/ 2. Faculty of Food Science and Engineering, Dunărea de Jos University of Galati

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1 ANALYSIS OF QUANTITATIVE AND QUALITATIVE EVOLUTION OF FISHING MAIN FISH SPECIES OF COMMERCIAL VALUE IN THE LAST TWO DECADES, ON ROMANIAN SECTOR OF THE PONTIC BASIN V. MAXIMOV 1, E. PĂTRAŞ 2, L. OPREA 2, T. ZAHARIA 1, G. RADU 1, C. SION (BADALAN) 2 1. National Institute for Marine Research and Developmen Grigore Antipa Constanta maxi@alpha.rmri.ro / vova_maximov@yahoo.com 2. Faculty of Food Science and Engineering, Dunărea de Jos University of Galati lucian.oprea@ugal.ro Abstract: The species composition of capture in the Romanian marine sector partially reflects the composition of ichthyofauna as the ratio of fished species is mainly conditioned by two factors such as the type of fishing gear and the seasonal conditions for growing and mentaining of agglomerations caught.research on the ichtyofauna of the Romanian Black Sea sector, undertaken from 199 to 29, consisted of tracking the spatial distribution of the key species of commercial value in the shallow and offshore zone as well as both qualitative and quantitative composition of the catch and spread of fish aglomerations.during the reported period, pelagic species (i.e. sprat, anchovy, mackerel etc.) represented 82-9 % of the total catches from the agents of commercial fishing. These catches were mainly made by trawler vessels with a share of 7-8 % in the last twenty years. Key-words: Black Sea, capture, fish species AIM AND BACKGROUND Since ancient times, fishing has been a major source of food for mankind, providing occupation and economic benefits to those who practiced it. It was widely recognized that living aquatic resources were a gift of nature for an unlimited abundance. Still, this myth has been destroyed by the ascertainment that these living aquatic resources, although renewable, are not infinite and must be correctly managed and rationalized if we are to maintain their contribution to the nutritional well-being, so as to the economic and social development of a growing world population. Recent years have witnessed severe mutations to fish populations from the Romanian Black Sea sector due to the anthropogenic causes. Most of these causes have constantly manifested but some of them have occurred with less intensity, as follows: -environmental conditions of the coastal areas are still poor as it is reflected by the removal of fish agglomerations from the shore, during the warm period of the year; -development works and hydrotechnical constructions on the Danube maintained their influence on sturgeon and Danube shad reproduction process; -use of inappropriate tools and fishing techniques; -overfishing on wintering aglomerations of anchovy and horse mackerel; -illegal fishing on reproductive agglomerations of skate and shark.

2 EXPERIMENTAL Methodology and techniques used for data collection, verification, processing and analysis, as well as for the assessment of fish stocks, are in accordance with international methodology generally accepted for the Black Sea sector. Quantitative and qualitative component of fish catches has been obtained, periodically, by centralizing data drawn from statistics of the specialized companies and from interviews with fishermen. Likewise, the fishing effort (no. of vessels/no. of seines/no. of trawls/no. of trawl hours/no. of gillnets/no. of fishing days) was obtained from companies data, from information collected by inspectors of the Fisheries and Aquaculture Agency. These data use to correctly assess the exploitable biomass and allowable catches. RESULTS AND DISCUSSIONS Marine fisheries in the Romanian Black Sea coast is done in two ways: active fishing with coastal trawler vessels, type B-41, Baltic TCMN other types, equipped with pelagic trawl and gill nets, operating in the sea at depths exceeding 2 m; stationary fishing practiced along the coastline at the 28 fishery points located between Sulina and Vama Veche, in shallow coastal zone ( m) with fix gear (trap nets, gillnets, longlines and beach seines) and up to 4-6 m with turbot gillnets and longlines. Catch and fishing effort During the fishing period , the level of catches was quite low, ranging around 1,39 t in 26 and 1,94 t in 25, except the period when they performed over 2 tonnes (2,431 t in 21 and 2,116 in 22), and continued descending up to 435 t in 27 and 325 t in 28 (preliminary data)(fig. 1). The level of catches in the last three years the lowest in the last 2 years was due either to a decreasing fishing effort (descendent number of coastal trawlers, fishing nets and hence the number of personnel engaged in fishing) and growing production costs, or to the influence of hydroclimatic conditions on fish populations 1, 2. Active fishing In the eight / ten months of fishing per year, from the period under review, the Romanian coastal trawler vessels accomplished variable catches, determined by different aspects such as: the fishing effort, the hydroclimatic changes, the status of main species stocks, and the supplying and selling system on the fish market. Thus the catches ranged between 3582 t/1997, 353 t/1998 and declining to less than 5 t in the last three years (298 t/27, 324 t/28, 111 t/29). Catches made in 28 by three operational ships, were of 224 t (preliminary data), the lowest in the history of Romanian Black Sea fisheries, being lower by % compared to 27, respectively % compared to 26 (Fig. 1). Catch declining was mainly due to reduction in fishing effort (no. of ships, no. of fishing days, no. of trawl hours)(table 1, Fig. 2). Deployment of active fishing was and still is determined by the distribution of fish agglomerations (especially sprat populations) and the product demand on the market.

3 In recent years, the fishing vessels activate only under firm orders, given the high fuel costs. The only sectors for the fishing activity are Constanta-Corbu and Zatoane- Sulina. Yield level of trawler vessels in 28 was t/vessel, 1.28 t/day,.51 t/trawl and 1.3 t/hour, in the approximately 175 fishing days, 218 trawls, respectively 435 fishing hours 3,4,5,6,7 (Table 1). Stationary Fishing Generally, fishing with fixed gear on the Romanian coast is characterized by the concentration of activity in the first three/four months of the season (April to July), when the main species come closer to the coastal zone for feeding and breeding. Consequently, the level of catch and fishing yield varied from year to year, depending on fishing effort (number of fishing nets and effective days of fishing), changes in hydroclimatic conditions, stocks of the main fishing species and anthropogenic factors. Catches from 21 to 28 varied between 616 t in 22 and 11 t in 28. Poor results obtained in 28 (11 t) were 36. % lower compared to 27 and % lower compared to 26, mainly due to decreased number of seines (from 41 to 21) and to the fact that reproduction of fish avoided to get closer to shallow areas (less than 1 m), where the seines are usually located 3,4,5,6,7 (Fig. 1, 2). In the last three years, 21 to 22 seines net were installed at depths of 3. to 11. m, depending on the characteristics of the fisheries sector, which achieved a total catch of 11,687 kg, during the 131 days of activity, with an average monthly/daily output of 4.81 t/seine and.7 t/day (Table 1). At those 14 points of professional fishery, which registered fisheries, catches and yield level were different depending on different aspects such as: the number of seines, gillnets for turbot, lines and days of activity. The best results were recorded in 2 Mai- Vama Veche, Tatlageac, Costinesti and Cap Midia. At the amateur fishery points (8 points), a number of 14 authorized persons have carried out their fishing work using gillnets for turbot (about 24 pieces), long lines and usual lines and they have made a catch of 6619 kg, with an average yield of 121,34 kg/gillnet. A number of 39 fishermen legitimated at the AGVPS-Constanta have worked alongside them, and using fishing poles (about 8 pieces) have produced a total catch of about 3, kg and an average yield of 3.75 kg /pole. Species composition of catches The main feature of fish catches made in the Romanian marine sector is the presence of a large number of species (over 2), mostly small species (sprat, anchovy, whiting, goby). Noteworthy is the fact that the share of valuable species (turbot, shark, sturgeon, horse mackerel, shad, mullet, blue fish), remains low and keeps going in critical condition, although their stocks seem to have a recovery tendency. During , on the whole Romanian sector and during the entire fishing season, the dominant species caught was mainly sprat (Sprattus sprattus) and Danube shad (Alosa pontica), which appeared alongside traditional species: anchovy (Engraulis encrasicholus), horse mackerel (Trachurus mediterraneus ponticus), turbot (Psetta maxima maeotica), whiting (Merlangius merlangus euxinus), goby (Gobiidae), picked dogfish (Squalus acanthias), mullet (Mugilidae) and other species as well 3,4,5.

4 Active Fishing With the active fishing, the main species to be caught was sprat, which share of the total catch was of 78.2% in 28. Beside sprat there occurred whiting with 4.4% and only sporadically and mullet (2.2%). Although the horse mackerel was present in the Romanian Black Sea sector during the summer months of 28 (trawl survey was made during the research expeditions in August and September), no vessel reported catches. The active fishing with vessels specially equipped for fishing and having turbot gillnets, made an about 33 t of turbot catch (14.1%) 6 (Fig.3). Stationary fishing With the stationary fishing, the presence of more than 27 species of fish was reported. Their amount was variable depending on area and season. Throughout the whole Romanian fishing sector and the entire fishing period, the dominant species caught were the traditional ones: anchovy (14.8%), sprat (12.8%), goby (11.7%), horse mackerel (1, 8%), turbot (7.1%), whiting (9.6%) and silverside (.6%) 6 (Fig. 4). Catches evolution of the main species of commercial interest Sprattus sprattus (sprat) During , the catches of sprat, the predominant species of the annual catch (except 199, 1997 and 1998, when the catch was around 3, tonnes, as follows: t/199, t/1997 and t/1998) were around 2 t/year, varying between 1.35 t/25 and to/1993. In the last five years, sprat catches have fallen sharply to 492 t/26, 28 t /27, 234 tons /28 and less than 1 t /29 3,4,5,6,7 (Fig. 5). Low catches of sprat was due to the reduction of fishing effort (descendent number of seines and coastal trawlers and, implicitly, a reduced personnel engaged in fishing) and growing production costs, or to the influence of hydroclimatic conditions on fish populations. Engraulis encrasicholus (European anchovy) The period under review can be divided into three distinct intervals. Interval no. 1: , when anchovy catches had an upward trend, reaching a peak in 1993/374 t, then declined to 45 t/ Interval no. 2: , with a constant amount of catches as the annual catches obtained were of 15-2 t, except the peak period, with 296 t/22 3,4,5,6,7. The last interval, i.e , is the poorest in the past 3 years, when the annual catches obtained were less than 35 t (11 t/26, 15 t/28, 21 t/29 and 35 t/27)(fig. 6 ). Trachurus mediterraneus ponticus (horse mackerel) Except the year of 199, when the horse mackerel catch was of 165 t, the catches registered for the analyzed period were below 5 t/year, varying from 3 t in 1999 to 48 t in ,4,5,6,7 (Fig.7). The last 1 years of horse catches have exceeded 2 t, with an annual average of about 1 t, mostly from stationary fishing (seines). Psetta maxima maeotica (turbot) In the past years the interest for turbot was very low, but after 21 fishery operators working on the Romanian coast changed their options and interest, giving priority to vessels properly equipped with specific tools and gear for fishing this species. Catches have increased slightly from one year to another, as follows: kg/21, almost

5 4231 kg/24 and 4432 kg in 27 3,4,5,6,7 (Fig. 8). The best fishing period is the period from March to July and November to December, period that coincides with the formation of turbot agglomerations and, consequently, with their coming closer to the coastal area for feeding and breeding. The rest of the year, the turbot being spread on the entire continental platform of the Romanian Black Sea sector 7,8. Gobiidae (goby) Catches of goby, particularly Gobius melanostomus and Gobius batrachocephalus, caught by amateur fishermen, were around 2-75 t/year between and less than 1 t/year between ,6,7 (Fig. 9). These catches are simply estimated, as there are not clear evidence of these species. Merlangius merlangus euxinus (whiting) From 199 to 29, whiting catches were constantly varying between 2.653t/199 and less than 1 tons in the last five years, when interest for this species have decreased, being reported as auxiliary species spilled into the sea (Fig. 1). Whiting high catches are obtained during the years when water temperatures drop significantly, being a cold water species 5,6,7,8. Mullus barbatus ponticus (red mullet) The red mullet is known as a demersal species with high quality meat. It can be caught with the seines only in Agigea-Mangalia sector where the catches amount to about 1 tons per year (146t/1975) and a total of 15 tons, during Except for 24 and 25, when catches of kg/24, respectively 3354 kg/25, were obtained the annual catches have varied between 219 kg in 28 and 45 kg in 26 6,7 (Fig. 11). Squalus acanthias (Picked dogfish) Shark catches were at high rates only in the interval when they ranged between 1-15 t/year (115 t/1975 and 134 t/1985). After 199 interest in the fishery of this species has declined (especially from 1995 to 25, when there were no reports) and hence catches were reduced to below 1 t per year 5,6,7 (Fig. 12). CONCLUSIONS marine fishery in the Romanian Black Sea coast is made in two ways: active fishing with coastal trawler vessels and stationary fishing, practiced along the coast within the 28 fishery points; quantity and quality of annual catches in the Black Sea are primarily dependent on the reserves of the main species (their migrations and the value of the new generation in completing annual stocks), but mostly on the fishing techniques and the intensity of resource exploitation; during the fishing season from 199 to 29, the level of catches was low, t (except the years 199, 1992, 1993, 1997 and 1998 with t annually) and the last three years meant a new decline to 435 t/ 27, 444 t/28 and 331 t / 29; uneven distribution of the main fish species caught along the Romanian coast, both in range of the seines, at depths of 3-11 m and in the activity of trawler vessels, in depths of 2-7 m. Nevertheless, some changes in fish behavior can be noted, such as: retrieval from the coastal zone and stronger dynamism;

6 throughout the whole Romanian sector and along the entire fishing period (March- November), the catches mainly consisted of: sprat (Sprattus sprattus), turbot (Psetta maxima maeotica) horse mackerel (Trachurus mediterraneus ponticus) and Danube shad (Alosa pontica), which appeared alongside traditional species: anchovy (Engraulis encrasicholus), whiting (Merlangius merlangus euxinus), Gobiidae (goby), picked dogfish (Squalus acanthias) and red mullet (Mullus barbatus ponticus); the dominant species with the fixed gear fishery catches are the traditional ones: anchovy ( %), sprat ( %), goby ( %), horse mackerel (-8.5 %), turbot ( %), whiting ( ) and red mullet ( %); whereas with the active tools the relevant domination belongs to sprat - over 8 % (varying between %), whiting with %, and occasionally, turbot (,1-1,7 %), horse mackerel ( %) and anchovy ( %). Acknowledgements The Research was conducted in the framework of the projects POSDRU Efficiency of PhD Students Activity in Doctoral Schools-nr EFFICIENT funded by the European Union and the Romanian Government. The authors thank to the management staff of the projects for their support.

7 REFERENCES 1. MAXIMOV V., NICOLAEV S., STAICU I., RADU G., RADU ELENA, ANTON E., 26 - Contributions à la connaissance des caractéristiques biologiques de certaines espèces de poissons démersaux de la zone marine roumaine de la Mer Noire. Cercetări marine, INCDM Constanţa, 36: ; 2. STAICU I., RADU GH., MAXIMOV V., RADU E., ANTON E., 24 - Etat des populations des principales especes de poissons a valeurs marchande du secteur marin roumain (199-22); INCDM Constanta, Cercetari Marine/Recherches Marines nr. 35, p ISSN: ; 3. RADU E., RADU GH., ANTON E., STAICU I., MAXIMOV V., Evolution des captures de poissons pelagiques dans le secteurs marin roumain pendant la periode 2-24; INCDM Constanta, Cercetari Marine/Recherches Marines nr. 36, p , ISSN: ; 4. STAICU I., RAYKOV, V., MAXIMOV V., RADU GH., RADU E., ANTON E 27 Status and tendencies of evolution of main gregarian fish stocks in the Romanian and Bulgarian marine sectors; Cercetari Marine/Recherches Marines nr. 37, p , (ISSN: ); 5. DASKALOV G, MAXIMOV V, PANAYOTOVA M, RADU GH, RAYKOV V, ZENGIN M, 28 - Review of Stock Assessment and Fisheries Management Advice of Black Sea Stocks in 29 JRC/STECF-UE. 6. MAXIMOV V, RADU GH., ANTON E, ZAHARIA T., Analiza evoluţiei pescuitului şi a caracteristicilor biologice ale principalelor specii de peşti, din zona românească a bazinului pontic, în perioada 2 28, INCDM Constanta, Cercetari Marine/Recherches Marines nr. 39 (sub tipar), ISSN: ; 7. MAXIMOV V, STAICU I., Evolution of demersal fish species catches from the Romanian marine area between 2 and 27; INCDM Constanta, Cercetari Marine / Recherches Marines nr. 38, p , ISSN: ; 8. MAXIMOV V., RAYKOV V.S., YANKOVA M., ZAHARIA T., 29 - Whiting (Merlangius merlangus euxinus) population parameters on the Romanian and Bulgarian littoral between 2 27; Journal of Environmental Protection and Ecology (in press), ISSN ;

8 Table 1-Evolution of catches and fishing effort in fisheries from the Romanian coastal zone from 199 to 29 Year Catch (t) Stationary fishing Active fishing No. No. C. P. U. E Catch no. no. no. no. trul. C. P. U. E seines days t/seine t/day (t) vess day hours t/vess t/day t/hour t/tr ,6, ,8 4,48,83 1, ,7, ,7 1,72,76, ,4, ,6 4,2,8 1, ,3, ,6 2,25,49, ,1, ,9 2,32,51, ,4, ,1 2,33,77 1, ,9, ,2 1,65,4, ,5, ,5 1,66,84, ,3, ,2 3,65,79, ,1, ,8 2,96,66, ,9, ,5 2,93,63, ,58, ,86 2,96,57, ,2, ,29 1,71,51, ,65, ,56 1,58,57, ,73, ,75 1,77,66, ,, ,89 1,81,68, ,52, ,75 1,31,49, ,23, ,33 1,68,59 1, ,81, ,67 1,28,51 1, ,47, , 1,12,85 1,11

9 tons TOTAL CATCH tons stationary fishing tons active fishing tons 4 ACTIVE STATIONARY TOTAL years Fig. 1-Total catch in the Romanian Black Sea, during (t)

10 no vessels trap nets Fig. 2-The evolution of the fishing effort, during

11 tons 1 9 ACTIVE FISHING TOTAL CATCHES tone t t t t t t t t t t whiting 6,9 13,3 2,5 3,8 4,9 6,5 5,8 2,2 4,4 7 sprat 92,7 85,7 96,2 95,7 92,9 89,7 89,8 89,8 78,2 7,4 anchovy,3,2 horse mackerel,3,5 1,3,5,7,9 1,6 1,1,3 mulet,1,4,1,1,2,2,3,1 1,7,2 turbot 1,4 2,2 2,5 4,2 12,1 21 shark,4,6 1,5,8,6 other,1,2,1,1,3,1,3 1,5,5 Fig. 3 -Percentage of the most important fish species for active fishing along the Romanian seaside, during 2 29

12 % STATIONERY FISHING TOTAL CATCHES ,71 tons t t t t t t t t t whiting red mullet turbot mullet goby anchovy shark shad sprat horse mackerel other 2 24,8,2,4,2 7 34,9,9 9,2 22,4 21 9,2,6 2,9,1 5,8 43,9,7 16,6 2,1 18,1 22 7,8,3 2,7,3 7,5 48,2 28,3 1,1 3, ,6,6 5,3,2 1,5 36,8,2 21,6 8,5,7 24 1,6 8,3 4,9,5 15,5 28,2 5,6 19,7 1,8 4,9 25 4,9 1,8 7,16,6 16,5 24,4,88 5,6 27,45,2 1, ,8 1,58 3,6,4 12,4 5,8 2,3 22,32 35,47 1, ,3 1,2 4,5,7 8,9 29,7 1,9 11,9 17,5,3 22,1 28 6,1 1,2 24,8 1,3 2,9 7,8 1,1 22,5 25,6 3,4 3,3 Fig. 4 -Percentage of the most important fish species for stationary fishing along the Romanian seaside, during 2 29

13 tons 35 3 Sprat Sprattus sprattus total catch / ,477 t Sprat Fig. 5 - Sprat (Sprattus sprattus) catches, between 199 and 29 (t)

14 tons 4 35 Anchovy Engraulis encrasicolus total catch ,597 tons Anchovy Fig. 6 - European anchovy (Engraulis encrasicholus) catches, between (t)

15 18 tons Horse mackerel Trachurus mediterraneus ponticus total catch tons Horse mackerel Fig. 7 -Horse mackerel (Trachurus mediterraneus ponticus) catches, between (t)

16 kg Turbot Psetta maxima maeotica total catch kg Turbot Fig. 8 -Turbot (Psetta maxima maeotica) catches, between 199 and 29 (kg)

17 tons Gobiidae total catch tone Gobiidae Fig. 9 -Goby catches, between 199 and 29 (t)

18 tons 3 25 Whiting Merlangius merlangus euxinus total catch ,342 tons Whiting Fig. 1 -Whiting (Merlangius merlangus euxinus) catches, between 199 and 29 (t)

19 tons Red mullet Mullus barbatus ponticus total catch tons Red mulet Fig. 11 -Red mullet (Mullus barbatus ponticus), catches, between 1995 and 29 (t)

20 tons 1 9 Picked dogfish Squalus acanthias total catch tons dogfish Fig. 12 -Picked dogfish (Squalus acanthias) catches, between 25 and 29 (t)