The Blue Crab Fishery in Mississippi

Analysis of 670 trawl, seine and marsh net samples collected from July 1971 through June 1973 provided data on the distribution and abundance of blue crabs in Mississippi Sound. Highest average catches were associated with salinities between 5.0 and 15.0 ppt (parts per thousand) and temperatures between 20.0 and 25.0oC. Young crabs congregated in dredged navigational channels and in the marshes that fringe the bays and coastline. Maximum numbers were captured over soft mud bottoms. Peak numbers of zoeae occurred in the summer and fall. Megalopae were collected in all months. Early crab stages appeared throughout the year. Width-frequency distributions suggested rapid growth. Crabs tagged and released in Lake Borgne, La. during the fall of 1971 moved into Mississippi Sound in the vicinity of Cat Island to overwinter. Recoveries of crabs released in the St. Louis Bay, Biloxi Bay and Pascagoula River estuarine systems indicated little movement between estuaries during the spring and summer. Identified parasites included a new microphallid trematode. Commercial landings of blue crabs averaged 1,712,000 pounds for the 20-year period 1953-1972. Catch per unit of effort (pounds/pot day) was low during the spring and fall, peaking in the summer. Rises in the catch per unit of effort closely followed the migration of female crabs into Mississippi Sound

The Blue Crab Fishery in Mississippi

Analysis of 670 trawl, seine and marsh net samples collected from July 1971 through June 1973 provided data on the distribution and abundance of blue crabs in Mississippi Sound. Highest average catches were associated with salinities between 5.0 and 15.0 ppt (parts per thousand) and temperatures between 20.0 and 25.0oC. Young crabs congregated in dredged navigational channels and in the marshes that fringe the bays and coastline. Maximum numbers were captured over soft mud bottoms. Peak numbers of zoeae occurred in the summer and fall. Megalopae were collected in all months. Early crab stages appeared throughout the year. Width-frequency distributions suggested rapid growth. Crabs tagged and released in Lake Borgne, La. during the fall of 1971 moved into Mississippi Sound in the vicinity of Cat Island to overwinter. Recoveries of crabs released in the St. Louis Bay, Biloxi Bay and Pascagoula River estuarine systems indicated little movement between estuaries during the spring and summer. Identified parasites included a new microphallid trematode. Commercial landings of blue crabs averaged 1,712,000 pounds for the 20-year period 1953-1972. Catch per unit of effort (pounds/pot day) was low during the spring and fall, peaking in the summer. Rises in the catch per unit of effort closely followed the migration of female crabs into Mississippi Sound

A New Microphallid Trematode from the Blue Crab in the Northern Gulf of Mexico

Levinseniella (Monarrhenos) capitanea n. sp. is described from metacercariae on the hepatopancreas and gonads of Callinectes sapidus Rathbun from Louisiana and Mississippi. It can be distinguished from all other members of the genus by possessing 11–21 atrial pockets and an acetabulum larger than the oral sucker, not possessing a pharynx nor well-developed ceca, and being 1.9–3.6 mm in length. Heardlevinseniella Yamaguti, 1971 is considered a synonym of Levinseniella Stiles & Hassal, 1901

A New Microphallid Trematode from the Blue Crab in the Northern Gulf of Mexico

Levinseniella (Monarrhenos) capitanea n. sp. is described from metacercariae on the hepatopancreas and gonads of Callinectes sapidus Rathbun from Louisiana and Mississippi. It can be distinguished from all other members of the genus by possessing 11–21 atrial pockets and an acetabulum larger than the oral sucker, not possessing a pharynx nor well-developed ceca, and being 1.9–3.6 mm in length. Heardlevinseniella Yamaguti, 1971 is considered a synonym of Levinseniella Stiles & Hassal, 1901

Observations on the Distribution and Seasonality of Portunid Megalopae in Mississippi Coastal Waters

Observations on the distribution and seasonality of common coastal portunid megalopae are presented. Callinectes sapidus megalopae were abundant from May through November. The megalopae of C. similis, though present throughout the year, peaked in numbers from February through April. With the exception of January, Portunus spp. megalopae occurred in all months, with maximum numbers collected in April. Callinectes sapidus megalopae commonly occurred at all stations, whereas, the megalopae of C. similis and Portunus spp. appeared to be limited by salinity

Blue Crab Larval Dispersion and Retention in the Mississippi Bight

A conceptual hypothesis relating physical forcing to dispersion and retention was developed for blue crab larvae within the Mississippi Eight. The spawning period for blue crabs in the northern Gulf of Mexico is protracted. Hatching of eggs occurs near the barrier islands and mouths of coastal bays from March through October. Larvae are released on ebbing tides and spend the next 30 to 50 d offshore where they develop through seven zoeal stages before undergoing metamorphosis to megalopae. Duration of the megalopal stage is variable but generally persists from 6 to 20 d. Blue crabs recruit to Gulf estuaries as megalopae. During the critical planktonic phase in their life history, larvae are subject to the vagaries of seasonal circulation patterns which can either return them to nearshore where they can successfully settle, or lose them at sea. Archived currents from a 3-dimensional, primitive equation, sigma-coordinate model of the Gulf of Mexico, driven by climatological winds and damped to surface salinity and temperature, were used to study advection of blue crab larvae in the Mississippi Eight. Data suggest that seasonal circulation patterns driven by average wind stress provide a window of opportunity for blue crab larval dispersion offshore and return nearshore during the appropriate period in their development for settlement as megalopae. in the Mississippi Eight, this window usually occurs between April and October. Large basin-scale events, such as Loop Current intrusions and spin-off eddy generation, may interrupt this circulation pattern and change the settlement success rate. Variations in the seasonal forcing, due to anomalous winds, or basin-scale events may contribute to fluctuations in levels of harvestable adult blue crabs

Effects of 1973 Floodwaters on Plankton Populations in Louisiana and Mississippi

Studies to assess the impact of floodwater diversion on plankton populations in coastal waters of Mississippi and Louisiana were conducted from 23 April 1973 through 13 July 1973. Fixed stations in Lake Pontchartrain, Lake Borgne and western Mississippi Sound were sampled once in April, twice in May and June, and once in July. Stations in Terrebonne Parish, Louisiana were visited once in May, June and July. Data are presented on changes in the species composition of zooplankton subsequent to the opening of the Bonnet Card and Morganza floodways. The hydrographic conditions at the time of sampling are discussed

First Recorded Observance of the Dinoflagellate Prorocentrum minimum (Pavillard) Schiller 1933 in Mississippi Sound and Adjacent Waters

The present paper documents the occurrence of the dinoflagellate Prorocentrum minimum in Mississippi Sound and adjacent coastal waters. Outbreaks of discolored water are attributed to blooms of P. minimum in February 1977 and in January and February 1981. Data are presented on the seasonality of the organism in St. Louis Bay. Observations on water appearance and a descriptive analysis of the cells are presented for the 1981 blooms

Records of Deep-Water Chaetognaths from the Northern Gulf of Mexico

Fourteen species of deep-water Chaetognatha were present in plankton samples collected between 200 and 677 m at five stations along the continental slope of the northem Gulf of Mexico. Samples were taken in conjunction with the MARFlN Geryon cruises of 1987 and 1988. New Gulf of Mexico records resulting from this study were Eukrohnia calliops, Eukrohnia proboscidea, Mesosagitta sibogae, and Sagitta megalophthalma. Other deepwater species present were Eukrohnia fowleri, E. bathypelagica, E. bathyantarctica, Caecosagitta macrocephala, Mesosagitta decipiens, M. minima, Solidosagitta planctonis, Krohnitta subtilis, Flaccisagitta hexaptera, and F. lyra. In addition, the normally epiplanktonic taxa, Pterosagitta draco, Serratosagitta serratodentata, and Sagitta bipunctata occurred in some of the samples

Effects of 1973 Floodwaters on Plankton Populations in Louisiana and Mississippi

Studies to assess the impact of floodwater diversion on plankton populations in coastal waters of Mississippi and Louisiana were conducted from 23 April 1973 through 13 July 1973. Fixed stations in Lake Pontchartrain, Lake Borgne and western Mississippi Sound were sampled once in April, twice in May and June, and once in July. Stations in Terrebonne Parish, Louisiana were visited once in May, June and July. Data are presented on changes in the species composition of zooplankton subsequent to the opening of the Bonnet Card and Morganza floodways. The hydrographic conditions at the time of sampling are discussed