The topic of fisheries in the Black Sea contains a bewildering array of statistics that are often either incomplete or incomparable. The exploitation of marine living resources, in particular fisheries, represents an important economic sector, but also has a substantial social impact for local communities throughout the Black Sea region. Perhaps more to the point, the issue of fisheries management seems to be a politically charged issue at national levels throughout the world, with negotiated international agreements taking many years to come to fruition and the emerging compromises often offering considerably reduced protection of these valuable resources.

However, the problem of changıng commercial marine living resources (MLR) is not simply one of resource fluctuatıons, together with theır associated socio-economic consequences. There are huge implications for marine ecology, biodiversity and the ability of the Sea to process the nutrient/pollutant loads which it receives. As will be shown later, total catch statistics by themselves reveal very little about the sustainability of existing practices/resources.

Major changes continue to occur in the underlying contribution of different species to overall “total catch” estimates, meaning that total catch statistics, reflecting human responses to the changing resource, hide an underlying problem. For example, since the early-mid 1990s, total fish catches have increased in the Black Sea, intimating that the resource has recovered during the last decade, but this is largely due to increased catches of anchovy and sprat. Catches of whiting (ımportant for the maintenance of turbot and spıny dogfish communities) and horse mackerel have declined over the same period (Fig. 4.6). Mullet catches have also fallen dramatically since 1966, but there are some positive signs: in Romanian waters at least, red and grey mullet populations appear to be undergoing some recovery, as do bluefish and horse mackerel populations. Horse mackerel and shad have recently re-appeared in Georgian waters and during the last decade indicators suggest that turbot stocks may have begun to recover in Bulgarian waters.

However, Romanian turbot catches have remained depressed and Turkish turbot catches have been very low since 2002, with only 119 tonnes landed from the Black Sea during 2003, compared to landings of about 2,000 tonnes during the mid-1990s. Likewise, Turkish spiny dogfish and whiting catches (demersal species, as is turbot) have progressively dwindled. Sturgeon, sea trout, corb and brown meagre catches are also severely depressed.

Figure 4.6      Trends in Black Sea fish catches, 1990-2004

Of those fish taxa found in the Sea, the following represent the major catches in terms of weight:

• Anchovies (Black Sea and Azov Sea anchovy)
• Horse mackerel
• Whiting
• Bonito
• Bluefish
• Sprat
• Mullets (red, thick lip grey, golden grey, thin-lipped, leaping grey, common grey, Pacific/haarder and striped red mullet)
• Spiny dogfish
• Turbot
• Shads (Caspian, Danube, pontic, common, twaite and pontic shad).

However, other fish, notably sturgeons (Russian, spiny, starred and common sturgeon, and sterlet) and beluga (also known as great sturgeon), are of great economic importance. Furthermore, mussels and Rapana, the Japanese snail, represent the most important invertebrates from a commercial viewpoint.

The transboundary importance of commercial fish species is supported by both economic and ecological factors. The majority of fish species with commercial value are shared within the Economic Exclusive Zones (EEZs) of many states such as sprat, whiting, dogfish, turbot and others. Migratory species such as anchovy, horse mackerel, bluefish and bonito have spawning, feeding and wintering areas located in the EEZs of different states depending on the time of year and lifecycle. Consequently, the management applied in exploitation of shared and migratory stocks must take into consideration appropriate levels of catches in each coastal state. The distribution of benefits by coastal countries should reflect the territorial distribution of the resources. At present, Turkey is responsible for some 80% of the reported total Black Sea fish catch, but the length of the Turkish coastline is less than one-third of the entire Black Sea coast (Table 3.1)

The scale of the problem depends over what time-scale the issue is judged, and over what geographical areas. For example, some statistics from Ukrainian waters (Table 4.9) suggest that, since the 1960s, the fishery for some species has collapsed almost completely.

Table 4.9    Average annual Ukrainian Black Sea catches of selected fish (tonne), 1950-2004

However, such statistics take no account of fishing effort or changes in fishing practices. For example, record catches of bonito were achieved by the Bulgarian and Turkish fishing fleets in 2005 (Fig. 4.7). This highlight an additional problem: if numbers of depressed economically important species do begin to recover, there is a tendancyto over-target these, with the results that stocks either do not recover, or recover only very slowly. However, this presents a paradox: on the one hand a reason given for the non-recovery of some commercially important fish species is that insufficient funding is available for boat owners to change fishing gear and practices to cope with changes in policy. However, for high value species, the industry appears able to find funding.

Figure 4.7      Annual Turkish Black Sea catches of bonito, 1989-2005

Fig. 4.8 provides an illustration of how active fishing practices (trawling, etc.) have rapidly replaced passive fishing practices (long lines, pound nets, gill nets and trammel lines) in the Romanian coastal fishery. This change in the relative importance of active vs. passive fishing techniques is due to to a change in pelagic fish behaviour, believed to result from an increased pollution status of shallow Romanian coastal waters and changes in flow regimes due to coastal development. This has resulted. İn shoals moving further offshore to deeper waters, where only active fishing techniques are employed. In addition, the costs of some passive fishing gears, e.g. pound nets have increased disproportionately, thereby reducing their popularity. Thus catch statistics by themselves are of little use in assessing the status of the fishery (see Section 4.3.4).

Figure 4.8      Fish catches in Romanian coastal waters by active and passive techniques expressed as a proportion of the total fishery catch, 1990-2004

While the emphasis of this document is on showing changes that have occurred over the last decade, since the original 1996 Black Sea TDA was written, it is necessary not to lose sight of changes over the longer-term. This is especially important because the agreed long-term target (the EcoQO) of the 1996 SAP was “to take measures… to permit Black Sea ecosystems to recover to conditions similar to those observed in the 1960s.”

The recent collapse of the fisheries is directly connected with the degradation of water and sediment quality, destruction of important spawning grounds, and the outbreak of opportunistic and invasive species. In addition to these, fishing activities are also responsible for the decline in commercial fisheries, as the declining ecological condition is exacerbated by open access to resources, individual countries establishing uncoordinated management regimes, overfishing and illegal fishing in combination with non-sustainable technologies.

• Annual losses of catch value (each hundred thousand tons represents more than 150 million USD).
• Additional expenses for replacement of processing capacities (fish meal production plants, canning facilities, etc.) for adapting at new raw materials.
• Additional expenses for restructuring of (existing) fishing fleet capacities, due to adapting vessels to target new species.
• Losses of employment and income for local communities.
• Increased fragility of the Black Sea ecosystem from anthropogenic pressures which directly impact the status of commercial marine living resources.

The information in Table 4.10 is incomplete, but shows that seafood consumption has varied dramatically since the economic crisis and collapse of the Soviet Union at the end of the 1980s, and is once again increasing. However, demand far exceeds supply from the Black Sea, so huge volumes of seafood continue to be imported.

Nevertheless, the situation does give reason for optimism, since in some countries at least this has led to an increase in commercial marine and freshwater aquaculture, thereby providing increased employment opportunities. For example, Table 4.11 shows that in Ukraine the number of marine and freshwater fish (Odessa Region) and shellfish (Black Sea and Kerch Strait) farms has increased strongly over the last decade, as has the productivity of these farms. Because of the relatively low salinity of the Black Sea, some farmed freshwater fish can also be found in the Sea. For example, sılver carp, Hypophthalmichthys molitrix, whose production in freshwater farms increased over 5-fold between 2004 and 2005, is recognised as an invasive species in the Sea itself.

Of course, poor aquacultual practices, as with any kind of farming, can be a cause of serious environmental problems in their own right. It is, therefore, encouraging that robust scientific/ environmental principles have been developed for Bulgarian mussel farms (Konsulova et al, 2006), particularly in light of the Turkish Eastern Black Sea shellfish industry collapse (Mediterranean mussels, Mytilus galloprovincialis and clams) as a result of Rapana venosa. Considering the very under-developed status of mariculture in Bulgaria, these principles/guidelines have been developed at just the right time!

While sounding disastrous, the Rapana story is an example of how humans have themselves adapted to the changing ecology of the Black Sea. For example, while Mytilus has not been collected commercially along the Eastern Turkey Black Sea coast since 2000, landings of Rapana from the same waters have increased dramatically since then – from a yield of 2-3,000 tonnes/yr during the 1990s to a peak of 12,890 tonnes in 2004 (Table 4.12). From the whole Turkish Black Sea coast, landings of Mytilus plummeted to a mere 17 tonnes in 2001, but have since rallied to values approaching 3,000 tonnes/yr; and in one year (2003), even exceeded 4,000 tonnes. These values are higher than those recorded during the late 1990s (Table 4.12), but still considerably lower than those produced during the 1992-1995 period (approx. 6,000 tonnes/year). Clam production from Turkish Coastal waters has resumed to levels similar to those recorded in the early-mid 1990s (excluding the extremely high 1994 value; Table 4.12)

Table 4.10     Fish production, consumption and employment statistics for Black Sea coastal countries

* Turkey contains about 100,000 licensed fishermen (freshwater and marine) nationwide.

While sounding disastrous, the Rapana story is an example of how humans have themselves adapted to the changing ecology of the Black Sea. For example, while Mytilus has not been collected commercially along the Eastern Turkey Black Sea coast since 2000, landings of Rapana from the same waters have increased dramatically since then – from a yield of 2-3,000 tonnes/yr during the 1990s to a peak of 12,890 tonnes in 2004 (Table 4.12). From the whole Turkish Black Sea coast, landings of Mytilus plummeted to a mere 17 tonnes in 2001, but have since rallied to values approaching 3,000 tonnes/yr, and in one year (2003), even exceeded 4,000 tonnes. These values are higher than those recorded during the late 1990s (Table 4.12), but still considerably lower than those produced during the 1992-1995 period (approx. 6,000 tonnes/year). Clam production from Turkish Coastal waters has resumed to levels similar to those recorded in the early-mid 1990s (excluding the extremely high 1994 value; Table 4.12)

Table 4.11  Aquacultural production in the Ukrainian Black Sea region for commercial fish farms and mussel farms, 1996-2005 (tonnes)

The decline of commercial fish stocks is closely linked with other transboundary problems. It impacts and is impacted by the other transboundary problems and in some cases the linkages are in both directions. From the paragraphs below, it is clear that nutrient enrichment/eutrophication (Section 4.2) and chemical pollution (Section 4.4) are immediate causes of changes in commercial marine living resources, as is habitat change (Section 4.5). In addition marine living resources are a component of biodiversity (Section 4.5)

Nutrient enrichment/eutrophication

Habitats

Biodiversity

Chemical pollution

Nutrient over-enrichment/eutrophication is covered in further detail in Section 4.2. However, in relation to MLR, the following immediate causes have all been identified as contributing to this problem.

• Point and diffuse sources of effluent from livestock farms
• Diffuse pollution from fertilizers
• Ground/soil water discharges (containing elevated levels of fertilizers) to surface waters
• Discharge of untreated industrial effluents
• Atmospheric emission/deposition of pollutants (principally nitrogen) deposited onto land/ directly into the sea.

Chemical pollution

Habitat changes

Alien species introduction

Fishing activity

The problem of perceived over-fishing deserves special attention, since this has been a particularly important cause of major changes in commercial MLR in the past. The total catch is once again showing an increasing trend, but this still only about half of the level caught in the 1980s. However, selective fishing for rare and high value species, such as dogfish, turbot, etc. is undoubtedly damaging/preventing the recovery of these species, as are by-catches of these species when other species are targeted. Under-reporting of actual catches is also likely to be problem, due to high taxes (in Turkey at least) and the fact that fish markets are unevenly distributed along the coast. This casts doubt on the data presented (e.g. in Figs 4.5 and 4.7). Since fisheries data collection systems (again, in Turkey at least) are not effective and cannot provide the information for robust fisheries management. Fishing fleet over-capacity is a continuing problem in the Black. The trend shown in Fig. 3.21 is therefore a problem, since if fishing vessel operators can only make a meagre income, the tendancy will be for them to spend longer and longer at sea, resulting in unsustainably higher catches. This could help explain the increasing trend in total cath statistics shown in the same figure. Stock assessments have been undertaken by most countries for some fish species and are used by some as the basis of their allowable catches, but not for all fish species, not necessarily for the same fish species and many of such assessments are now out of date. The real problem with determining the extent of over-fishing, however, is the lack of evidence. A number of methods (indicators) are available, of which catch per unit effort and stock assessments are the most widely recognised. Fishing effort needs to be estimated differently for active (trawling) and passive fishing (those where stationary nets are deployed and fish are trapped within them) techniques. Clearly more and larger trawlers/nets will catch more fish if they are operated or deployed for the same length of time, and this fails to account for potential differences in net mesh size. Thus, a wide range of different “unit effort” estimates can be made (e.g. Fig. 4.10), with limited comparability between the values produced by different countries, and often between the shape of CPUE time-series plots using different unit effort criteria.   Figure 4.10    CPUE statistics (total fish catch) for Romanian coastal waters, 1989-2004 For the Black Sea as a whole, the only measure of “unit effort” available is the total number of fishing vessels >12 m in length. However, more than 7,000 Turkish fishing vessels operate in the Black Sea, of which 85 % are under 10 m overall length., in Bulgaria there are are over 800 and in Romania 500 fishing boats of <10m in length. Values taken from Fig.(3.20), indicate an increasing trend in CPUE between 1991 and 2005, suggesting a recovering fishery, but thıs ıs largely due to an ıncrease ın CPUE during the early 1990s when landings were very much lower than in the 1980s. When only data since 1996 are considered, there has been almost no change (Fig. 4.11). Figure 4.11    CPUE statistics (total annual fish catch/vessel >12 m length) for the whole Black Sea, 1991-2005 The reality is that despite the catastrophic decline in fish landings during the late 1980s/early 1990s, in large part due to over-fishing, no better understanding of what constitutes “sustainable” catches (total or for individual species) exists. However, for the now rare species discussed in Section 4.3.1, any targeted fishing should be classed as over-fishing.

River regulation and land management

A number of the identified underlying causes associated with changing marine living resources are concerned with eutrophication. These are discussed in detail in Sections 4.2.4 and 4.2.5, including poor operational guidance and management of both point and diffuse sources of nutrients. This includes a failure to use appropriate technologies for the treatment/disposal of waste from point sources (municipal and industrial) and a failure to effectively manage nutrient inputs to agriculture, with an emphasis on poor recycling of nutrients between the two main agricultural sub-sectors – livestock and arable farming. The expansion of coastal populations, and particularly of seasonal resorts needs particular emphasis, since sewage treatment works and sewerage systems originally planned to serve resident (winter) populations, may end up having to serve the waste generated by three or more times the resident population during the peak summer season.

Illegal shipping/harbour operations, particularly in relation to ballast water treatment (invasive species introduction) and bilge water operations (illegal discharges of oil and other pollutants are also significant underlying causes. At present there is no effective monitoring and intervention plan for pollution from ships, and despite ballast water being highlighted in the 1996 TDA as an important vector of alien species introduction to the Black Sea, little has been done on ballast water treatment. None of the Black Sea States are party to the 2004 International Convention for the Control and Management of Ships’ Ballast Water and Sediments (the BWM Convention).

Unsustainable fishing practices are also identified as an underlying cause. Such practices include a failure to link fish stocks to fishing fleeting landings, resulting in the over-fishing of the 1980s, and the direct destruction of seabed communities and habitats through the use of bottom trawling/dredging gear. The fine particles re-suspended by such practices can be transported by currents over large distances, reducing water transparency and ultimately “smothering” benthic organisms. The same effects have resulted from the inappropriate use of techniques for sand/gravel extraction and disposal of dredging spoil, which have contributed to the disturbance/destruction of benthic communities long distances from where the actual extraction took place or the spoil was deposited.

By-catches of non-target species are a continuing problem in the Black Sea, since the majority of fish caught are of such small size fishes (e.g., anchovy and sprat). Fishing gear targeting these species is therefore unselective, despite the apparent emphasis on minimum sizes of fish which are supposed to be caught (Annex 8). For example, pelagic trawl nets for sprat have a mesh size of 14-15 mm. Pound nets for anchovy and horse mackerel have the same mesh size. The catches of such fishing gear contain an important percentage of juveniles of larger size species, such as sturgeons, bonito, bluefish, spiny dogfish and turbot. Throwing live juveniles back into the water is not a common practice in the Black Sea.

There is limited data for by-catch rates in the Black Sea. Whiting, spiny dogfish, Azov anchovy and turbot may be harvested as by-catches during trawling for sprat. In contrast, the sprat catch may reach up to 60% of the Turkish total catch in February, even though anchovy is the main target. Different fishing methods may all result in relatively high by-catch rates depending upon the season. Of course, it is not only non-target species of fish which are caught in fishing nets; dolphins and porpoises are also caught in the gill nets used for turbot fishing. The main victims of these are harbour porpoises (more then 70% of stranding records), followed by young common and bottelnose dolphins.

Illegal fishing practices (poaching) focus mainly on high value species (sturgeons, turbot, spiny dogfish, etc), thereby increasing pressures on them. These practices tend to have a relatively low effect on total landings statistics, but their impact is magnified on already rare or endangered species. A secondary effect is that fishing gear from poaching activities tends to be abandoned as poachers “cut and run” to escape capture and vessel confiscation. This abandoned gear can continue to trap fish, mammals and birds. For example, during April 2002, a clamp-down by Romanian authorities on illegal fishing activities, resulted in the retrieval of some 40 km of gill nets, which were estimated to have trapped about 100 porpoises and dolphins.

During the last 50 – 60 years, the majority of rivers draining into the Black Sea have been changed, with an irreversible impact on the spawning habitats and behaviour of anadromous/catadromous fish. The building of dams and weirs has greatly reduced the breeding areas for fish such as sturgeons, concentrating them at the base of dams and increasing their vulnerability to poaching. Likewise, draining of riparian meadows has led to changes in river flows, currents and losses/blockage of freshwater spawning gravels (by in-filling with finer substrates), with consequent changes in fish behaviour. The latter leads to more rapid changes in flow following rainfall, which are countered to some extent by entrapment of rivers behind dams, but the overall effect is of greater river flow, albeit with reduced seasonality in these flows.

Important changes have also occurred in some countries at the interface between freshwaters and coastal waters provided by lagoons and limans. These are important feeding and breeding habitats for both local or migratory species. The results has been a transformation of these the lagoons/limans into freshwater reservoirs for irrigation or aquacultural reasons; once again, preventing the passage of migratory fish through them and therefore providing a physical blockage, separating the inflowing rivers from the Sea itself.