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The limits of the sea

Survey maps the excessive exploitation of fishing resources in Brazil

EDUARDO CESARThis year may be decisive for the fate of marine fishing in Brazil, above all in deep waters. From now until December, a network of 150 specialists from 40 Brazilian research institutions is beginning to deliver a series of reports that will make it possible to sketch out with unprecedented accuracy a strategy for the exploitation and preservation of the still little known potential for fishing off the Brazilian coastal waters. At the end of the studies, the federal government, which is financing the venture that is to consume more than R$ 15 million, will have information that will make it possible to resize and redirect, whenever necessary, the efforts dedicated to catching marine beings within an area of the ocean equivalent to a little more than 40% of Brazil’s continental territory.

In a simplified fashion, this broad X-ray aims to answer – always with the best scientific data possible and without harming the basic principle of rational exploitation of the aquatic species – the following queries of a practical nature: what, how much, where, when and how to fish inside this enormous maritime strip under Brazilian jurisdiction.

Comprehensive and ambitious, the Program for Assessing the Sustainable Potential for Living Resources in the Economic Exclusion Zone (Revizee), this project’s formal name, has still not agreed on a final verdict on the situation of the stocks of the main types of fish and other animals of commercial value found in the area of the ocean in question. Even with its conclusion extended to the end of this year, the project has already produced results on the situation of species of great commercial interest. This preliminary data shows that it will not be easy to increase in any significant – and non-predatory – way the quantity of marine fishing caught by Brazil in its Exclusive Economic Zone (EEZ).

This term designates a new international concept, in force since 1994, which controls the use of oceanic resources in a strip that starts where a country’s territorial waters end – 12 nautical miles from the coast (22 kilometers) – and extends for another 188 nautical miles (some 350 kilometers) into the sea. In Brazil, the EEZ comes to as much as 3.5 million square kilometers.

To keep the exclusive rights over exploiting the resources in this area, the nation concerned must show that it has the capacity for exploiting it in a sustained manner, without having to open up its waters to other countries. Revizee was born in 1997, to mark out Brazil’s activity in this new and immense portion of sea. Its initial data indicates that the marine resources in national waters that are now a target for systematic fishing, in an industrial or even rudimentary fashion, are at their maximum limit for economic exploitation or have even passed this point.

Some examples of this tendency towards an exaggerated catch of resources from the sea. On the south-southeastern coast, the part of the Brazilian coastline that starts in Chuí, at the far south of the state of Rio Grande do Sul, and extends to Cabo de São Tomé, north of the state of Rio de Janeiro, the results of the studies on the potential for catching three economically important species – the blackfin goosefish (Lophius gastrophysus ), the tilefish (Lopholatillus villarii ) and the deep-sea crab (of theChaceon genus) – recommend a reduction in the fishing of these resources.

“The fishing boats often discover a new stock of a species in a region and start to exploit it so quickly that we hardly have time to study the size of this resource in detail”, says Carmen Rossi-Wongtschowski, from the Oceanographic Institute of the University of São Paulo (IO/USP), Revizee’s coordinator in this stretch of the coastline, from which comes half the marine fish caught in Brazil.

A little further up, in the central part of the Brazilian coast, between Cabo de São Tomé and Salvador, the picture is not very different. An analysis of the ten species most exploited at the bottom of the reefs and coral banks also revealed worrying data. “Our numerical and mathematical models indicated that eight of these species are between being fully exploited and overexploited economically”, says marine biologist Jean Valentin, from the Federal University of Rio de Janeiro (UFRJ), the coordinator of the work in this stretch of the Brazilian coast. Even in the case of the two species that apparently show some potential for extra exploitation, the common dolphinfish (Coryphaena hyppurus ) and the greater amberjack (Seriola dumerilli ), the researchers do not believe that there are conditions for raising the level of their catch.

Going even further up, along the maritime platform of the other states of the northeast, where fishing is still predominantly rudimentary, the data likewise does not give room for an increase in the fishing business. “We have top quality fish in the region, but the quantity of resources is small”, sums up Rosângela Lessa, from the Federal Rural University of Pernambuco (UFRPE), responsible for the dynamics of populations and evaluation of stocks on the coast of the northeast, which runs from Salvador, the capital of the state of Bahia, to the estuary of the Parnaíba River, on the border between the states of Piauí and Maranhão, and includes the archipelagos of Fernando de Noronha, São Pedro e São Paulo and the das Rocas atoll. “Among the fish that are exploited economically today, like the red snappers and the dolphinfishes, none of them should be fished more than it is today”.

On the north coast, which goes from the Parnaíba estuary to the Oiapoque River, in Amapá, the marine resources are likewise with their populations under pressure, as a result of excessive fishing. “It is all at the upper limit, both the industrial catch of the pink shrimp (a species of the Penaeus genus), the laulao catfish (Brachyplatystoma vaillantti ) and of the red porgy (Pagrus pagrus), and the rudimentary fishing of the acoupa weakfish and of the ‘guarijuba’ (Tachysurus luniscutis )”, says Rosalia Cutrim Souza, from the Faculty of Agrarian Sciences of Belém, one of the researchers in Revizee working on the north coast.

According to Rosalia, the fleet intended for the industrial exploitation of the pink shrimp amounts to 200 boats, but there should not be more than 150. The professional fishing of the laulao catfish – a catfish from fresh and from brackish waters, up to 1.2 meters long, which in the past was the third most fished fish in the country – was so much out of control that, for the first time, between October 1st and November 30th, Ibama instituted for the first time a closed season for this species in the Amazon estuary. The closed season prohibits the catching of a fish at the most important time for its reproduction.

In Revizee, over 30 kinds of fishes and crustaceans are the target of studies to determine the size of their populations at various spots along the Brazilian coastline, and to see if there is any possibility for increasing their fishing, or if actually, it has to be restricted even more. The scientists have given preference to species that have been little researched. This option has meant that resources of great commercial importance that have already been the subject of many scientific works, such as sardines off the south-southeastern coast and lobsters in the northeast have not gone back to be a subject for detailed research by Revizee.

By the way: both the stocks of sardines and of lobsters are in a steep decline, because of being excessively fished. The quantity of sardines taken out of the coastal waters of the southeast has fallen from 200,000 tons a year, at the end of the 70’s, to some 20,000 tons in 2000. Species fished in international waters, like the tuna, have also been left out of Revizee’s work.

Logically, to offset the picture of exhaustion of fish resources overexploited today, the researchers from Revizee have discovered hitherto unknown stocks of new or old marine species. One of the differences of the project is precisely the promotion of studies on the marine resources that exist at depths that are practically unexplored by Brazilian science. “We had never worked below a depth of 200 meters, and in some cases we reached 1,800 meters”, comments Carmen Wongtschowski. “With Revizee, today we have a better photograph of this whole region”. The project has contributed decisively towards a better mapping of the so-called demersal resources of the Brazilian coastal waters, fish and other beings that live close to the bottom of the sea (the species that stay closer to the surface of the water are called pelagic).

In terms of new stocks, some results from this unprecedented prospect the seabed are now coming into sight. On the south-southeastern coast, for example, what calls attention is the existence of a stock, estimated at 1 million tons a year, of Maurolicus stehmani, popularly known as the torch fish. Only 5 centimeters in length, this species has no commercial value, but being a common food for tunas, is an indicator of the possibility of large shoals of this valuable fish. In the northeast, populations were also identified that have not yet been exploited economically of the so-called deep-sea crabs, of a species of the Chaceon genus, the same as the crabs found and abundantly caught in the south-southeast.

In the central part of the coastline, research cruisers have explored waters at a depth of between 60 and 750 meters, and have made it possible to discover new stocks of tilefish, snowy grouper (Epinephelus niveatus), coney (Cephalopholis fulva) and mutton snapper (Lutjanus analis). But here the levels of yield of these species are considerably lower than those achieved off the south-southeastern coast and in other parts of the world”, says Paulo Alberto Silva da Costa, from the University of Rio de Janeiro (Unirio), responsible for the area of fishing dynamics of Revizee on the central coastline. “For this reason, they do not mean any concrete possibility of increasing the local (fishing) fleet, which exploits them in a rudimentary fashion”.

Today, Brazil takes out about 470,000 tons of fish a year, including crustaceans and mollusks. With the addition of freshwater resources and the aquaculture projects in sea and fresh water, this figures goes up to 840,000 tons of fish a year. Is it a little or a lot? Suffice it to say that Brazil’s production is five times smaller than Chile’s, and less than one tenth of Peru’s, two countries with a large stock of fish. From tiny canoes to large ships, the Brazilian fishing fleet has some 25,000 vessels, excluding the 50 boats that make up the chartered fleet, made up of foreign ships that operate here legally, under contract to local ship brokers.

Some 800,000 people work in the Brazilian fishing sector, on which there is scarce data about total revenues. It is, however, known that in 2001 this segment of the economy produced a surplus in the balance of trade in the order of US$ 25 million – exports of fish amounted to the US$ 270 million mark, and imports came to some US$ 245 million. It is probable that the weight of the Brazilian fishing sector is a little greater than it appears in the available statistics. The figures referring to rudimentary fishing, on a small scale, carried out near the coast by local communities, are usually underestimated.

“The case of Rio de Janeiro is emblematic for what happens in the country”, says Carmen Wongtschowski. “Work carried out on the coastline of the north of Rio de Janeiro state and in Guanabara Bay show that the figures for unloading represent only some 30% of what is actually taken out of the sea”. But, for official purposes, the available figure is of 840,000 tons. Be that as it may, consumption of fish in Brazil is low, about 6 kilos a year per capita, some six times less than beef and poultry, which are more appreciated.

A layman, without any solid oceanographic knowledge, cannot understand how Brazil, with a coastline of some 8,000 kilometers in length, is not a fishing nation par excellence. But Brazilian waters, even though they are rich in biodiversity, do not enjoy the conditions for allowing the existence of many fish. Due to a series of peculiarities, such as the presence of fewer nutrients than those found in temperate waters, there are no great shoals along the coastline. This is one immutable fact of the reality of fishing, which explains, in part, the modest size of the sector.

Is there any real prospect of growth for fishing in Brazil, without putting the stocks of the marine species under pressure? According to the specialists, they are few and limited. At the beginning of Revizee, in 1997, it was estimated that the fishing potential of the Brazilian EEZ was in the order of 1.5 million tons of fish a year. In terms of coastal fishing, usually rudimentary, exploitation is at the upper limit. “As to the deep water resources, below 200 meters, there is some possibility of growth, but at levels that are never going to exceed 100,000 tons”, reckons Fábio Hazin, from the Federal Rural University of Pernambuco (UFRPE), Revizee’s coordinator on the northeastern coast.

With regard to the catching of fishes that live in oceanic waters closer to the surface (pelagic), such as tunas, swordfishes, anchovies and squids, Hazin believes that the increase could be a little more significant. “But nevertheless I do not believe we can reach the mark of 1.5million tons of fish a year”, explains the researcher from UFRPE.

Fishing in other regions, like Antarctica or the North Atlantic, may be one way out. Another option is to invest in breeding fish in salt and fresh water. “But the growth of aquaculture is happening in a disorderly way, without proper planning that takes into account the biological, hydrological, social and economic processes pertaining to the areas where they are implemented”, ponders Carmen Wongtschowski.

Victims of the gold rush

The reduction in the size of the stocks of two resources intensely exploited on the south-southeastern coast – the deep-sea crab and the blackfin goosefish – illustrates, in a way that is almost didactical, the kind of relationship that the Brazilian fishing industry usually keeps with commercially valuable marine species. The stories of this two new stars of fishing for export carried out in deep waters are quite similar and representative of the gold rush (the term is used by some scientists), which happens in the sea whenever someone “discovers” a valuable fish or crustacean, apparently abundant and hitherto little exploited economically or none at all.

Almost unknown to Brazilian consumers, but much appreciated abroad, the crab and the blackfin goosefish (or angler fish) began to be caught in a more systematic way in the second half of the last decade. Taken in conjunction, the average stock of the two species of deep-sea crabs – Chaceon notialis and Chaceon ramosae , crustaceans that can weigh over 2 kilos and account for this kind of resource on the south-southeastern coastline – is 23,600 tons, according to Alessandro Athiê, who is studying for a doctorate at USP’s Oceanographic Institute and did some specific work on these crabs.

“From our calculations, a rational exploitation of this population can stand the withdrawal of 1,150 tons a year of crabs, at the most”, says Athiê, who in 1999 spent a month on board the Japanese boat Kimpo Maru, the largest of the five chartered ships that are dedicated to catching this crustacean in Brazilian waters.

The recommendation from Revizee’s reports clashes with the reality, since Kimpo Maru alone removes this quantity of crab every 12 months. At the moment, the fishing of this resource is carried out with great effectiveness, usually at depths of over 200 meters, with the help of a kind of circular trap called a pot. “To complicate this picture even more, the stock of crabs of the C. notialis species, found in the far south of the country, is shared with Uruguay”, Athiê notes.

The case of the blackfin goosefish – as ugly as it is delicious, avow those, like the Europeans, have already tried the meat of this marine delicacy that can come to over half a meter in length – is equally worrying. Work carried out by researchers from the University of the Itajaí Valley (Univali), a private institution from Santa Catarina, estimated that the average stock of Lophius gastrophysus on the south-southeastern coast was 61,000 tons two years ago. According to the study, some 8,600 tons of blackfin goosefish, roughly 15% of the total population of the species, were caught in just one season, in 2001.

Another estimate, made by biologists involved in Revizee, indicates that the quantity of this resource in the same stretch of the coastline is even smaller. On the basis of these two studies, at the end of last year, scientists, ship brokers and the Ministry of Agriculture, which legislates on the fishing activity, arrived at a consensus to diminish the predatory fishing of the blackfin goosefish. Amongst the measures agreed, the highlights are the laying down of a limit of 1,500 tons for catching this resource in 2003, and the demarcation of two exclusion zones, when the species may not be caught; it is normally fished with trawl-nets and encircling gillnet at depths of more than 200 meters.

To estimate the size of the stock of a species and how much this population can be fished in a year on a sustainable basis, the researchers from Revizee have to produce or discover a series of biological data on the resource under analysis. They have to get to know, for example, the species’ life expectation, its reproductive cycle, the places where it spawns, and its favorite habitat, among other pertinent information. According to the specialists, it is also indispensable to have a more detailed understanding of the degree of efficiency of the fishing methods used to take possession of this resource. This can be obtained through an analysis of the official figures for the catch of the species under study, or with information gathered in loco by scientists taking part in research trips.

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