windy, calm periods do occur, most often in midsummer, but then only for very short periods. Wind speed statistics for three different locations are shown in Figure 4.6 and 4.7.

Figure 4.6. Climatological normals - mean wind speed (m/s) per month and on annual basis. Source: Cappelen & Vaarby (1998).

 

 
Figure 4.7. Distribution of wind speed and direction at Mykines lighthouse, Akraberg lighthouse and Tórshavn. Source: Cappelen & Vaarby (1998).

At Mykines lighthouse the wind blows for more than 40% of the time from either the north or southeast. Winds from the northwest rarely occur. As this picture differs markedly from that at the other stations it is assumed that local topography is causing this variation.

Winds from the south west to west occur most often at Akraberg lighthouse. At this southernmost point in the islands the climate is very windy, and the highest mean 10 - minutes wind speed (10.2 m/s) occurs here in December.

Tórshavn shows more or less the same frequency of wind direction as Akraberg lighthouse, but generally the winds are weaker. The percentage of calm wind is higher at Tórshavn than at the other stations.

Waves

The formation of waves is a function of wind speed, duration of the wind and the wind fetch. Wave statistics for a location at 60.3 ºN and 5.4 ºW are shown in Table 4.1 and Figure 4.8.

Table 4.1. Significant wave height - statistics for a location at 60,3 ºN and 5,4 ºW. Data from the Norwegian Meteorological Institute, Bergen.

Station

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Year

0 – 0.5 m

0.1

0.4

0.7

1

1.2

1.2

1.3

1.1

1

0.1

0.1

0.1

0.7

0.5 – 1.5 m

5.2

7.7

6.8

12.3

19.4

24.2

24

21.8

11.5

6

4.5

2.9

12.2

1.5 – 2.5 m

13.4

17.3

16.4

28.4

39.1

42.1

43.6

44.2

32.1

20.9

17.9

12.3

27.4

2.5 – 4.0 m

34.8

33.8

38.3

37.2

30.9

26.8

26.7

27.1

37

40.4

39.8

34.5

33.9

> 4.0 m

46.5

40.8

37.8

21.1

9.4

5.7

4.4

5.8

18.4

32.6

37.7

50.2

25.8

 

Figure 4.8. Relative distribution of significant wave height at a location 60,3 ºN and 5,4 ºW. Data from the Norwegian Meteorological Institute, Bergen.

4.2.3       Air Temperature      

During the period 1961-1990 the annual mean temperature in Tórshavn was approximately 6.5 °C. Mean temperatures were around 3.5 °C in January and February and about 10.5 °C in July and August. The temperature fluctuations are generally small. A maximum of 24 °C is observed at Vága airport, while the temperature sometimes drops below 0 °C during wintertime. Mean temperatures per month and on an annual basis are shown in Table 4.2.

Table 4.2. Climatological normals (1961-1990) - mean temperature per month and on annual basis. Source: Cappelen & Vaarby (1998).

Station

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Year

Mykines lighthouse

3.5

3.5

3.5

4.8

6.2

8.5

9.2

9.6

8.7

7.4

4.6

3.3

6.1

Akraberg lighthouse

3.8

3.9

4.0

4.8

6.6

8.4

9.6

10.0

8.9

7.5

5.1

4.2

6.4

Tórshavn

3.4

3.6

3.8

5.0

7.0

9.1

10.3

10.5

9.1

7.4

4.6

3.7

6.5

4.2.4   Visibility

The oceanic location, combined with the polar front and frequent passages of cyclones, causes an extremely large number of cloudy days, 221 days in Tórshavn. During the period 1961-1990 an average of only 1.9 days per year in Tórshavn could be classified as clear, i.e. with a cloud cover of less than 20%. In the same period the average cloud cover was 81%, the highest being 84% in July and August and the lowest being 79% in April.

The annual number of days with fog in Tórshavn is 40. June, July and August are the foggiest months with an average of more than seven foggy days per month (cf. Table 4.3).

Table 4.3. Climatological normals (1961-1990) - number of days with fog per month and on an annual basis. Source: Cappelen & Vaarby (1998).

Station

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Year

Tórshavn

0.7

0.6

0.8

2.1

5.3

7.1

7.2

7.6

4.2

2.9

0.7

0.2

40

4.2.5   Pollution Status

The Faroe Islands are contained within the OSPAR region I: Arctic Waters, and reference is made to the recently published status report for this region (OSPAR 2000b), as well as the main Quality Status Report 2000 (OSPAR 2000a) and other relevant literature. Focus is placed on the background concentrations of heavy metals and persistent organic contaminants such as polychlorinated biphenyls, polycyclic aromatic hydrocarbons etc.

Heavy metals

For heavy metals, background concentrations are related to the normal chemistry or geochemistry of the area concerned. Metals such as cadmium and mercury are found in higher concentrations in areas around Greenland and Iceland than in other parts of the OSPAR Convention area. These levels are explained by natural factors such as sediments of different geological origin and different physical/ chemical conditions.

In Arctic waters, cadmium concentrations of 8 ng/l have been measured in surface waters, while at greater depths, concentrations ranged from 13 – 21 ng/l. Cadmium concentrations  are generally low in the surface sediments, depending of the content of fine grained material. Concentrations in blue mussels are generally lower in Faroese and Norwegian waters (range 0.12–0.35 mg/kg ww) than in Greenland waters (range 0.56–1.25 mg/kg ww). Liver concentrations of cadmium in fish can be high in deep-water fish with a long-life span. Concentrations up to 93 mg/kg ww were found in the kidneys of pilot whales from the Faroe Islands. Recommended limit for cadmium in food for human consumption is 0.3–0.5 mg/kg ww (OSPAR 2000b)

There is little information on mercury concentrations in seawater in the Arctic waters area. Total dissolved mercury concentrations in unpolluted ocean water are within the range 0.2 – 1 ng/l, with higher concentrations in coastal waters. Mercury levels in blue mussels vary little between the different areas, with most values reported between 0.01 and 0.02 mg/kg ww. In mammals, the highest concentrations are usually found in liver tissue, followed by kidney and muscle. Mercury levels in the muscle tissue of pilot whales ranged from 0.9 to 2.7 mg/kg ww (Dam & Bloch 2000), which is high relative to standards set for human consumption (0.3–0.5 mg/kg ww).

In these waters, lead is considered to be of less toxicological importance than cadmium and mercury. Lead concentrations of 15 ng/l in oceanic surface waters, and 3 to 4 ng/l at 1,500 – 2000 meters depth have been reported. Lead levels in fish from OSPAR Region I are generally low. Reported levels in blue mussel range from 0.1–0.48 mg/kg ww.

In Iceland and in the Faroe Islands, copper levels reflect the natural levels in rock of volcanic origin and is not considered to be an element of concern for the marine environment in this region.

Table 4.4. Ranges in background/reference concentrations of heavy metals within the OSPAR area. Source: OSPAR (2000a, b).

 

Sediment

(metal/Al ratio)

Sea water

(ng/l)

Blue mussel

(mg/kg ww)

Cadmium

0.007 – 0.4

5 – 25

0.07 – 0.11

Mercury

0.0034 – 0.0066

0.1 – 0.5

0.005 – 0.01

Lead

1.8 – 4

5 – 20

0.01 – 0.19

Copper

2.2 – 5.7

50 - 360

0.76 – 1.1

 

Persistent Organic Contaminants

In the case of synthetic substances such as many of the persistent organic contaminants, there is no natural concentration, which implies that the natural background level should in principle be zero. However, due to their ubiquitous presence in marine environment, background concentrations are also identified for some of these compounds.

Breakdown of Tributyltin (TBT) in sediments are much slower than in water, and sediments are thus an important environmental compartment and sink for TBT. Imposex [2] characteristics have been found in mussels and snails from the coasts of Norway, Iceland, the Faroe Islands and Svalbard. Concentrations of TBT in affected populations range from 50 to 2,676 mg/kg dw, while unaffected populations from northern Norway had levels of less than the detection limit (17 mg/kg dw).

Polychlorinated biphenyls (PCB) are hydrophobic compounds; i.e. they have extremely low water solubility. Concentrations in ocean water are generally very low and reliable quantification is difficult. Concentration levels of PCB in blue mussel in coastal waters range from 0.5 – 1.4 µg/kg ww. Average concentrations in Atlantic cod range from 63 mg/kg ww in the Faroe Islands to 392 mg/kg ww off the coast of Norway in the Barents Sea. Mean concentrations of sum PCB in pilot whale blubber from the Faroe Islands were 11.9 mg/kg ww (Dam & Bloch 2000).

Anthropogenic activities are generally adapted as the most important source of Polycyclic aromatic hydrocarbons (PAH) released into the environment. Sediments are the most important reservoir of PAHs in the marine environment. Generally the levels in the open ocean are in the low ng/l range. Only limited information is available on PAHs in marine biota from OSPAR Region I. The results indicate levels similar to those thought to reflect global background conditions. A few blue mussel samples from northern Norway contained concentrations in the range of 18 to 76 mg/kg ww.

Other persistent organic compounds. Within OSPAR Region I the lowest levels of HCB, HCHs, DDTs and chlordanes in liver of cod were found from different stocks in Icelandic and Faroese waters. Reported levels were in the range of 1-153 mg/kg ww HCHs and 12-118 mg/kg ww DDTs.

Table 4.5. Ranges in background/reference concentrations (mg/kg dw) of PAHs in surface water in selected regions of the OSPAR area.

 

Northern North-Sea / Skagerrak

Central and southern North Sea

Arctic Ocean / Iceland Sea

Benzo[a]pyrene

8.8 – 112

< 0.2 – 51

1.0 – 3.8

Fluoranthene

14 – 160

0.72 – 97

1.5 – 7.5

Benzo[b+k] fluoranthene

46 – 434

1.1 - 142

7.4 – 30

Pyrene

11 - 128

0.6 - 78

0.76 – 1.1

 

Baseline study

A study to establish baseline levels of chemical components in sediment and fish from the Faroese waters has been performed by RF-Rogaland Research (Grøsvik et al. 2000). Greenland halibut was chosen as the monitoring species. The results demonstrated low levels of metals and not detectable levels of total hydrocarbon or single compounds of PAH. All data supported the characterization of the sediment to be uncontaminated. Levels of metal in fish liver were found to be generally low. No detectable levels of single components of PAH in fish muscle were found.

4.3      Biological Characteristics

This section forms an outline of the focal environmental issues selected during the screening and scoping phase of the EIA (GEMS 2000a, cf. Table 4.6), and include description of the biological characteristics considered relevant for the assessment of likely impact and analysis of environmental risk of the activity described in Section 3. Emphasis is placed on the temporal and spatial distribution and abundance of the resources, i.e. factors considered of vital importance to the species and population vulnerability.

Table 4.6. The environmental focal issues selected during the screening and scoping phase of the EIA. Source: GEMS EIA Programme (GEMS 2000a). In the following sections, the issues are described with regard to relevant characteristics for the assessment of likely impact and analysis of environmental risk (cf. Section 5); i.e. primarily temporal and spatial distribution and abundance.

Selected Environmental Focal Issues

Plankton

Fish

Seabirds

Marine mammals

Shallow water habitats

Deep water habitats

Society

Fishery

Recreation and tourism

Climate / terrestrial

4.3.1        Plankton

Plankton forms a crucial part of the marine food web. Two main groups are recognised, the primary producers, i.e. the phytoplankton, and the primary consumers, i.e. the zooplankton. The zooplankton is in turn important food for fish and fish larvae as well as whales. Both groups are incapable of swimming against currents and are usually transported passively with the water flow.

The oceanographic conditions described in Section 4.2 provide quite different environmental conditions for the plankton on the shelf compared to the outer areas. Inside the tidal front, the water column is relatively homogenous throughout the summer and the plankton at the shelf is relatively isolated from the outer area. In the open sea, a thermocline provides stratification of the water column during summer, forming a prerequisite for the plankton bloom. Thus, the shelf area has its own plankton ecosystem, separated from the surrounding waters (Gaard 1996a). As shown in Table 4.7, the primary production starts earlier inside the front in spring and also declines earlier in autumn than outside the front. 

Table 4.7. The rise and the fall of the plankton communities in Faroese waters. Derived from: Gaard (1996a, b); FRS (1999); Debes (2000). Please note that the dominating zooplankton species, C. finmarchicus descends to the deeper part of the Faroe-Shetland Channel for hibernation (diapause).

Plankton group and area

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sept

Oct

Nov

Dec

Phytoplankton shelf

 

 

 

 

 

 

 

 

 

 

 

 

Zooplankton shelf

 

 

 

 

 

 

 

 

 

 

 

 

Phytoplankton open sea

 

 

 

 

 

 

 

 

 

 

 

 

Zooplankton open sea

 

 

 

 

 

 

 

 

 

 

 

 

 

Phytoplankton

The primary production occurs almost entirely in the summer period; about 80% of the primary production has shown to be produced within the four-month period from May to August. The total production however, varies from year to year (Gaard 1996a; Debes 2000).

The phytoplankton spring bloom on the shelf develops in late April-early May, about one month earlier than outside the tidal front. During spring and summer the biomass tend to be significantly higher in the Faroe Shelf water and in the frontal region than outside the front. Decline of the primary production has been observed from mid July because of nutrient limitations (Gaard 1996a).

A pre-requisite for the plankton bloom in the Faroe-Shetland Channel, the summer thermocline, is usually established early May between 20 and 50 m depth. During late June, the nutrient level decreases and a corresponding decrease in primary production becomes evident. In the Faroe-Shetland Channel the mixing of the water column is more likely, and some peaks in production may be apparent in late autumn.

The growth of the phytoplankton is characterised by successional patterns (Gaard 1996a; Debes 2000). The strong turbulence on the Faroe shelf favour diatoms and such species dominate in the early phase of the spring bloom. In later phases, the larger diatoms tend to be outcompeted by smaller diatoms, flagellates and the colony-forming Phaeocystis (Prymnesiophyta).

The succession pattern is less pronounced in the waters of the Faroe-Shetland channel. The abundance of oceanic species, such as coccolithophorids, may be temporally significant (Debes 2000).

Zooplankton

In general, the peak of the zooplankton growth corresponds to the phytoplankton bloom, but is slightly displaced in time. The biomass however, varies from year to year (Gaard 1996b). A key characteristic of most zooplankton species is the diurnal vertical migration pattern; the day is spent in the deeper part of the water column, while the night is spent in the upper layers grazing on the phytoplankton.

The zooplankton of the Faroese waters is dominated by the copepod Calanus finmarchicus (Gaard 1996b). This species is widely distributed all over the northeast Atlantic and adjacent waters (Sundby 2000, cf. Figure 4.9). However, the annual abundance in the North Sea has declined steadily since the late 1950s (FRS 1999).

Figure 4.9. Spatial distribution of the Calanus finmarchicus and the annual mean temperature at 100 m depth in the North Atlantic. Source: Sundby (2000).

In the Faroese waters, typical trends of the life cycle are recognised. The summer is spent in the upper layers of the water column. During winter, large quantities are advected with the overflow water through the deep part of the Faroe-Shetland and Faroe Bank channels (> 500 m). In spring they ascend towards the surface, and in May, most of the population is confined to the upper 100-150 m layers (Debes 2000). At that time the female produces a small number of eggs. The main reproductive output from the wintering stock is triggered by the spring plankton bloom (FRS 1999).

While ascending from the deep waters, the C. finmarchicus is swept away to the north-east by the predominant currents, and in this respect, the Faroe-Shetland Channel is considered the main region supplying copepods to the North Sea during the spring (FRS 1999; Debes 2000).

Most years the zooplankton on the shelf is quite different from that in the surrounding area. The species diversity is higher and includes several neritic species and meroplanktonic larvae. However, significant numbers of C. finmarchicus may be advected into the Faroe shelf during the spring and summer, and such pattern affects the shelf ecosystem significantly. (The western shelf is considered the main inflow, and the Faroe Plateau cod seems to have a spawning strategy directly related to the inflow pattern.) Studies in the early 1990s have shown that the abundance of C. finmarchicus may be much higher on the Faroe Plateau than outside the front in the autumn (Debes 2000).

Larger species such as krill (mainly Meganyctiphanes norvegica and probably Thysanoessa inermis) occur in large quantities all over the northeast Atlantic and the Nordic seas, but their dynamics are less well understood.

4.3.2   Fish

The Faroese waters hold large stocks of several fish species, also including species of vital importance to the Faroese fisheries (cf. Section 4.5). On the basis of habitat, the fish fauna can be divided into demersal species, i.e. species living close to the bottom, and pelagic species, i.e. species living in the water column.

The commercially important fish stocks are surveyed on an annual basis by Fiskirannsóknarstovan. The results are reported to the International Council for Exploration of the Sea (ICES), which is responsible for the overall assessment and scientific advice on sustainable stocks and fishing levels.

Table 4.8. Stock size (tons) of the commercially most important fish species in the Faroese waters in 1999. Source: Fiskirannsóknarstovan.

Demersal species

Pelagic species

Cod (Gadus morhua)

82,000

Blue whiting (Micromesistius poutassou)

5,384,000

Haddock (Mellanogrammus aeglefinus)

110,000

Herring (Clupea harengus)

8,820,000

Saithe (Pollachius virens)

131,000

Mackerel (Scomber scombrus)

5,195,000

For the following species, population estimates in Faroese waters are not available:

Tusk (Brosme brosme)
Ling (Molva molva)
Blue ling (Molva dipterygia)
Redfish (Sebastes sp.)
Greenland halibut (Reinhardtius hippoglosoides)
Monkfish (Lophius piscatorius)
Greater silver smelt (Argentina silus)

Demersal species

The three most important commercial demersal species are cod, haddock and saithe. The cod and haddock populations spend their entire life in Faroese waters. Also the adult saithe of the Faroe plateau are considered a distinct population without any significant communication with other stocks of saithe, e.g. in the waters of Iceland, west of Scotland, and the North Sea.

The cod (Gadus morhua) of the Faroese waters form two separate stocks, one located at the Faroe Plateau and the other at the Faroe Bank (cf. Jákupsstovu 1999; Toftum 1998). One stock spawns from late February to early May in two distinct spawning areas to the north and the west of the islands. The eggs and larvae drift in the anticyclonic circulation of the shelf water. After spawning the stock is dispersed over the entire Plateau at depths down to 350 m. The other stock spawns from March to May in the shallow water of the Bank, and the eggs and larvae drift in the anticyclonic current of this area. The main spawning areas are shown in Figure 4.10.

Figure 4.10. Main spawning areas of cod. Source: Jákupsstovu (1999).
 
Table 4.9. Population trends of cod 1979-1999. Data from Fiskirannsóknarstovan.

The haddock (Mellanogrammus aeglefinus) spawns from March to May at depths between 50 and 200 m. Spawning takes place all over the Faroe Plateau. However, four main spawning areas, to the north, north-west and south-east of the islands, have been identified (cf. Figure 4.11).

Figure 4.11.  Main spawning areas of haddock. Source: Jákupsstovu (1999).
 
Table 4.10. Population trends of haddock 1979-1999. Data from Fiskirannsóknarstovan.
 

The Saithe (Pollachius virens) is widely distributed in the Faroese waters. Spawning takes place at 150-250 m depth east and north of the islands from January to April. The pelagic eggs and larvae drift with the anticyclonic current on the Plateau until May-June, when the juveniles migrate inshore. The subsequent two years are spent in the shallow coastal waters.

Figure 4.12.  Main spawning areas of saithe. After Jákupsstovu (1999).
 
Table 4.11. Population trends of saithe 1979-1999. Data from Fiskirannsóknarstovan.
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Pelagic species

The main species of the pelagic fisheries are the blue whiting, herring and mackerel (Jákupsstovu 1999; Toftum 1998). Except for the local summer-spawning herring, the stocks are widely distributed. The population trends are indicated in table 4.12 to 4.14.

Herring (Clupea harengus). The feeding and wintering areas of the Atlanto-Scandian spring-spawning herring are located in the Norwegian Sea north of the Faroes. The spawning takes place along the Norwegian coast in March. Before the stock collapsed in the late 1960s, however, significant spawning of this stock also took place on the Eastern banks of the Faroe Plateau, e.g. Sandoyar Banki, Nólsoyar Banki and Suðuroyar Banki. The west of Scotland autumn-spawning herring spawns west of Scotland in the autumn.

The Atlanto-Scandian herring is found in northern parts of Faroese waters in late April, May and June, while herring from the west of Scotland autumn-spawning stock in some years reach the southern parts of the Faroe Plateau during their feeding migration west of the British Isles. 

Figure 4.13.  Distribution area and migration routes of herring. After Jákupsstovu (1999).
 
Table 4.12. Population trends 1979-1999. Data from Fiskirannsóknarstovan.

Blue whiting (Micromesistius poutassou). The blue whiting spawns west of the British Isles. Spawning takes place in late winter–early spring. After spawning the stock migrates northwards to feed, enters Faroese waters in about May, and continue a slow migration northwards before it turn south again in the early winter and heads towards the spawning area.

As a result of the seasonal migration pattern significant parts of the stock are periodically found in Faroese waters (Jákupsstovu 1999). The shelf break around the Faroe Plateau forms an important nursery area to the blue whiting, and after spawning, the bulk of the stock passes the Faroese waters in depths of 300-400 m on both sides of the islands.

 
Figure 4.14. Feeding and spawning areas of blue whiting. Source: Jákupsstovu (1999).
 
Table 4.13. Population trends 1979-1999. Data from Fiskirannsóknarstovan.

Mackerel (Scomber scombrus). The mackerel does not spawn in the Faroese waters, but primarily migrates along the eastern slope of the Faroe Plateau and in the Faroe-Shetland channel from the spawning area southwest of Ireland after spawning in February to July (cf. Iversen 2001, Figure 4.15). The mackerel passes Faroese waters again during winter when returning to the spawning area, but is also found and caught in large numbers during the feeding period.

Figure 4.15.  Feeding, nursing and spawning areas of mackerel. Arrows indicate the migration pattern around the Faroe Islands after spawning. Compiled from: Fiskirannsóknarstovan and Iversen (2001).
 
Table 4.14. Population trends 1979-1999. Data from Fiskirannsóknarstovan.

4.3.3   Seabirds

The Faroe Islands are of international importance for a number of bird species. More than 275 bird species have been recorded. The majority of these are rare or irregular visitors, and only about 50 species breed regularly (Grimmett & Jones, 1989; Bloch et al. 1996). Three groups of birds utilise Faroese waters, split by habitat: offshore, inshore and coastal. The offshore group includes fulmars, storm-petrels, shearwaters, gannets, skuas, gulls and auks. These birds breed on the Faroes, but frequently feed far offshore. In winter, they associate less with their nesting sites and range considerable distances in search of food. Inshore birds include divers, shags, seaducks, terns, some gulls and the black guillemot. These birds normally occur within sight of land, but may on occasion use sites further offshore. Although large numbers of some of these birds breed in the Faroes, others occur in the area during the winter or on migration. The coastal bird population is composed of wading birds and waterfowl, although these have small populations in the Faroes due to the scarcity of suitable inter-tidal areas.

The breeding colonies of seabirds on the Faroe Islands hold a large proportion of the Atlantic breeding populations of seabirds. The productive waters around the islands provide important foraging areas for seabirds all year round, and the steep cliffs, grass-covered slopes and boulder screes facing the sea form ideal nesting sites. The location of the most important bird cliffs and colony sites are indicated in Figure 4.16.

 
Figure 4.16. Main bird cliffs and seabird colonies of the Faroe Islands. Adapted from Grimmet & Jones (1989).

Eighteen sites within the Faroe Islands are considered important for their breeding seabird populations; of these, twelve are considered to be seabird colonies only (Grimmett & Jones 1989), while the six other sites are known to support other birds, although only very small populations. Fifteen of these sites support 1% or more of the world’s population of several seabird species and 13 out of the 19 breeding seabird species exceed 1% of the total European populations.

Fulmar, storm petrel and kittiwake numbers exceed 10% of the European total, and Manx shearwater and puffin numbers are just less than 10%. At an international level, European storm petrel numbers are very important; the islands probably hold about 40% of the world population, with one island, Nólsoy, probably containing 17% of the world population, with 100,000 pairs (Durinck et al. 2001). Fulmars and puffins are the most numerous breeders, followed by European storm petrels and kittiwakes (cf. Table 4.15).

Table 4.15. Estimated numbers of breeding seabirds on the Faroes. After Durinck et al. (2001). Sources: Grimmet & Jones (1989); Bloch et al. (1996a); Lloyd et al. (1991); B. Olsen pers. comm.

Species

Faroe Islands population

European population

% of European population

Fulmar

600,000

5,840,000

10.3

Manx shearwater

25,000

306,000

8.2

European storm-petrel

~250,000

< 580,000

About 40%

Leach’s storm-petrel

1,000

60,600

1.7

Gannet

2,000

223,600

0.9

Shag

1,500

125,000

1.2

Arctic skua

900

17,500

5.1

Great skua

450

13,600

3.3

Black-headed gull

250

1,200,000

< 0.1

Common gull

1,000

488,000

0.2

Lesser black-backed gull

9,000

187,000

4.8

Herring gull

1,500

978,000

0.2

Great black-backed gull

1,200

83,100

1.4

Kittiwake

230,000

1,740,000

13.2

Arctic tern

2,000

278,000

0.7

Guillemot

175,000

3,000,000

5.8

Razorbill

4,500

612,000

0.7

Black guillemot

3,500

100,000

3.5

Puffin

550,000

6,890,000

8.0

 

     
   
Figure 4.17. Location and size (numbers of pairs) of breeding colonies for six seabird species in the Faroe Islands. Beware of the variation of legends. Source: Grimmett & Jones 1989; Olsen  pers. comm.; AMG (1997).

The distribution of seabirds can be characterised by significant temporal and spatial variability. Much of the variability however, can be related to the annual cycle of the different species. The annual cycle of seabirds can be divided into 6 stages: wintering; roaming/foraging at sea; migration; breeding; non-breeding; moulting (e.g. Strand et al. 1993). A description of the annual cycle of seabird species at sea was compiled in 1955. For all the 10 species presented, a correlation between the peak of the plankton bloom and the abundance of seabirds at sea is clearly demonstrated (Salomonsen 1955).

During the summer breeding period, the proportion of the different populations change, and the species are present and carry out their breeding cycle in distinct periods (Salomonsen 1955), as indicated in table 4.16. During this period they do not travel far from the breeding colonies, and the concentrations in inshore areas are therefore very high.

Table 4.16. Annual cycle of Faroese seabirds. Increased abundance indicated by darker shading. Source: Salomonsen (1955).

Species

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Fulmar

 

 

 

 

 

 

 

 

 

 

 

 

Gannet

 

 

 

 

 

 

 

 

 

 

 

 

Guillemot

 

 

 

 

 

 

 

 

 

 

 

 

Kittiwake

 

 

 

 

 

 

 

 

 

 

 

 

Manx Shearwater

 

 

 

 

 

 

 

 

 

 

 

 

Lesser Black-backed Gull

 

 

 

 

 

 

 

 

 

 

 

 

Arctic and Great Skuas

 

 

 

 

 

 

 

 

 

 

 

 

Puffin

 

 

 

 

 

 

 

 

 

 

 

 

Arctic Tern

 

 

 

 

 

 

 

 

 

 

 

 

Storm Petrel

 

 

 

 

 

 

 

 

 

 

 

 

The highest concentrations of seabirds in the Faroes are clearly found during the summer/breeding period. In the winter, most Faroese birds migrate away from the islands, to many parts of Europe, particularly Norway, the North Sea and to UK. Migration of seabirds is among others documented in a comprehensive study by Olsen et al. (2000) with the following conclusions:

Guillemots in Faroese waters during the breeding season (March-August) are mainly Faroese (>90%); with only a small proportion of Icelandic and British birds. In the winter, however, the birds are mainly from Iceland and Britain (equal proportions). The British birds are mainly in their first winter. Most Faroese Guillemots overwinters along the western coast of Norway and in the northern North Sea (Olsen 1982; Nettleship & Birkhead 1985).

Puffins in the summer are mainly from Faroes, and about 10% from Iceland. In the winter, the Puffins in Faroese waters are from Norway, corresponding to approx. 10% of the population. A small proportion of British Puffins are in Faroese waters both in summer and winter.

Razorbills in the summer are mainly Faroese, and about 5% from Britain. In the winter the Razorbills are numerous from about 1st October to 20th of January, and these birds come from Iceland. For the winter it is not possible to make sure conclusion about the Faroese Razorbills, but probably some of them remain in Faroese waters while some migrate to Norway and the North Sea.

The seasonal distribution of Guillemots shows a patchy distribution with the highest densities in the breeding period not further away from the colonies than 60 km (Figure 4.18). In late autumn and winter the guillemots had vacated the entire area except for areas around Sandoyarbanki and Suduroyarbanki around the 200 m contours.

     
Figure 4.18. The seasonal distribution and density (birds/km2) of Common Guillemot in Faroese waters.  February to April (left), May to August (middle) and September to January (right).  Source: Durinck et al. (2001).

Puffins arrive to the breeding colonies from mid April and high concentrations are observed near Sandoy and Fugloy and in the area of Sandoyarbanki in waters less than or around 200 m depth (Figure 4.19). In the breeding period the birds are congregated around the islands. Puffins move away from the colonies in late August and many birds disperse over the Iceland-Faeroe Ridge.

     
Figure 4.19. The seasonal distribution and density (birds/km2) of Puffin in Faroese waters. April to May (left), June to August (middle) and December to March (right). Source: Durinck et al. (2001)

Under the Faroe Islands’ game legislation all birds are protected from hunting within the 200 nautical mile fishing limits, except Fulmar, Manx shearwater, Gannet, Shag, Arctic skua, Great skua, Common gull, Lesser black-backed gull, Herring gull, Great black-backed gull, Kittiwake, Guillemot, Razorbill, Puffin, Raven and Carrion Crow. The game legislation also cites 31 areas as protected against shooting, closer than three miles from the coast and due to old traditions all seabird breeding colonies are treated as sanctuaries (Olsen et al. 2000).

 

4.3.4   Marine Mammals

The waters around the Faroe Islands are inhabited by a large number of marine mammal species, in whole or parts of the year (Table 4.17). The marine mammals may be divided in two groups, seals and whales. Among seals, it is only the grey seal (Halichoerus grypus) that currently is breeding in the Faroes and which are found throughout the year. The grey seals are mainly confined to the coastal areas of the Faroes, but the present knowledge about this species is sparse (Bloch et al. 2000). The occurrence of other species is sporadic. Hooded seals (Cystophora cristata) migrate periodically from further north, and are then in fairly high numbers.

Among the whales, there are at least 13 species that regularly inhabit Faroese waters during whole or parts of the year, mainly on their annual feeding migration (Bloch et al. 2000).

Table 4.17.  Marine mammal species regularly observed in Faroese waters. Population estimates from Bloch et al. (2000).

Species

Estimated numbers in Faroese waters

Estimated numbers in Faroese-Icelandic waters

Estimated numbers in the North Atlantic

Long-Finned Pilot whale

Numerous

 

778,000 (eastern part)

Fin whale

7,000

15,000

50,000

Minke whale

10,000 – 15,000

 

200,000

Blue whale

10

 

1,000-2,000

Sei whale

Irregular abundance

13,500

 

Humpback whale

Few

 

10,600

Sperm whale

Pods up to 50 ind.

 

20,000

Northern Bottlenose whale

Some

 

40,000

Killer whale

1,000

5,000

 

White-beaked dolphin

Few

 

30,000 – 80,000 (northeast)

White-sided dolphin

50,000

 

 

Bottlenose dolphin

1,000

 

 

Harbour porpoise

7,500

 

 

 

Bearded seal

Few observations

 

 

Grey seal

2,000

 

 

Harp seal

Low

 

 

Ringed seal

Low / None

 

 

Harbour seal

Low / None

 

 

Atlantic walrus

Low / None

 

 

The most important and abundant whale species in the Faroe area is the long-finned pilot whale (Globicephala melaena) or grind, a medium-sized toothed whale. Pods from the Atlantic population enter Faroese coastal waters, especially in late summer. The species is exploited in a traditional hunt for subsistence purposes. Records of numbers caught date back to 1584 and show that the occurrence in Faroese waters undergoes periodic fluctuations. The hunt has been regulated since 1832 by specific grind regulations. The numbers taken in 1986-1988, which has been regarded as good pilot whale years, have been around 1,600 individuals.

   
Figure 4.20. Observation data for Long-finned pilot whale (left), fin whale (middle) and minke whale (right) in Faroese waters. Source: Bloch et al. (2000).

The fin whale is the most abundant of the large baleen whales in the area. Faroese commercial whaling began in 1894 and targeted this species especially. Fin whales were the most common whale species taken in the whaling period 1894–1984, with at least 7,580 individuals shot. In the period 1894–1979, a total of 2,200 sei whales were shot, making this species the second most common hunted baleen whale. Sei whales seem to pass the area in the same manner as the blue whale with concentrations at the shelf borders, around the banks and over the Faroe-Iceland Ridge.

The minke whale is the smallest and most numerous of the baleen whales, with an estimated population size of about 200,000 in the North Atlantic (Table 4.20). About 10,000-15,000 individuals occur in Faroese waters. This species was never hunted commercially by the Faroese because of its small size, but a few (121 in the period 1960-1977) were shot for domestic human consumption. Otherwise, Norway has hunted more than 1,000 minke whales commercially from the Faroese area in the period 1938-1983. The distribution pattern from the Norwegian catch shows a high occurence between the islands especially in August and with fewer records offshore and only in high summer.

The seasonal occurence of different whale species in Faroese waters is indicated in Table 4.18. Some general conclusions regarding the distribution of whale species are given by Bloch et al. (2000) as follows:

Ø      The greatest number of whales and the greatest variety of whale species in the Faroese region has been observed in a broad belt along the Wyville-Thomson Ridge from Shetland to the Faroe Islands and the Faroe-Iceland Ridge from the Faroe Islands to East Iceland.

Ø      This distribution pattern indicates that the shelf border and the northern side of the ridges are main feeding grounds for whales.

Ø      The whales usually remain in the main feeding areas in large concentrations and for a long period of time.

Table 4.18. General indication of the main periods when the whale species are present in Faroese waters. Adapted from: Bloch et al. (2000). Increased abundance indicated by darker shading.

Species

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Blue whale

 

 

 

 

 

 

 

 

 

 

 

 

Fin whale

 

 

 

 

 

 

 

 

 

 

 

 

Sei whale

 

 

 

 

 

 

 

 

 

 

 

 

Minke whale

 

 

 

 

 

 

 

 

 

 

 

 

Humpback

 

 

 

 

 

 

 

 

 

 

 

 

Sperm whale

 

 

 

 

 

 

 

 

 

 

 

 

Bottlenose whale

 

 

 

 

 

 

 

 

 

 

 

 

Killer whale

 

 

 

 

 

 

 

 

 

 

 

 

Pilot whale

 

 

 

 

 

 

 

 

 

 

 

 

White-banked dolphin

 

 

 

 

 

 

 

 

 

 

 

 

White-sided dolphin

 

 

 

 

 

 

 

 

 

 

 

 

Bottlenose dolphin

 

 

 

 

 

 

 

 

 

 

 

 

Harbour porpoise

 

 

 

 

 

 

 

 

 

 

 

 

4.3.5   Benthic Flora and Fauna

Shallow water habitat

The typical morphology of the Faroese coast forms the basis for a variety of habitats, ranging from heavily exposed to the more sheltered waters in the narrow sounds between the islands and in the fjords. The habitats are dominated by rocky substrate, i.e. cliffs, rock and boulders, only a few isolated soft-bottom habitats, i.e. sand, silt and clay, are located in inner sounds and fjords (Bruntse et al. 1999; Moore et al. 2001, cf. Figure 4.21).

Figure 4.21. Distribution of shallow water soft-bottom habitats. Source: Moore et al. (2001).

The tidal amplitude is generally low -up to 2 m in outer parts of the islands to the west and in some cases absent- and the vertical zonation pattern typical for rocky shore communities are therefore locally less pronounced. The relation between wave exposure and the distribution and abundance of the flora and fauna however, has recently been demonstrated in a large-scale survey of the shallow water habitats (Bruntse et al. 1999).

On the exposed shores, the supralittoral is dominated by lichens, while red alga, barnacles and mussels are common in the littoral zone. At moderately exposed to sheltered sites, the fucoids are found in large numbers. The associated fauna is numerous and highly diverse, with significant contributions of gastropods, mussels and crustaceans (isopods and amphipods).

In the soft-bottom habitats of the fjords and the sounds, polychaetes and bivalves are the dominating species groups both in numbers and diversity.

Laminarians are the dominating alga in the lower littoral and the sublittoral zones almost all along the exposure scale, forming dense forests with a highly diverse inflora and -fauna. A total of 21 algae and 100 invertebrate species have been observed (Bruntse et al. 1999). These habitats are highly productive, and also provide nursery areas for commercial fish species like the saithe.

Deep water habitat

The deep-water seabed communities of the Faroese waters are not known in quantitative details. However, the large scale Marine Benthic Fauna of the Faroe Islands programmes (BIOFAR I 1987-1991 and BIOFAR II 1995-1998) and the Atlantic Frontier Environmental Network (AFEN 1996-1999) have made significant contributions to the understanding of the faunal assemblages and their dynamics. BIOFAR II was focused on shallow waters, while the AFEN surveys were designed as baseline studies for the planned petroleum activities (AFEN 1999; Bett et al. 2000). Some patterns can also be derived from general biological knowledge and physical characteristics (cf. Section 4.1).

A wide variety of sediment types are found in nearshore waters (AFEN 1999; Bruntse et al. 1999; Bruntse & Tendal 2000; Bett et al. 2000). Gravel and stone mixed with sand and fine sand is the most common sediment type around the Faroes from about 300 to 1000 m depth. On the Faroe Plateau, the sediment is predominantly sand, only few and small areas are characterised by muddy substrate. In depressions on the shelf and in deeper water silt and clay become more prominent. There are also areas of outcropping bedrock, particularly in the shallower waters near the coast and in areas with strong current regimes. At large depths (> 1,000 m) extensive areas are covered by silty substrate more or less mixed with fine sand, cf. Section 4.1.

Sandy sediments reflect low sedimentation rates, and in general, the level of organic material is low. The sediments on the shelf are also subjected to resuspension during storms. Consequently, a dominance of filter feeding species and species that are well adapted to periodic physical disturbance are most likely on the shelf. In areas of finer sediments, like the deep-water seabed, the degree of natural disturbance is lower and the organic loading in the seabed correspondingly higher. Both factors indicate a dominance of deposit feeders, which in general are also less well adapted to disturbance. In two larger soft-bottom areas investigated during BIOFAR, south-east and south-west of the Plateau at 300-350 m depth, the fauna was dominated by polychaetes followed by molluscs.

Four outstanding assemblages are denoted in particular in a review of the BIOFAR results made for GEMS by Bruntse & Tendal (2000):

Horse mussel beds. The horse mussel, Modiolus modiolus, is very common in the Faroes and is frequently found in large mussel beds at depth from the lower shore inside the fjords to about 200 m depth on the plateau. Up to 220 mussels per square meter has been observed, and the number of associated species (more than 143 species) counts for a highly productive and diverse community. The horse mussel beds are considered important as foraging area for cod.

”Ostur” – Cheese bottoms. Large sponges are dominating in Faroese shelf and slope areas as well as the banks to the west, and such assemblages can be made up by up to 50 different sponge species. The distribution pattern of ostur shows long narrow zones close to the shelf bank in depths from about 250 to 500 m. The large and slow-growing sponges make significant contributions to the heterogeneity of the habitat, and although the sponge constitutes 90% of the biomass, a very rich fauna (> 242 species) have shown to be associated with the dominant sponge 

Cold water corals. The deep water coral Lophelia pertusa is widely distributed in the North Atlantic and adjacent seas. The BIOFAR results indicate peak abundance at depths between 250 and 450 m, geographically located on the shelf slope. In some areas the species is a colonial bank-forming coral, building structures several hundred meters in diameter and rising several meters above the sea floor. 298 faunal species have been observed associated with this substrate. In the areas west of Shetland and in the Faroe-Shetland channel only small isolated colonies of the coral have been found.

The octocoral Paragorgia arborea is known from several locations in the Faroes, mainly at depths of 260-650 m. The largest structures observed, about 2.5 m, indicate an age of at least 1,500 years.

Queen scallop beds. The queen scallop, Aequipecten opercularis, is common all over the Faroe area, in waters outside the islands at depths of 50-200 m and sporadically in the fjords. Two areas of particular high concentrations are located on the Faroe Plateau, one to the north of the northern islands and the other east of the central islands. Together, these two areas make up a total of 400 km2.

4.4      Natural and cultural conservation

Two areas within the Islands have been designated as areas for protection under the Faroese Act of Parliament No 48, 1970 of Natural conservation, ammended by Act No 64, 1995. According to Section 9 in the Act the area should be preserved ...“in its natural state, protecting plants, animals and geological formations in their original form, especially from all construction, erection of masts, housing or similar, which may be deemed as unattractive, as well as the removal of stones, rocks, beach, sand, clay, plants and animals is prohibited”.

It is believed that the reasoning behind the protection of areas is not only their inherent nature conservation value but also to guard against damage by man’s activities. The two areas protected are “Mølheyggjarnir heima á Sandi” on the island of Sandoy and “Leynar” on the island of Streymoy (Figure 4.22). The Faroe Islands also possess many sites of historical interest. These include monuments and remains from various Ages. Figure 4.22 also shows archaeological sites in the Faroe Islands.

 
Figure 4.22. Archaeological sites in the Faroe Islands (left) and protected areas (right). Source: Moore et al. (2001).

4.5      Fisheries

4.5.1   Structure and importance

The Faroese economy is heavily dependent upon fisheries. Fishing, fish farming and associated processing industry account for almost 95% of all export from the islands. The Faroese fisheries outside Faroese waters obtained within bi- and multilateral agreements account for about half of the total income from all fisheries. In national waters, the Faroese Government has passed legislation that restricts fishing by specific gear-types and areas at certain times of the year. Since 1975 there has been a considerable expansion of the fishing fleet, although this has not resulted in a corresponding increase in catch. The fleet (in 1999) consists of 78 trawlers, 41 long-liners and seiners and 69 wooden liners and trawlers. The newest segment of the fleet is the 6 deep-sea factory trawlers (FAO 1999).

Faroese fisheries traditionally takes place in the immediate area of the Faroe Islands, in middle areas and in distant waters. The introduction of the 200 nautical mile exclusive economic zone (EEZ) in 1977, changed the pattern from dependency primarily on the middle areas to relatively more dependency on the national fishing territory and the near area.

The fisheries may be considered a multi-fleet and multi-species fishery. The long-liners fish mainly cod and haddock; in addition, some long-liners fish in deep water for ling and tusk. Most of the trawlers fish cod, haddock and saithe, while some large trawlers fish in deeper waters for redfish, blue ling and Greenland halibut. Figure 4.23 gives the starting position for gear deployment of different fishing vessels in 1999, indicating where fishing takes place.

Figure 4.23. Starting position for a) 5 long-liners b)1 gill-netting vessel c) 8 deepwater trawlers (>1000 HP) and d) 8 pair trawlers (>1000 HP) in 1999. Source: Fiskirannsóknarstovan.

Fresh or frozen fillets are the most important export item, with sales of DKK 727 million, followed by whole-fish sales at DKK 561 million (FAO 1999). Exports to EU are dominant, at more than 80% of all exports, followed by Norway, USA and Ireland.

4.5.2   Demersal fishing

The demersal fisheries of the Faroes are mainly based on single-boat trawlers, larger pair trawlers, larger long-liners and gill-net vessels (Toftum 1998; Jákupsstovu 1999). In 1977 an EEZ was introduced in the Faroe area. The demersal fishery by foreign nations has since decreased and Faroese vessels now take most of the catches. In 1996, Faroese vessels accounted for more than 95% of the total landings of the most commercially important demersal fish species. The area west of the Faroe Plateau forms a core area for the fishing activity, which takes place almost all year round, but with peaks during spawning periods.

The three most commercially important demersal species fished for in Faroese waters are cod, haddock and saithe and in good years, annual catches for these three species can total 90,000 tonnes.  The overall sustainable demersal fishery is estimated at 120,000 - 150,000 tonnes per year (Reinert, J, pers. comm.).

Table 4.19. Spawning period for the most important demersal species in Faroese waters. Increased significance indicated by darker shading.

Species

Jan

Feb

Mar

Apr

Mai

Jun

Jul

Aug

Sep

Oct

Nov

Des

Cod

 

 

 

 

 

 

 

 

 

 

 

 

Haddock

 

 

 

 

 

 

 

 

 

 

 

 

Saithe

 

 

 

 

 

 

 

 

 

 

 

 

Fishing for the main commercially important demersal species by large trawling vessels, takes place all around the Faroe Islands to depths of 300-600 m all year. However, among the smaller vessels fishing effort is greatest in the spawning areas during the spawning season (Table 4.19) when large numbers of adult fish tend to concentrate over known areas. In particular the area to the north of the Islands is an important spawning area. After spawning, the continental shelf stocks disperse throughout the shelf area, where fishing takes place all year.

Figure 4.24. Faroese landings of important demersal species in Faroese waters 1990-1999. Data from Fiskirannsóknarstovan.

4.5.3   Pelagic fishing

The three principal species targeted by pelagic fisheries are blue whiting, herring and mackerel.  Although none of these species are present to spawn in the waters around the Faroe Islands, they migrate to the area from distant spawning and nursery areas. In general, fishing for pelagic species occurs along migration routes and within known feeding areas and therefore tends to be more seasonal than the demersal fisheries. The location of the main fishing grounds is based on migration patterns.

Foreign catches account for about 80% of the total landings from pelagic fisheries in Faroese waters. The effort follows the distribution pattern of the individual species:

Ø      The blue whiting is caught by pelagic trawl, mainly in the area around the southern tip of the Faroe Plateau. The catches by Faroese, Norwegian and EU vessels are mainly taken in late April through May, while the Russian effort is almost equally spread throughout the year.

Ø      In offshore Faroese waters, herring is almost exclusively caught by purse seine. Most of the Atlanto-Scandian herring is taken in the Norwegian Sea, north of the Faroe Plateau, while the eastern and southern areas seem most important for the fisheries on the Scotland autumn spawning stock. The local, summer-spawning stock of herring is caught by gill nets in the fjords and sounds.

Ø      Mackerel is caught by purse seine and pelagic trawls. There is a peak in the effort corresponding to the migration and feeding period of the mackerel, i.e. June-September. The location of the fishing areas have varied over time.

Figure 4.25. Faroese landings of important pelagic species in Faroese waters 1990-1999. Data from Fiskirannsóknarstovan.

4.5.4   Fisheries regulations

The demersal fishing in the Faroese waters is regulated by a complicated system of licences, area closures, effort allowances and minimum-by-catch restrictions. The fisheries for cod, saithe and haddock are regulated by the number of days, which are allocated to the vessels fishing these species. Large, single-boat trawlers (> 1000 Hp), which only to a small extent target cod, saithe and haddock, are allowed a maximum-by-catch of these species of 7 % by weight.

Generally, no trawling is allowed within twelve nautical miles of the Faroese territorial baseline. However, during summer, 10-15 small trawlers (< 500 Hp) are allowed to fish in specified areas within this limit, mainly targeting lemon sole and plaice. In addition some areas both inside and outside the twelve nautical mile limit are closed for all gear during the main spawning period. Four large areas outside the twelve nautical mile limit are closed throughout the year to all trawl fishery. Spawning areas for cod and saithe are also closed during the main spawning season, and neighbouring areas are closed prior to, and immediately after the spawning season. The Faroe Bank shallower than 200 m is also closed to trawling (ACFM 2000).

In close co-operation with the fishing industry, the Faroese government has developed a new system for catch quota management, the “fishing day per boat” system, based on within fleet category individual transferable quotas in days. The new system entered into force on 1 June 1996. The individual transferable effort quotas apply to 1) the long-liners less than 100 GRT, the jiggers and the single trawlers less than 400 Hp, 2) the pair trawlers and 3) the long-liners greater than 100 GRT. Single trawlers greater that 400 Hp do not have effort limitations. The effort quotas are transferable within gear categories. In addition to the number of days allocated in the law, it is also stated what percentage of total catches of cod, haddock, saithe and redfish each fleet category are allowed to fish.

4.5.5   Aquaculture

Aquaculture has developed in the Faroese since the late 1970s. The dominant species is trout and Atlantic salmon, were production for the latter reached 40,000 tonnes in 2000 (Table 4.20), representing more than 20% of the total export value. Natural conditions with good quality temperate water all year are consequently suitable for mariculture, but are in practice somewhat limited by the few narrow sounds between the islands. During the 1980’s there were over 60 farms in production but this declined to 22 in 1996, although farms increased in size. In later years the number of farms has again increased to about 55 (Figure 4.26). Fish farms are located on most islands.

Table 4.20. Aquaculture production in the Faroe Islands (tonnes). Data from Federation of European Aquaculture Producers (www.feap.org). Please note that the figures for 2000 appear to be estimates. Detailed data for this year have not been available as of March 2001.

Species

1995

1996

1997

1998

1999

2000

Atlantic salmon

10,000

5,950

15,000

25,000

36,981

40,000

Rainbow trout (>1 kg)

452

63

100

1,000

2,169

2,000

Sum

10,452

6,013

15,100

26,000

39,150

42,000

 

<
Figure 4.26. Salmon fish farms and brood stock sites. Source: Moore et al. (2001).

4.6      Recreation and amenity use

The Faroe Islands attract approximately 25,000 tourists per year. The long stretches of coastline are substantially undeveloped and boast an unspoilt natural landscape of the highest quality. The scenery throughout the islands is characterised by dramatic steep cliffs on the west and north coasts and more gently sloping, fjord coasts to the east. The 750 m high cliffs on the north coast of the island of Vidoy are the highest sheer cliffs in Europe. Due to the Islands’ geography, topography and dependence on the sea, all tourists visiting the Islands gain a close appreciation of the coastline.

The main tourist attractions also concentrate upon the sea and coastal environments. Usual outdoor pursuits include visits to the bird cliffs, cliff top walking, horse riding, sea angling, SCUBA diving etc.

There are a number of sand / shingle beaches that are commonly used for recreation, although none are provided with any amenity facilities (Moore et al. 2001).

 
Figure 4.27. Angling sites, campsites, recreation sites (beaches and diving sites) and whale hunting beaches in the Faroe Islands. Source: Moore et al. (2001).

[1] In geological terms, facies mean the composite nature of sedimentary deposits reflecting the conditions and environment of their origin.

[2] In biological terms, imposex is defined as the development of male primary sexual characteristics in female gastropods.