Spatial and temporal length distribution of Zungaro zungaro caught in the Orinoco River Basin of Colombia

ABSTRACT Objetive. To determine the effect of fishing on capture size of both male and female Zungaro zungaro catfish, historical records of size and spatial distribution of the species were analyzed from the Orinoco Basin in Colombian. Materials and methods. Information was collected by sampling fishing port landings in the region between 1979 and 2011. Each specimen was measured, weighed and sexed. With 5411 records, the average size at capture were compared in time and among the different ports. Size at 50% maturity was estimated by quinquennium. Results. The average commercial capture sizes of Z. zungaro ranged from 35 to 161 cm standard length, with differences between males and females. From 1979 to 2011, in Puerto Lopez, the size at sexual maturity decreased from 123.8 to 83.4 cm in females and from 93.3 to 61 in males. In the annual cycle the greater average capture size in females was from April to July and for males from May to June. Average annual length is higher in the higher parts of the Meta and Guaviare river drainages. In the last quinquennium the size at 50% maturity had fallen 10 cm in females and 5 cm in males and it is higher than the average capture size. Conclusions. Populations of Z. zungaro in the Colombian Orinoco River Basin have been affected by overfishing and selective fishing of females. RESUMEN Objetivo. Determinar el grado de afección en la población de Zungaro zungaro a partir del análisis del comportamiento histórico y espacial de las tallas de captura de hembras y machos de la especie en la Orinoquia colombiana. Materiales y métodos. La información fue colectada mediante muestreos a los desembarcos en puertos pesqueros de la región entre 1979 y 2011. Cada ejemplar fue medido, pesado y sexado. Con 5411 registros, se estableció la distribución de las tallas medias de captura, que se compararon en el tiempo y entre los diferentes puertos. Se estimó la talla de madurez gonadal (TMG) por quinquenios. Resultados. El rango de las tallas de captura comercial Z. zungaro fue de 35 a 161 cm longitud estándar (LS), con diferencia entre machos y hembras. Entre los años 1979 a 2011, en Puerto López, la talla promedio de captura anual (LS) disminuyó de 123.8 a 83.4 cm en hembras y de 93.3 a 61 cm en machos. En el ciclo anual la mayor talla promedio de captura de hembras se presenta en abril a julio y de machos en mayo y junio. La talla promedio de captura anual (TPCA) es superior en las partes altas de los ríos Meta y Guaviare. En el último quinquenio la TMG ha disminuido 10 cm en las hembras y cinco cm en los machos y es superior a la TPCA. Conclusiones. Hay afectación sobre la población explotada de Z. zungaro por sobrepesca por crecimiento y pesca selectiva de hembras en la Orinoquia colombiana

Age and growth of the Amazonian migratory catfish Brachyplatystoma rousseauxii in the Madeira River basin before the construction of dams

The goliath catfish Brachyplatystoma rousseauxii has crucial economical and ecological functions in the Amazon basin. Although its life history characteristics have been studied in the Amazon, there is little information in the Madeira River basin, which holds genetically distinct populations and where dams were recently built. Using fish collected in Bolivia, Brazil and Peru, this study provides a validation of growth rings deposition and details the growth patterns of B. rousseauxii in the Madeira before the dams' construction. Age structure and growth parameters were determined from 497 otolith readings. The species exhibits two growth rings per year and sampled fish were between 0 and 16 years old. In the Brazilian portion of the basin, mainly young individuals below 5 years old were found, whereas older fish (> 5 years) were caught only in the Bolivian and Peruvian stretches, indicating that after migrating upstream to reproduce, adults remain in the headwaters of the Madeira River. Comparing with previous publications, B. rousseauxii had a slower growth and 20 cm lower maximum standard length in the Madeira River than in the Amazon River. This study provides a baseline for future evaluation of changes in population dynamics of the species following dams closure.Santo Antonio Energia (SAE)Universidade Federal de Rondonia (UNIR)Instituto de Estudos e Pesquisas Agroambientais e Organizacoes Sustentaveis (IEPAGRO)CAPES [1402376, 047/2012, 6632/14-9]CNPq [204344/2015-8]Foundation of Support to Research of the Amazon [PAREV/FAPEAM 019/2010]FAPESP (Sao Paulo Research Foundation) [2016/07910-0]Univ Fed Rondonia UNIR, Dept Biol, Lab Ictiol & Pesca, BR 364,Km 9,5, BR-76801059 Porto Velho, RO, BrazilPrograma Posgrad Rede Biodiversidade & Biotechnol, BR 364,Km 9,5, BR-76801059 Porto Velho, RO, BrazilUAGRM, IRD, IIAP, LMI,EDIA, Montpellier, FranceINPA, Av Andre Araujo 2936, BR-69067375 Manaus, AM, BrazilUniv Fed Alagoas UFAL, Av Lourival Melo Mota,S-N Tabuleiro Martins, BR-57072900 Maceio, AL, BrazilUniv Fed Sao Paulo, Rua Doutor Carvalho Mendonca 144, BR-11070100 Santos, SP, BrazilUniv Fed Amazonas, Av Gen Rodrigo Octavio Jordao Ramos 3000, BR-69077000 Manaus, AM, BrazilIIAP, Vv Jose Quinones Km 2-5,Apartado Postal 784, Iquitos, PeruIRD, UMR BOREA, MNHN, CNRS 7208,SU,UCN,UA,IRD 207, Ave Agropolis 911, F-34394 Montpellier, FranceUMSS, ULRA, FAUNAGUA, ECOSINTEGRALES SRL, Ave Max Fernandez Final S-N, Cochabamba, BoliviaECOSINTEGRALES SRL, Res Act, Carlos Muller St 211, Cochabamba, Cercado, BoliviaInst Amazon Invest Cient SINCHI, Ave Vasquez Cobo Entre Calles 15 & 16, Bogota, ColombiaUniv Fed Sao Paulo, Rua Doutor Carvalho Mendonca 144, BR-11070100 Santos, SP, BrazilCAPES [1402376, 047/2012, 6632/14-9]CNPq [204344/2015-8][PAREV/FAPEAM 019/2010]FAPESP [2016/07910-0]Web of Scienc

Review of river fisheries valuation in Central and South America

Unlike Africa and Asia, where a large part of the population are heavily dependent upon fishing for their livelihoods, fishing for a living in the interior of Central and South America (CSA) remains a marginal occupation for all but the most isolated of families. As such, the economics and management of fisheries on the continent have received little attention from within the continent and the rest of the world. This study shows that while a number of studies have been carried out on fishing in the region, they tend to be limited in their geographical focus and time scale. Although fishing of freshwater species may appear to be comparatively insignificant in the region, the rivers of CSA are very important. This report attempts to analyze the literature available on CSA river fisheries and attempts to draw out an economic value of these fisheries. It is divided into a number of sections. First, the authors describe the major river basins on the continent, characterize their fisheries, and place freshwater fisheries in CSA into a global context. Second, the authors provide a review of valuation techniques for fisheries and use this analytical framework to review the principal literature on freshwater fisheries in the region. Then they turn their attention to the economic impact of dams and water abstraction schemes, reviewing the available literature to ascertain how/if economic values are computed for the impact on fisheries. Finally, they offer some conclusions and recommendations on the direction for future studies of freshwater fisheries in CSA

Analysis of a multispecies fishery : the commercial fishery fleet of Iquitos, Amazon Basin, Peru

In this study an analysis of the commercial fishery of the Loreto Region, with emphasis on the fishery fleet of Iquitos, Amazon Basin, Peru, is presented. There is evidence of a progressive replacement of large species by smaller, more productive and lower value species in the landing of the commercial fishery in the Loreto region. Strong fishing pressure has produced a decrease of large valuable species such as Brachyplaiystoma flavicans in the commercial landings of the last ten years. No studies have evaluated the association between catch of the fishery fleet and amplitude and duration of the flooding and fishing effort in the Ucayali and Amazon rivers. Hydrological indices were based on the Amazon water stage taken at Iquitos gauge station in the last ten years. Hydrological indices and fishing effort were used as explanatory variables in a multiple linear regression to answer the question whether the factor responsible for the fluctuation in catch per guilds was the intensity of flooding or the severity of the draw-down period while accounting for fishing effort. This analysis was performed with index of the same year and index of the preceding year. The most significant variables were flood index of the same year and number of fishermen-trips. A positive influence of flooding on the omnivore group was evident in the Ucayali (p-value = 0.03) and Amazon (p-value = 0.001) rivers. However, this influence was negative (p-value = 0.03) on the detritivore group in the Ucayali River at high water which is interpreted as being due to reduced feeding places and stranding process. Number of fishermen-trips explains 90% and 96% of the variance of annual catches in the Ucayali and Amazon rivers, respectively. Additionally, six catch prediction models are presented

Spatial and temporal length distribution of Zungaro zungaro caught in the Orinoco River Basin of Colombia

Objective. To determine the effect of fishing on capture size of both male and female Zungaro zungaro catfish, historical records of size and spatial distribution of the species were analyzed from the Orinoco Basin in Colombian. Materials and methods. Information was collected by sampling fishing port landings in the region between 1979 and 2011. Each specimen was measured, weighed and sexed. With 5411 records, the average size at capture were compared in time and among the different ports. Size at 50% maturity was estimated by quinquennium. Results. The average commercial capture sizes of Z. zungaro ranged from 35 to 161 cm standard length, with differences between males and females. From 1979 to 2011, in Puerto Lopez, the size at sexual maturity decreased from 123.8 to 83.4 cm in females and from 93.3 to 61 in males. In the annual cycle the greater average capture size in females was from April to July and for males from May to June. Average annual length is higher in the higher parts of the Meta and Guaviare river drainages. In the last quinquennium the size at 50% maturity had fallen 10 cm in females and 5 cm in males and it is higher than the average capture size. Conclusions. Populations of Z. zungaro in the Colombian Orinoco River Basin have been affected by overfishing and selective fishing of females.Objetivo. Determinar el grado de afección en la población de Zungaro zungaro a partir del análisis del comportamiento histórico y espacial de las tallas de captura de hembras y machos de la especie en la Orinoquia colombiana. Materiales y métodos. La información fue colectada mediante muestreos a los desembarcos en puertos pesqueros de la región entre 1979 y 2011. Cada ejemplar fue medido, pesado y sexado. Con 5411 registros, se estableció la distribución de las tallas medias de captura, que se compararon en el tiempo y entre los diferentes puertos. Se estimó la talla de madurez gonadal (TMG) por quinquenios. Resultados. El rango de las tallas de captura comercial Z. zungaro fue de 35 a 161 cm longitud estándar (LS), con diferencia entre machos y hembras. Entre los años 1979 a 2011, en Puerto López, la talla promedio de captura anual (LS) disminuyó de 123.8 a 83.4 cm en hembras y de 93.3 a 61 cm en machos. En el ciclo anual la mayor talla promedio de captura de hembras se presenta en abril a julio y de machos en mayo y junio. La talla promedio de captura anual (TPCA) es superior en las partes altas de los ríos Meta y Guaviare. En el último quinquenio la TMG ha disminuido 10 cm en las hembras y cinco cm en los machos y es superior a la TPCA. Conclusiones. Hay afectación sobre la población explotada de Z. zungaro por sobrepesca por crecimiento y pesca selectiva de hembras en la Orinoquia colombiana

Aguas del Iténez o Guaporé

Bolivia y Brasil comparten una de las cuencas más atractivas y preservadas de la te-giuri amazônica: la cuenca del rio llénez o Guaporé, que escurre tanto sobre el lecho rocoso del Escudo Precámbrico Brasilefto como sobre las Hanuras del Beni. Estas influencias hacen que la cuenca del iténez tenga una elevada heterogeneidad de habitats, una fauna acuálica peculiar y un alto valor de conservation. Este patrimo­nio binacional posée un potencial importante para la conservación de la diversidad regional y cl dcsar rollo sostcniblc participativo de las comunidades locales. El libro contiene un resumen del conotimìento de la cuenca y sus recursos, generado en los últimos 10 anos por un equipo de investigadores bolivianos, brasilefios y de otras nacionalidades. Se presenta una descripeión del medio fisico, así como resultados relevantes sobre la biodiversidad acuática, con énfasis en algas, peces, reptiles y mamíferos. El aporte más notable del libro, adernas de la descripeión ecológica del ecosistema, son las lecciones aprendidas que surgieron de experiências locales sobre la élaboration participativa de herramientas para la gestion de los recursos hidrobiológicos.A Bolívia e o Brasil compartilham uma das bacias hidrográficas mais atrativas e preservadas da região amazônica: a bacia do Rio Iténez ou Guaporé. A combinação das influências do escudo pré-cambriano brasileiro e da planícies do Beni é uma das razões pela qual existem na região elevada heterogeneidade de habitats, fauna aquática peculiar e alto grau valor dc conservação. Eslc patrimônio binacional possui potencial significativo para a conservação da diversidade regional e desenvolvimento sustentável participativo das comunidades locais. O livro contém um resumo do conhecimento da bacia e seus recursos, gerado nos últimos dez anos por uma equipe de pesquisadores bolivianos, brasileiros e de outras nacionalidades. Apresentamos uma descrição do meio físico, bem como resultados relevantes da biodiversidade aquática, com ênfase em algas, peixes, répteis e mamíferos. A contribuição mais notável do livro, além da descrição ecológica do ecossistema, é a descrição das lições aprendidas que surgiram a partir de experiências locais sobre elaboração participativa de ferramentas para a gestão dos recursos aquáticos presentes nesta bacia

Tropical river fisheries valuation: background papers to a global synthesis

This report is a compilation of five regional reviews that document the global status of tropical rivers and inland fisheries in three continents: Latin America, Africa and Asia. It explores the role of ‘valuation’ methods and their contribution to policy-making and river fishery management. From the compilation, the best estimate of the global value of inland fisheries for those three continents is US$5.58 billion (gross market value), which is equivalent to 19 percent of the current value of annual fish exports from developing countries (US$ 29 billion) for 2004. The compilation shows that there is a general shortage of information on inland fisheries, especially derived from conventional economic valuation methods, though information from economic impact assessment methods and socio-economic and livelihood analysis methods is more widely available. The status of knowledge about the impact of changes in river management on the value of tropical river fisheries is weak and patchy. Although the impacts of large dams on the hydrology, ecology and livelihood support attributes of tropical rivers are well-recognized, there have been only few valuation studies of these issues. The document highlights the need for further valuation studies of tropical river and inland fisheries in developing countries. It underlines how vital it is for policy-makers and other stakeholders to understand the importance of these natural resources in order to make appropriate decisions concerning their role in development policy and illustrates why capacity building in valuation should become a major priority for agencies concerned with fisheries management and policy-making

The implications of manioc cultivation in the culture and mythology of the Machiguenga of South Eastern Peru

The aim of this thesis to effect an introduction to the place of manioc (Manihot esculenta Crantz) in the culture of the Machiguenga Indians of the Peruvian rain forest. The main substance of my work finds its focus in a myth, the narrative of which was recorded during fieldwork on location in the Urubamba region of south east Peru. My thesis will attempt to examine the role of manioc and the justification of its description as a 'sacred plant' the Machiguenga. The evidence I put forward to demonstrate the significance of manioc comes under the following headings: a) manioc cultivation and dietary uses b) manioc plant taxonomy c) the manioc myth itself, which I have transcribed and translated from my recordings. Whilst the anthropological structures of the myth are examined, no attempt will be made to deal in detail with the vocabulary and morphology of the Machiguenga language. While conceding that it is vital to show the connection between the material use of manioc and the belief structure surrounding it, material already collected would suggest a more ambitious piece of work than a Master of Philosophy degree would allow, and I hope in the future to undertake full-scale investigation into this largely untouched aspect of Machiguenga social and religious organization. The present work aims only at an introduction to the people and their use of manioc, and the presentation of the manioc myth

Tropical river fisheries valuation: background papers to a global synthesis

This report is a compilation of five regional reviews that document the global status of tropical rivers and inland fisheries in three continents: Latin America, Africa and Asia. It explores the role of valuation methods and their contribution to policy making and river fishery management.Inland fisheries, River basin management, River fisheries, Fresh water, Central America, South America, West Africa, Central Africa, South Africa, Asia, Southeast Asia, Mekong R.,