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Market price trends of Latin American and Caribbean sea cucumbers inform fisheries management
Abstract
Market price trends of seafood can inform fishery management measures and strengthen the bargaining power of fishers. The four-sided sea cucumber Isostichopus badionotus and donkey dung sea cucumber Holothuria mexicana are heavily exploited in small-scale fisheries in the Gulf of Mexico and Caribbean for export to China. We recorded prices and sizes of the dried sea cucumbers from 41 lots in 28 shops in Hong Kong and Guangzhou, China. Market value ranged 132–358 US$ kg⁻¹ for I. badionotus, and 16–209 US$ kg⁻¹ for H. mexicana. The relationship between product length and price per kg was weak for both species, revealing large variability in the marketplace. Price per individual increased linearly with product length for H. mexicana, and increased nonlinearly for I. badionotus indicating that large specimens were disproportionately more valuable than small ones. Thus, the economic performance of fisheries, especially those for I. badionotus, could be optimised by strictly enforcing large minimum size limits. High market value identifies I. badionotus as a species of conservation concern. A large difference between reported prices received by fishers and market retail prices suggests substantial scope for upgrading value chains of small-scale export fisheries.
... The high demand of the Asian market for the traditional, medicinal, and luxury consumption of some species of sea cucumber has led to the rapid opening of its fisheries around the world (Purcell et al. 2018). This, in turn, has resulted in the overexploitation and decay of populations of many species of sea cucumber in several countries (López-Rocha and Velázquez-Abunader 2019; Sánchez-Tapia et al. 2019; Communicated by Erko Stackebrandt. ...
... In Mexico, specifically on the Yucatan Peninsula, five species of sea cucumber are considered of commercial importance (Astichopus multifidus, Holothuria floridana, H. mexicana, H. grisea, and Isostichopus badionotus), with I. badionotus being the most commercially relevant. This species is sold in the Asian market between 132 and 402 USD per kg of dry product (INAPESCA 2015;Purcell et al. 2018;Sánchez-Tapia et al. 2019;Gamboa-Álvarez et al. 2020). ...
... Isostichopus badionotus is an epibenthic deposit feeder widely distributed on shallow muddy, sandy, and seagrass beds from North Carolina to Brazil, the Great Caribbean, and across the Atlantic Ocean to West Africa (Miller and Pawson 1984;Purcell et al. 2012). Unfortunately, in less than 15 years, the natural populations of this species have been substantially reduced (between 70 and 90%) from Mexico to South America by overfishing (Purcell et al. 2013(Purcell et al. , 2018. ...
For the first time, this study analyses the composition and diversity of the gut microbiota of Isostichopus badionotus in captivity, using high-throughput 16S rRNA sequencing, and predicts the metagenomic functions of the microbiota. The results revealed a different composition of the gut microbiota for the foregut (FG) and midgut (MG) compared to the hindgut (HG), with a predominance of Proteobacteria, followed by Actinobacteria, Bacteroidetes, and Firmicutes. The FG and MG demonstrated a greater bacterial diversity compared to the HG. In addition, a complex network of interactions was observed at the genus level and identified some strains with probiotic and bioremediation potentials, such as Acinetobacter, Rue-geria, Streptococcus, Lactobacillus, Pseudomonas, Enterobacter, Aeromonas, Rhodopseudomonas, Agarivorans, Bacillus, Enterococcus, Micrococcus, Bifidobacterium, and Shewanella. Predicting metabolic pathways revealed that the bacterial composition in each section of the intestine participates in different physiological processes such as metabolism, genetic and environmental information processing, organismal systems, and cellular processes. Understanding and manipulating microbe-host-environment interactions and their associated functional capacity could substantially contribute to achieving more sustainable aquaculture systems for I. badionotus.
... Most products of H. scabra are exported to China or to countries where the Chinese community is important. Purcell et al. (2018c) examined recent changes in retail prices of bechede-mer in both Hong Kong and mainland China markets and assessed the relationships between product size and price across multiple species (including H. scabra) harvested and exported from the tropical Indo-Pacific region. In 2016, average retail prices of beche-de-mer were 1.3-3.8-fold ...
... In 2016, average retail prices of beche-de-mer were 1.3-3.8-fold higher in Hong Kong stores than in Guangzhou stores (Purcell et al., 2018c). The tropical species with the highest maximum recorded price was H. scabra, for which extra-large, premium quality products were retailing at over 1800 USD per kg at one Hong Kong store (Purcell et al., 2018c). ...
... higher in Hong Kong stores than in Guangzhou stores (Purcell et al., 2018c). The tropical species with the highest maximum recorded price was H. scabra, for which extra-large, premium quality products were retailing at over 1800 USD per kg at one Hong Kong store (Purcell et al., 2018c). These more expensive products were exceptionally large specimens that would probably have weighed 1.5-2 kg live. ...
Holothuria scabra is one of the most intensively studied holothuroids, or sea cucumbers (Echinodermata: Holothuroidea), having been discussed in the literature since the early 19th century. The species is important for several reasons: (1) it is widely distributed and historically abundant in several shallow soft-bottom habitats throughout the Indo-Pacific, (2) it has a high commercial value on the Asian markets, where it is mainly sold as a dried product (beche-de-mer) and (3) it is the only tropical holothuroid species that can currently be mass-produced in hatcheries. Over 20 years have elapsed since the last comprehensive review on H. scabra published in 2001. Research on H. scabra has continued to accumulate, fuelled by intense commercial exploitation, and further declines in wild stocks over the entire distribution range. This review compiles data from over 950 publications pertaining to the biology, ecology, physiology, biochemical composition, aquaculture, fishery, processing and trade of H. scabra, presenting the most complete synthesis to date, including scientific papers and material published by local institutions and/or in foreign languages. The main goal of this project was to summarize and critically discuss the abundant literature on this species, making it more readily accessible to all stakeholders aiming to conduct fundamental and applied research on H. scabra, or wishing to develop aquaculture, stock enhancement and management programs across its geographic range.
... La CV de pulpo muestra un patrón similar al de "reloj de arena", caracterizado por una base conformada por un gran número de extractores e intermediarios, en el medio pocos actores con influencia en toda la producción y vinculados principalmente al proceso de exportación y en la base opuesta un gran número de distribuidores y consumidores (Purcell et al., 2017). Este patrón también ha sido reportado en diferentes pesquerías y agro-negocios enfocados a alimentos de alto valor (Gereffi & Lee, 2012;Wamukota et al., 2014;Drury O'Neill et al., 2018;Purcell et al., 2018). ...
... Varios autores Purcell et al., 2018;Silva et al., 2019) han referido a el papel que juegan los consumidores dentro de la cadena y la importancia en transferir información a este sector para reducir la presión sobre los recursos. Los turistas y los consumidores nacionales son menos estrictos con respecto a la calidad de los productos demandados (en comparación con los mercados internacionales) y parecen menos conscientes de la importancia de controlar el consumo de pulpo durante la temporada de veda; por lo que campañas de información a este sector resulta prioritario. ...
... (Kaplinsky & Morris, 2001; M4P, 2008, p. 4;FAO, 2014). La CV también identifica el valor del producto a lo largo del flujo de la producción, desde la extracción, las fases intermedias de la producción incluyendo los actores involucrados, hasta el consumidor final(Porter, 1985;Kaplinsky & Morris, 2001;FAO, 2014).Los análisis de CV en pesquerías en general se han desarrollado desde una perspectiva económica para conocer el valor de los recursos y los desbalances de beneficios entre actores (M4P, 2008;Butler et al., 2013;Bjørndal, 2014Bjørndal, , 2014Wamukota et al., 2014;Crona et al., 2016;Hamilton-Hart & Stringer, 2016;Purcell et al., 2017Purcell et al., , 2018Drury O'Neill et al., 2018;Nasr-Allah et al., 2019). Recientemente se ha comenzado a desarrollar mapeos de la estructura de la producción y evaluar las relaciones entre actores, para buscar estrategias colectivas de mejora, que van más allá del aspecto comercial y que pretende alcanzar resultados integrales entre aspectos sociales, ambientales y de ...
Las pesquerías de pequeña escala (PPE) integran sistemas naturales y socio-económicos altamente complejos, diversos y dinámicos; estas características han dificultado históricamente la evaluación y gestión de este sector. Aunque las PPE han recibido mayor atención en años recientes a través de iniciativas internacionales que promueven evaluaciones y manejo integral, estas prácticas aun no son comunes globalmente, especialmente en países en vías de desarrollo.
En un intento por abordar dicha complejidad, esta tesis tiene como objetivo analizar las PPE de la Península de Yucatán (PY), México, bajo un enfoque transdisciplinario en el contexto de actividades de pre-captura, captura y pos-captura teniendo como objetivos: a) identificar la complejidad de las PPE y contrastar a través de una tipología diferencias entre comunidades, b) identificar actores y sus interacciones dentro de la cadena de valor (CV) de la pesquería de pulpo y c) identificar las características que influencian la gobernabilidad del sistema pesquero. La estrategia de investigación usada en esta tesis fue dividir el estudio en tres secciones abordando las siguientes preguntas: i) ¿Existen atributos heterogéneos de las PPE en las comunidades pesqueras que comparten recursos y formas de manejo semejantes?; ii) ¿cómo se estructura la CV de la pesquería de pulpo de la YP y qué tipo de arreglos sociales y de mercado existen? y iii) ¿qué factores definen la gobernabilidad de las PPE en la PY? Las preguntas se atendieron usando tres marcos analíticos: análisis tipológico de las pesquerías en 22 comunidades pesqueras, análisis de cadena de valor de la pesquería del pulpo y evaluación de gobernabilidad de las PPE de la PY.
Los resultados se reportan en capítulos auto contenidos. Las fuentes de información usados en esta investigación provienen de datos oficiales de dependencias locales, nacionales e internacionales, entrevistas con actores del sector pesquero y observación participativa no intrusiva en 7 comunidades pesqueras. La información contiene datos de 2006-2017.
Los resultados muestran que las PPE reportan 142 especies, que contribuyen con el 70% del volumen de la producción total en la región. Estas especies se integran en nueve pesquerías, donde operan el 85% de pescadores y embarcaciones de la PY. La tipología clasificó tres “tipos” de PPE diferenciados por su producción pesquera, las especies desembarcadas (destacando el pulpo), el esfuerzo de pesca y los ingresos económicos de los pescadores, mostrando la heterogeneidad y complejidad del sistema de PPE en la PY. Este análisis permitió analizar el sistema pesquero en grupos de comunidades diferenciados por perfiles, los contrastes observados entre los grupos demandan atención adecuada a sus características en cuanto a implementación de estrategias de manejo en estas pesquerías.
La estructura de la cadena de valor de la pesquería de pulpo mostró alta complejidad con diversidad de actores desde el ámbito comunitario hasta la exportación. Se identificaron diversos actores, formales e informarles, interconectados a través de complejos acuerdos económicos y sociales. Se destaca el poder económico y de comercialización de las empresas exportadoras a lo largo de toda la cadena y la participación de actores no reconocidos oficialmente, principalmente mujeres y niños. Dada la alta demanda internacional de pulpo y su relevancia pesquera a nivel regional, es fundamental comprender la estructura y dinámica de su cadena de valor para promover prácticas de mercado sostenibles.
La complejidad reflejada en los recursos, las operaciones de pesca y los mercados, es manifiesta en el sistema de PPE. A esto se agrega una complejidad biogeográfica que cambia entre estados a lo largo de la región. Esta alta diversidad de especies, usuarios, distribuidores y comercializadores, y una limitada interacción entre usuarios e instituciones parece limitar la gobernabilidad de las PPE. El esquema de gestión actual opera bajo un enfoque de arriba hacia abajo (control gubernamental), prestando poca atención al componente socio-económico, cultural y de género de los sistemas pesqueros, limitando por tanto la participación de los usuarios en procesos de decisiones y la definición de políticas pesqueras. Este contexto demanda un involucramiento de los usuarios dentro de procesos adaptativos de gestión acordes a la complejidad que se enfrenta.
La presente tesis ofrece un marco analítico para comprender la complejidad, diversidad y heterogeneidad de un sistema de PPE. Además, contribuye con un cambio de visión de los paradigmas de investigación tradicionales, ofreciendo propuestas metodológicas replicables en otros sistemas que integren PPE. Se espera que el conocimiento generando facilite procedimientos de monitoreo, promueva la interacción entre instituciones y usuarios y un cambio de perspectivas dirigidas a enfoques transdisciplinarios que integren conocimiento técnico y local para abordar las complejidades de las PPE. Se espera que esto ayude en la búsqueda de mejores prácticas de pesca, mercados y finalmente en el manejo sostenible de las PPE.
... Tracking the octopus production flow from the landings in the communities to the international markets, as depicted in Fig. 3, reveals complex and multifaceted interactions among a diversity of actors and companies in an intricate socio-economic setting. The octopus value chain in the YP shows a "sand clock" pattern similar to the one reported in the case of the sea cucumber fishery in Fiji [10] and also to many other cases linked to agro-food targeting resources of high value [17,22,48]. This pattern is characterized by many producers, an unknown number of middlemen, a few key/leading actors who operate across the chain, and a diversity of consumers. ...
... Fishers and collectors have limited power for bargaining prices because they are highly dependent on wholesalers. This limited capacity for price negotiation by fishers has been reported in different fisheries globally [7,9,22,48]. ...
... The increasing demand for seafood products from domestic to international markets in the short and long term can have double effects on the resources and the fishing communities. As stated by several authors [10,55], on the one hand, the seafood trade can be a source of income for developing countries and improve the wealth of coastal communities; on the other hand, it can also be an incentive for resource overexploitation, especially when it comes to high-value species that are exported overseas [2,10,48], as in the case of the Mexican octopus. Mapping the seafood value chains is fundamental to improving the knowledge about actors' roles and the strengths and constraints of the chain so that new policy perspectives can be elucidated from this learning process. ...
The growing trend on seafood trade from domestic to international markets calls for an understanding of the socioeconomic structure operating in fisheries value chains. In this paper, a structural mapping approach was used to identify catch trends, prevalent forms of coordination among actors, and the key players involved in the octopus production chain in Mexico. The analysis also allowed to track products along the stream, and assess how octopus prices change through the chain. Data came from governmental agencies and in-depth interviews with key actors. The study highlights multiple linkages among a diversity of actors within the chain, which is shaped by the leading firms that control the exportation. The fishers comprise the largest group in the production chain, but they are nevertheless the least empowered among the traders. Formal and informal arrangements among actors create dependence of fishers on middlemen and wholesalers. The study also reveals concern about informal harvest and trade, which could place the octopus stock and its trade at risk. The paper concludes with remarks about the role that the expansion of trade can have in shaping the way fisheries operate, and the need for institutional arrangements that lead to sustainable fisheries and fair trade.
... This has been the main reason why sea cucumber catches have typically followed a boom and bust trajectory, characterized by rapid development and predictable collapse after a few years [27]. Some of the causes of this phenomena have been widely reported as illegal fishing and overexploitation of sea cucumber, and in many cases this has ended in the closure of the fishery [7,23,25,26,[28][29][30][31][32]. ...
... Therefore, the most important factor that has shaped the institutional structure in the sea cucumber are the high market prices. It has been documented that high market prices strongly affect sea food exploitation rates and the risk of overfishing [32]. The increasing demand and high prices facilitated the appearance of multiple groups of actors making compliance and enforcement more difficult because the rule making from the State was slow and weak to be enforced. ...
Formal and informal institutions govern fisheries around the world. Yucatan’s sea cucumber fishery is not an exemption, the sudden and fast development of the fishery in 2010 has motivated the creation of informal and illegal forms of organization. The prices, buyers’ interest and the fishing effort substantially increased, being followed by illegal fishing-fishers and traders, creating informal fishing-trade channels and severe social and biological concerns. This article aims to give account of the emergence and dynamics of the informal institutions which currently dominate this fishery. It was sought to identify the extent to which rules and regulations are not being respected and how they are affecting fish resources and coastal communities. We considered the case of the port of Sisal, Yucatan, Mexico to illustrate our argument and here we applied a mixture of qualitative and quantitative methodologies including informal and in-depth interviews applied to 17 key informants, a questionnaire applied to 47 fishers and an estimation of the degree of compliance from three of the main management measures. Socio-biological negative impacts were identified in Yucatan’s coastal communities and its fisheries. Foreign buyers and local middlemen exert high pressure on fishers to exceed the quota and catch the highest possible volumes facilitating the fisheries decline. This and the growing economic interest motivated the development of strong informal institutions supporting illegal fishing and informal trade. Social problems emerged and women were particularly affected. The economic power of the fishery is likely to overcome any type of governance structure. The enforcement of entry rules was not effective, so the governance base was around informality and illegal actions. Local and foreign buyers are exerting pressure to increase the catch volume thus it is recommended that rules and regulations be directed at buyers and exporting companies rather than at fishers.
... Sea cucumbers (Holothuroidea) are invertebrates that move slowly and live in contact or buried in the sediment; they have an essential role in the marine ecosystem by recycling nutrients, and therefore, they can directly accumulate metals from the sediment because it is their food source [5,6]. Consequently, a scientific interest focused on the use and conservation of sea cucumber has increased in the recent years [7][8][9]. These organisms have been considered appropriate to be used as biomonitors because they have certain characteristics such as type of feeding, easy identification, low mobility, and small size, although with enough tissue to perform analysis of contaminants [10,11]. ...
... Sea cucumbers are classified commercially important according to the different types of species, organoleptic characteristics (color, appearance, smell, body thickness), abundance, and demand in the global market [15]. Although sea cucumbers are consumed as part of the Asian tradition, for their medicinal benefits and as part of culinary delicacy [6,9], the H. floridana species still does not have great value as food, although the constant pressure and overexploitation of other sea cucumbers could increase their future demand. ...
Sea cucumbers are fished worldwide for export to Asia, but few studies have evaluated metal pollution and risk assessment. This study assessed concentration of trace metals and the potential ecological risk in sea cucumber (Holothuria floridana) and sediments at the Cispatá Bay, in the Caribbean Coast of Colombia. The trace metal concentrations in biota and sediments showed a similar decreasing trend as follows: Cu > Zn > Hg > Pb > Cd. The highest bioconcentration factor was found for Hg, and according to the sediment quality guidelines, Cu levels indicate adverse biological effects in the ecosystem. In this regard, Cu levels were higher than effects range low and the threshold effect levels (TEL) and lowest effect level in all the stations, whereas Hg levels were higher than TEL in most of them. Results for health risk assessment based on the maximum allowable daily consumption rate (CRlim) suggest that there is no risk to adults; however, children should limit or avoid its consumption. Results from multivariate statistical analysis suggest that agricultural activities (i.e., application of fertilizers and agrochemicals) were identified as the main anthropogenic sources of metal pollution. This research suggest that sea cucumber could be used as a bioindicator species in studies of monitoring metal contamination, with special attention to the highly significant correlation between Zn in tissue and sediments. This study also reveals that anthropic activities may have negative effects in the quality of the sediments of the bay and contributing to the knowledge of metal accumulation in sea cucumber.
Graphical abstract
... It is evident that the current conformation of the network benefits very few traders and will not allow the empowerment of the rest (fishermen associated in cooperatives or employees of permit holders) of the network to improve the benefits generated by the sea cucumber market. This fact coincides with what was noted by Purcell et al. (2018) for other sea cucumber fisheries in the Caribbean and in Latin America where there is a disproportion between the wealth generated between fishermen and exporters. However, according to Casillas et al. (2006), this conformation is common in a socio-economic system that shows an unequal distribution of resources since a small percentage of actors monopolize a large percentage of the system's resources following the Pareto Law. ...
... This study is limited to incorporated fluxes throughout the network. Purcell et al. (2018) emphasizes that two variables (i.e., price and size) and the relationship between them is important to assess fair trade, conservation and fisheries management strategies. This information could allow for the identification of requirements for upgrading value chains of small-scale fishers, as indicated by Brown et al. (2010) and Mangubhai et al. (2017). ...
Understanding fishery market systems is vital to promoting the efficient development of small-scale fisheries. It can assist in the refocusing of public policy on goals beyond merely maintaining production, which promotes the construction of social capital that favors governance in environmental and/or economic crises. This study is an analysis of the Yucatan (Mexico) sea cucumber (Isostichopus badionotus) trade network examining seven ports; it analyses the social network to describe its structure, the communities within it, the actors and their roles (cooperative fishers, permit holders and traders), and its robustness. The analyzed network is a scale-free type in which 80% of sea cucumber trade actors are related to one of them and control 66% of the entire network transactions. It is a robust network that is resistant to random attacks but is clearly vulnerable to focused attacks. Descriptions are provided of the characteristics of its communities and of its subnetworks in the most important ports. The most relevant actors in system connectivity were identified, and the structural properties of the network were calculated. The results are presented comparatively between the original system and a simulated scenario where the most connected actor is eliminated. This study is an important baseline for later analyses of how the local sea cucumber trade network may respond to internal and external stressors.
... In the Colombian Caribbean, where there is illegal, unquantified and unregulated fishing of several species of sea cucumbers (Ortega-Lara et al., 2015;Puentes et al., 2014;Reyes-Sánchez et al., 2011;Rodríguez et al., 2013), one of the species that arouses greater interest for its conservation and culture is Isostichopus badionotus, not only because it is one of the most intensely fished due to its high economic value Puentes et al., 2014;Purcell et al., 2018;Rodríguez et al., 2013), but also for its potential for aquaculture (Purcell et al., 2012;Sánchez, 2012;Rodríguez-Serna et al., 2012;Zacarías-Soto et al., 2013;Zacarías-Soto & Olvera-Novoa, 2015). ...
Isostichopus sp. is a variety of Isostichopus badionotus, proposed as a new species, which has been intensely fished in the Colombian Caribbean, arousing interest for its aquaculture. This study evaluated the effect of two culture densities (1–3 larvae ml−1), two temperatures (23°C and 26°C) and two microalgae diets (Isochrysis galbana, Chaetoceros calcitrans, Nannochloropsis oculata 1:1:1 and I. galbana, C. calcitrans 1:1) on the survival, development and growth of its larvae. Larval culture lasted 22 days until metamorphosis to doliolaria larvae, and 7 days later, the first juveniles were observed with a size of 621.8 ± 12.7 μm (±SE). The highest growth rates, survival and percentage of doliolaria larvae were obtained with 1 larva ml−1 (29.2 μm/day and 31.5% doliolaria larvae) and 26°C (28.4 μm/day and 10% doliolaria larvae). However, in the two diets examined, the larvae showed low growth rates (between 1.3 and 8.5 μm/day), stagnation in development and high mortality. Our results indicate that it is feasible to culture larvae from Isostichopus sp. to juveniles, recommending the use of 1 larva ml−1 and 26°C. However, to meet the nutritional needs of the larvae the inclusion of microalgae Pavlova sp. and Tetraselmis chuii in the diet is recommended. This paper reports for the first time the successful production of sea cucumber juveniles of this species in Colombia.
... In the Colombian Caribbean, where there is illegal, unquantified and unregulated fishing of several species of sea cucumbers (Ortega-Lara et al., 2015;Puentes et al., 2014;Reyes-Sánchez et al., 2011;Rodríguez et al., 2013), one of the species that arouses greater interest for its conservation and culture is Isostichopus badionotus, not only because it is one of the most intensely fished due to its high economic value Puentes et al., 2014;Purcell et al., 2018;Rodríguez et al., 2013), but also for its potential for aquaculture (Purcell et al., 2012;Sánchez, 2012;Rodríguez-Serna et al., 2012;Zacarías-Soto et al., 2013;Zacarías-Soto & Olvera-Novoa, 2015). ...
Isostichopus sp. is a variety of Isostichopus badionotus, proposed as a new species, which has been intensely fished in the Colombian Caribbean, arousing interest for its aquaculture. This study evaluated the effect of two culture densities (1–3 larvae ml−1), two temperatures (23°C and 26°C) and two microalgae diets (Isochrysis galbana, Chaetoceros calcitrans, Nannochloropsis oculata 1:1:1 and I. galbana, C. calcitrans 1:1) on the survival, development and growth of its larvae. Larval culture lasted 22 days until metamorphosis to doliolaria larvae, and 7 days later, the first juveniles were
observed with a size of 621.8 ± 12.7 µm (±SE). The highest growth rates, survival and percentage of doliolaria larvae were obtained with 1 larva ml−1 (29.2 µm/day and 31.5% doliolaria larvae) and 26°C (28.4 µm/day and 10% doliolaria larvae). However, in the two diets examined, the larvae showed low growth rates (between 1.3 and
8.5 µm/day), stagnation in development and high mortality. Our results indicate that it is feasible to culture larvae from Isostichopus sp. to juveniles, recommending the use of 1 larva ml−1 and 26°C. However, to meet the nutritional needs of the larvae the inclusion of microalgae Pavlova sp. and Tetraselmis chuii in the diet is recommended. This paper reports for the first time the successful production of sea cucumber juve-niles of this species in Colombia.
... Indeed the huge quotas granted in 2008 (2,110,240 pieces to 10 permit holders) may be responsible of the drastic decline of the population which forced severe reductions in quotas as well as the number of permit holders thereafter. Moreover, Purcell et al. (2018) pointed out that because most sea cucumber species are long-lived and with low productivity as is the case for I. fuscus, removing a very small fraction (2-4%) may deplete breeding stocks. Uthicke et al. (2004) documented that annual catches < 5% of virgin biomass depleted populations of Holothuria nobilis in the Great Barrier and suggested an extremely cautious approach in the management of beche-de-mer fisheries. ...
There is an increasing demand for fisheries resources worldwide. For example, the Asian markets have traditionally consumed sea cucumber as a delicacy and their buoyant economies have promoted demand for it in recent years. The brown sea cucumber Isostichopus fuscus is the most valuable species from the Eastern Pacific and it has been almost depleted due to overfishing. In this work, we analyzed data of sea cucumber abundance collected monthly (October 2014–December 2016) along the west coast of the Gulf of California (29.95 oN – 28.05 oN) in 1,107 swath (25 × 2 m) quadrats performed at 118 sites with the goal of determining if current fishing quotas are sustainable. We applied a Bayesian hierarchical modelling approach with integrated nested Laplace approximation (INLA) to this data to account for spatial structure in the data when calculating densities. The observed density ranged from a minimum of 0 to a maximum of 0.58 ind/m2, with an average of 0.03 ind/m2 in suitable habitat, defined as the habitat less than 30 m deep and with hard substrate. There are large spatial variations in abundance, but the overall mean suitable habitat is 15.7% (min = 7.8%, max = 28.8%) of the total fishing area. Current quotas are usually higher than 5% of the lower bounds of population density estimates. We propose, among other management measures, that quotas should be granted taking into account the spatial structure of sea cucumber densities as well as the proportion of suitable area within each estate. Given the high levels of illegal fishing within the Gulf of California, it is imperative that quotas are based on the lower bounds of spatially explicit density estimates – along with increased surveillance and enforcement – if the long-term commercial sustainability of the fishery is to be maintained.
Holothuria scabra Jaeger 1833, known as sandfish visually, Its visible external body has a soft, flexible texture. Sandfish is included in the Echinodermata phylum and Holothuroidea class, which has an important ecological and economic role. This research proposes to decide the suitability site in an intermediate culture model of sea ranching harvest type based on ecological, socio-cultural and Karimunjawa National Park zoning plan. Data collected has done in March 2020, November 2020 and August 2021. The data analysed on the environmental suitability level was based on several essential criteria matrices used by ArcGIS 10.8.2. They were four classes performed (high suitable, suitable that is enough, suitable with conditionals, and not suitable) based on each variable and matrix classification from main factor (6 variables), supporting factor (5 variables), dan another factors (1 variable). The highest score was 35, and the lowest was 23 during the class interval value. The analysis showed that the aquatic environment that was High Suitable (S1) for sandfish life was Gede Lagoon. It has been determined to be highly suitable for developing sandfish cultivation. Furthermore, the Sea Ranching Harvesting Type development would recommend being carried out in waters that do not have limiting factors.
Introduction: Central America, a narrow strip of land dividing the Atlantic and Pacific oceans, has a high diversity of marine and terrestrial species. Echinoderms are one of the most diverse marine groups with 420 reported species. Objective: To summarize echinoderm research in Central America. Methods: We compiled the literature from SCOPUS, Web of Science, SciELO, Google Scholar, Biodiversity Heritage Library, the Internet Archive and the Smithsonian Library. Results: We found 324 publications dating from 1840 to 2020; the early studies had a strong taxonomic focus, but after the 1970s, ecology, evolution and reproduction gained prominence. Echinoidea is the most studied class (38% of publications) due to its use in evolutionary studies as well as the importance of the genus Diadema in reef ecology and dynamics. Conclusion: We recommend more research on fisheries management, conservation and environmental education; and greater integration of local and international research.
There is a demand for proper feed and feeding strategies in the growing sea cucumber aquaculture. The digestive system of holothurians seems to increase nutrient assimilation through the respiratory tree (RT), but digestive functioning in this organ has not been investigated. This study evaluated the enzymatic activity of the cytosolic leucine alanine peptidase (leu‐ala) and acid phosphatase, the membrane‐linked aminopeptidase‐N (APN), the bile salt‐activated lipase, laminarinase (LAM), and β‐glycosidase (BGL), in the RT and segments of the digestive tract (DT; foregut, midgut, and hindgut) of adult Isostichopus badionotus. All enzymes, except LAM and BGL, exhibited comparable activity levels in the RT and the DT segments, but APN and BGL activities were significantly higher in the whole DT compared with those in RT, with high activity of leu‐ala in both organs. These results indicate a relevant role of the RT as an accessory organ in sea cucumber digestive physiology. Consequently, I. badionotus seems to be able to digest feeds from the water column through the RT, maximizing the use of available nutrients by luminal, intracellular, and apical membrane‐linked digestive modes. These findings expand the knowledge of sea cucumber digestive mechanisms, with implications for developing feeding strategies for all life stages in aquaculture.
Introducción:
La acuicultura de equinodermos en América Latina es incipiente, pero representa una nueva frontera para la producción de alimentos marinos altamente nutritivos, con especies nativas de alto valor comercial que ofrecen un gran potencial en comparación con las debilitadas pesquerías bentónicas artesanales.
Metodología:
Se revisó la literatura sobre pepinos de mar, erizos de mar y estrellas de mar hasta el año 2020.
Resultados:
Para el 2020, había 17 especies nativas con importantes avances en reproducción, larvicultura, crecimiento, tratamiento e identificación de enfermedades y nutrición en México, Belice, Panamá, Colombia, Ecuador, Perú, Brasil, Chile y Argentina.
Conclusiones:
La acuicultura de equinodermos en América Latina está avanzando y se beneficiaría de los sistemas multitróficos para expandirse y diversificarse, reduciendo la presión sobre las pesquerías agotadas.
Isostichopus badionotus and Isostichopus sp. are two holothuroids exploited in the Caribbean region of Colombia. Until recently, they were considered a single species. During one year, 222 individuals of Isostichopus sp. and 114 of I . badionotus were collected in two bays of the Santa Marta region to study their reproductive biology and collect information on their size, weight and habitat. Both sea cucumber morphotypes showed an annual reproductive cycle, with a reproductive season from September to November, closely related to the increase in water temperature and rainfall. In both sea cucumbers the population structure exhibited a unimodal distribution composed of mature individuals and a sex ratio of 1:1. Isostichopus sp. had an average size and weight (193 ± 52 mm and 178 ± 69 g) and size and weight at first maturity (175 mm and 155 g) that was much lower than I . badionotus (respectively, 324 ± 70 mm and 628 ± 179 g; 220 mm and 348 g). While 98% of Isostichopus sp. individuals were collected in the upper 2.5 m, on rocky bottoms between cracks, 73% of I . badionotus individuals were found between 3 and 7.8 m depth, exposed on sandy bottoms. These differences imply that management measures (e.g. minimum catch size) should not be the same for both sea cucumbers morphotypes.
The illegal harvest of marine species within exclusive economic zones can have a strong impact on the function of local ecosystems and livelihoods of coastal communities. The complexity of these problems is often overlooked in the development of solutions, leading to ineffective and sometimes harmful social and environmental outcomes. One-dimensional, oversimplified perspectives can lead to conservation prescriptions that exacerbate social stressors. This is particularly critical in the case of international illegal trade of endangered, high-value species, which generate a value chain in which artisanal fishers are the first operational and often the weakest link of an intricate web. We examined 2 illegal fisheries, totoaba (Totoaba macdonaldi) and sea cucumber (Isostichopus badionotus and Holothuria floridana), in Mexico. Although these are 2 separate and independent fisheries, important ecological (resource condition, fishery impacts at the ecosystem level) and social (governance, markets) similarities improve understanding of their complexity. Our findings are relevant globally and show the need for interdisciplinary decision-making groups, community engagement, and the development of demand reduction measures.
Growing trade networks through globalization have expanded governance of local environments to encompass multiple scales. The governing role of market actors, such as traders and consumers in importing countries, has been recognized and embraced for sustainable seafood sourcing and trade. The perceptions that affect the conduct of these actors are a potential influence on governance of distal environments. In this paper we investigate the perceptions of sea cucumber traders in China. Sea cucumbers are an important global fishery commodity predominantly traded to China, the world's largest seafood market, and seven traded species are endangered globally. We examine what traders and consumers in China perceive as important issues in seafood markets, and where they perceive the responsibility for sustainable fisheries to lie, to interpret what scope there is for sustainability to become an important issue in China's seafood markets. We find that clusters of perceptions about cultural status, quality, health and food safety, and country of origin influence decisions that consumers make. These norms are rooted in sociocultural practice and drive current trade strategies. While traders do want to mitigate risks and secure supplies, food safety, product quality and country of origin are viewed as more important concerns than stock sustainability. Responsibility for sustainable fishing is perceived to be that of national governments in production countries. Trading practices and consumer perceptions together pose a serious challenge to sustainable seafood markets, further confounded by clandestine cross-border gray trade into China.
The large sea cucumber Holothuria sp. (type “pentard”) is exploited extensively throughout the western
Indian Ocean, yet little information exists on its market value at the distal end of the value chain. We collected
data on prices and sizes of this species from 15 lots in 14 shops in Hong Kong and Guangzhou. This
species was relatively common in the marketplace. Market values ranged from USD 44–273 kg-1 dried.
Weight-to-length ratios were lower for pentard than white teatfish (H. fuscogilva), but only marginally.
Prices per piece increased dramatically as a function of product length, but the relationship was weak for
price per kg. This market study verifies that pentard is highly valuable in Asian markets, and therefore is
likely to be at high risk of overexploitation. Our results show that fishery income from harvests of pentard
could be considerably higher in the long run by regulating catches to large-sized animals.
Tropical sea cucumber, called béche-de-mer (BDM) in its dried form, is a luxury seafood and health food, with its main market in southern China and smaller markets in Singapore, Malaysia and other countries.1 Regional markets for BDM have existed for centuries, and they have expanded greatly since the 1980s with growing incomes in China. Sea cucumbers are relatively easy to harvest and process, even in remote coastal and island locations in Papua New Guinea (PNG) (see Figure 1). Once dried, BDM is shelf stable and high value relative to its size and weight, so it is an ideal cash-earning commodity for communities where cashearning opportunities are extremely limited. Increasing prices and an influx of buyers entering the trade seeking BDM led to overfishing in PNG in the 2000s. In 2009 the government instituted a moratorium on the fishery, banning exports, and the PNG National Fisheries Authority (NFA) closed the fishery. Since then the NFA has revised the sea cucumber fishery Management Plan and conducted stock assessments in preparation for re-opening the fishery in 2017.
The objective of this study was to conduct a governance analysis that will assist the NFA and other stakeholders to grasp the factors influencing the effectiveness of the new Management Plan. We employed the ‘interactive governance’ approach, wherein ideas from governance studies have been developed for use in fisheries management (Kooiman et al. 2005; Jentoft and Chuenpagdee 2015). In this approach all of the factors affecting the governance of a fishery – human and non-human, government, civil society and market – are considered. Furthermore, these governance influences are considered at the various scales relevant to the fishery, from local to national and global. The research utilizes qualitative methods, with data collected from interviews with fishers and traders in PNG and China, BDM scientists and policy makers around the world, in addition to conducting an extensive literature review.
Sea cucumbers are exploited and traded in more than 70 countries worldwide. This book provides identification information on 58 species of sea cucumbers that are commonly exploited in artisanal and industrial fisheries around the world. Not all exploited species are included. It is intended for fishery managers, scientists, trade officers and industry workers. This book gives key information to enable species to be distinguished from each other, both in the live and processed (dried) forms. Where available for each species, the following information has been included: nomenclature together with FAO names and known common names used in different countries and regions; scientific illustrations of the body and ossicles; descriptions of ossicles present in different body parts; a colour photograph of live and dried specimens; basic information on size, habitat, biology, fisheries, human consumption, market value and trade; geographic distribution maps. The volume is fully indexed and contains an introduction, a glossary, and a dedicated bibliography.
The goal of Fair Trade certification is to contribute to sustainable development by offering trading con-ditions that are transparent and equitable. One important condition is improved market access andstrengthened producer organizations. In regions like Southeast Asia this goal can be hard to achievein value chains where local middlemen play a central role in not only trading fish, but also providing fish-ers with access to capital, infrastructure and essential services. Despite these contributions, Fair Tradeprinciples presume that middlemen adversely control market benefits that should accrue to primary pro-ducers. The social and economic contributions of middlemen, and the potentially dependent relationshipfishers have with them, is therefore a controversial issue if Fair Trade fish is going to be marketed as aproduct capable of improving fisher livelihoods. In this paper, we explore the role of middlemen in thefirst ever Fair Trade USA fishery: handline-caught yellowfin tuna from Molucca in Indonesia. Interviewswith fishers, middlemen, the local processor and those involved in Fair Trade implementation were con-ducted and analzed to understand changes to the organization of the value chain and of the communityby defining how middlemen contribute to the assets and capabilities of fishers. The results indicate thatmiddlemen contribute but also control the full range of assets required to enable fishers to fulfill theirvalue chain functions. Introduction of Fair Trade has facilitated a rapid reorganization of value chain struc-ture in the fishery with notable impacts on fisher perceptions of the resource and the market. However, itremains unclear what this value chain reorganization means for community structure. The opportunitiesand challenges for Fair Trade USA fish to be an empowering force depend heavily on fisher-middlemendynamics being adequately considered.
Sea cucumbers are invertebrates that have been marketed legally and illegally for years in Colombia. Little
is known of these species, and there is hardly any biological, ecological or market information on the
population of the species under commercial exploitation. We present information on the sea cucumbers of
the Caribbean coast of Colombia, with data on the fishery, fishermen, trade, species of interest, nutritional
contents and reproductive characteristics. We report new species for the Caribbean and conclude with the
importance of initiating a management plan for the Colombian fishery resource.
Low stock status of red king crabs Paralithodes camtschaticus in Bristol Bay prompted an industry initiative to reduce the minimum size limit for the commercial fishery from 165 mm in carapace width (CW) to 152 mm in CW. In terms of carapace length (CL), which is the metric used in data collection programs, this is equivalent to a reduction from 137 to 128 mm CL. The rationale was primarily to reduce potential nontarget handling mortality, which was suspected to contribute to the depressed stock status. Analysis of red king crab fishery observer data showed that the reduced size limit would initially increase catch rates of legals (under new size limit) by 10–41%, diminish total bycatch of nontarget red king crabs (sublegal and female crabs) by 9–33%, and reduce the fishing effort (pot lifts) needed to attain annual catch quotas by 2–27%. Yield-per-recruit analysis indicated that steady-state yield would decline 5–7% under the smaller size limit, assuming a 20% handling mortality rate. Size distributions of the catch would shift so that crabs of 128–136 mm CL would constitute 35% of the catch, yet the percentage of large males (>163 mm CL) in the spawning stock would barely increase from 6.1% to 8.2%. A population dynamics model revealed that there is a slightly higher probability of larger stock spawning biomass under the 128-mm-CL size limit than under the 137-mm-CL limit over a 50-year planning horizon. An economic break-even analysis showed that it takes 23 years for cumulative catch under the 128-mm-CL size limit to exceed cumulative catch under the 137-mm-CL size limit. At a 7% real interest rate, the reduced size limit takes 40 years to break even. Net benefits of the reduced size limit are larger and accrue more quickly if handling mortality rates are greater than 20%, whereas the reduced size limit never yields a positive economic benefit if handling mortality rates are 10% or less. The reduced size limit does not appear to be a cost-effective measure for red king crab resource conservation given likely values of handling mortality rates.
To advance economic and sustainability objectives in a lobster fishery, four broadly different management policies were evaluated: minimum and maximum size limits, constant catch quotas, and quota set yearly in proportion to the previous year’s CPUE. The performance of each policy was evaluated based on its discounted economic yield, together with egg production, catch, and catch stability. Maximum size limits performed poorly for all indicators. Raising the minimum size increased economic yield by improving yield-per-recruit. Output controls, both constant and dynamic, uniformly outperformed size limits, leading to substantially higher economic yield and egg production. A dynamic harvest control rule, setting quota in proportion to the previous year’s catch rate, achieved the highest economic yield, catch, and egg production over 20 years. The optimal (30%) exploitation rate under this policy produced a 182% improvement in economic yield compared to a baseline strategy of only minimum size, but led to a mean year-to-year change in quota of 11.5% in response to yearly variable recruitment. This quota-setting management regime is straightforward to implement, using only catch rate as input. When absolute exploitation rate estimates are not available, this quota-setting harvest control rule can be constructed using only a target level of effort.
Fish maws (dried swimbladders of fishes) are regarded as traditional luxurious delicacies, medicine and tonics, which have been recommended and consumed in Asia over many centuries. At the commercial level, they are ranked as different values based on species. However, fish maw species and the trade are still unknown and undocumented. The processing treatments make them difficult for species identification based on morphological characterization. In the present study, the genetic identification of the main commercialized species of fish maws has been carried out, based on the amplification of a fragment of mitochondrial 16S rRNA gene and subsequent BLAST analysis. The applicability of all kinds of processed products was verified, including dried, water soaked, salt fried and salt fried plus water soaked forms. The result indicated this method was applicable to all of them, showed that 53.3% of the products were incorrectly labeled and 58.3% of “croaker” products were substituted with catfish or perch species. Moreover, results indicated that besides traditional trade in Asia, the fish maw trade has been globally expanded to meet the growing demand of market. Therefore, this method can be useful in normative control of processed products, particularly in the authenticity of imported species, verifying the correct traceability in commercial trade, the correct labeling, and also for fisheries control of endangered species to conserve stocks biodiversity.
China is marked by rising levels of consumption, but also high levels of social distrust.
This paper offers an empirical study of luxury seafood consumption in banquets in
Beijing as a way of understanding perceptions of and responses to a lack of trust in
abstract social institutions in Chinese society. We focus on the chronic distrust Chinese
people have in the food system and the economic system. Governance of the food
system is marked by failures related to food safety and authenticity, while the formal
institutions of the economic system are insufficient to provide security in professional
contexts. Because people do not have social trust in the rationality and effectiveness of
such abstract institutions, they are compelled to generate personal trust. Luxury
seafood consumption in banquets is an important component of this process of
generating personal trust.
Tropical sea cucumber mariculture has potential to become a profitable industry and contribute towards natural population replenishment. Here, we synthesise the fields of progress, current impediments and research opportunities in tropical sea cucumber aquaculture arising from recent studies and an Indo-Pacific symposium.We present novel comparisons of data fromhatcheries, earthen ponds and sea pens from published and unpublished studies in various countries. Of the fewtropical species to have been cultured, only the sandfish Holothuria scabra has been bred extensively. While risks from hatchery-produced sea cucumbers are recognised, more genetic research is needed in farming and sea-ranching programmes. Advances have been made in the culture and nursery rearing of tropical sea cucumber juveniles but few have been published. Sandfish larvae have now been grown successfully on just one microalga species, but experimental studies to optimise culture conditions are needed urgently. Disease of tropical sea cucumbers in culture is infrequent but the treatment of disease and parasites is understudied. Earthen ponds are currently most effective for nursery rearing of juvenile sandfish to a size for stocking. Growth rates and survival of sandfish in ponds to market size are also favourable, and should improve via studies on stocking density, feeding regimes and pond management. Sea pens confer ownership of released stock and can provide a means of limiting predation in natural habitats but the costs of materials, maintenance and surveillance against poaching can diminish profitability. Sea ranching has minimal material costs but needs a large leased area and may require juveniles to be marked prior to release. Retail prices of sandfish in Hong Kong increased exponentially with body size. A cost-benefit analysis illustrated that labour and utility costs in pond farming will preclude profitability of monoculture in some cases, forcing proponents to look towards co-culture or gamble with uncertain survival in sea ranching. Better governance and consultation regarding the stocking of sea cucumbers have been advocated.Weconclude thatwell-designed experiments and meta-analyses are needed to fill critical knowledge gaps if sea cucumbermariculture is to expand in the tropics as it has in temperate Asia. Co-culture remains a burgeoning frontier despite poor success of initial studies. Sea cucumbers have superb potential to diversify mariculture industries in the tropics and potentially ameliorate the detrimental effects of mariculture on coastal ecosystems.
Age and growth analysis is essential to fisheries management. Indirect methods to calculate growth are widely used; however, length frequency data analysis in sea cucumbers is complicated by high data variability caused by body wall elasticity. Here we calculated Isostichopus badionotus parameters of the von Bertalanffy growth function. In order to address bias produced by body wall elasticity, we compared the performance of four measurements and one compound index that combines different biometric parameters: the square root of the length-width product (SLW). Results showed that variability in length data due to body wall elasticity was controlled by using body length (Le) from the SLW compound index. Growth in I. badionotus follows a negative allometric tendency. Slow or zero growth periods were observed during October and November, when weather conditions were adverse.
Distribution and density of two holothurian species in Cubagua Island, Venezuela. Holothurian populations in the Caribbean have been significantly depleted in some areas, and others are still in danger to satisfy international markets. In Venezuela, this marine resource has been illegally exploited since the early 1990s. To contribute with their management and protection, this work analyzed the distribution, abundance and population structure of two commercial holothurians Isostichopus badionotus and Holothuria mexicana in Cubagua Island shores. A total of 52 stations were studied around the island during the year 2008. Surveys included visits to each station, for which a band transect of 50m 2 with four replicates were carried out. The results show that I. badionotus has a higher distribution on the East coast of the island, and is found over Thalassia testudinum beds or bivalve molluscs aggregations, with an average density of 0.011ind/m 2 , C.I. 95%=0.005-0.017, n=122, and a general abundance estimated in 117ind/ha. H. mexicana has been practically depleted (0.001 ind/m 2 C.I. 95%=0.0002-0.0013, 7.7 ind/ha, n=8). We recommend the maintenance of the total ban adopted in 1997 to assure the protection of these species, mainly because no previous data supported the start of the fishery, and also, because the current densities are still very low when compared to other areas in Venezuela and the Caribbean. These are animals easy to catch, susceptible to overfishing, and with a very low recovery rate; thus, more control is required from the local authorities. Rev. Biol. Trop. 59 (2): 843-852. Epub 2011 June 01.
Market preferences of natural resources contribute to shape their exploitation and production. Beche-de-mer, the product after gutting, cooking, salting and drying sea cucumbers, is exported worldwide to Asian dried seafood markets. A better understanding of the trade, value and market preferences of Pacific island beche-de-mer could identify critical postharvest processing techniques and management strategies for fisheries and aquaculture. Data were collected on export prices and trade of beche-de-mer from Kiribati, Fiji, Tonga and New Caledonia, and the selling prices, respective sizes and organoleptic properties of the products in stores in China. Export prices varied considerably within and among the four countries and low-value species were the most exported by volume. Most of the beche-de-mer from the four Pacific islands is exported to Hong Kong, where quality products are sold and others are distributed to mainland China. Prices of the beche-de-mer in Chinese stores varied up to ten-fold and were mostly influenced by species, body size and, to a lesser extent, physical damage to the products. Market prices across species (averaging US$15-385 kg-1) appear to have mostly increased six- to twelve-fold over the past decade. The data allude that fisheries for Holothuria scabra, H. lessoni, H. fuscogilva, H. whitmaei and Thelenota ananas should be most carefully managed because they were the highest-value species and under greatest demand. The relationships between size of beche-de-mer and sale price were species specific and highly varied. This study also highlights the need for better regulations and/or enforcement of minimum size limits in sea cucumber fisheries, which can help to maximise economic benefits of wild stocks.
Extinction risk has been linked to biological and anthropogenic variables. Prediction of extinction risk in valuable fauna may not follow mainstream drivers when species are exploited for international markets. We use results from an International Union for Conservation of Nature Red List assessment of extinction risk in all 377 known species of sea cucumber within the order Aspidochirotida, many of which are exploited worldwide as luxury seafood for Asian markets. Extinction risk was primarily driven by high market value, compounded by accessibility and familiarity (well known) in the marketplace. Extinction risk in marine animals often relates closely to body size and small geographical range but our study shows a clear exception. Conservation must not lose sight of common species, especially those of high value. Greater human population density and poorer economies in the geographical ranges of endangered species illustrate that anthropogenic variables can also predict extinction risks in marine animals. Local-level regulatory measures must prevent opportunistic exploitation of high-value species. Trade agreements, for example CITES, may aid conservation but will depend on international technical support to low-income tropical countries. The high proportion of data deficient species also stresses a need for research on the ecology and population demographics of unglamorous invertebrates.
Groupers are a valuable fishery resource of reef ecosystems and are among those
species most vulnerable to fishing pressure because of life history characteristics
including longevity, late sexual maturation and aggregation spawning. Despite their
economic importance, few grouper fisheries are regularly monitored or managed at
the species level, and many are reported to be undergoing declines. To identify major
threats to groupers, the International Union for Conservation of Nature (IUCN) Red
List criteria were applied to all 163 species. Red List assessments show that 20 species
(12%) risk extinction if current trends continue, and an additional 22 species (13%)
are considered to be Near Threatened. The Caribbean Sea, coastal Brazil and
Southeast Asia contain a disproportionate number of Threatened species, while
numerous poorly documented and Near Threatened species occur in many regions.
In all, 30% of all species are considered to be Data Deficient. Given that the major
threat is overfishing, accompanied by a general absence and/or poor application of
fishery management, the prognosis for restoration and successful conservation of
Threatened species is poor. We believe that few refuges remain for recovery and that
key biological processes (e.g. spawning aggregations) continue to be compromised by
uncontrolled fishing. Mariculture, through hatchery-rearing, increases production of
a few species and contributes to satisfying high market demand, but many such
operations depend heavily on wild-caught juveniles with resultant growth and
recruitment overfishing. Better management of fishing and other conservation efforts
are urgently needed, and we provide examples of possible actions and constraints.
How can species be exploited economically to extinction? Past single-species hypotheses examining the economic plausibility of exploiting rare species have argued that the escalating value of rarity allows extinction to be profitable. We describe an alternative pathway toward extinction in multispecies exploitation systems, termed 'opportunistic exploitation'. In this mode, highly valued species that are targeted first by fishing, hunting, and logging become rare, but their populations can decline further through opportunistic exploitation while more common but less desirable species are targeted. Effectively, expanding exploitation to more species subsidizes the eventual extinction of valuable species at low densities. Managers need to recognize conditions that permit opportunistic depletion and pass regulations to protect highly desirable species when exploitation can expand to other species.
The abundance, distribution, size, structure, nutritional quality and feasibility of exploitation of a sea cucumber population, an alternative fishery resource for Banco Chinchorro (Mexican Caribbean) were evaluated. Sampling was conduced during the three main climatic seasons: rainy (September 1998), cold front (December 1998) and dry (April 1999). Five sampling sites were chosen to cover the three major habitats: seagrass (north, central), reef patches (north, south), and shallow sandy-bottoms. Three species and a hybrid were identified: Holothuria thomasi, H. mexicana, H. floridana, and H. floridana × H. mexicana. H. floridana was the most abundant (mean density = 0.12 ind m −2). Growth and natural mortality parameters, and maximum sustainable yield (MSY), were estimated using simplified protocols commonly predicated for the assessment of tropical fisheries, all assuming equilibrium conditions. Banco Chinchorro was hit by Hurricane Mitch following the first survey; estimated abundance during the second survey (after the hurricane) was only 14% of the pre-hurricane survey. Based on this study case we discuss (1) the shortcomings of methods assuming equilibrium, (2) the need for specific life-history data, and (3) the research opportunities provided by the response of populations to natural disturbances or to harvesting.
Worldwide, most sea cucumber fisheries are ineffectively managed, leading to declining stocks and potentially eroding the resilience of fisheries. We analyse trends in catches, fishery status, fishing participation and regulatory measures among 77 sea cucumber fisheries through data from recent fishery reports and fishery managers. Critical gaps in fisheries biology knowledge of even commonly targeted species undermine the expected success of management strategies. Most tropical fisheries are small-scale, older and typified by numerous (>8) species, whereas temperate fisheries are often emerging, mono-specific and industrialized. Fisher participation data indicated about 3 million sea cucumber fishers worldwide. Fisher participation rates were significantly related to the average annual yield. permanova analysis showed that over-exploited and depleted fisheries employed different sets of measures than fisheries with healthier stocks, and a non-metric multidimensional scaling ordination illustrated that a broad set of regulatory measures typified sustainable fisheries. SIMPER and regression tree analyses identified that the dissimilarity was most related to enforcement capacity, number of species harvested, fleet (vessel) controls, limited entry controls and rotational closures. The national Human Development Index was significantly lower in countries with over-exploited and depleted fisheries. Where possible, managers should limit the number of fishers and vessel size and establish short lists of permissible commercial species in multispecies fisheries. Our findings emphasize an imperative to support the enforcement capacity in low-income countries, in which risk of biodiversity loss is exceptionally high. Solutions for greater resilience of sea cucumber stocks must be embedded within those for poverty reduction and alternative livelihood options.
This study examined the sea cucumber industry in the Philippines through the value chain lens. The intent was to identify effective pathways for the successful introduction of sandfish culture as livelihood support for coastal communities. Value chain analysis is a high-resolution analytical tool that enables industry examination at a detailed level. Previous industry assessments have provided a general picture of the sea cucumber industry in the country. The present study builds on the earlier work and supplies additional details for a better understanding of the industry’s status and problems, especially their implications for the Australian Center for International Agricultural Research (ACIAR) funded sandfish project “Culture of sandfish (Holothuria scabra) in Asia- Pacific” (FIS/2003/059).
This paper presents an overview of the key characteristics of small-scale coastal marine fisheries in Latin America and the Caribbean as well as an examination of some of the weaknesses, gaps, and challenges faced in fisheries assessment and management within the region. The information here is based largely on discussions involving a range of scientists, managers and fishers at the first CoastFish conference (“Coastal fisheries in Latin America and the Caribbean”) held in Merida, Mexico in 2004 and literature review. Small-scale fisheries in this region, as elsewhere, share similar characteristics including multi-gear and multispecies, low capital and labour intensive, remote landing sites, large number of migrant and seasonal workers, and weak market and bargaining power among fishers. Common issues facing these fisheries are resource overexploitation, complex and dynamic fleet interactions, competition and conflicts between fleets (small-scale, industrial and recreational), and post-harvest problems, such as lack of infrastructure. Research in the region focuses mainly on biological–ecological aspects, with limited attention paid to socio-economic issues. Collection of catch data is common in most countries, at least for the main target species, but its reliability has been questioned in many cases, especially when a multi-species fishery is in place. Management tools frequently used are ‘input control’, e.g., size limit, gear restriction, closed season, closed area, and fishing permits. Finally, legal frameworks typically exist to regulate fisheries in most countries, but lack of success in management could be attributed to a lack of surveillance, weak institutions, unclear legal management instruments, and limited involvement of fishers in the management process. Based on the above, we discuss ways to address gaps and challenges in the assessment and management of small-scale fisheries in Latin America and the Caribbean.
The first standardized, global assessment of these fishes, using Red List criteria, reveals threatened species needing protection.
We developed a species-specific PCR method to identify species among dehydrated products of 10 sea cucumber species. Ten reverse species-specific primers designed from the 16S rRNA gene, in combination with one forward universal primer, generated PCR fragments of ca. 270 bp length for each species. The specificity of the PCR assay was tested with DNA of samples of 21 sea cucumber species. Amplification was observed in specific species only. The species-specific PCR method we developed was successfully applied to authenticate species of commercial products of dehydrated sea cucumber, and was proven to be a useful, rapid, and low-cost technique to identify the origin of the sea cucumber product.
An important contemporary driver of livelihood change in coastal Southeast Asia is the growing demand for luxury seafood in China. Based on fieldwork in the municipality of Balabac in Palawan province, western Philippines, this paper takes stock of this trend, and investigates the implications of the relationship between Chinese patterns of luxury seafood consumption and the intensification of coastal livelihoods in Southeast Asia. The paper focuses mostly on the trade in live reef fish, with reference also to sea cucumber and shark fin. In the light of recent discussions of social and environmental change in Southeast Asia, the paper addresses how the intensification of coastal livelihoods has manifested in important trends, including an increasing reliance on high-value commodity fisheries such as the trade in luxury seafood. Important consequences of this intensification of coastal livelihoods include environmental degradation, and social change due to the development of broader trading networks. The paper argues that the live reef fish for food trade is an important contemporary livelihood that highlights the ways in which Chinese consumption is having diverse social and environmental consequences for source countries in Southeast Asia.
This study investigates the dried seafood trade, centred in Chinese markets, in order to better understand the pressures its demand exerts on global marine resource stocks. Using Hong Kong, the region's largest entrepôt, as a focal point, the trade in shark fins, abalone, bêche-de-mer and dried fish is characterized in terms of product history, volume, source fisheries and species composition. Trends identified in the Hong Kong market are interpreted in the context of the larger Chinese market. Shark fin imports grew 6% per year between 1991 and 2000, most likely because of market expansion in Mainland China, posing increasingly greater pressures on global shark resources. In contrast, the quantities of dried abalone traded through Hong Kong remained steady, but inferences based on this trend are discouraged by suggestions of increasing preferences for fresh product forms and growing domestic production in Mainland China. Hong Kong's imports of dried bêche-de-mer (sea cucumber) have decreased, while the percentage of imports re-exported has remained steady, suggesting that Hong Kong continues as an entrepôt for Mainland China despite declining domestic consumption. Few conclusions can be drawn regarding dried fish products, including whole fish and fish maws, because of a lack of product differentiation in customs data, but a market survey was conducted to provide information on species composition. Comparison of Hong Kong dried seafood trade statistics to those of other key trading partners indicates that, in general, Hong Kong's duty-free status appears to encourage more accurate reporting of traded quantities. Under-reporting biases ranged from 24 to 49% for shark fin and bêche-de-mer, respectively. Comparison to United Nations (UN) Food and Agriculture Organization (FAO) databases indicates additional under-reporting for shark fin such that an alternative minimum estimate of world trade is at least twice the FAO estimates in 1998–2000. The results of a survey of Hong Kong traders provide insight into their attitudes toward harvest, economic and regulatory factors, and suggest that conservation efforts are unlikely to emerge from, or be actively supported by, dried seafood trade organizations. The market's apparent sensitivity to economic sentiment, however, reveals an opportunity for consumer education to play a role in shaping future market growth and resource conservation. Recommendations are provided for improving trade statistics and for developing better analytical techniques to complement traditional methods for monitoring the exploitation and management of fisheries resources.
The harvest of blue crabs Callinectes sapidus in Chesapeake Bay declined 46% between 1993 and 2001 and remained low through 2008. Because the total market value of this fishery has declined by an average of US $ 3.3 million per year since 1993, the commercial fishery has been challenged to maintain profitability. We developed a bioeconomic simulation model of the Chesapeake Bay blue crab fishery to aid managers in determining which regulations will maximize revenues while ensuring a sustainable harvest. We compared 15 different management scenarios, including those implemented by Maryland and Virginia between 2007 and 2009, that sought to reduce female crab harvest and nine others that used seasonal closures, different size regulations, or the elimination of fishing for specific market categories. Six scenarios produced the highest revenues: the 2008 and 2009 Maryland regulations, spring and fall closures for female blue crabs, and 152- and 165-mm maximum size limits for females. Our most important finding was that for each state the 2008 and 2009 scenarios that implemented early closures of the female crab fishery produced higher revenues than the 2007 scenario, in which no early female closures were implemented. We conclude that the use of maximum size limits for female crabs would not be feasible despite their potentially high revenue, given the likelihood that the soft-shell and peeler fisheries cannot be expanded beyond their current capacity and the potentially high mortality rate for culled individuals that are the incorrect size. Our model results support the current use of seasonal closures for females, which permit relatively high exploitation of males and soft-shell and peeler blue crabs (which have high prices) while keeping the female crab harvest sustainable. Further, our bioeconomic model allows for the inclusion of an economic viewpoint along with biological data when target reference points are set by managers.
Information theory and log-likelihood models - a basis for model selection and inference practical use of the information theoretic approach model selection uncertainty with examples Monte Carlo insights and extended examples statistical theory.
This study presents a historical review, a meta-analysis, and recommendations for users about weight–length relationships, condition factors and relative weight equations. The historical review traces the developments of the respective concepts. The meta-analysis explores 3929 weight–length relationships of the type W = aLb for 1773 species of fishes. It shows that 82% of the variance in a plot of log a over b can be explained by allometric versus isometric growth patterns and by different body shapes of the respective species. Across species median b = 3.03 is significantly larger than 3.0, thus indicating a tendency towards slightly positive-allometric growth (increase in relative body thickness or plumpness) in most fishes. The expected range of 2.5 < b < 3.5 is confirmed. Mean estimates of b outside this range are often based on only one or two weight–length relationships per species. However, true cases of strong allometric growth do exist and three examples are given. Within species, a plot of log a vs b can be used to detect outliers in weight–length relationships. An equation to calculate mean condition factors from weight–length relationships is given as Kmean = 100aLb−3. Relative weight Wrm = 100W/(amLbm) can be used for comparing the condition of individuals across populations, where am is the geometric mean of a and bm is the mean of b across all available weight–length relationships for a given species. Twelve recommendations for proper use and presentation of weight–length relationships, condition factors and relative weight are given.
The reproductive status of the holothuroid species Isostichopus badionotus (Selenka, 1867) and Holothuria mexicana (Ludwig, 1875) was studied over 16 months in Bocas del Toro (Panama), from November 1999 to February 2001. Sexual reproduction was evaluated by the gonad index method, and by histology of gonad development. In addition, population structure was assessed based on sex ratio, minimum reproductive size, and length and weight distributions of males and females. The sex ratio in both species was 1:1, with a unimodal population distribution composed mainly of mature individuals. The minimum reproductive length and weight were 13-20 cm and 150 g, respectively, for both species, although reproductive individuals 10 cm in length were also found. A consistently higher gonad index was observed in H. mexicana, due to a high proportion of mature females and males and high gonad indices in most monthly samples. Gametogenesis and spawning patterns seemed to occur throughout the year, with periods of enhanced activity. Two periods of maximum reproductive activity were tentatively identified: July-November for I. badionotus and February-July for H. mexicana, but neither species had a single, sharply defined annual spawning event. Further work on these exploited holothuroids should examine the relationships between reproduction and environmental factors and between reproductive status and recruitment.
Baseline assessment of virgin biomass of sea cucumbers in Old Providence and Santa Catalina. Western Caribbean. SPC Beche-de-Mer Inf
- H Hoike
- P Usseglio
- F Ramos
Hoike, H., Usseglio, P., Ramos, F., 2015. Baseline assessment of virgin biomass of
sea cucumbers in Old Providence and Santa Catalina. Western Caribbean. SPC
Beche-de-Mer Inf. Bull. 35, 42-49.
Evaluation of sea cucumber fishing in Puerto Rico
- P Miguel
- K Morgan
- I Vlasac
- N Yuhas
Miguel, P., Morgan, K., Vlasac, I., Yuhas, N., 2013. Evaluation of sea cucumber fishing
in Puerto Rico. Worcester Polytechnic Institute Worcester, MA, p. 78.
Sea cucumbers: A global review of fisheries and trade. FAO Fisheries and Aquaculture Technical Paper No
- V Toral-Granda
Toral-Granda, V., 2008. Population status, fisheries and trade of sea cucumbers in
Latin America and the Caribbean. In: Toral-Granda, V., Lovatelli, A., Vasconcellos,
M., (Eds.) Sea cucumbers: A global review of fisheries and trade. FAO Fisheries
and Aquaculture Technical Paper No. 516, Rome, pp. 211-229.