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Cephalopod Resources of Venezuela

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Cephalopod Resources of Venezuela Cephalopod Resources of Venezuela FREDDY AROCHA Introduction pus have become highly esteemed in Table 1.-Commercial and potentially commercial the local Venezuelan markets, which cephalopods In Venezuelan waters. The cephalopods in the Western in tum has lead to an increase in de­ Local English common common Central Atlantic (FAa area 31) are an mand with corresponding economic Scientific name name name underdeveloped fishery resource. This consequences, i.e., cephalopods be­ Neritic squids is largely due to the present low com­ coming, along with shrimp, a highly Doryteu/his plei Arrow squid Luria mercial value of Venezuelan cephalo­ profitable product. Consequently, Loligo pealei Longtin squid Luria LoNgo surinamensis Surinam squid Luria pods on the world market and the low shrimpers have begun to look at ceph­ Lolliguncula brevis Brief squid Chipiron alopods with a more commercial inter­ Sepio/eu/his local appeal of cephalopods in the diet sepioidea Caribbean reef squid Chopo of Venezuelans. est. Oceanic squids In recent years however, the ceph­ Few studies have been devoted to lIIex coindetti Southern shorttin squid Pota alopod landings have increased the knowledge of cephalopods in Ven­ Ommas/rephes steadily throughout Area 31 (FAa, ezuelan waters. There were some com­ pteropus Orange-back squid Calamar 1987). ments on octopus and squid production Octopods Octopus vulgaris Octopus Pulpo According to FAa statistics for in the late 1960's (Voss, 1971, 1973) 1985 (FAa, 1987), the major cephalo­ but without details on the species pod producing nations in the Western fished. Arocha and Urosa (1982) stu­ fishery. All observations were made Central Atlantic are Mexico and Ven­ died the seven octopus species com­ by the writer, unless otherwise stated. ezuela. While Venezuela has the lead mon to the northeastern coast and Resources of the Area in squid landings, consisting mainly of commented on the fishery for Octopus the arrow squid, Doryteuthis plei, vulgaris. Later, Arocha (1986) studied Twenty-two species of cephalopods Mexico leads the region in production several aspects of the biology of Dory­ are reported from Venezuela (Arocha of octopus (mainly Octopus maya). In teuthis plei, Loligo pealei, and Lolli­ and Urosa, 1982, 1985). Among Venezuela, both squid and octopus are guncula brevis and the commercial these, five species are fished commer­ produced as a by-catch of the shrimp cephalopod fishery in northeastern cially (Table 1). Information on the fishery. Only Mexico has a directed Venezuelan waters. Other studies re­ commercially important species was fishery for octopus. late to the culture and reproductive given by Gines (1972, 1982), who re­ In the past 10 years, squid and octo- biology of noncommercial species, ported on three of the five commercial such as Octopus briareus and Sepio­ species (Doryteuthis plei, Loligo teuthis sepioidea (Robaina, 1983 and pealei, and Octopus vulgaris) and Robaina and Voglar, 1986). Most of summarized the available information ABSTRACT-The cephalopod resources our knowledge of Venezuelan ceph­ on cephalopod landings from shrimp of Venezuela are reviewed, based on pre­ alopods is restricted to the northeastern trawlers of two of the major fishing vious literature and observations from coast. However, there are unpublished areas of Venezuela (Fig. 1), the Gulf commercial catches. The history of the squid and octopus fishery in the majorfish­ data available t on the cephalopod re­ of Venezuela and the northeastern ing grounds is presented along with infor­ sources from the rest of Venezuela. coast from north of Tacarigua Lagoon mation on the catches and seasonality. This study is an attempt to evaluate the to northeast of the Orinoco Delta. This Squids are landed in Venezuela throughout state of the cephalopod resources in latter region is divided into three sub­ the year, with a high in February when Venezuela and adjacent waters as an most of the catch consists of the arrow areas according to its landing ports. squid, Doryteuthis plei. Octopus, Octopus aid to the further development of the The main subarea is around Margarita vulgaris, is abundant in the catches from June until October, with a peak in August­ IThe data used in this report are derived from September. Methods of handling, process­ various sources, although originating basically Freddy Arocha is with the Instituto Oceanog­ ing, and marketing the cephalopod catch from the Direccion General de Desarrollo grafico, Departamento de Biologia Pesquera, Pesquero del Ministerio de Agricultura y Cria of Universidad de Oriente, Apartado 204, Cumana are discussed, and correctional guidelines Venezuela. The original sources came from ves­ 6101, Venezuela. Views or opinions expressed are given. At present, the fishery is in dis­ sel logs, fish companies, and sales agents, and or implied are those of the author and do not array and there is an urgent needfor study thus caution should be observed in its evaluation necessarily reflect the position of the National of Venezuela's commercial cephalopods. and use. Marine Fisheries Service, NOAA. 51(2), 1989 47 72' 71' 70' 69' 68' 67' 66' 65' 64' 63' 62' 61' CAR I 8 8 E A N SE A 12' 12' II' 1000 ------. II' 10' VENEZUELA 72' 71' 70' 69' 68' 67' 66' 65' 64' 63' 62' 61' Figure I.-Major fishing areas: The northwest area (NW) (black area) is in the Gulf of Venezuela and the northeast area (NE) (hatched area) is divided into three subareas: I, Unare-Piritu Lagoon; II, N, E, Margarita Island and III, N, NE of the Orinoco Delta. Depths in meters. Island, followed by the subarea north at night from tuna "baitboats." O. waters, it is occasionally caught north of Unare-Piritu Lagoon and the sub­ pteropus is attracted to the surface by of Los Frailes Island and landed mixed area northeast of the Orinoco Delta, lights and caught with manually oper­ with O. vulgaris. The other species of having as their landing ports Cumana, ated jigs. lllex coindetti is known from octopus reported from Venezuela Guanta, and Giiiria, respectively. Venezuelan waters from only two occur in small numbers, are of rela­ According to later knowledge, some specimens taken east of the Para­ tively small size, and have no com­ of the geographical distributions pre­ guaml Peninsula (Roper et ai., 1969), mercial value. sented by Gines (1972, 1982) are in­ although it is known from unpublished Over 90 percent of the cephalopod complete and inaccurate. It is now data that I. coindetti is common catch of Venezuela is taken by known from unpublished records and throughout the waters of the upper double-rigged trawlers in the shrimp from interviews with fishing company slope of the shelf (200 m) along the fleet. In 1987 the mean yearly catch of officials, that Doryteuthis plei is the Venezuelan coasts. The lower Carib­ squid and octopus made by a trawler most abundant species in the squid bean is thought to be the center of its based at Cumana was 22.8 metric tons landings from the Gulf of Venezuela geographical range in the Western At­ (t) and 10.8 t, respectively (source 2 and, to a lesser extent, Loligo pealei lantic . Thysanoteuthis rhombus is Venepesca). The standard commercial and Lolliguncula brevis. A similar sit­ also known from only two specimens, otter trawl used has a vertical opening uation is found in the northeastern one from the Gulf of Cariaco (Villa, of 3-4 m and a footrope of 29 m. The coast, with the addition of Loligo sur­ 1973) and another fished east of Mar­ main body of the net has a stretched inamensis in the squid catches garita Island (unpubl. data). mesh of 5.2 cm with a stretched mesh (Arocha, 1986). Octopus vulgaris is the only octopus of 4.2 cm in the codend. The trawl is The southern shortfin squid, lllex fished commercially. However, small fished at a constant speed of 2 knots. coindetti, the orange-back squid, Om­ numbers of O. burryi and O. zonatus This method of squid fishing has its mastrephes pteropus, and the rhom­ are mixed with the octopus landings drawbacks because of the low speed at boid squid, Thysanoteuthis rhombus, from the northeastern coast, partic­ which the net is fished and the small are the only oceanic, oegopsid squids ularly from the area around Margarita opening of the net. Thus a substantial known from Venezuelan waters. There Island. Although O. macropus had not improvement in the squid catches is little information on these species, been reported from Venezuelan could be made by increasing the trawl­ except for Ommastrephes pteropus ing speed and the opening of the net. which is known to occur in large num­ The rest of the cephalopod catch is 2Gilbert L. Voss. 1988. Rosenstiel Schuol of bers along the northeastern coast off Marine and Atmospheric Science, University of taken by artisanal fishermen, mainly La Blanquilla Island, where it is fished Miami, Miami, Fla. Personal Commun. along the northeastern and, to a lesser 48 Marine Fisheries Review extent, from the central coasts. The bean, is known only from northeastern be roughly divided into four periods in greater part of the artisanal squid catch Venezuela, particularly northeast of terms of catch. Before 1969, squid (mostly Doryteuthis plei) is taken by the Orinoco Delta and east of Margar­ catches were restricted to the Gulf of hand jigging, while the octopus are ita Island. It contributes a small part of Venezuela where the shrimp fishery caught in traps made of sections of the catch. originated. From then on, part of the used tires, called "Ionganizo." Octopus vulgaris is the largest spe­ trawl fleet moved to new fishing Squid landings from the shrimp cies of octopus common to Venezuela. grounds along the northeastern coast, trawlers consist mainly of Doryteuthis Little is known of the biology of this mainly due to the depletion of the plei from the Gulf of Venezuela, the species in local waters.
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