Shrimp Research Articles

Vulnerability of marine resources affected by a small-scale tropical shrimp fishery in Northeast Brazil

Abstract Tropical fisheries tend to be multispecies and require management approaches adapted to high diversity but scarce and poorly informative data. Productivity and Susceptibility Analysis-PSA is particularly useful where catch or biological data are incomplete, aggregated across species or insufficient for quantitative stock assessment. We applied PSA to estimate vulnerability and potential risk to target and non-target species caught by the small-scale shrimp fishery in northeast Brazil, adapting the method to regional conditions and incorporating an assessment of uncertainties caused by its subjective choices. Our findings suggest that non-target species can be more vulnerable than target ones. Bagre marinus, Pseudobatos percellens, Micropogonias furnieri, Hypanus guttatus, Macrodon ancylodon, Polydactylus virginicus, Rhizoprionodon porosus, Cynoscion virescens, Larimus breviceps, and Menticirrhus americanus, were the top 10 species potentially at risk due to their low productivity (long lifespans, low spawning), high capture rates of juveniles and overlap of feeding and breeding grounds with fishing areas. Most species (76%) maintained the same risk category (low, moderate, or high) regardless of the score weighting or productivity and susceptibility attribute boundaries applied. Overall, the target species are not currently the main ones threatened, but bycatch such as elasmobranchs, catfishes and Scianidae should be prioritized for assessment and data collection.

Bycatch of Asteroidea from shrimp trawl fishery in the southwestern Atlantic Ocean – Brazil

Shrimp trawling is considered a significant negative impact on the marine ecosystem, especially on the benthic community. Sea stars (Echinodermata: Asteroidea) are one of the most affected groups by unintentional catches. This study was performed at the Santana Archipelago, a Marine Protected Area in the northern region of Rio de Janeiro State, between 2008-2009. Sea stars accidentally caught by trawling were collected during open and closed season of the shrimp fisheries (Xiphopenaeus kroyeri) at depths of 5-60 m. A generalized linear zero-inflated model was applied to test for differences in capture between fishing seasons and depths. A total of 158 sea star specimens were captured. These specimens were identified as Asterina stellifera, Astropecten acutiradiatus, Astropecten brasiliensis, Astropecten cingulatus, Luidia alternata alternata, Luidia clathrata, Luidia ludwigi scotti, Luidia senegalensis. The sea stars A. brasiliensis and L. senegalensis are currently considered as vulnerable species in the Brazilian official list of threatened species. The higher capture of sea stars was shown in deepest areas, and there was no significant difference in the number of specimens between seasons. This is the first study about asteroids accidentally captured by shrimp trawling.

Stock Assessment and Rebuilding of Two Major Shrimp Fisheries (Penaeus monodon and Metapenaeus monoceros) from the Industrial Fishing Zone of Bangladesh

The two economically important shrimp species in Bangladesh are the tiger shrimp, Penaeus monodon, and the brown shrimp, Metapenaeus monoceros. However, a continuous decline in the landing of these species from the industrial trawling made it critical to assess their stock biomass status to explore their response to the present degree of removal. Given the minimum data requirement and robustness, this study employed the depletion-based stock reduction analysis (DB-SRA) to assess these fisheries rigorously. For the industrial fishing zone (beyond the 40 m depth in the EEZ of Bangladesh), the estimated historic mean carrying capacity (K) was 5015 metric tons for the Penaeus monodon and 35,871 metric tons for Metapenaeus monoceros. The estimated overfishing limits (OFL), which were much smaller than the reported catches throughout the time series, indicate the overfishing status of these fisheries. As a result, the estimated biomass for the reference year (B2020) for both species was lower than BMSY, indicating that these fisheries are not producing MSY. Therefore, for the rebuilding and sustainable management of these stocks, this study recommended a catch limit of 100 metric tons for P. monodon and 750 metric tons for M. monoceros for the next ten years from biomass projections.

A Superior Contiguous Whole Genome Assembly for Shrimp (Penaeus indicus)

Penaeid shrimp fishery and culture is a commercial enterprise contributing to employment, nutritional security and foreign exchange of developing countries. The genetic improvement programs being operated in shrimp benefit hugely from genomic resources. We report here a high-quality genome assembly for a penaeid shrimp, Penaeus indicus, which is the only Crustacean assembly to meet the reference standards of 1 and 10 Mb N50 lengths for contigs and scaffolds, respectively, among genomes of >1.5 Gb assembly length. The assembly is 1.93 Gb length (34.4 Mb scaffold N50) with 28,720 protein-coding genes and 49.31% repeat elements. The P. indicus assembly has 31.99% of simple sequence repeats, the highest among sequenced animal genomes. In comparison to other shrimp genomes having short contig lengths, the P. indicus assembly has 346 un-gapped contigs of over 1 Mb length and betters other shrimp genomes on sequence contiguity. This contiguous genome revealed 15,563 coding single nucleotide polymorphisms (SNPs) of which 2,572 are non-synonymous. The assembly and the SNP data resources have applications to genetic improvement programs, evolutionary studies and stock management.

Prediction of the distribution of shrimp species found in southern Benin through the lake Nokoué-Ocean complex

The export of shrimps to the European Union was one of the mainstays of the Beninese economy. It is an income-generating activity for the populations living along Lake Nokoué. The lack of a fisheries management strategy has caused a drastic decline in shrimp’s production in Lake Nokoué since 2003. To remedy this problem, it is necessary to hypothesize on their spatial-temporal dynamics in the Lake Nokoué-Cotonou channel complex. This is investigated by combining a literature review on their life cycles and habitat suitability with spatial-temporal evolution of salinity obtained from in-situ observations. The literature review reported four (04) potential families of shrimp species whose part of their life cycle is common to the ecology of Lake Nokoué: Penaeidae (Penaeus); Palaemonidae (Macrobrachium); Atyidae (Atya) and Desmocarididae (Desmocaris). The overall results in relation to the life cycle of the shrimp species indicate that adults of the Macrobrachium, Atya species have a favorable environment in Lake Nokoué from August to November and their larvae must remain in the lake from December to June to ensure their survival. The species of the genus Desmocaris, which carry out their entire life cycle in fresh water, can stay in Lake Nokoué from August to November. The species of the genus Penaeus have a favorable environment in Lake Nokoué from December to June but their larvae can only survive in the sea. Species of the genus Caridina (freshwater) and Palaemon (estuary and marine) belonging to the family Palaemonidae can however be found in Lake Nokoué because of their wide distribution on the West African coast although they are not reported in Benin. This research makes it possible to predict the presence or absence of shrimp genera in a lake system, based on their life cycle. Based on the results obtained, we suggest a ban on fishing in Lake Nokoué between December and February and a ban on shrimp fishing in the Cotonou canal for a good management of the shrimp stock in Benin.

The fishery of pelagic shrimp aviú Acetes paraguayensis in eastern Brazilian Amazon

The pelagic shrimp, Acetes paraguayensis Hansen, 1919, is an ecologically important species with an enormous socioeconomic value for the human populations in the regions where it occurs. This species also has considerable potential for shrimp farming, although few details are known of its biology. This study investigated the artisanal exploitation of A. paraguayensis stocks in the northern Brazilian municipality of Santarém over 16 months, focusing on the types of equipment most used to harvest of this shrimp, the fishing dynamics, and production patterns. The matapi trap was the principal method used of harvesting A. paraguayensis in the study region, conforming to a typically artisanal, small-scale fishing production system. This study results provide an essential research tool for developing conservation and management strategies and the eventual establishment of farming protocols.

Dietary overlap of carcharhinid sharks in the Gulf of Papua

Assessing the feeding patterns of sharks provides insight into ecological interactions. Three coastal sharks are common by-catch in the Gulf of Papua prawn fishery in Papua New Guinea. The diets of Carcharhinus coatesi (n = 122), Rhizoprionodon acutus (n = 83) and Rhizoprionodon taylori (n = 177) were assessed using stomach content analysis. Teleosts, crustaceans and molluscs were the main prey. Percentage frequency of occurrence (%FO) and percentage frequency by number (%N) were computed to describe dietary compositions. Non-metric multidimensional scaling and Morisita Index determined the level of feeding overlap. Rhizoprionodon taylori was a generalist feeder having the broadest diet, R. acutus was the most selective feeder, preying predominantly on teleosts and C. coatesi consumed the greatest proportion of crustaceans that increased with size. The pairwise ANOSIM tests showed significant difference in dietary compositions of R. acutus and R. taylori (P = 0.1%, R = 0.318) and R. acutus and C. coatesi (P = 0.1%, R = 0.589), which indicate potential resource partitioning. Further work should aim to adequately characterise diets, improve prey identification and investigate spatial and temporal resource use patterns. Understanding ecological processes informs ecosystem approaches fisheries management.

Isopod parasite influences prawn responsiveness and activity

Most bopyrid isopod parasites, which are crustaceans themselves, settle in the branchial chamber of decapod crustaceans and feed on host haemolymph. Here we report the results of an experiment on the common prawn Palaemon serratus and the parasite Bopyrus squillarum. Infected and uninfected prawns were stimulated with pokes of a plastic rod until an escape response was triggered; the number of pokes was recorded as an indicator of prawn responsiveness, whereas the time spent moving following stimulation was used as an indicator of prawn activity. Our results show that bopyrid infection affects both prawn responsiveness and activity, with infected prawns requiring more pokes to move, and moving for less time compared to uninfected prawns. In nature, such behavioural changes may impact defence mechanisms and survival of infected prawns. This could contribute to decreases in P. serratus abundance, thereby affecting the coastal ecosystems home to this species and the fisheries reliant on it, such as the Irish shrimp fishery.

Effects of re-specifying the Northern Prawn Fishery bioeconomic model to include banana prawns

The Northern Prawn Fishery (NPF) is one of Australia’s most valuable federally managed fisheries. It has also been a focus for modelling in Australia, with over 40 years of development of bioeconomic, stock assessment and management strategy evaluation models that have been used to varying degrees to inform management. The current management model has been in operation for over 10 years and is used to set the total allowable effort (TAE) for the tiger prawn (Penaeus semisulcatus and P. esculentus) component of the fishery, historically undertaken after a mid-year closure. The success of management has resulted in increased stocks of tiger prawns, and a fishery before the mid-year closure during which fishing for banana prawns was historically the main activity. While the current management model includes the consequences of fishing for tiger prawns during the first season in terms of which weeks are available for fishing for tiger prawns when estimating the TAE, the lack of explicit inclusion of banana prawns in the bioeconomic modelling has resulted in concerns that the TAE may be biased, as effort is allocated in the model to tiger prawns that, in reality, should be applied to banana prawns. The current model was consequently extended to include an explicit banana prawn component, and a range of scenarios undertaken to explore the impact of this on the management advice. It was found that the current model overestimates the optimal level of effort to be applied to tiger prawns except during periods of very low banana prawn abundance. Banana prawns, which vary substantially inter-annually due largely to environmental drivers, were also found to be the key driver of the level of overall fishery profit, suggesting that greater attention to this component of the fishery may be necessary to achieve the objective of maximizing net economic returns from the NPF.

Evaluation of Post-Harvest Procedures for Quality Enhancement in the Louisiana Commercial Shrimp Industry

ABSTRACT The Louisiana commercial shrimp fishery has faced numerous challenges, and the number of fishermen is declining at an alarming rate. The opportunity may exist to add value to the industry by creating a superior product through optimal operating procedures. Post-harvest processes of plate freezing were analyzed to develop a high-quality shrimp product capable of fostering economic growth for fishermen. Sulfite-free melanosis prevention testing used 4-hexylresorcinol treatments in combination with vacuum-packing and modified atmosphere packing to delay the onset of black spot. The physical and chemical properties of plate frozen shrimp were analyzed from collaborating fishermen. Results found 4-hexylresorcinol products successfully inhibited black spot development for up to 10 days. Vacuum-packing and modified atmosphere packing did not have significant effects on melanosis inhibition. The use of plate freezers both onboard and at docks has the potential to improve shrimp quality, as well as advance the economic stability of the industry.

Towards Shrimp Resources Investment in Iraq water

The article highlighted the global importance and production of shrimp resources, whether it’s coming from the fisheries or from the aquaculture sector as well as it’s economy attribute in the international trade. Furthermore, it’s recognizing the status of the shrimp fishery in the marine and inland waters of Iraq, and the main negative factors impacted and reducing the shrimp stocks. Apparently no practical attempt has already been undertaken to culture the shrimp in the area, despite the availability of diverse water bodies. In conclusion, there is a great opportunity to developing the shrimp resources sector in Iraq by: (1) introduction and developing shrimp culture, (2) improving better management system for the shrimp fisheries.

Socioeconomic study for the wealth of marine shrimp in the territorial sea of Iraq

The present study was designed to investigate the contribution of shrimp fisheries and the related activities to the economy Iraq. For this purpose a socioeconomic information and data were collected for one year (2014) period. Three marine penaeid shrimps were constituted the majority of shrimp fisheries in Iraqi marine water, these are: Penaeus semisulcatus, Metapenaeus affinis and Parapenaopsis styliferus. University of Basrah institutes basically the Marine Science Center, apparently is the marine institute implemented researches and studies on shrimp landing have been recorded at Al Nasser fishing Society of the Basrah / Faw city. On the other side, the study concluded that any real and accurate data on shrimp landing can be only obtained from fisherman on the fishing boat of the field. In fact the marine fishing area of Iraq is very limited and the investigation shows that there are nearly 150- 250 fishing boats, 450 – 600 fisher man and 70 – 110 fishmonger contributing in the shrimp sector. However, their economy doesn’t restricted on shrimp, but, usually cornering other fish resources.The results revealed that, the increasing of anthropological activities, overfishing, high by catch, the degradation of natural habitats such as coastal mudflats and Marshes and pollution are the basic factors reducing the shrimp stocks. For best monitoring and data collection of the shrimp resources, a networking information and data collection system is provided.

Spatial and temporal effects improve Bayesian price estimation for the small-scale shrimp fishery in Sergipe State, Brazil

Local shrimp productivity and economic infrastructure may vary among small fishery communities, which can lead to unequal conditions for fishers. Consequently, the domestic market value for shrimp landing can be different and decentralized in space and time. Small-scale fisheries (SSF) have several characteristics, including the spatial and temporal interactions, which add uncertainty to fishery statistics. Bayesian hierarchical models allow parameters to vary on several levels using random effects or other means of randomization, which leads to better estimation of multilevel uncertainty compared to other methods. This study tests the influence of space and time on shrimp production prices in Sergipe State, Brazil, using a Bayesian hierarchical modelling approach. We also tested whether there is a relationship between capture per unit effort and production value. We described landings of Litopenaeus schmitti and Xiphopenaeus kroyeri in 27 locations in the State of Sergipe between 2010 and 2016. Shrimp production (kg) remained relatively stable (200–300 ton/year). Using the Bayesian approach, we found that prices of both species varied among landing points within and between years, and this variation has spatial and temporal dependence. The model enhanced our understanding of which factors affect price variability in landings. In particular, our models indicated that catch per unit of effort, location, and time affected the price variability in coastal landings within the State of Sergipe. However, the seasonal monthly effects were not as important as the yearly effects, since the variance within years was found to be low. This could indicate that economic activities (tourism) do not play an important role for shrimp prices in this region. Yet, biological factors (abundance and reproduction period) can affect the prices for some locations. Improving the estimates by using methods that can account for the human dimension of fishing activities is paramount in its management, enhancing the decision-making process.

Endogenous catch per unit effort and congestion externalities between vessels in a search‐matching model: Evidence from the French Guiana shrimp fishery

AbstractThis paper aims at explaining the recent rise in profits in the French Guiana shrimp fishery (FGSF) despite the overall fall in activity observed between 1990 and 2009. We develop a stochastic search‐matching version of the usual Cobb–Douglas bioeconomic fishery model. In this version catch per unit effort becomes endogenous, decreasing in the ratio of empty vessels to escaped fish, which we call “anthropic pressure” and which is determined by standard profit maximization. We first estimate the stochastic harvest function, which exhibits nearly constant returns to scale. We then show that a decrease in equilibrium anthropic pressure and congestion between vessels may be more than compensated by the consecutive rise in catch per unit effort. This leads to a fall in average harvesting costs and thus, to a rise in profits. In addition, we identify the condition under which a search‐matching fishery, working under open access, could reach a maximum economic yield equilibrium, which corresponds to a very particular case. Finally, the model makes it possible to evaluate the actual catch per unit effort and explain how the FGSF changed over the period considered with the help of the open access and maximum economic yield frameworks.

PRAWN FISHERY OF RIVER GANGA AROUND PATNA

Macrobrachium, the large freshwater prawns and some of its species viz., Macrobrachium rosenbergii, M. malcolmsonii and M. gangeticum, form the commercial fisheries and are in great demand. Macrobrachium gangeticum and M. malcolmsonii and other economic varieties of prawns are available in Ganga, Hooghly and Brahamputra river systems. However, the main prawn fishery in the Ganga near Patna is composed of M. gangeticum and M. malcolmsonii (Prasad and Kanaujia, 2006). Unfortunately, as a consequence of over-fishing, water pollution (Tripathy, 1982; Prakash and Agarwal, 1985) construction of barriers (Jhingran and Ghosh, 1978) and lift irrigation complexes, production of these prawn species has considerably declined in last decades from Patna and stretch above Patna. Now prawns are not available year around, except from May to October. The present communication evaluates the fishery and seasonal abundance of the prawn species in the Ganga near Patna by evaluating the landing data at three stations viz., Gandhisetu, Alamganj and Bashghat, (appro. 12 km stretch) for two year

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

Bioactivity of the Protein Hydrolysates Obtained from the Most Abundant Crustacean Bycatch.

The animals from bycatch of the shrimp fisheries can be a source of natural products and bioactive compounds. Thus, the present study aimed to evaluate the bioactivity of protein hydrolysates prepared from the two most abundant crabs from the bycatch of shrimp fisheries in Brazil (Callinectes ornatus and Hepatus pudibundus). Samples of C. ornatus and H. pudibundus were collected in the region of Ubatuba, State of São Paulo, Brazil. Muscles with small pieces of exoskeleton of both species were hydrolyzed using two enzymes, Alcalase 2.4 L® or Protamex®. The in vitro antioxidant capacity was analyzed used three methods: DPPH, sulfhydryl groups, and peroxyl radicals. Additionally, the cytotoxicity of the hydrolysates was investigated using pre-osteoblasts cells. The results showed that the degree of hydrolysis (DH) of H. pudibundus was superior to DH of C. ornatus using both enzymes and was higher when using the enzyme Alcalase 2.4 L® (32.0% ± 1.9). The analysis suggested that the hydrolysates have antioxidant activity. Besides that, no cytotoxic effect was observed on cell viability. Thus, protein hydrolysates of C. ornatus and H. pudibundus have bioactivity, which add value to these bycatch species and suggests their potential use as nutraceutical ingredient in the food industry.

The diet of Mustelus schmitti in areas with and without commercial bottom trawling (Central Patagonia, Southwestern Atlantic): Is it evidence of trophic interaction with the Patagonian shrimp fishery?

The study compares the diet composition between juveniles and adults of the narrownose smooth-hound Mustelus schmitti in areas with and without commercial bottom trawling using stomach contents. Individuals (n = 291) were caught as by-catch by the bottom-trawl shrimp fishery and by coastal sport anglers in Central Patagonia (Southwestern Atlantic between 43° and 45° S). Results showed that M. schmitti is a mesocarnivorous with a mean trophic level of 3.58. The diet was based mostly on crustaceans (decapods, stomatopods, isopods and amphipods), polychaetes, fishes and cephalopods, in a decreasing order of importance. The diet varied between juveniles and adults, and between individuals captured by the trawling fishery and sport anglers. Crabs were the main prey item observed in the stomach of individuals caught by anglers while the shrimp Pleoticus muelleri was the most consumed prey by individuals caught as by-catch. Juveniles consumed more polychaetes than adults, while the latter consumed mostly shrimp. The presence of shrimp in stomach contents of M. schmitti caught by the commercial fishery is evidence of a trophic interaction between M. schmitti and the fishery. The interaction may be due to the shark and the fleet targeting the same resource, or due to the shark using the discarded shrimp as a food source.

Reproductive biology of the shorthead drum Larimus breviceps (Acanthuriformes: Sciaenidae) in northeastern Brazil

The shorthead drum Larimus breviceps is one of the main bycatch species of the shrimp fisheries in Brazil. However, studies addressing the biology and fisheries impacts on this species are still scarce. Here we describe the main aspects of the reproductive biology and the female gonadal development of L. breviceps on Paraíba, northeast Brazil. The reproductive tract was described by macroscopic and microscopic analysis. The ovaries were composed by oogonia, pre-vitellogenic, vitellogenic, mature, and atretic oocytes. A total of 970 individuals (549 females and 421 males) were caught between December 2016 and November 2017 through beach seining. The total length (TL) varied from 4.2 to 23.0 cm. Females dominated over males (1 female: 0.77 male). The length–weight relationship did not differ between the sexes, presenting a positive allometric growth. The following stages were thus defined for females: immature, initial development, advanced development, mature, and regressing. The period of highest reproductive activity occurs between November and March and immature individuals occur throughout the year. Mean length at first maturity (L50) was estimated as 11.1 cm TL. The information provided here contributes to the overall knowledge of this species and may be helpful for further development of management practices that ensure the sustainability of marine species exploitation.

Assessment of the stock status of two penaeid shrimps in the Northeastern Brazil Marine Ecoregion and implications for their management

Shrimp fisheries is one of the most profitable fishery activities in tropical regions, highlighting the need of assessing the status of those resources more thoroughly. Then, this study aimed to provide a comprehensible stock assessment of two highly exploited marine penaeid shrimps (Xiphopenaeus kroyeri and Penaeus schmitti) in two important fishing grounds within the Northeastern Brazilian Marine Ecoregion (NBME) in the state of Alagoas. In addition, the hypothesis of different stocks between areas is also tested by checking for possible between-area heterogeneity in population parameters. We found remarkably similar patterns of growth and mortality between the two fishing grounds for both species, with homogeneous parameters indicating an absence of regional structuration. Then, the two fishing grounds contain a single stock for both species, which will respond similarly to the same fishing pressures and management scenarios. We also indicate that the seabob shrimp is close to the limit of full exploitation in both regions based on Yield per Recruit analysis. Meanwhile, the white shrimp is overexploited in one of them. Potential management tools to allow sustainable and productive exploitation in these fisheries are effort control and spatial restrictions to conserve nursery habitats and maintain sustainable rates of population growth.