Chartered trawling on the Brazilian slope.
|Abstract:||Commercial trawling on the Atlantic slope areas off Brazil intensified in the late 1990's owing to the expansion of coastal trawling areas and the operations of a chartered foreign fleet. Between 2000 and 2003, 59 fishing trips conducted by 10 chartered trawlers were intensely monitored by observers and satellite vessel monitoring systems, totaling 9,069 tows and 30,085.2 trawling hours. Fishing operations occurred in northern, northeastern, southeastern, and southern sectors of the Brazilian coast in 60-1,173 m depths. Total retained and processed catch were 8,074.6 t and 6,479.8 t, respectively. Argentine hake, Merluccius hubbsi; and Argentine shortfin squid, Illex argentinus, were the primary species taken contributing to 41.1 % and 28.6% of the overall catch, respectively. The silver John dory, Zenopsis conchifera; monkfish, Lophius gastrophysus; Brazilian codling, Urophycis mystacea; and the black grouper, Epinephelus nigritus, composed 23% of total processed catch, and the remaining 7.2% was composed of deep-sea shrimps (family Aristeidae) and other teleosts and elasmobranches. The occupation of slope areas included an early exploratory phase, followed by directed phases of the upper slope (300-500 m), aiming principally at the Argentine hake, and the lower slope (>700 m), targeting valuable concentrations of deep-sea aristeid shrimps. The role of chartering for slope trawling development was critically addressed. We conclude that chartered vessels were efficient explorers and were particularly important in areas not available to the technologically limited national fleet. Because the charters were market-oriented and had elevated profit demands, however, those vessels quickly turned from exploration to exploitation and competed with national trawlers in shallower areas and produced significant impacts on Brazil's modest deep-sea resources.|
(Laws, regulations and rules)
Shrimps (Laws, regulations and rules)
Fish industry (Laws, regulations and rules)
Fisheries (Laws, regulations and rules)
Fishery conservation (Laws, regulations and rules)
Perez, Jose Angel Alvarez
Pezzuto, Paulo Ricardo
|Publication:||Name: Marine Fisheries Review Publisher: Superintendent of Documents Audience: Academic Format: Magazine/Journal Subject: Agricultural industry; Business Copyright: COPYRIGHT 2009 U.S. Department of Commerce ISSN: 0090-1830|
|Issue:||Date: Spring, 2009 Source Volume: 71 Source Issue: 2|
|Topic:||Event Code: 930 Government regulation; 940 Government regulation (cont); 980 Legal issues & crime Advertising Code: 94 Legal/Government Regulation Computer Subject: Government regulation|
|Product:||Product Code: 0913080 Shrimp; 0900000 Fishing, Hunting & Trapping NAICS Code: 114112 Shellfish Fishing; 114 Fishing, Hunting and Trapping SIC Code: 0913 Shellfish; 0912 Finfish; 0919 Miscellaneous marine products; 0921 Fish hatcheries and preserves|
|Geographic:||Geographic Scope: Brazil Geographic Code: 3BRAZ Brazil|
Large-scale trawl fishing development around the world has been principally associated with the occupation of productive continental shelf areas (<200 m). The continental slope (200-2,000 m) has been less accessible to trawl fishing owing to the steep and often irregular topography and the generally discrete distribution patterns of targeted fish and shellfish within this area (Gordon et al., 1995; Merret and Haedrich, 1997). In the North Atlantic, although slope trawling was already practiced by Soviet and German vessels by the 1970's, the activity increased nearly 10 years later as the abundance of most shelf resources were greatly reduced and their catch was restricted by intensive regulation (Troyanovsky and Lisovsky, 1995; Gordon, 2001; Gordon et al., 2003). Essential to the process was the identification of profitable deep-water targets, the development of technology to overcome market limitations, and the progressive availability of charts depicting flatter grounds suitable for safe trawling (Gordon et al., 1995; Pineiro et al., 2001). Led by French trawlers during the 1990's, a multispecies deep-water fishery was well established in areas 800-1,600 m deep mostly in the northeast Atlantic (Charuau et al., 1995; Iglesias and Paz, 1995; Gordon, 2001; Pineiro et al., 2001; Lorance and Dupoy, 2001). In the tropical southwest Atlantic, however, another decade would go by before any effective commercial deep-water trawling activity was documented.
The continental shelf off Brazil encompasses 911,000 [km.sup.2] bathed mostly by southwest Atlantic waters. Its width varies along the nearly 8,000 km length of the country's coastline being particularly broad at the northern, southeastern, and southern sectors (Rossi-Wongstchowski et al., 2006). In all these sectors, trawling regimes have been established since the 1960's, basically supported by productive shelf stocks like penaeid shrimps, Farfantepenaeus spp., and demersal sciaenids (Haimovici et al., 2006a). For nearly 40 years these regimes were confined to the 100 m isobath (Perez et al., 2001), except for scientific surveys that, during this period, mapped slope areas and revealed a few potential resources of uncertain productivity and profitability (Haimovici, 2007).
The interest on occupying deeper waters only arose as a pattern in the national fishing industry when regional trawl fleets, particularly of the southern and southeastern coasts, began to experience economic losses due to overfishing of their main targets and were forced to look for alternatives (Perez et al., 2001). By the late 1990's, a significant number of shrimp and fish trawlers had conducted commercial operations at the shelf break, 100-200 m deep, exploiting profitable multispecies concentrations of pink cusk-eel, Genypterus brasiliensis; flounders, Paralichthys spp.; skates, family Rajidae; shrimps, Plesionika longirostris, and lobsters, Metanephrops rubellus (Perez and Pezzuto, 2006). A few years later, these same vessels trawled to 200-400 m depths of the slope, first targeting monkfish, Lophius gastropkysus, concentrations and later including Brazilian codling, Uropkycis mystacea; Argentine hake, Merluccius hubbsi; and Argentine shortfin squid, Illex agentinus (Perez et al., 2002a; Perez and Pezzuto, 2006).
As the regional Brazilian fleets were gradually occupying slope grounds, they were joined by foreign trawlers chartered by national companies as part of a deep-water fishing development program promoted by Brazilian authorities (Perez et al., 2003). These vessels were authorized to operate within the Brazilian Exclusive Economic Zone (EEZ), off the 200 m isobath, and were fully monitored by observers and satellite vessel monitoring system (VMS) in accordance with government regulations.
This paper describes the slope trawling fishery conducted by chartered vessels off Brazil between 2000 and 2003, including the physical characteristics of vessels and gears, the definition of main targets, the strategies of fishing ground occupation, and spatial and temporal patterns of catch, effort, and catch rates. Along with a previous assessment on the slope-trawling fishery conducted by national vessels (Perez and Pezzuto, 2006), this review is intended to improve our understanding of the status and perspectives of this new deep-water fishing era in Brazil and to critically address the costs and benefits of the chartering policies in such a process.
Data Sources and Analyses
Analyzed data is from the Chartered Fleet Observers Program developed by Universidade do Vale do Itajai as part of a scientific cooperation project with Brazilian fishing authorities (Ministry of Agriculture and Special Secretariat for Aquaculture and Fishery). All 59 fishing trips conducted by 10 chartered trawlers between 26 October 2000 and 20 October 2003 (Table 1) were monitored by observers assigned to collect, after each tow, information on fishing areas (position and depth), effort (tow duration), and catch composition. All retained species were identified on board and also on land, through collected specimens and photographic/videographic material. Catches were recorded in "processed weight" and later transformed into "live weight" using conversion indices for each species, as defined by the vessel's crew and/or experimentally by the observers aboard. Catch rates were expressed in kg per trip and kg per hour.
The main targets of chartered trawlers off Brazil were assessed using the method proposed by Biseau (1988). This method quantified, initially, the proportion taken by each species in the total biomass retained by each tow ([c.sub.i,s]) as follows:
[c.sub.i,s] = [T.sub.i,s]/[T.sub.i] x 100 (1)
where [T.sub.i,s], is the total biomass of species s in the tow i and [T.sub.i] is the total biomass obtained by tow i. [c.sub.i,s] is then pooled by truncated classes of 1 to 100%, each one denominated Level of Qualification (LQ), and, for each [j.sup.eth] LQ, the sum of the total biomass is calculated for each species s ([TC.sub.j,s]). Finally the following equation
[P.sub.j,s] = [TC.sub.j,s]/[T.sub.s] x 100 (2)
where [T.sub.s] is the total landed biomass of species s, calculates the relative contribution (in percentage) of each LQ to the total catch of species s in one fishing trip ([P.sub.j,s]).These contributions are presented in a cumulative frequency distribution whose form allows an assessment of the level of directionality of each tow to the retained species (Biseau, 1988).
Catch, effort, catch rates, and fishing targets were analyzed by vessel. Tows conducted in the southeastern and southern sectors of Brazilian coast were also grouped by latitudinal strata (North, north of lat. 25[degrees]S; Center, between lat. 25[degrees] and 29[degrees]S; South, south of lat. 29[degrees]S); depth strata (<200 m; 200-399 m; 400-599 m; >600 m); trimesters (I: Jan.-Mar.; 11: Apr.- June.; III: July-Sept.; IV: Oct.-Dec.), and years (2000, 2001, 2002, and 2003).
The chartered trawlers operating off Brazil from October 2000 to October 2003 originated from Spain (7), Portugal (1), Republic of South Korea (1), and Namibia (1). These vessels are described in Table 2. Three vessels (Joana, Insung 207, and Arneles) were noticeably larger (57-76 m long), with powerful engines (1,700-2,200 hp), and able to carry 30-41 men crew and to store 320-692 t of frozen fish. The remaining seven vessels were less robust, running 28-39 m long, 490-1,200 hp engines, 16-20 men crew, and store 75-145 t of frozen fish. Except for the trawler Arneles that could operate continuously for 120 days at sea, the chartered trawlers autonomy ranged between 24 and 80 days. All chartered trawlers operating in Brazil were built between 1969 and 1998, being 3-32 years old in 2001.
[FIGURE 1 OMITTED]
Two Spanish vessels (Cipi and Hermanos Vaqueros) were side trawlers, whereas all the others were stern trawlers. Side trawlers and stern trawlers were single- and double-decked, respectively. In the latter, the lower deck was sheltered and used for catch processing. Various trawl nets were used. Head rope and ground rope dimension ranges were 33-101 m and 41-120 m, respectively (Table 3). Mesh was made of braided or twisted polyethylene and measured 50-120 mm at the cod-end (stretched mesh). These nets were towed at 2.3-3.5 knots and their estimated vertical opening ranged from 3 to 15 m. Doors used weighed between 500 and 2,500 kg. On rough grounds, some trawlers used steel or rubber bobbins at the ground ropes (200-500 mm in diameter). Chains could replace these bobbins when fishing was conducted over smooth, soft ground.
Chartered trawlers conducted 59 fishing trips between 2000 and 2003 (Fig. 1) totaling 9,069 tows and 30,085.2 trawling hours (Table 1). Fishing operations occurred in northern, northeastern, southeastern, and southern sectors of Brazilian coast in areas 60 to 1,173 m deep (Fig. 2, 3).
[FIGURE 2 OMITTED]
In the southeastern and southern coast, nearly 70% of the tows conducted by the chartered trawlers were between lat. 23[degrees]S and lat. 25[degrees]S, whereas a secondary fishing area was between lat. 26[degrees]S and lat. 29[degrees]S (Fig. 3A). Similarly 60% of the total tows were conducted on 300-500 m deep grounds and a secondary depth was at 700-800 m isobaths for 20% of the tows (Fig. 3B). Occupation of the southern and southeastern slope areas resulted in the establishment of three main fishing grounds characterized by concentrations of the most abundant and/or valuable species: Argentine hake, Argentine shortfin squid, and the deep-sea shrimps (family Aristeidae). This process occurred in three consecutive phases: Exploratory, Directed (upper slope), and Directed (lower slope).
Exploratory phase: Established between late 2000 and mid 2001, this phase included the first operations of the trawlers Joana and Insung 207, which conducted tows along the entire southeastern-southern Brazilian coast between 100-400 m depths (Fig. 3A, 3B). In early 2001, the trawler Joana abandoned the Brazilian waters (Fig. 1).
Directed phase of the upper slope: From late 2001 onward, this phase was characterized by the intense exploitation of the two main latitudinal strata, lat. 23[degrees]S-25[degrees]S and lat. 26[degrees]S-29[degrees]S, between the 250 and 450 m isobaths (Fig. 3A, 3B). The trawler Insung 207 which initiated this second phase was joined later by six trawlers, mostly Spanish. Operations directed to the northern and southern latitudinal strata were associated with commercial concentrations of the Argentine hake and the Argentine shortfin squid, respectively. Except for Insung 207, all vessels cited above terminated their operations off Brazil during 2002 (Fig. 1).
Directed phase of the lower slope: Initiated in early 2002, this phase was directed at concentrations of deep-sea shrimps. In 2002 the trawler Nuevo Apenino conducted exploratory tows deeper than 700 m obtaining, north of lat. 25[degrees]S, the first commercial catches of the "carabinero" or scarlet shrimp, Aristaeopsis edwardsiana. By late 2002 two other trawlers initiated the directed exploitation of this species as well as the "moruno" or giant red shrimp, Aristaeomorpha foliacea, and "alistado" shrimp, Aristeus antillensis, between lat. 24[degrees]S and lat. 25[degrees]S and the 700-800 m isobaths (Fig. 3A, 3B). After 2002 this fishery expanded with the entry of new chartered vessels and the identification of new fishing grounds north of lat. 19[degrees]S (Pezzuto et al., 2006b).
[FIGURE 3 OMITTED]
The trawlers Mar Maria and Insung 207 also operated in the northern and northeastern sectors of Brazilian coast. These operations were distributed on a wide longitudinal range concentrating within long. 35[degrees]W and long. 38[degrees]W (Fig. 2A). Nearly 100 tows were conducted close to the northern boundary of the Brazilian EEZ (long. 48[degrees]W-51[degrees]W) on depths from 400 to 1,200 m, where moderate catches of deep-sea shrimp were obtained. Operations of Mar Maria also concentrated on the flat tops of seamounts that compose the Ceara Plateau and the Fernando de Noronha Chain (Fig. 2A). These seamounts elevate from nearly 1,000 m depths, at their base, to 200 m depths at the top, where the gentle topography was found to be suitable for trawling. Catches in these areas were mostly composed of the black grouper, Epinephelus nigritus, whose catch rates decreased rapidly to unprofitable levels forcing this trawler to move to southern Brazil and join the deep-sea shrimp fishery.
Catches and Targets
The chartered trawlers produced altogether 8,075 t of retained catch and 6,480 t of processed products destined for international markets (Table 1, 4). Nearly 70% of the total retained catch was composed of the Argentine hake (41.1%) and the Argentine shortfin squid (28.6%) (Table 4). The bone fishes silver John dory, monkfish, Brazilian codling, and black grouper composed together 23% of the total retained catch. Deep-sea shrimps (family Aristeidae) and other bony and cartilaginous fish composed the remaining 7.2%.
Annual production peaked at 5,000 t in 2002 when nine trawlers were operating simultaneously in Brazilian waters (Fig. 4A). The bulk of this production was composed of massive catches of Argentine hake and Argentine shortfin squid (Fig. 4B). The trawler Insung 207 produced the largest overall catch. This trawler not only conducted the greatest number of trips during the study period but also obtained, in 2002, the largest Argentine shortfin squid catch ever recorded in Brazilian waters (1,241 t in three fishing trips in July-September 2002). In all the other years the Argentine hake was the most abundant species in the catch (Fig. 4B).
The main catch components during the study period were principally caught in the area delimited by lat. 23[degrees]S and lat. 25[degrees]S (Fig. 5A). An exception was the Argentine shortfin squid whose catches concentrated further south between lat. 26[degrees]S and lat. 30[degrees]S. Also it is worth noting that the Brazilian codling was the only retained species caught throughout the entire latitudinal range whereas the deep-sea shrimps were restricted to northernmost areas (Fig. 5A). Chartered fleet operations also obtained most of their catch in the 300-500 m depth stratum with the exception of the deep-sea shrimps that were caught in depths of 700 m on average (Fig. 5B). All species were caught throughout the 24-h period, but the Argentine short-fin squid and the Argentine hake were mostly caught during daytime whereas catches of the silver John dory and the monkfish tended to be larger between 1200 h and 2400 h (Fig. 5C).
Slope trawling off northern and northeastern Brazil had deep-sea shrimps and the black grouper as the main targets, respectively, the latter composing over 90% of retained catch. Off southeastern and southern Brazil the six most abundant components of the retained catches were initially regarded as potential targets of chartered trawlers during the studied period.
The analysis of targets in multispecies fisheries, as proposed by Biseau (1988), enabled the characterization of three types of cumulative frequency distribution curves of the catches (Fig. 6). These curves were used to define criteria for the classification of the species into three categories: incidental, target-species, and massive target species (Table 5). Following these criteria, cumulative curves built for all six species were analyzed considering all recorded tows and tows pooled by trawler, trimester, latitudinal and bathymetric strata (Table 6).
The Brazilian codling was generally classified as an incidental species (Fig. 6) for all chartered trawlers, where the species rarely contributed more than 20% of the retained catch (Table 6). The same was observed in most trimesters and in latitudinal and bathymetric strata. Exceptions to this pattern were found in tows south of lat. 29[degrees]S and during the end of 2000, when the species may have been included in the role of the targets during the trawling exploratory phase (Table 6).
The monkfish was classified as a target species in general terms but such classification was not homogeneous among trawlers (Fig. 6, Table 6). Furthermore the species was incidental during most of the analyzed period, but during the second trimesters of 2001, 2002, and 2003 it oscillated between target species and massive target species. The same was observed in areas deeper than 600 m (Table 6).
The Argentine shortfin squid, the Argentine hake, the silver John dory and the deep-sea shrimps (here analyzed as one single category) were classified as massive target species which means that they constituted targets of highly directed effort and/or occurred in such dense mono-specific concentrations in nature as to contribute to the largest part of the catch obtained by each tow (Fig. 6). In all species, however, that classification was not homogeneous among trawlers (Table 6). Furthermore, the exploitation of the Argentine hake and the Argentine shortfin squid as massive targets was restricted to the period between late 2001 and early 2003, in the former species, and to the winter seasons, south of lat. 25[degrees]S and between 200-600 m depths in the latter species (Table 6). The silver John dory was classified as a massive target species in several fishing seasons, all latitudinal strata, and in areas shallower than 400 m (Table 6).
[FIGURE 4 OMITTED]
Deep-sea shrimps were a target species in the tows conducted by the trawler Nuevo Apenino who produced the first commercial catches of these species off southeastern Brazil. The trawlers Costa Grande and Mar Maria, on the other hand, directed their operations to these shrimps where they were classified as a massive target species (Table 6). Such conditions were observed from late 2002 onwards, as these vessels initiated their operations in Brazilian waters, north of lat. 25[degrees]S and deeper than 600 m (Table 6).
In the southern and southeastern sectors of Brazilian coast total retained catch rates were, on average, 123,012.2 kg/trip ([+ or -] 15,384.1 kg/trip SE) and 368.9 kg/h ([+ or -] 11.5 kg/h SE) (Tables 7, 8). These rates increased in 2001-02 (394-489 kg/h) during the upper slope directed phase (targeting the Argentine hake and the Argentine shortfin squid) and decreased almost 60% in 2003, when the lower slope directed phase aiming at the deep-sea shrimps was established (Table 8). Mean catch rates were highest in the shallowest and southernmost strata and tended to decrease toward deep northern grounds (Fig. 7). Mean catch rates in northern and northeastern Brazil, were 39,729.6 kg/trip ([+ or -] 13,033.5 kg/trip SE) and 107.2 kg/h ([+ or -] 3.9 kg/h SE) (Tables 7, 8).
The Argentine hake and the Argentine shortfin squid were the most productive targets of the chartered slope trawling off Brazil reaching, on average, over 100 kg/h (Table 8). The former species was most productive in 2001 and 2002 when mean catch rates oscillated between 171.3-183.3 kg/h. In 2003 catch rates dropped sharply to nearly 30% of the previous levels. The Argentine shortfin squid, on the other hand, had one sporadic fishing episode in mid 2002 when catch rates of one particular trawler averaged nearly 200 kg/h (Table 8). Aside from that episode, mean catch rates varied between 16 and 48 kg/h. Monkfish catch rates were also superior in 2001 and 2002, although interannual variability was not as pronounced as in the case of the Argentine hake. The silver John dory and the Brazilian codling were not permanent targets of the chartered fleet, and therefore the retained catches may not have been related with their availability on the slope fishing grounds. However, the elevated catch rates of the silver John dory between 2001 and 2003 were noticeable (Table 8). In general, all catch rates declined in 2003 except for those recorded for the deep-sea shrimps (Table 8). In essence that reflects the reduction of the chartered fleet that year and the intensification of trawling in the lower slope grounds where most of the fish and squid targets are not abundant.
[FIGURE 5 OMITTED]
The Argentine hake and Argentine shortfin squid catch rates were slightly highest at depths shallower than 200 m and tended to decrease toward deeper grounds being totally absent in areas deeper than 600 m (Fig. 7A). Latitudinally, however, both species exhibited inversed distribution patterns with Argentine hake and Argentine shortfin squid catch rates being largest in the northern and southern sectors, respectively (Fig. 7B). Whereas the monkfish catch rate distribution was relatively homogeneous in all depth and latitudinal strata, silver John dory catch was scarce in areas deeper than 400 m and in all latitudinal strata (Fig. 7). Deep-sea shrimps catch rates were only available for the lower 600 m areas of the northern sector (Fig. 7).
Chartered trawlers operated in the Brazilian slope following patterns in many ways similar to the ones exhibited during the development of deep-water trawling in the North Atlantic, which involved both exploratory and specialized phases in association with different trawler types (Iglesias and Paz, 1995; Charuau et al., 1995; Gordon, 2001). Off Brazil, the process was pioneered in late 2000-early 2001 by two large vessels that covered broad latitudinal areas and a variety of habitats. These vessels obtained some of the first profitable catches of resources previously considered as either unproductive or uneconomical, aside from delimiting their main slope fishing grounds (Perez et al., 2003; Haimovici, 2007).
[FIGURE 6 OMITTED]
This exploratory phase was shortly followed by the entry of Spanish trawlers highly focused on Argentine hake production in the southeastern sector of the Brazilian slope. Previously operating off northwest Africa, such vessels were smaller, highly efficient, and able not only to fully exploit the hake concentrations 300-400 m deep but also to occasionally explore the deep slope for new opportunities. By the end of 2002, as international markets for hake caught off Brazil became no longer favorable, most vessels abandoned Brazilian waters.
In association with the end of the directed phase, however, a) a "national" trawl fishery consolidated on the upper slope grounds off southeastern Brazil aiming at hake and other species mostly for the domestic market (Perez and Pezzuto, 2006), and b) a new phase directed towards valuable aristeid shrimps began from the subsequent operations of two remaining Spanish trawlers. This justified the continuation of the chartering program and the onset of a new lower slope trawl fishing phase (Pezzuto et al., 2006b).
In northern and northeastern Brazilian waters, chartered trawling led to less promising perspectives. First, another potential fishing ground for aristeid shrimps was detected off the northern State of Amapa, possibly associated with stocks already exploited in the French Guiana EEZ (Gueguen, 2000; Pezzuto et al., 2006b). Unlike the trawlers in the neighboring country, these grounds have not attracted the Brazilian trawl fleet that is strongly focused on the coastal pink shrimp, Farfantepenaeus subtilis, production (Aragao et al., 2004). As for chartered trawlers, the area was not considered a priority due to operational difficulties, as imposed by strong bottom currents and deep fine sediment layers. Secondly, the chartered fleet produced a brief and unprecedented trawl fishing episode on the flat tops of some seamounts off northeastern Brazil, which exploited to exhaustion dense concentrations of the black grouper. Both scientists and fishing authorities reaction to the analysis of this episode was to recommend the closure of these seamounts for trawl fishing and include them on the list of potential Marine Protected Areas of the Brazilian coast (Anonymous, 2006)
Brazilian slope trawling until 2003 concentrated on the so-called "permanent residents of the upper 400 m" (Gordon et al., 1995; Gordon, 2005) composed of species more closely related to shelf dwellers than true deep-sea forms (Merret and Haedrich, 1997). Off southeastern and southern Brazil, these targets were amongst the dominant species of the upper slope area (100-500 m) as shown by trawl surveys conducted in 2001-02 (Haimovici et al., 2006b). These surveys also showed the silver John dory, Argentine hake, Brazilian codling, monkfish, and Argentine shortfin squid particularly concentrated on the 300-500 m depth stratum where both chartered and national trawlers overlapped and obtained their most productive catches between 2000 and 2003 (Perez and Pezzuto, 2006). Latitudinally, catch patterns of the chartered fleet also coincided with those shown by the national trawlers and the trawl surveys including, for example, the well-known concentration of Argentine hake and the gulf hake in the northern and southern extremes of the fishing area respectively (Perez and Pezzuto, 2006; Haimovici et al., 2006b). Whereas landings composition corroborated such spatial exploration pattern, existing differences between national and chartered fleets could be related, however, to the national/international market preferences aimed by these fleets respectively (Perez et al., 2002a; Perez et al., 2003; Perez and Pezzuto, 2006). Thus the abundant gulf hake has been a major target of national but not chartered trawlers, and the silver John dory and Argentine squid has been mostly retained (and exported) by chartered vessels. These differences further implied in particular (although not yet empirically addressed) discard practices involving the above mentioned and other abundant slope species including beardfish, Polimixia lowei; Splendid alfonsino, Bervx splendens; Helicolenus lahillei; and Marini's grenadier, Caelorinchus marinii (Haimovici et al., 2006b).
A particular scenario emerged from the establishment of the aristeid shrimp-directed lower slope fishery. Trawling operations in this area have been highly restricted to the most productive 700-800 m depth range and produced significant catches of the deep-sea crabs, Chaceon ramosae (Pezzuto et al., 2006b) as well as a high diversity of truly deep-sea fin-fish (families Synaphobranchidae, Macrouridae, Trachichthyidae, Berycidae, Astronesthidae, Oreosomatidae, lpnopidae, Alepocephalidae, Ophidiidae and others), elasmobranches (families Rajidae, Scyliorhinidae), holocephalids (family Chimaeridae), and cephalopods (family Histioteuthidae, subfamily Bathypolipodinae).I Hitherto none of these bycatch species (some of them commercially exploited elsewhere) have been identified as potential fishing targets, a consequence of either the high profitability of aristeid shrimp catches or inexistent (or still undetected) specific productive grounds. Whereas the next deep-water trawling phase off the Brazilian coast is uncertain, the abundant and diverse by-catch produced by deep-water shrimp trawling, as also described for similar fisheries worldwide (Sartor et al., 2003; D'Onghia et al., 2003), may be a critical aspect to be considered for the future development of this new Brazilian fishery.
Bottom trawling is a traditional fishing practice in Brazil that has sustained a significant proportion of the country's demersal catches in the past 40 years (Haimovici et al., 2006a; Valentini and Pezzuto, 2006). This practice developed as a large-scale industry, after the technological influence of a process of chartering and importing double-rig trawlers from the Gulf of Mexico in the mid 1960's (Valentini et al., 1991). From 2000 onwards, the chartering of foreign vessels reappeared as a mechanism to induce the expansion of such industry into deep-sea areas, a process that involves new paradigms on fishing, processing, and commercializing (Perez et al., 2001; Perez et al., 2003). Unlike the introduced bottom gillnets for monkfish fishing and pots for deep-sea crabs (Wahrlich et al., 2005; Pezzuto et al., 2006a), slope trawling could rapidly become a concrete trend of national fishing owing to the already available fleet and the lower costs involved in setting those new paradigms. In fact, southeastern and southern upper slope occupation by both national and foreign trawlers was virtually simultaneous, the latter being regarded by the former more like unfair competitors than models. The analysis of data generated extensively by observers on board chartered trawlers, however, allowed some important distinctions to be made about the factual role of chartering to the development of slope trawling off Brazil.
Chartered vessels, in comparison with national ones, were larger, powered by stronger engines and with faster winches, could spend a long time at sea and had crews experienced in operations over slope grounds elsewhere in the Atlantic. As explorers, these vessels were able to cover a vast area between the two extremes of the country's EEZ, from 100 to 1,000 m, accomplishing in 2 years more than any research vessel or national trawler had in decades. However, these vessels were market-oriented with elevated profit demands, which made them quickly turn from exploration to exploitation particularly focused on Argentine hake and aristeid shrimps concentrations in southeastern Brazil. Technologically limited, national trawlers, traditionally operating on the shelf and shelf break in that region, were able to expand to the upper slope and compete with foreign trawlers for hake but not for the valuable deep-sea shrimps on deeper areas. In the latter case fishing technology possibly justified chartering, as national trawlers could not easily assess these grounds. In the former case, however, national exploitation of Argentine hake prevailed, possibly because double-rig trawlers were more numerous, efficient, and favored by a more stable and less competitive domestic market (Perez and Pezzuto, 2006).
Another relevant aspect is concerned with the impacts the foreign trawl fleet could have made on slope resources, both individually and in addition to the ones produced by national trawlers. Recent analysis has indicated that annual Argentine hake landings surpassed, between 2001 and 2003, the total recommended catch (2,215 t) and total biomass decreased nearly 50% from 2003 onwards (Anonymous, 2007). Chartered trawlers contributed to 38.4% (1,018.3 t) and 52.7% (1,952.9 t) of the total landings in 2001 and 2002, respectively. In the following year, total catch was maintained at the 3,000 t level, nearly 90% being produced by national vessel operations. Considering that over 160-170 national trawlers contributed annually to those catches between 2001 and 2003 in contrast to six chartered units, it is evident that the latter represented a major impact on the hake stock, and their coexistence with the national fleet would only have reduced the species abundance to more critical levels (Perez and Pezzuto, 2006; Anonymous, 2007). Similar scenarios could be described for the monkfish and the Brazilian codling, although both species were not major targets of trawlers possibly being avoided by the net arrangement in the former case (Perez et al., 2002a) or by exploiting a geographic area where the latter species is not particularly abundant (Haimovici et al., 2006b). Finally, deep-sea shrimp exploitation by chartered trawlers has been characterized by a concentration of effort on relatively restricted areas of the slope where nearly 80% abundance reductions have been estimated between 2003 and 2004 (Pezzuto et al., 2006b; Anonymous, 2007). Whereas complete assessments are still required, it is evident that such valuable resources will accommodate only a few highly controlled vessels (Anonymous, 2007).
In summary, the recent Brazilian chartering program has proven to be an efficient instrument to both explore and exploit deep-sea demersal resources of the country's EEZ. Because of the fragility and generally limited potential yields of these resources (Perez, 2006), however, eventual benefits produced by chartered trawler operations to the national industry can be rapidly cancelled out by important abundance reductions as generated by the intense removals required to match these trawlers' profit demands. Chartering trawlers for deepwater fishing development off Brazil seems no longer viable unless for specific short-term exploratory initiatives in areas deeper than 1,000 m within the country's EEZ or in international waters. Even so this process must be ruled by precaution, intense observation, and control.
[FIGURE 7 OMITTED]
The authors are indebted to all members of the Chartered Fleet Observers Program for their hard work and the quality of collected data. We also thank vessel owners, captains, and crew members of all monitored vessels for the support and good will during the long fishing trips. Rodrigo Claudino dos Santos and Rodrigo Dallagnolo contributed with maps and figures. The Department of Fishery and Aquaculture, Ministry of Agriculture and the Special Secretariat of Aquaculture and Fisheries (Brazilian Government) provided funds for this study through a series of scientific cooperation programs with Vale do Itajai University (MA/ SARC/ 03/ 2000; MAPA/ SARC/ DPA/ 03/ 2001; MAPA/SARC/ DENACOOP/ 176/ 2002; SEAP/ PR/ 001/ 2003; SEAP/ PR/ 078/ 2004; SEAP/ PR/ 064/ 2005).
Anonymous. 2006. Presidencia da Republica. Secretaria Especial de Aquicultura e Pesca. Comite Consultivo Permanente de Gestao dos Recursos Demersais de Profundidade. Sub-Comite Cientifico. Relatorio da 4a Reuniao Ordinaria. Itajai, SC, 3-5 de Maio de 2006, 56 p.
--. 2007. Presidencia da Republica. Secretaria Especial de Aquicultura e Pesca. Comite Consultivo Permanente de Gestao dos Recursos Demersais de Profundidade. SubComite Cientifico. Relatorio da 5a Reuniao Ordinaria. Itajai, SC, 11-13 de junho de 2007, 75 p.
Aragao, J. A. N., I. H. A. Cintra, and K. C. Silva. 2004. Revisao dos dados de esforco de pesca e captura das pescarias de camarao-rosa, Farfantepenaeus subtilis (Perez Farfante, 1967) (Crustacea, Decapoda, Penaeidae) na regiao norte do Brasil. Boletim. Tecnico Cientifico do CEPNOR 4:1-44.
Biseau, A. 1988. Definition of a directed fishing effort in a mixed-species trawl fishery, and its impact on stock assessments. Aquat. Living Resour. 11:119-136.
Charuau, A., H. Dupuoy, and P Lorance. 1995. French exploitation of the deep-water fisheries of the North Atlantic. In A. G. Hooper (Editor), Deep-water fisheries of the North Atlantic oceanic slope, p. 337-356. Kluwer Acad. Publ., Netherl.
D'Onghia, G., F. Mastrototaro, A. Matarese, C.1. Pofitou, and Ch. Mytilenou. 2003. Biodiversity of the upper slope demersal community in the Eastern Mediterranean: Preliminary comparison between two areas with and without trawl fishing. Northw. Ail. Fish Sci. 31:263-273.
Gordon, J. D. 2001. Deep-water fisheries at the Atlantic frontier. Continental Shelf Res., 21:987-1003.
--. 2005. Environmental and biological aspects of deepwater demersal fishes. In R. Shotton (Editor) Deep-sea 2003: Conference on the governance and management of deepsea fisheries. Part 1. Conference reports. 1-5 December 2003. Queenstown, New Zealand. FAO Fish. Proc. 3/1, p. 70-88.
--, N. R. Merret, and R. Haedrich. 1995. Environmental aspects of slope dwelling fishes of the north Atlantic. In A. G. Hooper (Editor), Deep-water fisheries of the North Atlantic oceanic slope, p. 1-26. Kluwer Acad. Publ., Netherl..
--, O. A. Bergstad, I. Figueiredo, and G. Menezes. 2003. Deep-water fisheries of the Northeast Atlantic: I. Description and current trends. J. Northw. Ail. Fish. Sci. 31:137-150.
Gueguen, F. 2000. Distribution et abondance des crustaces decapods du talus continental (200-900 m) de Guyane Fracaise. Crustaceana 73(6): 685-703.
Haimovici, M. (Organizer) 2007. A prospeccao pesqueira e abundancia de estoques marinhos no Brasil nas decadas de 1960 a 1990: levantamento de dados e avaliacao critica. Programa REVIZEE. Avaliacao do Potencial Sustentavel de Recursos Vivos na Zona Economica Exclusiva MMA/ SQA, Ministerio do Meio Ambiente, Brazil, 325 p.
--, M. C. Cergole, R. P. Lessa, L. S. Madureira, S. Jablonski, and C. L. D. B. Rossi-Wongstchowski. 2006a. Capitulo 2. Panorama Nacional. In MMA/SQA Programa REVIZEE: Avaliacao do Potencial Sustentavel de Recursos Vivos na Zona Economica Exclusiva. Relatorio Executivo, p. 79-126. Ministerio do Meio Ambiente, Brazil.
--, C. L. D. B. Rossi-Wongstchowski, M. C. Cergole, L. S. Madureira, and R. A. Berrardes 2006b. Capitulo 6. Recursos pesqueiros da costa Sudeste-Sul. In MMA/SQA. Programa REVIZEE: Avaliacao do Potencial Sustentavel de Recursos Vivos na Zona Economica Exclusiva. Relatorio Executivo, p. 218-254. Ministerio do Meio Ambiente, Brazil.
Iglesias, S., and J. Paz. 1995. Spanish North Atlantic deep-water fisheries. In A. G. Hooper (Editor), Deep-water fisheries of the North Atlantic oceanic slope, p. 287-295. Kluwer Acad. Publ., Netherl..
Lourance, P., and H. Dupuoy. 2001. CPUE abundance indices of the main target species of the French deep-water fishery in ICES Sub-areas V-VII. Fish. Res.. 51:137-149.
Merret, N. R., and R. L. Haedrich. 1997. Deep-sea demersal fish and fisheries. Chapman & Hall, London, UK, 281 p.
Perez, J. A. A. 2006. Potenciais de rendimento dos alvos da pesca de arrasto do talude do sudeste e sul do Brazil estimados a partir de parametros do ciclo de vida. Braz. J. Aquat. Sei. Technol., 10:1-11.
--, and P. R. Pezzuto. 2006. A pesca de arrasto de talude do Sudeste e Sul do Brasil: tendencias da frota nacional entre 2001 e 2003. Bolm. Inst. Pesca, Sao Paulo 32:127150.
--, --, L. F. Rodriguez, H. Valentini, and C. M. Vooren. 2001. Relatorio da reuniao tecnica de ordenamento da pesca demersal nas regioes Sudeste e Sul do Brasil. In P R. Pezzuto, J. A. A. Perez, L. F. Rodriguez, and H. Valentini (Editors), Reunioes de ordenamento da pesca demersal no Sudeste e Sul do Brasil: 2000-2001. Not. Tec. FACIMAR 5:1 34.
--, R. Wahrlich, P. R. Pezzuto, and F. R. A. Lopes. 2002a. Estrutura e dinamica da pescaria do peixe-sapo Lophius gastrophysus no Sudeste e Sul do Brasil. Bolm. Inst. Pesca, Sao Paulo, 28:205-231.
--, P. R. Pezzuto, H. A. Andrade, P. R. Schwingel, M. Rodrigues-Ribeiro, and R. Wahrlich. 2002b. O Ordenamento de uma nova pescaria direcionada ao peixe-sapo (Lophius gastrophysus) no Sudeste e Sul do Brasil. Not. Tec. FAC1MAR 6:65-83.
--, R. Wahrlich, P. R. Pezzuto, P R. Schwingel, F. R. A. Lopes, and M. Rodrigues-Ribeiro. 2003. Deep-sea fishery off Southern Brazil: recent trends of the Brazilian fishing industry. J. Northw. Ad. Fish. Sci. 31:1-18.
--, P. R. Pezzuto, and H. A. Andrade. 2005. Biomass assessment of the monkfish Lophius gastrophysus stock exploited by a new deep-water fishery in southern Brazil. Fish. Res. 72:149-162.
Pezzuto, P. R., J. A. A. Perez, and R. Wahrlich. 2006a. O ordenamento das pescarias de caranguejos-de-profundidade (Chaceon spp) (Decapoda: Geryonidae) no sul do Brasil. Bohn. Inst. Pesca, Sao Paulo 32: 229-240.
--, --, and --. 2006b. Deep-sea shrimps (Decapoda: Aristeidae): new targets of the deep-water trawling fishery in Brazil. Braz. J. Oceanogr. 54:123-134.
Pineiro, C. G., M. Casas, and R. Banon. 2001. The deep-water fisheries exploited by Spanish fleets in the Northeast Atlantic: a review of the current status. Fish. Res. 51:311-320.
Rossi-Wongstchowski, C. L. D. B., J. Valentin, S. Jablonsky, A. C. Z. Amaral, F. H. V. Hazin, and M. El-Robrini. 2006. Capitulo 1. O Ambiente Marinho. In MMA/SQA. Programa REVIZEE: Avaliacao do Potencial Sustentavel de Recursos Vivos na Zona Economica Exclusiva. Relatorio Executivo, p. 21-77, Ministerio do Meio Ambiente, Brazil.
Sartor, P., M. Sbrana, B. Reale, and P. Belcari. 2003. Impact of the deep-sea trawl fishery on demersal communities of the Northern Tyrrenian Sea (Western Mediterranean). J. Northw. Ad. Fish. Sci. 31:275-284.
Troyanovsky, F. M., and S. F. Lisovsky. 1995. Russian (USSR) fisheries research in deep-waters (below 500 m) in the North Atlantic. In A. G. Hooper (Editor), Deep-water fisheries of the North Atlantic oceanic slope, p. 357-365. Kluwer Acad. Publ., Netherl.
Wahrlich, R., J. A. A. Perez, and F. R. A. Lopes. 2005. Aspectos tecnologicos da pesca do peixe-sapo (Lophius gastrophysus) com rede de emalhar no Sudeste e Sul do Brasil. Bohn. Inst. Pesca, Sao Paulo 30:87-98.
Valentini, H., F. D'Incao, L. F. Rodrigues, J. E. Rebelo Neto, and E. Rahn. 1991. Analise da pesca do camarao-rosa (Penaeus paulensis e Penaeus brasiliensis) nas regioes Sudeste e Sul do Brasil. Atlantica, Rio Grande 13:171-177.
--and P. R. Pezzuto. 2006. Analise das principais pescarias comerciais da regiao Sudeste-Sul do Brasil com base na producao controlada do periodo 1986-2004. In C. L. D. B. Rossi- Wongstchowski (Editor), Serie Documentos REVIZEE: Score-Sul, 56 p., Instituto Oceanografico, Universidade de Sao Paulo, Brazil.
The authors are with Centro de Ciencias Tecnologicas da Terra e do Mar-CTTMar, Universidade do Vale do Itajai-UNIVALI, Cx. Postal 360, Itajai, Santa Catarina, Brazil CEP 88302202 (email: firstname.lastname@example.org).
(1) Perez, J. A. A. Centro de Ciencias Tecnologicas da Terra e do Mar--CTTMar, Universidade do Vale do Itajai-UNIVALI, Cx. Postal 360, Itajai, Santa Catarina, Brazil CEP 88302-202. Personal commun., 2008.
Table 1.--Summary of fishing trips conducted by chartered trawlers in Brazilian waters between October 2000 and October 2003. Beginning of End of Vessel operations operations Joana 10/26/00 01/22/01 Insung 207 05/23/01 07/25/03 Rio Bouzos Uno 10/22/01 06/27/02 Cipi 10/04/01 02/13/02 Nuevo Apenino 09/17/01 07/30/02 Hermanos Vaqueros 11/13/01 06/13/02 Emanguluko 12/13/01 04/01/02 Arneles 01/23/02 01/11/02 Costa Grande 04/03/02 07/31/03 Mar Maria 08/22/02 10/20/03 Total/range Vessel Latitude range Joana 23[degrees]38'S-34[degrees]02'S Insung 207 03[degrees]15'S-34[degrees]36'S Rio Bouzos Uno 23[degrees]26'S-27[degrees]11'S Cipi 23[degrees]23'S-33[degrees]05'S Nuevo Apenino 23[degrees]00'S-32[degrees]50'S Hermanos Vaqueros 23[degrees]08'S-28[degrees]05'S Emanguluko 19[degrees]51'S-33[degrees]05'S Arneles 24[degrees]01'S-31[degrees]28'S Costa Grande 23[degrees]05'S-27[degrees]08'S Mar Maria 08[degrees]14'N-27[degrees]38'S Total/range 08[degrees]14'N-34[degrees]36'S Vessel Longitude range Joana 41[degrees]53'W-51[degrees]35'W Insung 207 40[degrees]O2'W-54[degrees]29'W Rio Bouzos Uno 41[degrees]10'W-47[degrees]03'W Cipi 41[degrees]04'W-5O[degrees]28'W Nuevo Apenino 41[degrees]01'W-50[degrees]23'W Hermanos Vaqueros 40[degrees]10'W-48[degrees]58'W Emanguluko 38[degrees]02'W-50[degrees]28'W Arneles 43[degrees]06'W-49[degrees]46'W Costa Grande 41[degrees]12'W-46[degrees]52'W Mar Maria 34[degrees]25'W-50[degrees]31'W Total/range 34[degrees]25'W-54[degrees]29'W Depth Number Number Vessel range (m) of trips of tows Joana 131-460 2 300 Insung 207 75-720 14 2,559 Rio Bouzos Uno 118-468 5 708 Cipi 224-492 3 437 Nuevo Apenino 124-795 9 932 Hermanos Vaqueros 190-1,173 5 510 Emanguluko 60-920 3 244 Arneles 129-394 1 18 Costa Grande 220-762 10 1,742 Mar Maria 203-1,158 7 1,619 Total/range 60-1,173 59 9,069 Trawled by trip production Vessel hours (min-max) (t) Joana 1,132.3 118.1-141.7 259.8 Insung 207 5,707.9 83.9-421.3 3,955.5 Rio Bouzos Uno 2,111.8 73.6-81.8 380.5 Cipi 1,326.7 79.1-98.3 272.7 Nuevo Apenino 3,474.3 32.4-80.5 528.2 Hermanos Vaqueros 2,244.5 37.4-63.1 204.2 Emanguluko 452.4 39.0-81.4 168.3 Arneles 70.7 7.7 7.7 Costa Grande 7,173.5 11.5-63.9 361.1 Mar Maria 6,391.1 12.7-92.2 341.8 Total/range 30,085.2 7.7-421.3 6,479.8 Table 2.--Summary of chartered trawlers that operated off Brazil from October 2000 to October 2003 including their flag country and their main features. Flag Year of Total length Vessel country construction (m) Joana Portugal 60.00 Insung 207 South Korea 1975 56.90 Rio Bouzos Uno Spain 1986 33.00 Cipi Spain 1973 39.00 Nuevo Apenino Spain 1998 33.00 Hermanos Vaqueros Spain 1969 27.80 Emanguluko Namibia 1989 31.10 Arneles Spain 1984 75.70 Costa Grande Spain 1973 30.00 Mar Maria Spain 1998 38.40 Vessel Engine power GT Storing capacity (h p) (t) (t) Joana Insung 207 1,700 890 320 Rio Bouzos Uno 2,200 925 350 Cipi 1,200 324 80 Nuevo Apenino 870 270 110 Hermanos Vaqueros 1,000 200 145 Emanguluko 490 168 75 Arneles 1,900 483 100 Costa Grande 1,850 789 692 Mar Maria 800 170 80 1,200 271 140 Vessel Autonomy Crew (days-at-sea) (workers) Joana Insung 207 70 32 Rio Bouzos Uno 50 41 Cipi 80 18 Nuevo Apenino 70 19 Hermanos Vaqueros 60 18 Emanguluko 50 18 Arneles 24 28 Costa Grande 120 30 Mar Maria 50 16 80 20 Table 3.--Physical features of the fishing gear used by chartered trawlers off Brazil from October 2000 to October 2003 Head rope Ground rope length length Use of Vessel (m) (m) bobbins Joana 37.0-56.0 18-70 Frequent Insung 207 40.0-90.0 55-100 Frequent Rio Bouzos Uno 58.0-65.0 60-80 Frequent Cipi 58.5-67.2 70-80 Occasional NuevoApenino 33.0-85.0 45-100 Occasional Hermanos Vaqueros 65.4-67.0 80 Emanguluko 38.0-80.0 62-95 Frequent Arneles 92.0 110 Frequent Costa Grande 45.0-101.0 47-120 Mar Maria 40.0-71.0 41-85 Occasional Trawl vertical Mesh size Door opening at cod end weight Vessel (m) (mm) (kg) Joana 3.5-4.5 135 1,250 Insung 207 3.5-7.0 70-110 1,600-2,500 Rio Bouzos Uno 3.00 65-70 750-800 Cipi 10.0-15.0 60-85 620 NuevoApenino 2.0-5.0 50-90 900-1,000 Hermanos Vaqueros 3.0-10.0 70 500 Emanguluko 2.0-5.0 70-120 1,600 Arneles 4.00 100 1,600 Costa Grande 1.0-2.5 50-80 500-650 Mar Maria 2.2-3.0 80 900 Table 4.--Catch in tons (t) retained by the chartered trawlers off Brazil from October 2000 to October 2003. Numbers in parentheses represent percentages of the total retained catch of each vessel. Argentine shorffin squid, Illex argentinus; Argentine hake, Merluccius hubbsi; silver John dory, Zenopsis conchifera; monkfish, Lophius gastrophysus; Brazilian codling, Urophycis mystacea; black grouper, Epinephelus nigritus; deep-sea shrimps, family Aristeidae; and other bony and cartilaginous fish. Argentine Argentine Silver Vessel shortfin squid hake John dory Joana 56.9 47.5 124.9 (21.1) (17.6) (46.3) Insung 207 1,830.7 1,657.9 420.1 (41.1) (37.3) (9.4) Rio Bouzos Uno 83.9 348.5 13.7 (16.0) (66.5) (2.6) Cipi 41.6 270.6 27.7 (10.6) (68.7) (7.0) Nuevo Apenino 74.8 498.0 36.8 (10.2) (68.1) (5.0) Hermanos Vaqueros 13.3 187.1 1.9 (4.3) (60.1) (0.6) Emanguluko 118.1 61.0 37.1 (46.3) (23.9) (14.5) Arneles 1.6 7.3 0.6 (14.8) (68.8) (5.4) Costa Grande 86.0 241.3 11.8 (11.2) (31.4) (1.5) Mar Maria 5.4 3.1 0.0 (1.5) (0.9) (0.0) Total 2,312.3 3,322.3 674.6 (28.6) (41.1) (8.4) Brazilian Black Vessel Monkfish codling grouper Joana 19.1 3.7 0.0 (7.1) (1.4) (0.0) Insung 207 178.5 33.5 0.0 (4.0) (0.8) (0.0) Rio Bouzos Uno 19.0 37.1 0.0 (3.6) (7.1) (0.0) Cipi 30.6 16.9 0.0 (7.8) (4.3) (0.0) Nuevo Apenino 39.5 39.2 0.0 (5.4) (5.4) (0.0) Hermanos Vaqueros 61.5 27.7 0.0 (19.8) (8.9) (0.0) Emanguluko 31.4 3.6 0.0 (12.3) (1.4) (0.0) Arneles 0.2 0.0 0.0 (1.8) (0.0) (0.0) Costa Grande 327.7 13.6 0.0 (42.7) (1.8) (0.0) Mar Maria 4.5 1.1 293.1 (1.2) (0.3) (81.2) Total 712.0 176.4 293.1 (8.8) (2.2) (3.6) Deep-sea Vessel shrimp Others Total Joana 0.0 17.6 269.7 (0.0) (6.5) Insung 207 0.0 329.5 4,450.2 (0.0) (7.4) Rio Bouzos Uno 0.0 22.1 524.3 (0.0) (4.2) Cipi 0.0 6.6 394.0 (0.0) (1.7) Nuevo Apenino 0.6 42.2 731.1 (0.1) (5.8) Hermanos Vaqueros 0.0 19.9 311.4 (0.0) (6.4) Emanguluko 0.0 3.8 255.0 (0.0) (1.5) Arneles 0.0 1.0 10.7 (0.0) (9.2) Costa Grande 41.4 45.5 767.3 (5.4) (5.9) Mar Maria 34.2 19.6 361.0 (9.5) (5.4) Total 76.2 507.8 8,074.6 (0.9) (6.3) Table 5.--Criteria for classification of the species caught by the chartered trawlers fleet operating off Brazil into target categories adapted from Biseau (1988). Species Definition Incidental Species not subject to directed effort but retained due to its commercial value Target species Species subject to directed effort Massive target Species subject to directed effort whose species distribution is extremely gregarious and that are caught in large quantities without abundant bycatch Species Criteria Incidental More that 40% of the species total retained biomass originated from tows where the species represented less than 20% (QL) of the retained biomass Target species Between 30 and 60% of the species total retained biomass originated from tows where the species represented more than 40% (QL) of the retained biomass Massive target More than 60% of the species total retained species biomass originated from tows where the species represented more than 40% (QL) of the retained biomass Table 6.--Analysis of the targets of the chartered trawler fleet operating off Brazil from October 2000 to October 2003 according to criteria defined in Table 5. White areas refer to species not present in the catches. (a) Massive target species (b) Target species (c) Incidental species Argentine Argentine shortlin Vessel hake squid Monkish Joana (b) (a) (c) Insung 207 (a) (a) (c) Rio Bouzos Uno (a) (b) (c) Cipi (a) (c) (c) Nuevo Apenino (a) (b) (c) Hermanos Vaqueros (a) (c) (b) Emanguluko (b) (a) (c) Arneles (a) (c) (c) Costa Grande (a) (c) (a) Mar Maria (b) (b) (a) Trimester IV.2000 (c) (a) (c) I.2001 (b) (a) (c) II.2001 (c) (c) (b) III.2001 (a) (a) (c) IV.2001 (a) (b) (c) I.2002 (a) (b) (c) II.2002 (a) (b) (a) III.2002 (a) (a) (c) IV.2002 (a) (b) (c) I.2003 (a) (b) (c) II.2003 (a) (a) (b) III.2003 (b) (b) (c) IV.2003 (c) Latitudinal strata 21[degrees]-25[degrees]S (a) (b) (b) 25[degrees]-29[degrees]S (a) (a) (c) 29[degrees]-34[degrees]S (b) (a) (c) Depth strata <200 m (a) (a) (c) 200-400 m (a) (a) (b) 400-600 m (a) (a) (b) >600 m (a) (b) (a) Silver John Brazilian Deep-sea Vessel dory codling shrimps Joana (a) (c) Insung 207 (a) (c) Rio Bouzos Uno (c) (c) Cipi (c) (c) Nuevo Apenino (b) (c) (b) Hermanos Vaqueros (c) (c) Emanguluko (b) (c) Arneles (c) (c) Costa Grande (c) (c) (a) Mar Maria (c) (c) (a) Trimester IV.2000 (a) (b) I.2001 (a) (c) II.2001 (b) (c) III.2001 (a) (c) IV.2001 (a) (c) I.2002 (b) (c) II.2002 (a) (c) (b) III.2002 (b) (c) (b) IV.2002 (b) (c) (a) I.2003 (c) (c) (a) II.2003 (a) (b) (b) III.2003 (a) (a) IV.2003 (a) Latitudinal strata 21[degrees]-25[degrees]S (a) (c) (a) 25[degrees]-29[degrees]S (a) (c) (c) 29[degrees]-34[degrees]S (a) (b) Depth strata <200 m (a) (c) (c) 200-400 m (a) (c) (c) 400-600 m (b) (c) (b) >600 m (c) (c) (a) Table 7.--Total retained catch rates (kg/trip) obtained by the chartered trawl fishery on slope grounds off Brazil between 2000 and 2003. The number of trips is presented in the first row followed by the mean catch rate (x SE) and the maximum value in parentheses. SE S, southeastern and southern sectors; N-NE, northern and northeastern sectors. Year SE-S 2000 2 62,488.8 -120,877.4 2001 16 124,039.5 t 20,625.5 -300,980.60 2002 33 145,540.7 [+ or -] 25,607.3 -516,508.20 2003 11 70,689.2 [+ or -] 24,221.2 -257,104.20 Total 62 123,012.2 [+ or -] 15,384.1 -516,508.20 Year N-NE 2000 2001 2002 3 38,624.8 [+ or -] 15,065.3 -55,035.00 2003 5 40,392.6 [+ or -] 20,180.8 -92,156.60 Total 8 39,729.6 [+ or -] 13,033.5 -92,156.60 Table 8.--Total retained catch rates (kg/h) of the main fishing targets obtained by the chartered trawl fishery on slope grounds off Southeastern-Southern and Northeastern-Northern Brazil between 2000 and 2003. The number of tows is presented in the first row followed by the mean catch rate (x SE) and the maximum value in parentheses. Species 2000 2001 Southeast-South Argentine hake 224 1,955 20.0 [+ or -] 4.2 183.3 [+ or -] 8.3 (497.2) (6,232.9) Argentine 224 1,955 shortfin squid 48.2 [+ or -] 14.8 27.3 [+ or -] 2.9 (1,992.9) (2,473.0) Silver John dory 224 1,955 105.7 [+ or -] 18.8 110.2 [+ or -] 9.7 (1,944.9) (7,634.7) Monkfish 224 1,955 12.5 [+ or -] 1.9 27.7 [+ or -] 1.1 (165.9) (859.3) Brazilian codling 224 1,955 5.2 [+ or -] 2.1 12.0 [+ or -] 0.6 (386.9) (805.4) Deep-sea shrimp Total 224 1,952 183.2 [+ or -]25.1 394.5 [+ or -] 13.6 (2,145.0) (7,736.0) Northeast-North Black grouper Deep-sea shrimp Total Species 2002 2003 Southeast-South Argentine hake 4,044 2,736 171.3 [+ or -] 7.9 58.0 [+ or -] 4.7 (9,978.0) (3,601.0) Argentine 4,046 2,736 shortfin squid 199.4 [+ or -] 19.1 16.0 [+ or -] 1.8 (48,750.0) (2,545.9) Silver John dory 4,046 2,736 340.4 [+ or -] 8.9 25.6 [+ or -] 4.5 (10,765.8) (8,570.0) Monkfish 4,046 2,736 29.3 [+ or -] 2.7 11.9 [+ or -] 1.0 (2,914.2) (336.0) Brazilian codling 4,046 2,736 9.6 [+ or -] 0.4 2.6 [+ or -] 0.3 (952.4) (656.0) Deep-sea shrimp 4,046 2,736 0.9 [+ or -] 0.1 22.6 [+ or -] 1.3 (60.0) (695.2) Total 3,545 2,134 489.4 [+ or -] 23.6 159.9 [+ or -] 8.9 (48,750.0) (6,837.0) Northeast-North Black grouper 497 601 74.8 [+ or -] 5.9 102.8 [+ or -] 4.9 (1,280.0) (695.2) Deep-sea shrimp 497 601 0.47 [+ or -] 0.07 0.03 [+ or -] 0.02 (12.2) (5.3) Total 497 601 86.4 [+ or -] 6.1 124.4 [+ or -] 4.9 (1.280.01 (820.01 Species Total Southeast-South Argentine hake 8,997 135.0 [+ or -] 4.3 (9,978.0) Argentine 8,999 shortfin squid 101.6 [+ or -] 8.7 (48,750.0) Silver John dory 8,999 40.7 [+ or -] 2.6 (10,765.8) Monkfish 8,999 23.1 [+ or -] 1.2 (2,914.2) Brazilian codling 8,999 7.8 [+ or -] 0.2 (952.4) Deep-sea shrimp 8,999 2.0 [+ or -] 0.1 (60.0) Total 7,893 368.9 [+ or -] 11.5 (48,750.0) Northeast-North Black grouper 1,089 90.1 [+ or -] 3.8 (1,280.0) Deep-sea shrimp 1,089 0.23 [+ or -] 0.03 (12.2) Total 1,089 107.2 [+ or -] 3.9 (1.280.01
|Gale Copyright:||Copyright 2009 Gale, Cengage Learning. All rights reserved.|