SPAIN(continue)

7. FISH AND FISHERIES

The fish fauna of Spain's inland waters, like that of Portugal, is poorer in both genera and species than in the rest of continental Europe. Some of the most characteristic fishes of Europe, are absent, for example: coregonids, pike, Alburnus spp., Scardinius spp., and European perch (Perca fluviatilis). It is characterized by an abundance of cyprinids such as Barbus and Chondrostoma but not of abundant populations - especially because of fluctuations in river flow and its subsidence in volume during the summer. However, within its confines there is a distinction between the northern regions where cool water temperatures support not only salmonids but a group of cyprinids which differ from those of southern Spain.

Native fluvial and diadromous fishes include: lampreys (Petromysonidae), sturgeon (Acipenser sturio), European eel (Anguilla anguilla), Allis shad (Alosa alosa), Twaite shad (A. fallax), Atlantic salmon (Salmo salar), brown trout and sea trout (Salmo trutta), barbels (Barbus spp.), bogas (Chondrostoma spp.), chub or cacho (Leuciscus cephalus), tench (Tinca tinca) and grey mullets (Mugilidae).

Introduced fishes include: rainbow trout (Oncorhynchus mykiss), American brook trout or char (Salvelinus fontinalis), huchen (Hucho hucho), common carp (Cyprinus carpio), crucian carp (Carassius carassius), gudgeon (Gobio gobio), pike (Esox lucius) and largemouth black bass (Micropterus salmoides).

Crayfish (congrego), Astacus and Cambarus sp., are also an important aquatic species in Spain. They are sometimes called “river crabs” in Spanish publications written in English.

Brown trout are perhaps the most widely distributed species in Spain, although obviously confined to cold waters especially those of northern streams, mountain areas and the upper areas of the rivers.

The northern coast of Spain contains a number of fine salmon rivers, and the Miño is the approximate natural southern extent of this species (Muus and Dahlstrom, 1975). Spain once had about 50 fine salmon streams but after the tenth century the runs became heavily exploited through the use of weirs and fish traps. Grist mills of the nineteenth century and water diversions followed by the construction of hydroelectric dams, further decimated the stocks as did illegal fishing, overfishing (e.g., in estuaries), and water pollution. By the early part of this century, salmon had almost vanished from the Miño, and the following Spanish Civil War (ca 1939) contributed to the decline, confining salmon to about 20 streams.

In 1942, when salmon fishing in Spain had declined to catches of only about 2 000–3 000 per year, nets were banned from rivers and estuaries. Spain is now the only European country that has completely banned netting in its rivers and turned them over completely to angling. However, professional (commercial) fishing using rod and reel is allowed in some areas and only salmon from “free” areas can be sold. The rivers are divided into cotos (preserves) and free waters. Cotos are divided into beats and permits are necessary. Riparian rights prevail on free waters.

7.1 Capture Fisheries

Table 6 illustrates the catch from Spain's inland waters during the 1965–87 period as compiled for FAO's Yearbook of Fishery Statistics.

The Yearbook's statistics are not intended to include “recreational” catches. Nevertheless, following a review of the Yearbook's 1965–74 figures, Spain/EIFAC (1977) stated that during this period, the following percentages of these fish were taken by angling: cyprinids, 75 percent; eel, 5 percent; Atlantic salmon and trout, 100 percent¹. It also provided the material for Table 7, which shows the official governmental statistics for Spain's Atlantic salmon catch. A comparison of these with the figures in Table 6 demonstrates some of the difficulties in accepting the FAO yearbook statistics, especially those for the early years when FAO reduced small catches, even if reported by the countries, to categories such as “negligible” or “insignificant”.

¹ Commercial (professional) fishing for Atlantic salmon is, however, by “angling”, i.e., with rod and line, normally a recreational or sporting activity

It is also obvious that most of the trout “catch” in Table 6 is aquacultural production (see section 7.2).

Table 6

Nominal catches by species in the inland waters of Spain 1965–87
(in tons)

0 Probably nil, negligible or insignificant; or less than 50 t during the 1965–73 period, or less than half a ton during later years
- This category not listed this year

Source:   1965–69: Yearb.Fish.Stat.FAO, 36 (Publ. 1974)
1970–83: FAO Fish.Dept.Fishery Statistical Database (FISHDAB)
1984–87: Yearb.Fish.Stat.FAO, 64 (Publ. 1989)

7.1.1 Commercial fishing

In addition to the catches from inland waters recorded in Tables 6 and 7, two other tables (8 and 9) are provided to show the catches by Spain in two marine statistical areas of fishes found in both fresh and saline waters: European eel, shads and grey mullets.

No data other than those provided above are available to the author on the subject of commercial fishing in inland waters of Spain but from all indications, it appears to be a very small industry.

Table 7

Catches (by angling) of Atlantic salmon in the inland waters of Spain 1965–76

Source: Spain/EIFAC (1977)

7.1.2 Sport fishing

Fishing in Spain for Atlantic salmon - a principal attraction for foreign anglers - is now primarily confined to 14 principal salmon streams. Almost all of these originate in the Cantabrian Cordillera and flow north, mostly as short, swift rivers, to the Atlantic Ocean: the Ason, Deva-Cares, Canero, Eo Lérez, Masma, Narcea, Navia, Pas, Sella and Ulla. The Bidasoa, shared with France, and the Miño, shared with Portugal, are also salmon streams. Collectively, they produce about 4 000 salmon annually.

Salmon can be taken only by angling, but the methods include the use of natural baits (minnow, worm and prawn) and artificial lures including flies. There are a considerable number of rules concerning catch.

Trout fishing includes angling for resident brown and anadromous sea trout (Salmo trutta) and the introduced rainbow trout. The introduced huchen and American brook trout or char also provide limited trout angling. Huchen, for example, introduced from Czechoslovakia in 1968, provides some trophy fishing in the Tormes River. In northern Spain there are about 75 main trout rivers offering over 15 000 km of water but there are isolated trout rivers even in southern Spain. Among the better trout rivers are all the salmon rivers (see above), the Esla and tributaries, the Ucero, Pisuerga, Iregua, Najenilla, Cega, Adaja, Alberche, Segre, Ter, Gallego, Tietar, Ega and Duratom. The construction of access roads and fishing huts (“refugios”), employment of stream guards and maintenance of a hatchery system facilitate this angling.

Cyprinids are also utilized as sport fish, especially in middle and lower stream courses and in static waters: barbels, “bogas”, chub or “cachos”, common carp and tench. Pike and largemouth bass are also fished, especially in lakes and reservoirs.

The lower parts of some rivers and brackish waters provide sport fishing for: lampreys, European eel, shad (especially in the Miño) and grey mullets.

Crayfish (congregos) are also utilized by sport fishermen. In 1976, the number of permits issued by ICONA for trout and crayfish fishing was almost equal to the number of permits issued for trout and salmon fishing.

There is a good deal of managed water in Spain for sport fishing, including the system of cotos which allows regulated angling on a permit basis. As of 1976, there were 736 cotos in Spain: 98 for Atlantic salmon and trout, 430 for trout, 97 for trout and crayfish, 32 for crayfish and 79 for other species. By 1980, there were 791 cotos in Spain. Of these, 572 were directed by the National Institute for the Conservation of Nature (ICONA), 197 with the collaboration of recreational societies, 9 were leased to the Secretariat of State for Tourism, and 13 were concessions to syndicates of professional fishermen.

The number of sport fishermen (licensed anglers) more than tripled between 1966 and 1976, i.e., from 224 005 to 706 545. (About 504 000 of the latter number were for salmonids.) Despite this gain, the total number of licensed sport fishermen constituted only about 2.1 percent of Spain's total population. By 1979 the number was 764 517 and in 1980 the number was only 709 534.

The economic importance of angling is well recognized in Spain and the Spanish Directorate for the Promotion of Tourism promotes angling for foreigners.

7.2 Aquaculture

As pointed out in section 5.4, the Spanish lagoon fisheries are primarily capture fisheries, although the construction of barrages to permit the assembly of fry and descent of adults may be considered a primitive type of aquaculture. There have also been attempts to convert old salt pans near Cadiz to the pond culture of euryhaline fishes (ADCP, 1979).

Extensive polyculture has been practised here: gilthead (sparus auratus), sea bass (Dicentrarchus labrax), eel, sole (Solea vulgaris) and grey mullets (Mugil spp.). Fry raising begins with the natural capture of fry in tides entering through sluicegates during the winter and early spring. During the second phase, lasting about seven months, the fish eat natural food in the esteros or rearing ponds, and are then fished during the winter by emptying the ponds (Arias, Drake and Rodriguez, 1984).

Rice field fish culture was also tried out in some parts of Spain, presumably using carp, but was apparently abandoned (Coche, 1967).

There is some culture of tench according to FAO, Fish, Info., Data and Stat.Serv. (1991).

Eel culture is carried out on the Ebro delta and on the Bay of Cadiz with eels raised in tanks (San Feliu, 1973). There has also been some experimental culture of Atlantic salmon, produced in fresh water to be grown out in saltwater pens, and culture of Coho salmon (Oncorhynchus kisutch). There is also a small crayfish farming industry in Spain.

Intensive culture of fish for food in Spain is, however, concentrated on rainbow trout, and has been strongly developed only since 1965. See Table 10 for Spanish production of table trout since 1974. By 1976, there were 118 private trout hatcheries (Spain/EIFAC, 1977) with an annual production of 6 000 t. By 1982, there were 169 private trout farms producing 11 000 t (Richards, 1982). Most of the Spanish trout farms are in the northern part of the country and both spring and river water are used. The trout, which spawn during the October–March period, are grown out in concrete raceways or earthen ponds. Fed on pellets, the majority are harvested at an age of about 15 months at a size of 200 g, although a few are raised to two or three kg to be smoked. Most of the fish are sold in the round, packed in ice, and sold to fish markets. Little or no fee fishing exists (Brown, 1983). There are some specialized manufacturers of fish feeding and aquacultural equipment.

Table 8

Nominal catches of diadromous fishes and grey mullets in Marine Statistical Fishing Area 27 (Northeast Atlantic) by Spain 1965–87 (in tons)

0: Probably nil negligible or insignificant; or less than 50 t during the 1965–73 period or less than half a ton during later years
- This category not listed this year

Sources: 1965–69: Yearb.Fish.Stat.FAO, 36 (Publ. 1974)
1970–83: FAO Fish.Dept. Fishery Statistical Database (FISHDAB)
1984–87: Yearb.Fish.Stat.FAO, 64 (Publ. 1989)

The latest figures available to the author of inland aquacultural production in Spain are shown in Table 11.

In addition to this commercial production for food, ICONA had 36 fish hatcheries in 1980 to restock open waters. The restocking programme has comprised the following species: Atlantic salmon, brown trout, American brook trout or char, black bass, pike and tench.

Table 9

Nominal catches of diadromous fishes and grey mullets in Marine Statistical Fishing Area 37 (Mediterranean) by Spain 1965–87 (in tons)

0: Probably nil negligible or insignificant; or less than 50 t during the 1965–73 period or less than half a ton during later years

- This category not listed this year

Sources:  1965–69: Yearb.Fish.Stat.FAO, 36 (Publ. 1974)
1970–83: FAO Fish.Dept.Fishery Statistical Database (FISHDAB)
1984–87: Yearb.Fish.Stat.FAO, 64 (Publ. 1989)

Table 10

Estimated production of cultivated trout in Spain 1974–89 (in tons)^a

^a Listed either as “trout”, “table trout”, “rainbow”, or “portion-sized trout”
^b Information from Associazione Piscicoltori Italiani, Bolletino di Informazioni (6), Giugno 1978

Table 11

Production from aquaculture of inland species in Spain, 1986–89 (in tons)

^a brackish water fish
... not available
0 more than zero but less than half a ton
^F FAO estimate

Source: FAO, Fish.info., Data & Stat.Serv., (1991)

8. OWNERSHIP, ADMINISTRATION, MANAGEMENT, INVESTIGATION AND AGREEMENTS¹

¹ This section is derived primarily from Arrieta (1979), Gaudet (1974), material received by EIFAC from Spain in 1979, and Secretaria de Estado de Turismo (1980). It may not be up to date

8.1 Ownership

Under Spanish law, and as a rule, all flowing waters, whatever their importance, form part of the Public Domain from their source until they discharge into another stream or the sea. Public waters are considered common property insofar as use is made thereof for essential vital needs such as drinking or washing. Private waters make up an insignificant percentage in Spain.

8.1.1 Public waters. In general, these include: (i) “watercourses” and other natural beds, i.e., large streams whether permanent or temporary; (ii) perennial or intermittent water of springs and small streams (arroyos) and their natural beds; (iii) perennial or intermittent waters with sources on land of Public Domain; (iv) permanent or intermittent waters after they have left the land on which they have their source, and (v) lakes and lagoons and their flood zones formed naturally on public domain.

8.1.2 Private waters. In general, these include: (i) perennial and intermittent springs arising on private lands as long as they continue to flow thereon; (ii) lakes and lagoons and their flood zones naturally formed on private lands, and (iii) perennial and intermittent streams fed from rainwater and small streams flowing on nonpublic land.

8.1.3 Aquatic flora and fauna. As with most inland waters in Spain, the flora and fauna also belong to the Public Domain.

8.2 Use and Availability of Water

8.2.1 In granting public use concessions, the following order of priority is applied: (i) city water supply; (ii) railway supply; (iii) irrigation; (iv) navigation canals; (v) industrial uses and river crossings, and (vi) reservoirs for stock watering and fish breeding. Under Spanish law a distinction is made between common and special uses of water. Common uses include fishing, domestic and household use, small navigation and floating.

8.2.2 Fishing. There are two general types of fishing waters: (i) those submitted to general fishing regulations, and (ii) those such as preserves or private waters, which are under special control.

The basic principle governing fishing in public watercourses is that access thereto is free, providing that laws and regulations are respected and there is no interference with navigation and floating. Access to public canals, ditches and aqueducts is also free for fishing unless the concession holders have duly reserved their own fishing right in terms of the concession. Fishing is limited to legal methods.

8.2.3 Fish breeding. Authorization to use public waters for fish breeding may be granted only if no harm is caused thereby to public health or any other prior downstream use.

8.3 Administration

The Ministry of Agriculture has overall responsibility for conservation and development of inland fisheries in Spain. Within this Ministry, the National Institute for the Conservation of National Resources (ICONA), which is specifically charged with conservation and development of Spain's inland fisheries, contains several bodies concerned with inland fisheries.

The Division of Renewable Natural Resources, vested with the direction of inland fisheries, includes: (i) a National Fisheries Inspectorate, and (ii) an Inland Fisheries Section.

The Nature Protection Division is occupied with the technical application of investigation (see section 8.5).

The executive functions of ICONA are carried out by 50 Provincial Chiefs, and there are 11 Regional Inspectorates.

8.4 Management

The Administration is not only responsible for conservation and development of public waters but also controls the exploitation of private waters that can affect public waters.

In order to fish in inland waters, whether public or private, a regional or national licence must be obtained from ICONA through its Provincial Chiefs. Aside from this, the Administration requires additional permits for fishing in certain stretches of rivers or waters that it controls. A licence is necessary to fish any type of water: general or special. It is necessary to obtain authority to fish from the owners if the property is private, or for reserves from ICONA or, in some cases, from the Tourist Administration. Licences may be issued either to residents or foreigners.

ICONA promulgates various regulations, directs cotos (see section 7.1.2) and owns installations to restock fishing waters (section 7.2).

8.5 Investigation

Although a decree-law of 1971 entrusted pure scientific research of the Ministry of Agriculture to the National Agricultural Research Institute (INIA), applied technical work, investigation and control were left to the Nature Protection Division of ICONA, which has an Ecology Section.

Research and development with respect to aquaculture in coastal lagoons are conducted by the Instituto de Investigaciones Pesqueras (IIP) of the Ministry of Education and Science and the Instituto Español de Oceanografia (IEO) of the Ministry of Commerce.

8.6 Training

Various colleges and vocational schools offer training in fisheries and aquaculture, and there is also liaison with other countries.

8.7 International Agreements

Spain has a bilateral agreement with Portugal concerning uses of their boundary or common streams with respect to hydropower, water supply and water quality.

9. STATE OF THE FISHERY

9.1 Yield

According to FAO's inland water catch statistics for Spain in Table 6, during the period from 1965 to 1987, the catch of cyprinids almost doubled (from 9 000 to 17 000 t in 1980), and then declined to only about 5 000 t. Meanwhile the trout “catch” became ten times greater (from 1 800 to over 18 000 t) and the catch of European eel fell to one-eighth (150 t) of its 1 200-t catch in 1965. One must view all these apparent changes with caution, especially in consideration of the statements made by Spain/EIFAC (1977) concerning the percentages of these fish taken by angling (section 7.1). The author's surmise is that - aside from inaccuracies and differences in reporting methods and sources - cyprinid catch may have first increased with reservoir construction, and it is well known that the increased trout “catch” actually represents in large part the addition of cultivated fish (see section 7.2). Why the reported catch of eel declined is unknown.

There is no question but that the catch of salmon in Spain has fallen drastically. A century ago there was an annual catch of perhaps 30 000–50 000 salmon annually, and even during the period of 1965–76 the catch was halved in both numbers and weight (Table 7).

Yields from individual freshwater bodies in Spain are not at hand. In brackishwater lagoons, they seem low in large lagoons such as the 17 000-ha Mar Menor, where yields of only 25 kg/ha/year or less of finfishes are recorded in recent years, or in the 3 114-ha Albufera at Valencia, where the finfish yield is only about 81–83 kg/ha/year. In the smaller Ebro delta lagoons, the average yield of finfishes was 275 kg/ha/year in 1970–71 and 171 kg/ha/year during the 1966–76 period. One of the highest lagoonal yields was that of 471 kg/ha/year in the 179-ha Tancada in 1970–71.

9.2 Factors Affecting the Fishery

About one half of Spain is actually semi-arid and only the north and northwest have pluviose climates. The total average run-off from rainfall is quite small, virtually no water is contributed by the contiguous countries, and the evaporative rate is generally high. The total water resources of Spain are, therefore, not large with respect to the size of the country and its requirements.

Furthermore, the total inland water area is very small: only about one percent of the country's total area. Spain is sorely lacking in natural lakes, except for some high mountain tarns and has few extensive estuaries. The fluvial inland fisheries are, therefore, confined primarily to rivers and reservoirs. Unfortunately, most of the rivers are subject to great fluctuation in volume but the reservoirs are gaining in importance.

Spain has a more limited freshwater fish fauna than most of continental Europe and populations under natural conditions are not abundant. Salmon populations, due both to overexploitation and reduction of favourable habitat, are now only marginal and confined to a few northern rivers. Trout populations under controlled management are more persistent and the native brown trout has been supplemented by other species. Similarly, the introduced pike and black bass provide a greater variety of fishing than once existed. Lack of water is still more important in determining Spain's fishing than is lack of species.

The general fertility of the waters, especially in eastern Spain, is reasonably good, and there is a relatively long growing season for fish. Except in the high mountains most waters are accessible for fishing throughout the year and year-round fishing is permitted for most species. (The legal seasons for trout and salmon are quite restricted, however.)

As in Portugal, dynamiting and other illegal methods of taking fish have harmed the stocks in some areas.

Spain's scarce water resources have received heavy use for many years - albeit, originally with rather primitive methods, e.g., in some areas such as Catalonia water mills were once so common that long stretches of river bed were practically waterless. Today irrigation places severe demands on streams and hydroelectric dams and diversions have also affected fish populations. Industrial and domestic use of water is ever-increasing.

Pollution from a variety of sources is a serious problem in Spain. Circa 1970, 37 percent of the total river length in Spain was reported to be polluted to the extent that the fisheries were affected and 7 000 km had been rendered fishless (Holden and Lloyd, 1972). A later report by ICONA stated that of the 72 000 km of permanent streams in Spain, 8.3 percent (6 000 km) were very contaminated, 15.3 percent (11 000 km) were moderately contaminated, and 76.4 percent (55 000 km) were little or not contaminated (Spain/EIFAC, 1977). Inadequate treatment accounts for some of the problem. Climatic conditions are also conducive to sudden outbursts of pollution. The first heavy rainfalls after drought wash a large amount of land and road-accumulated polluting material into the rivers.

The average annual surface run-off from rainfall of about 1 912 m³ per caput is well below the European average, and does not afford a high degree of effluent dilution. This figure is based on a surface run-off of 76 000 million m³ but even if one includes the groundwater discharge into streams to raise the total run-off to 94 150 million m³, the annual run-off per caput is still only 2 369 m³.

Freshwater fish consumption has not been traditionally high in Spain. Only in the north and northwest were there originally runs of the anadromous salmon, and their common use as food declined many years ago. Lack of natural lakes has also accounted for the small commercial fisheries in Spain's inland waters. Spain has also comparatively few anglers as compared with northern European countries and automobile ownership for their transport is low.

Fish culture does not possess a long tradition of use in Spain which, despite its continental character, has a high per caput consumption of marine fish. Not only is Spain a leading producer of marine fish but about one-half of its sea catch is marketed fresh or chilled and transported throughout the country. Thus, the sea fisheries and even marine aquaculture, especially for mussels, have been more important than freshwater fishing or fish culture in Spain. Only the culture of rainbow trout has increased decidedly in the last years.

Finally, with respect to capture fisheries, it should be noted that the Miño, Guadiana, Duero and Tajo are international rivers shared between Spain and Portugal, subject through treaty to their joint use, and with access to the upper stretches of the two latter streams controlled by the lower riparian country.

9.3 Prospect

Spain's mountainous terrain indicates that the country is well suited for hydroelectric development and one might infer that this would insure further construction of reservoirs suitable for fishing. However, low rainfall restricts the capacity of Spain's reservoirs, most of the profitable hydroelectric capacity has been developed, and the use of water for irrigation is awarded priority over that of hydropower. The country, which possesses a source of uranium, is therefore turning to nuclear power.

Although this will slow down the continued effect of hydroelectric construction (both favourable and unfavourable) on fisheries, the control of surface water for various uses will still continue particularly since really good aquifers are non-existent in Spain and groundwater cannot be expected to greatly supplement surface flows for future needs. Thus, it is estimated that the 37 480 million m³ of water controlled in 1967 can be increased to 70 500 million m³ (Heras, 1970). Furthermore, transbasin transfers of water are planned to overcome so-called water deficits for drinking water, irrigation and industry. Much of the transfer is being done by development on smaller rivers and includes development of marginal hydroelectric resources together with pumped storage. These transfers, primarily north to south and east to west, will involve complex structures that will obviously affect the fisheries. There will be transfers of stocks and possible losses at diversion or exchange points. Among the transfers are: Tajo River to Segura River, and Ebro River to the Júcar and Pyrenees Orientale drainages. However, given opportunities for water regulation which will aid fish production and institution of improved forms of management, reservoir fisheries can undoubtedly be developed to a far greater extent.

Management, including restoration of trout and salmon waters, offers great dividends. Rental of salmon beats, although limited to a few anglers, can be lucrative.

Trout culture will be limited by facilities for hatcheries. Brown (1983) suggested that an annual production of 10 000–12 000 t could be obtained and that there might be some commercial salmoniculture. Such a production has already been obtained and it is certain that it will be increased.

The Government's aim is to increase fish farming not only for trout but in brackish water for euryhaline species. Until recently, coastal aquaculture in Spain has been dominated by mussel culture in which Spain has been a leader. Indications are that culture of euryhaline finfish as well as invertebrates will be augmented in future (see especially ADCP, 1979). Pond culture and use of closed circuits may make up for the high price of coastal lands and ecological degradation of brackish waters.

To a large extent, the future of inland fisheries in Spain depends upon a greater consideration of their value in making use of the country's limited water resources.

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