Showing papers on "Shrimp published in 1980"

Structural components of eelgrass (Zostera marina) meadows in the lower Chesapeake Bay—Decapod crustacea

Abstract: Otter trawl collections of eelgrass habitats in the lower Chesapeake Bay during 1976–1977 produced 14 species of decapod crustaceans. These collections were dominated by palaemonid shrimp (Palaemonetes spp.), blue crabs (Callinectes sapidus), and sand shrimp (Crangon septemspinosa), each of which exhibited unimodal seasonal abundance curves with large summer peaks. Decapod abundance was positively correlated with plant biomass throughout the year. Decapod densities on vegetated bottoms were greater than on unvegetated bottoms, and nighttime abundance on each bottom type was greater than corresponding daytime abundance. Total decapod abundances in Chesapeake Bay eelgrass meadows appear to be much greater than those reported in North Carolina eelgrass or Gulf of Mexico turtlegrass habitats.

Grazing and predation of the grass shrimp Palaemonetes pugio1

Abstract: The grass shrimp Palaemonetes pugio did not significantly car sume live sea grass (Halodule wrightii), but assimilation of the attached epiphytes was quite significant. Salinity changes from ll-33%0 had no effect on the amount of epiphytes assimilated but increasing the temperature from 14”-30°C exponentially increased the epipliyte consumption rate. The assimilation rate per unit body weight declined significantly for shrimp ranging from 6 to 54 mg dry weight (1 l-24-mm total length). Total assimilation of epipl ytes increased with shrimp size up to 25-30 mg, after which it leveled off or declined. Assimilation efficiencies averaged about 83% and were not affected by changes in temperature and salinity. Small shrimp (11-15 mm) did not prey on mysids but larger mes (19-22 mm) did. The maximum consumption rate was six mysids per shrimp per day and was attained at a mysid density of about 400*m-2. HaZoduZe without epiphytes did not provide a refuge for the mysids, but the addition of epiphytes as an alternative food significantly reduced the predation pres

Life history relationships between the bopyrid isopod Probopyrus pandalicola and one of its freshwater shrimp hosts Palaemonetes paludosus.

Abstract: Data are provided on the reproduction, attachment, postlarva! development and population structure of the parasitic isopod, Probopyrus pandalicola, on its shrimp host, Palaemonetes paludosus, collected monthly for 2 years from a site in the Wakulla River and a tributary, McBride's Slough, Wakulla Co, Florida Ovigerous P pandalicola occurred from January to October, whereas ovigerous hosts occurred only from January to September Brood size, which ranged from 350-11,850 young, increased exponentially with length of the female, and was independent of host sex Mean brood size and length of ovigerous P pandalicola increased from late winter to a peak in March There was a second smaller peak in June with a subsequent decline to low levels for the remainder of the breeding season Cryptoniscus larvae occurred on shrimp 9-39 mm long from April-October Growth of body width in relation to body length in male and female isopods was positively allometric The length of female and male parasites was positively correlated with the length of the host and female parasite, respectively Host and parasite longevity was ca 1 year Death of the parasite rarely preceded host death These data are compared with that for other epicaridean isopods

Seasonal abundance and distribution of crangon franciscorum and palaemon macrodactylus (decapoda, caridea) in the san francisco bay-delta

Abstract: Two decapod shrimp, Crangon franciscorum and Palaemon macrodactylus, donuinate the epifaunal community of the western Sacramento-San Joaquin Delta. The Franciscan bay shrimp, C. franciscorum, once supported an extensive com niercial fishery in San Francisco Bay ( Bonnot, 1932) and today supports a more restricted bait fishery. It is a conumon inhabitant of the continental shelf and estuaries from southeastern Alaska to California ( Schmitt, 1921 ) . Israel (1936) discussed the life luistory of C. franciscorum in the San Francisco Bay-Delta region and Ganssle ( 1966) provided additional qualitative information on its distribution and abundance in Suisun Bay. Recent studies have investigated aspects of the physiology and tolerance of C. franciscoruni to various environmental factors (Khorranu and Knight, 1977 ; Sharp et al., 1978 ; Nelson et ci., 1979) but little information is available on the biology of C. franciscoruni in the Bay-Delta. The oriental shrinup, Palaemon i'nacrodactylus, is thought to have been intro duced into the San Francisco Bay Estuary in the early 1950s from water-ballast tanks of ships returning fronu Korea ( Newman, 1963) . Its presence in San Francisco Bay is thought to represent its northernmost distribution on the west coast of North Anuerica. Little is presently known about the biology of the oriental shrimp in the Bay-Delta systenu. C. franciscoruni and P. macrodactylus are inuportant components of the estuarine food web, especially as food for the game fish of the estuary (Ganssle, 1966). These shrinup are also inuportant predators of the opossum shrimp, Neomysis niercedis, (Siegfried et al., 1978 ; Sitts, 1978) and nuay be important in nutrient cycling in the estuary ( Nelson et al., 1979) . Information on potential interactions between the native specinuens of C. franciscorum and the introduced specimens of P. macrodactylus is lacking.

Microbiological quality of frozen shrimp and lobster tail in the retail market.

Abstract: The microbiological quality of three frozen shrimp products and frozen lobster tail at the retail level was determined. The number of retail units of the four products examined and the geometric means for aerobic plate counts at 30 and 35 degrees C, respectively, were: 1,464 units of cooked, peeled shrimp--13,000 and 7,200 per g; 1,468 units of raw, peeled shrimp--860,000 and 300,000 per g; 1,300 units of raw, in-shell shrimp--800,000 and 300,000 per g; 1,315 units of lobster tail--140,000 and 42,000 per g. Geometric means for coliform, Escherichia coli, and Staphylococcus aureus counts for all products were < 10 per g.

Use of Grass Shrimp in Toxicity Tests

Abstract: The literature pertaining to the use of grass shrimp in toxicity testing is reviewed. Information on the life history, species differences, collection, culture, handling, effects of toxicants, standard methods for toxicity testing, and potential problems in experimental design is presented. Suggestions for future research are made.

Apparatus and method for rearing shrimp

Abstract: An apparatus and method for rearing shrimp through the larvae stage wherein the shrimp are subjected to controlled conditions and a common enclosure for the male and female adult shrimp is provided which permits uncontrolled access of the shrimp to one another and wherein the shrimp are maintained through a plurality of cycles of mating, spawning and hatching. The system is further provided with filtration means for filtering the medium of the common enclosure and with collecting means for collecting hatched shrimp at preselected times from the common enclosure medium as the medium moves into the filtration means.

Effect of Lysozyme and Sodium EDTA on Shrimp Microflora

Abstract: The influence of lysozyme and salts on the growth of the microflora of shrimp was investigated. It was found that lysozyme at concentrations up to 150 μg/ml could retard microbial growth in nutrient broth at 28°C. Growth of shrimp microflora was not affected much at low concentrations (0.05% and 0.1%) of EDTA but was totally inhibited in the presence of 0.5% Na2EDTA. No growth was discernible using concentrations of 50 μg/ml lysozyme and 0.02% Na2EDTA, either in nutrient broth or in 2% shrimp homogenate.

The disposition of aromatic hydrocarbons in adult spot shrimp (Pandalus platyceros) and the formation of metabolites of naphthalene in adult and larval spot shrimp.

Abstract: 1. Adult spot shrimp (Pandalus platyceros) exposed to 110 p.p.b. (μg/l) of the water-soluble fraction of Prudhoe Bay crude oil for one week accumulated a variety of lowmolecular weight aromatic hydrocarbons (primarily C1-C5 substituted derivatives) in thoracic and abdominal tissues.2. Adult and larval spot shrimp were exposed to 3H- and 14C- labelled naphthalene (a component of the water-soluble fraction) in seawater to delineate the types of metabolites formed. Both adults and larvae converted naphthalene to conjugated and non-conjugated structures such as the glucuronide, sulphate, dihydrodiol and phenolic derivatives. The presence of a quinone was also indicated.

Application of a bio-economic-engineering model for shrimp mariculture systems

Abstract: The culture of marine invertebrates, collec- Williams). Previous economic studies involving tively termed mariculture, has received much penaeid shrimp mariculture, although directed attention as a new and potentially lucrative toward an immediate need and research goal, industry. Much research has been devoted to have failed to consolidate biological, economic, molluscs (oysters, clams, and mussels) and and engineering relationships and principles crustaceans (shrimp, crawfish, crabs, and lob- into a comprehensive model capable of sters) (Bardach, Ryther, and McLarney). In performing analyses on an unlimited number particular, effort has been directed to the de- of system designs and a continuum range of velopment of a technologically and commer- facility sizes. cially feasible penaeid shrimp mariculture Computerized models designed for applicascheme (Broom; Mock and Murphy; Neal and tion in technological assessment and determinLatapie; Parker and Conte; Wheeler). Results ing direction of future research in aquaculture of extensive research efforts show promise have been developed for other systems (Allen that the technological feasibility of penaeid and Johnston; Polovina; Schurr, Allen, and shrimp farming in Gulf coastal regions of the Botsford). Though biologically oriented in United States is near to being a reality. terms of the output generated and audiences Before significant commercial investment in addressed, these models demonstrate a clear shrimp mariculture will be realized, however, step foward in analytical power in the direction economic relationships in addition to technical of assessing the status of economic feasibility. considerations must be better understood. In- Therefore, considering the purposes, applicavestors will initially want to know the vital tions, and limitations of previous modeling biological and environmental elements of a studies in aquaculture and the status of the shrimp culture system and how variability in industry, we see a distinct need for a modeling those elements affects production. Investors tool which will consolidate biological, economic, will also want to know how much control can and engineering relationships and principles. A be exercised over these critical elements and at model of this scope is needed to provide a what cost. For penaeid shrimp mariculture to framework applicable to most land-based maribecome an attractive commercial investment, culture operations. The more extensive analythese questions must be answered and the sis of this type of model will aid the potential potential economic feasibility of such opera- mariculturist (as well as creditors) in allocating tions must be established and readily de- financial resources and assessing investment monstrable to potential investors and creditors opportunities. More specifically, because during their decision-making process. shrimp mariculture is a growing new investEconomic, investment, and feasibility ment opportunity with high risk, economies of analyses have been performed on a variety of size need to be identified. That information will aquacultural systems other than penaeid enable an investor or creditor to identify the shrimp mariculture (Gibson and Wang; size of system that captures most of the econoHerrick and Baldwin; MacDonald, Meade, and mies of size and thus to keep risk capital as low Gates; Roberts and Bauer; Shang; Shang and as possible. Like previous modeling efforts, Fujimura; Smith). Studies of shrimp maricul- this type of model will also provide guidelines ture have been limited to itemizing fixed and for the direction of future research and assessvariable costs and calculating per units costs ment of advancing technology. of production for a given system or limited We describe the development of a bio-ecorange of system sizes. Financial analyses have nomic-engineering (BEE) model for penaeid been performed on given hypothetical opera- shrimp mariculture and its application to a tions defined by a rigid set of assumptions specific system. The tool is introduced in pri(Anderson and Tabb; Phillips and Gillespie; marily an application context. 1

Observations on the life history of the belted sandfish, Serranus subligarius (Serranidae)

Abstract: The biology of Serranus subligarius, a typical inhabitant of low limestone reef outcroppings and artificial reefs from North Carolina to Florida and in the northern Gulf of Mexico, was studied on inshore jetties in the northeastern Gulf of Mexico from February 1974 to April 1975. The length-weight relationship was expressed by the equation W = 0.000006L3.431. Growth was greatest in the first year (43.5 mm SL) and declined in the remaining three years of life (17.3, 10.5, and 7.1, respectively). In individuals larger than 40 mm SL, gammaridean and caprellid amphipods were the most numerous food items but crabs, shrimp, and fishes were the most important food items by weight. In individuals less than 40 mm SL, copepods were the most numerous food item, but gammaridean amphipods and shrimp were the most important items by weight. Two incidents of cannibalism were recorded. The ovotestis of the belted sandfish is composed of two lobes which are broadly united posteriorly, with the testicular tissue restricted to a broad band encircling the posterior region of the gonad. Age-group 1 fish are functional synchronous hermaphrodites. Testicular tissue matures in the fall or winter of a fish's first year (all specimens examined histologically, including those from the nonspawning season, contained flagellated spermatozoa) while ovarian tissue matures in the following spring. Spawning season in 1974 extended from late April or early May to September. Crossfertilization is the usual reproductive mode, although individuals are capable of selffertilization.

Seasonal and Diel Activity Variations in the Shrimp Palaemon adspersus from a Brackish, Non-Tidal Area

Abstract: Seasonal and diel activity rhythms of the natantian shrimp Palaemon adspersus Rathke from a non-tidal area were investigated in the laboratory by means of photocells. P. adspersus is nocturnal, with maximum activity levels in summer and early autumn, and minimum levels in winter and early spring. When the nights are short the activity consists of 1 brief, intense period; it extends to 2-3 periods when the nights are prolonged. The change from 2 to 1 activity periods is very sharp at the end of April. The total length of the active period was 10 h per 24 h throughout the year. Length of active perlod and subdivision into smaller periods is considered to be regulated by an endogenous mechanism. Seasonal variations in activity levels are correlated to migratory behaviour in the field and to the reproductive cycle.

Impact of mesh size reduction of trawl nets on the prawn fishery of Kakinada in Andhra Pradesh

Abstract: Since 1967 routine monitoring studies on the prawn fisheries was undertaken and, of late especially from 1977 onwards it was noticed that relatively smaller prawns of the conventional species as well as adults of the tiny shrimp Acetes started appearing regularly in the trawl catches in considerable quantities. This has prompted an analysis of the prawn catches of the area in relation to the mesh sizes of the nets operated and the results are reported here.

Method of treating fresh shrimp to reduce moisture and nutrient loss

Abstract: Fresh shrimp are stored in flake or crushed ice containing a moisture binding phosphate from the time that they are harvested until they are processed, including both aboard the fishing vessel and in the processing plant. An effective amount of sodium tripolyphosphate, Na 3 P 5 O 10 is admixed to water as it is delivered to an ice making machine. The treated ice and the shrimp are introduced together into a storage receptacle. The ice melts as it cools the shrimp, to in that manner bring the moisture binding phosphate into contact with the shrimp meat. It is preferred to use flake ice which contains about one to two percent (1.0-2.0%) by weight of sodium tripolyphosphate, Na 3 P 5 O 10 .

Correlations of allozymic variation with habitat parameters using the grass shrimp, palaemonetes pugio.

Abstract: The grass shrimp, Palaemonetes pugio, is ubiquitous in Atlantic and Gulf Coast estuaries. It occupies a wide range of habitats which differ in permanence and accessibility to migration. The larvae are planktonic (Knowlton and Williams, 1970). The adults prefer bodies of water with low current velocities (Antheunisse et al., 1972). Reproduction stops and population numbers drop in the winter. Reproduction begins in early spring when the first of two or more generations of the year are produced (Wood, 1967). On and near Galveston Island this shrimp occurs along the shoreline throughout the estuarine system and in isolated brackish ponds. It is impossible to accurately compute the sizes and ages of the grass shrimp populations used in this study, so we have employed inferential methods of estimating them. We predict positive rank order correlations between measures of population size and age and the genic variation in each population. In addition, populations from the estuarine system should be more variable than populations from ponds because they are more accessible to immigrants.