Identification of Vibrio spp. causing vibriosis in spiny lobsters (Panulirus homarus L.) in Bengkulu marine temporary shelter ponds

Spiny lobster (Panulirus homarus) is one of the export commodities of the Indonesian fisheries subsector and an important component for shrimp fisheries in Indonesia. In the development of lobster cultivation, there are several obstacles, the presence of vibriosis infection caused by the pathogenic Vibrio bacteria. This study aimed to identify Vibrio spp. bacteria in spiny lobsters (P. homarus) reared in the marine cultivation ponds, Bengkulu, Indonesia. Clinical symptoms of lobsters infected with vibriosis are red spots on the uropod, pleopod, and abdominal parts. Bacterial isolation was conducted by isolated some internal organs in spiny lobsters, that are, gills, stomachs, haemolymph, and hepatopancreas. The result showed there are 5 isolates of Vibrio bacteria that coded by IN3, ST2, HA1, HP2, and HP3. These bacteria isolates were identified through their colony morphology and biochemical tests. Characterization on the Thiosulfate Citrate Bile Salt Sucrose (TCBS) medium showed that lobsters were infected with Vibrio species. Based on Bergey’s Manual of Determinative Bacteriology, Austin and Austin, the identification results showed that HA1 isolate was identified as Vibrio algynolyticus, IN3 isolate was identified as V. anguillarum, ST2 was identified as V. ordalii, HP2 in first lobster was identified as with V. algynolyticus that mostly in the hepatopancreas, and HP3 was identified as V. splendidus

Fish and Fisheries

As the cause of dead zones became understood, research was devoted to figuring out the impact of hypoxia on aquatic life. The Gulf of Mexico dead zone overlaps with the Fertile Fisheries Crescent that stretches from Alabama to Texas, home to a multibillion dollar seafood industry. The chapter argues that the effect of hypoxic waters on benthic invertebrates is clear, while the story for mobile species like fish is complicated. Sessile invertebrates on the bottom, food for many fish and other animals, are wiped out when dissolved oxygen disappears. This chapter explains that even when mobile organisms are able to swim away to oxygen-rich waters, they are concentrated into a smaller habitat where they are more easily caught by predators and fishers. In the Gulf, the effects of hypoxia on fisheries are difficult to separate from the response of the fishing industry and overfishing, but effects especially on shrimp fisheries have been documented. As the chapter summarizes, hypoxia has many other impacts on aquatic biota, including rearranging food webs and contributing to the rise of jellyfish in coastal waters. Even when fishing yields are not affected, dead zones can devastate aquatic life and habitats.

Local Ecological Knowledge Networks in Tropical Artisanal Shrimp Fisheries

BackgroundLocal ecological knowledge (LEK) in fishing communities is generated through interactions between fishers and the exploited resources. It is transmitted through social networks, interdisciplinary structures that drives the dynamics of socio-ecological systems (SES). LEK variability is supposed to depend on the quality and quantity of ecological information flow among different stakeholders. To assess what is driving LEK themes, we hypothesized that the formation of LEK clusters among fishers is determined by network articulation, fisher experience and the commercial value of the exploited species. MethodsThe study area comprises three fishing communities in the Western South Atlantic, in the tropical coastal zone of Brazil where artisanal shrimp fisheries (on Penaeus schmitti, P. subtilis and Xiphopenaeus kroyeri) are a major activity. Data collection took place between March, April, and November 2019. To test our hypothesis, linear regression and bipartite network analyses were performed to visualize the interactions between fishermen groups and LEK themes. The connectivity, nesting, modularity, and centrality parameters in this social network were calculated to test the hypothesis. ResultsOur results indicate that experienced fishers enhance LEK in their networks on the themes of food, mortality, and growth. Furthermore, there are subgroups of fishers with dissimilar knowledge about the exploited shrimp species, one old on the fishery with wide knowledge, other less experienced, just knowing about reproduction and migration themes. ConclusionWe conclude that there is a spatial similarity in the connectivity of fisher’s LEK, mainly concerning the reproductive and migratory dynamics of the target species, but also differences permeated by fishers’ experience and local interests. Managers initiating co-management agreements using reproduction and migration referential variables as benchmarks will be more successful if they incorporate LEK into decision-making. Regional knowledge similarities favor the implementation of management policies at a regional scale potentially reducing conflicts within fishing communities and increasing resource use efficiency.

Crustaceans as Fisheries Resources: General Overview

Much of the biological and other research efforts on crustaceans have been driven by their importance to humans as a food source. Production comes from a diverse array of methods and scales of extraction, from small recreational or subsistence fisheries to industrial-scale operations. Most crustacean catch comes from shrimp fisheries, with over two million tons taken in 2014, mainly by trawl. The genera Acetes, Fenneropenaeus, and Pandalus account for around three quarters of this catch. Crab, krill, and lobster are the other main crustacean products (around 600,000 t crab, 380,000 t krill, and 300,000 t lobster in 2014). Trends in crustacean fisheries are broadly similar to those of other seafood, although crustaceans often target different market segments and receive higher prices than fish. Crustacean fisheries management faces many challenges with management of bycatch from trawl gears especially significant. Fortunately, crustaceans tend to be easily handled with low discard mortality, and this has enabled widespread use of regulations based on size, maturity, or sex (e.g., male-only fisheries). Total allowable catch (TAC) limits are widely used and highly effective for ensuring sustainable harvests when set responsibly using good information. TAC systems are often combined with catch share or individual transferable quota systems, which had a mixed history in crustaceans, sometimes reducing overall community benefit. This parallels the challenge facing fisheries globally of ensuring that harvests are not only sustainable but also deliver benefits to the wider community beyond the commercial fishers; management of some crustacean fisheries is at the forefront of these developments.

Shrimp Fisheries

Shrimp are a much desired and nutritious food product with a high economic value: capture-biomass ratio. The most important shrimp fisheries take place in marine habitats and are dominated by estuary-dependent “warm-water” species of penaeid and sergestid shrimps. Fishing with otter and beam trawls accounts for the major part of shrimp production, as these gears target species that form large schools over relatively level open ocean bottoms. Bycatch and discard of nontarget species are a particular problem of shrimp trawling, which disrupts bottom communities and removes juveniles of ecologically and commercially important finfish. The destructive effect of heavy trawls on the open soft-bottom habitats of most important species is not as severe as in other fisheries, given the rapid recovery of soft-bottom communities. Management of shrimp fisheries to prevent both growth and recruitment overfishing is based on models incorporating variables such as measures of growth, mortality, and climatic factors. Fishing efforts can be controlled by limiting access (e.g., number of fishers, vessels) and regulating seasonal closures of fishing grounds. Although there are signs of overfishing in some shrimp populations, the short life cycle (one to two years) with the rapid growth of major shrimp species makes them relatively resilient to overfishing. Conflicts between aquaculture and shrimp fisheries include economic competition and the biological impacts of shrimp aquaculture on natural shrimp populations. Protection and restoration of coastal wetlands, which serve as shrimp nurseries, are vital to the future of shrimp fisheries.

Update on crustaceans known from the Amazonian continental shelf and adjacent oceanic areas

The major biodiversity on the planet is present in coastal and oceanic environments, despite this, on the northern continental shelf of Brazil, data on most of the marine groups still are deficient, especially in areas deeper than 20 m and in the continental slope area. This lack of data is aggravated by high fisheries exploitation, which causes a decline in large, abundant populations, even leading them to threat of extinction. Among that marine biodiversity, no group has a larger morphological variety than crustaceans. In this scenario, knowledge about the local biodiversity, its richness and seasonality, is essential for a qualified fisheries management. The Amazon continental shelf has one of the largest shrimp fisheries in the country, and due to the ecological and economic importance that crustaceans have in the region, a detailed study on their diversity is necessary. In this article, we use data collected in the Revizee Program. We identified 91 species: crabs (32.97%), shrimp (28.57%), anomurans (10.99%), soft crabs (10.99%), lobsters (9.89%), stomatopods (4.40%) and isopods (2.20%). The State of Amapá had fewer species () compared to Pará (). The data analysis shows there is a lack of knowledge about the real biodiversity present on the Amazon continental shelf.