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Full-Text Articles in Life Sciences

Comments On "On The Utility And Disutility Of Jebar" - Reply, Mark A. Cane, Vladimir M. Kamenkovich Aug 1999

Comments On "On The Utility And Disutility Of Jebar" - Reply, Mark A. Cane, Vladimir M. Kamenkovich

Faculty Publications

No abstract provided.


Age And Growth Of Cobia, Rachycentron Canadum, From The Northeastern Gulf Of Mexico, James S. Franks, James R. Warren, Michael V. Buchanan Jul 1999

Age And Growth Of Cobia, Rachycentron Canadum, From The Northeastern Gulf Of Mexico, James S. Franks, James R. Warren, Michael V. Buchanan

Faculty Publications

We examined 1005 cobia, Rachycentron canadum, from recreational catches in the northeastern Gulf of Mexico from 1987 to 1995. Specimens ranged from 325 to 1651 mm fork length (FL); females had a mean FL of 1050 mm (n=730) and were significantly larger than males that had a mean FL of 952 mm (n=275). The over all male to female ratio was 1:2.7. Ages of 565 cobia were estimated from thin-sectioned otoliths (sagittae). Marginal-increment analysis of sagittal otoliths showed a single annual minimum during June. Male cobia (n=170; 525-1330 mm FL) ranged from age 0 to 9, and females (n=395; 493-1651 …


Blue Crab Larval Dispersion And Retention In The Mississippi Bight, Donald R. Johnson, Harriet M. Perry Jul 1999

Blue Crab Larval Dispersion And Retention In The Mississippi Bight, Donald R. Johnson, Harriet M. Perry

Faculty Publications

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 …


Local Data Assimilation In The Estimation Of Barotropic And Baroclinic Open Boundary Conditions, Igor Shulman, James K. Lewis, John G. Mayer Jun 1999

Local Data Assimilation In The Estimation Of Barotropic And Baroclinic Open Boundary Conditions, Igor Shulman, James K. Lewis, John G. Mayer

Faculty Publications

The problem of data assimilation in the specification of open boundary conditions for limited area models is addressed in this paper. Optimization approaches are detailed, which are based on combining available data on an open boundary with the physics of the hydrodynamical model. In our case the physics is in terms of the flux of energy through the open boundary. These optimized boundary conditions, for both barotropic and baroclinic situations, interpreted physically as special Linearizations of the Bernoulli equation for each normal mode. Because of the complexity of decomposing variables into normal modes for open boundaries with varying bathymetry, we …


The Winogradsky Column & Biofilms: Models For Teaching Nutrient Cycling & Succession In An Ecosystem, Delia Castro Anderson, Rosalina V. Hairston Jun 1999

The Winogradsky Column & Biofilms: Models For Teaching Nutrient Cycling & Succession In An Ecosystem, Delia Castro Anderson, Rosalina V. Hairston

Faculty Publications

No abstract provided.


Particle Fluxes During Austral Spring And Summer In The Southern Ross Sea, Antarctica, Vernon L. Asper, Walker O. Smith Jr. Mar 1999

Particle Fluxes During Austral Spring And Summer In The Southern Ross Sea, Antarctica, Vernon L. Asper, Walker O. Smith Jr.

Faculty Publications

The flux of particles from the euphotic zone through 200 m was investigated on the Ross Sea continental shelf during two cruises, the first in November-December 1994 and the second in December 1995 and January 1996. An assessment of surface layer phytoplankton biomass and productivity was made simultaneously. Particle flux was measured using floating sediment traps whose collection efficiency was assessed rigorously. Phytoplankton biomass and productivity increased rapidly in November-December, and biomass was maximal in mid-December. Thereafter productivity appeared to decline substantially. Biomass declined as well, but mot as rapidly as productivity. Vertical flux rates were low early in the …


Gulf Estuarine Research Society Spring 1999 Meeting Abstracts Jan 1999

Gulf Estuarine Research Society Spring 1999 Meeting Abstracts

Gulf and Caribbean Research

Meeting abstracts from the Spring 1999 meeting of the Gulf Estuarine Research Society.


Recent Trends In Water Clarity Of Lake Pontchartrain, J.C. Francis, M.A. Poirrier Jan 1999

Recent Trends In Water Clarity Of Lake Pontchartrain, J.C. Francis, M.A. Poirrier

Gulf and Caribbean Research

An analysis of Secchi disk transparency observations from 3 sites on the Lake Pontchartrain Causeway indicates that water clarity has increased at the north shore and mid-lake sites, but has not changed at the south shore site. Louisiana Department of Environmental Quality data from 1986 through 1995 were used in the analysis. Further analysis indicates that the increased transparency was not caused by changes in salinity or wind speed. The best explanation for the observed increase is the cessation of shell dredging in 1990.


Parasitization Of Callinectes Rathbunae And Callinectes Sapidus By The Rhizocephalan Barnacle Loxothylacus Texanus In Alvarado Lagoon, Veracruz, Mexico, Fernando Alvarez, Adolfo Gracia, Rafael Robles, Jorge Calderon Jan 1999

Parasitization Of Callinectes Rathbunae And Callinectes Sapidus By The Rhizocephalan Barnacle Loxothylacus Texanus In Alvarado Lagoon, Veracruz, Mexico, Fernando Alvarez, Adolfo Gracia, Rafael Robles, Jorge Calderon

Gulf and Caribbean Research

Callinectes rathbunae and CalIinectes sapidus in Alvarado Lagoon, Mexico, were sampled monthly for one year to determine the extent of parasitization by the rhizocephalan cirripede Loxothylacus texanus. Prevalence levels. host sex ratio, carapace width-weight variation, and distribution of the number of parasites among hosts were analyzed. Loxothylacus texanus was present almost exclusively in C. rathbunae with a mean prevalence of 7.58%, while less than 1% of all C. sapidus were parasitized. Callinectes rathbunae constitutes a new host record for this parasite. A study of infection revealed significant variation in prevalence and host size throughout the study period. The sex …


A Survey Of The Reef-Related Medusa (Cnidaria) Community In The Western Caribbean Sea, E. Suarez-Morales, L. Segura-Puertas, R. Gasca Jan 1999

A Survey Of The Reef-Related Medusa (Cnidaria) Community In The Western Caribbean Sea, E. Suarez-Morales, L. Segura-Puertas, R. Gasca

Gulf and Caribbean Research

The species composition, distribution, and abundance of medusae collected during a 4-day plankton survey in a reef system of the Mexican Caribbean were studied. Highest mean medusae abundance was observed over the fore-reef zone and in daytime samples. Lowest abundances occurred in the reef lagoon and at dusk. Seventeen species were identified, with Liriope tetraphylla, Aglaura hemistoma, Cubaia aphrodite, and Sarsia prolifera being the most abundant. They belong to a group of medusae dominant along the world's second largest barrier reef. Cluster analysis revealed primary (fore-reef) and secondary (reef lagoon, channel) oceanic groups, showing the strong oceanic …


Variations In The Ventral Ciliature Of The Crustacean Symbiont Hyalophysa (Ciliophora, Apostomatida) From Mobile Bay And Dauphin Island, Alabama, Stephen C. Landers, Michael A. Zimlich, Tom Coate Jan 1999

Variations In The Ventral Ciliature Of The Crustacean Symbiont Hyalophysa (Ciliophora, Apostomatida) From Mobile Bay And Dauphin Island, Alabama, Stephen C. Landers, Michael A. Zimlich, Tom Coate

Gulf and Caribbean Research

Apostome ciliates are symbiotic organisms whose life cycles are complex and involve specific feeding, divisional, migratory, and phoretic stages. In this study we examined apostome trophonts (the diagnostic stage) from a variety of crustacean hosts in the Mobile Bay and Dauphin Island, Alabama, area. The hosts were grass shrimp (Palaemonetes pugio and P. paludosus), striped hermit crab (Clibanarius vittatus), blue crab (Callinectes sapidus), and pink shrimp (Farfantepenaeus (=Penaeus) duorarum). A number of similar but distinct morphotypes of apostomes were present, those corresponding to descriptions of species of Hyalophysa as well …


Gordon Pennington Gunter, 1909-1998, W. David Burke Jan 1999

Gordon Pennington Gunter, 1909-1998, W. David Burke

Gulf and Caribbean Research

Memorial of Gordon Gunter, former director of the Gulf Coast Research Laboratory and the first editor of Gulf Research Reports.


Atlas Of Fishes Of The St. Louis Bay Drainage In Southern Mississippi, Royal D. Suttkus, David A. White, Maurice F. Mettee Jan 1999

Atlas Of Fishes Of The St. Louis Bay Drainage In Southern Mississippi, Royal D. Suttkus, David A. White, Maurice F. Mettee

Gulf and Caribbean Research

This atlas presents a comprehensive report on fishes collected in the St. Louis Bay drainage between October 1950 and October 1989, prior to several recent years of accelerated commercial and residential development. A total of 261 samples taken at 126 sites from headwaters of major streams to the mouth of St. Louis Bay resulted in the collection of 75,625 specimens representing 124 species plus 2 hybrid sunfish combinations. Precise locality data are given for each collection site, with number of species and specimens taken at each site, followed by a total list of species taken at each site. A distribution …


An Annotated Checklist And Key To Hermit Crabs Of Tampa Bay, Florida, And Surrounding Waters, Karen M. Strasser, W. Wayne Price Jan 1999

An Annotated Checklist And Key To Hermit Crabs Of Tampa Bay, Florida, And Surrounding Waters, Karen M. Strasser, W. Wayne Price

Gulf and Caribbean Research

Fourteen species of hermit crabs, belonging to 5 genera, were identified from 35 stations in Tampa Bay and adjacent continental shelf waters. Ninety-two samples were taken from the intertidal zone to 15 m with a variety of gear including dip nets, trawls, dredges, and hand collections using SCUBA. Pagurus maclaughlinae, Pagurus longicarpus, and Pagurus pollicaris were distributed throughout the bay. These species were often sympatric, and were commonly found in seagrass beds, sandy substrates, and sand/mud substrates, respectively. Clibanarius vittatus, Pagurus gymnodactylus, and Pagurus stimpsoni inhabited the higher salinity waters of the bay entrance. Paguristes sp., …


Effects Of Diflubenzeron On The Ontogeny Of Phototaxis By Palaemonetes Pugio, J.E.H. Wilson, R.B. Forward Jr., J.D. Costlow Jan 1999

Effects Of Diflubenzeron On The Ontogeny Of Phototaxis By Palaemonetes Pugio, J.E.H. Wilson, R.B. Forward Jr., J.D. Costlow

Gulf and Caribbean Research

The phototaxis by larvae of the grass shrimp Palaemonetes pugio that hatched from embryos which were exposed to a single pulse concentration of diflubenzuron (DFB; Dimilin®) was quantified. Stage IV embryos (6-day-old) were exposed to 0.5 µg/L of DFB for 4 days followed by transfer into clean seawater for the rest of the incubation period. The photoresponses of light-adapted larvae from untreated embryos and embryos treated with 0.5 µg/L DFB were monitored from 1 day through 8 day post hatch for phototactic responses to 500 nm light. Larvae from untreated embryos exhibited strong positive phototaxis at high light intensities (3 …


The Planktonic Copepods Of Coastal Saline Ponds Of The Cayman Islands With Special Reference To The Occurrence Of Mesocyclops Ogunnus Onabamiro, An Apparently Introduced Afro-Asian Cyclopoid, Eduardo Suarez-Morales, Jerry A. Mclelland, Janet Reid Jan 1999

The Planktonic Copepods Of Coastal Saline Ponds Of The Cayman Islands With Special Reference To The Occurrence Of Mesocyclops Ogunnus Onabamiro, An Apparently Introduced Afro-Asian Cyclopoid, Eduardo Suarez-Morales, Jerry A. Mclelland, Janet Reid

Gulf and Caribbean Research

Taxonomic analysis of the copepod specimens collected from 29 Cayman Island ponds revealed the presence of ten species including the nearly ubiquitous cyclopoid Apocyclops panamensis. This species was widespread throughout the islands, being collected at 27 of the sampling sites. Another common calanoid, Mastigodiaptomus nesus, occurred at nine sites on Grand Cayman and one on Cayman Brac. A cyclopoid of Afro-Asian origin, Mesocyclops ogunnus, was collected at two nearly fresh water sites on Grand Cayman and was considered to be a recent introduction. Because of its known adaptability to fluctuating environmental conditions, it is likely that M. …