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Articles 1501 - 1530 of 1781

Full-Text Articles in Life Sciences

An Illustrated Record And Range Extension Of Caligus Chelifer (Copepoda, Siphonostomatoida) In The Gulf Of Mexico, E. Suarez-Morales, I. H. Kim, I. Lopez-Salgado Jan 1998

An Illustrated Record And Range Extension Of Caligus Chelifer (Copepoda, Siphonostomatoida) In The Gulf Of Mexico, E. Suarez-Morales, I. H. Kim, I. Lopez-Salgado

Gulf and Caribbean Research

A male specimen of the copepod Caligus chelifer Wilson, 1905, was collected during a plankton survey carried out during February 1994 off the Mexican coasts of the eastern Gulf of Mexico (Tamaulipas state). This is the first record of this species in Mexican waters and south of the 25ºN in the Northwestern Atlantic. Taxonomic illustrations of the specimen are provided.

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Genetic Variation In The Carolina Marsh Clam, Polymesoda Caroliniana, W.D. Grater, C.T. Hackney, D.J. Covington Jan 1998

Genetic Variation In The Carolina Marsh Clam, Polymesoda Caroliniana, W.D. Grater, C.T. Hackney, D.J. Covington

Gulf and Caribbean Research

Horizontal starch gel electrophoresis was used to detect genetic variation at eight enzyme loci and five general protein loci in 11 populations of Polymesoda caroliniana from the Gulf of Mexico and south Atlantic coast of the U.S. Little variability was found between four of these populations along a salinity gradient in the Cape Fear Estuary, NC, and a regional trend was not observed in other populations along a latitudinal gradient. Heterogeneity analyses and dendrograms, both based on allele frequencies, suggest populations from the Gulf coast of Florida are genetically different from both a northern Gulf population (Mississippi) and Atlantic populations. …

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Local Data Assimilation In Specification Of Open Boundary Conditions, Igor Shulman Dec 1997

Local Data Assimilation In Specification Of Open Boundary Conditions, Igor Shulman

Faculty Publications

A data assimilation approach to specify open boundary conditions is proposed. The boundary values are determined from the solution of the special optimization problem: minimization of the difference between the model and reference boundary values under the integral constraints on the open boundary. These constraints represent the energy, momentum, and mass fluxes through the open boundary. Reference values represent the a priori knowledge about the boundary values. They might be derived from observations, results of another model run, or from another approach to the specification of open boundary conditions. Optimized open boundary conditions are presented in detail for the barotropic …

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Finite Difference Of Adjoint Or Adjoint Of Finite Difference?, Ziv Sirkes, Eli Tziperman Dec 1997

Finite Difference Of Adjoint Or Adjoint Of Finite Difference?, Ziv Sirkes, Eli Tziperman

Faculty Publications

Adjoint models are used for atmospheric and oceanic sensitivity studies in order to efficiently evaluate the sensitivity of a cost function (e.g., the temperature or pressure at some target time t(f), averaged over some region of interest) with respect to the three-dimensional model initial conditions. The time-dependent sensitivity, that is the sensitivity to initial conditions as function of the initial time t(i), may be obtained directly and most efficiently from the adjoint model solution. There are two approaches to formulating an adjoint of a given model. In the first (''finite difference of adjoint''), one derives the continuous adjoint equations from …

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Time Series Measurements Of Chlorophyll Fluorescence In The Oceanic Bottom Boundary Layer With A Multisensor Fiber-Optic Fluorometer, Eurico J. Dsa, Steven E. Lohrenz, Vernon L. Asper, Roy A. Walters Aug 1997

Time Series Measurements Of Chlorophyll Fluorescence In The Oceanic Bottom Boundary Layer With A Multisensor Fiber-Optic Fluorometer, Eurico J. Dsa, Steven E. Lohrenz, Vernon L. Asper, Roy A. Walters

Faculty Publications

An in situ multisensor fiber-optic fluorometer (MFF) has been developed to acquire long-term chlorophyll fluorescence measurements in the oceanic bottom boundary layer to characterize the finescale pigment structure at vertical spatial scales comparable to physical measurements. The eight fluorescence sensors of the MFF are composed of dual optical fibers of varying lengths (1.5-8 m), with the fiber ends oriented at 30 degrees to each other and enclosed by a small light baffle. Strobe excitation blue light is passed through one of each pair of optical fibers and stimulated chlorophyll fluorescence is carried back to a photomultiplier. Two sets of four …

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The Probability Density Function Of Ocean Surface Slopes And Its Effects On Radar Backscatter, Y. Liu, Xh Yan, W.T. Liu, P.A. Hwang May 1997

The Probability Density Function Of Ocean Surface Slopes And Its Effects On Radar Backscatter, Y. Liu, Xh Yan, W.T. Liu, P.A. Hwang

Faculty Publications

Based on Longuet-Higgins's theory of the probability distribution of wave amplitude and wave period and on some observations, a new probability density function (PDF) of ocean surface slopes is derived. It is f(zeta(x), zeta(y)) = n/2 pi(n - 1)sigma(u) sigma(c) x [1 + zeta(x)(2)/(n - 1)sigma(n)(2) + zeta(y)(2)/(n - 1)sigma(c)(2)](-(n + 2)/2) + skewness, where zeta(x) and zeta(y) are the slope components in upwind and crosswind directions, respectively; sigma(u)(2) and sigma(c)(2) are the corresponding mean-square slopes. The peakedness of slopes is generated by nonlinear wave-wave interactions in the range of gravity waves. The skewness of slopes is generated by nonlinear …

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An Index To Assess The Sensitivity Of Gulf Of Mexico Species To Changes In Estuarine Salinity Regimes, John D. Christensen, Mark E. Monaco, Tony A. Lowery Jan 1997

An Index To Assess The Sensitivity Of Gulf Of Mexico Species To Changes In Estuarine Salinity Regimes, John D. Christensen, Mark E. Monaco, Tony A. Lowery

Gulf and Caribbean Research

An index of biological sensitivity to changes in freshwater inflow was developed for 44 species in 22 Gulf of Mexico estuaries for adult and juvenile life stages of fishes and macroinvertebrates. The BioSalinity Index (BSI) provides an innovative approach to quantify estuary-specific sensitivity of organisms to changes in estuarine salinity regimes based upon our knowledge of species salinity habitat preferences, the availability of this preferred habitat, and the relative abundance and distribution of species in time and space. We found that a significant difference exists between adult and juvenile life stage sensitivity, with juveniles exhibiting a lower sensitivity to salinity …

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Spatial And Temporal Changes In Subtidal Benthic Crustaceans Along A Coastal River-Estuarine Gradient In Mississippi, Mark S. Peterson Jan 1997

Spatial And Temporal Changes In Subtidal Benthic Crustaceans Along A Coastal River-Estuarine Gradient In Mississippi, Mark S. Peterson

Gulf and Caribbean Research

Benthic crustaceans were collected monthly between 24 August 1985 and 20 September 1986 from tidal freshwater (TFW), oligohaline (OH) and mesohaline (MH) sites in Old Fort Bayou, a black-water tidal river of the Biloxi Bay estuary, Mississippi. Salinity varied seasonally and spatially and was primarily related to variations in rainfall during this study. Reduced rainfall after October 1985 resulted in the upstream movement of saline water and a concommitant shift in benthic crustaceans upstream with this change in the physical-chemical environment. This shift is supported by a significant positive concordance of ranks between salinity and relative abundance of Gammarus sp. …

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Observations Of Sea Turtles And Other Marine Life At The Explosive Removal Of Offshore Oil And Gas Structures In The Gulf Of Mexico, Gregg R. Gitschlag, Bryan A. Herczeg, Theresa R. Barcak Jan 1997

Observations Of Sea Turtles And Other Marine Life At The Explosive Removal Of Offshore Oil And Gas Structures In The Gulf Of Mexico, Gregg R. Gitschlag, Bryan A. Herczeg, Theresa R. Barcak

Gulf and Caribbean Research

Observers monitored the explosive removal of oil and gas structures in the Gulf of Mexico to protect sea turtles and marine mammals from adverse impacts. More than 7,000 monitoring hours at 131 structure removals were conducted during 1993. Sixteen individual sea turtles were observed including 6 loggerheads, 1 Kemp's ridley, 1 green, and 8 unidentified sea turtles. Aerial surveys were approximately ten times more effective in observing sea turtles than day or night surface surveys.

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Zooplankton Variability And Copepod Species Assemblages From A Tropical Coastal Lagoon, J.N. Alvarez-Cadena, L. Segura-Puertas Jan 1997

Zooplankton Variability And Copepod Species Assemblages From A Tropical Coastal Lagoon, J.N. Alvarez-Cadena, L. Segura-Puertas

Gulf and Caribbean Research

Results of monthly zooplankton sampling, carried out from December 1990 to November 1991, are compared from three localities in the Mexican Caribbean. Two stations, Bojórquez, and Cuenca Norte, represent partially enclosed areas of the Nichupté Lagoon System in the northeastern region of the Yucatán Peninsula; a third station was located in adjacent neritic waters. At the neritic station, temperature was lower, salinity was higher, and variations in the two parameters smaller as compared to the two lagoon stations. Zooplankton abundance ranged from 3585.5 org./m3 at the neritic station to 18,742.7 org./m3 at Cuenca Norte. Considering all animals collected, …

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Butyltins In Crassostrea Virginica From Nine Reefs In Mississippi Sound, Thomas F. Lytle, Julia S. Lytle Jan 1997

Butyltins In Crassostrea Virginica From Nine Reefs In Mississippi Sound, Thomas F. Lytle, Julia S. Lytle

Gulf and Caribbean Research

Tributyltin (TBT), a very effective anti-foulant, has been banned from most marine paint uses since 1988 because of its reputed toxicity to nontarget organisms. Crassostrea virginica were collected from nine reefs in the Mississippi Sound in 1993 and analyzed for concentrations of butyltins: TBT, dibutyltin (DBT) and monobutyltin (MBT). TBT concentrations ranged from <2 to >20 ng(Sn)/g wet wt. Highest concentrations of butyltins were found at eastern Sound reefs near intense shipping and ship building activities with lowest concentrations found in the western Sound.

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Benthic-Pelagic Coupling In Northern Gulf Of Mexico Estuaries: Do Benthos Feed Directly On Phytoplankton?, Gary R. Gaston, Carol M. Cleveland, Steven S. Brown, Chet F. Rakocinski Jan 1997

Benthic-Pelagic Coupling In Northern Gulf Of Mexico Estuaries: Do Benthos Feed Directly On Phytoplankton?, Gary R. Gaston, Carol M. Cleveland, Steven S. Brown, Chet F. Rakocinski

Gulf and Caribbean Research

Few of the dominant benthic taxa of the northern Gulf of Mexico feed directly on phytoplankton. Rather, most of them feed on near-bottom seston and detritus. This is in contrast to models for Chesapeake Bay and San Francisco Bay. We found that detritivores represented over 80% of the macrobenthic organisms and over 90% of the biomass in Gulf of Mexico estuaries. The paucity of benthos that consumed phytoplankton led us to hypothesize that macrobenthos in Gulf of Mexico estuaries had less effect on plankton communities than was documented in U.S. east coast and west coast estuaries, where benthic communities consumed …

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Early Growth In Weight Of Kemp's Ridley Sea Turtles (Lepidochelys Kempii) In Captivity, Charles W. Caillouet Jr., Clark T. Fontaine, Theodore D. Williams, Sharon A. Manzella-Tirpak Jan 1997

Early Growth In Weight Of Kemp's Ridley Sea Turtles (Lepidochelys Kempii) In Captivity, Charles W. Caillouet Jr., Clark T. Fontaine, Theodore D. Williams, Sharon A. Manzella-Tirpak

Gulf and Caribbean Research

Growth in individual weight (w, kg) of Kemp’s ridley sea turtles (Lepidochelys kempii) in captivity was described for 15 year-classes (1978-1992) of turtles between ages (t) 0.17 to 1.22 yr, using In linear regression: Inw = lnc + dt1/2, where Inc is the intercept and d is the slope (growth rate index). There was significant (P < 0.001) heterogeneity in d among year-classes, with slowest growth (d = 3.798) exhibited by the 1983 year-class and fastest growth (d = 6.929) by the 1985 year-class, but there was no significant trend in d (P = 0.307) over year-classes. The variance of residuals from regression, s2reg, ranged from 0.2032 for the 1978 year-class to 0.0075 for the 1992 year-class, and showed a significant (P = 0.0001) logarithmic decrease over the year-classes. This decline in variation among individuals was probably due to a a …

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Identification, Distribution, And Aspects Of The Biology Of Ten Anthuridean Isopod Species From The Shallow Continental Shelf Of The U.S. Gulf And East Coast, Brian Kensley Jan 1997

Identification, Distribution, And Aspects Of The Biology Of Ten Anthuridean Isopod Species From The Shallow Continental Shelf Of The U.S. Gulf And East Coast, Brian Kensley

Gulf and Caribbean Research

With the aim of easing identification of continental shelf isopods, ten species of anthurideans, viz. Amakusanthura magnifica, Amakusanthura signata, Cyathura barbancki, Ptilanthura colpos, Ptilanthura tenuis, Hyssura bacescui, Kupellonura formosa, Neohyssura irpex, Xenanthura brevitelson, and Accalathura crenulata, are given brief diagnoses. A map showing the distribution of records, line figures illustrating diagnostic features, and a key to families, genera, and species are also provided.

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Distribution And Abundance Of Chaetognatha On The Yucatan Shelf During May, 1986., Silvia Mille-Pagaza, Rocio Reyes-Martinez, M. Elena Sanchez-Salazar Jan 1997

Distribution And Abundance Of Chaetognatha On The Yucatan Shelf During May, 1986., Silvia Mille-Pagaza, Rocio Reyes-Martinez, M. Elena Sanchez-Salazar

Gulf and Caribbean Research

An analysis of chaetognath species distribution and abundance from the Yucatan Shelf during May 1986 is presented. Zooplankton samples and associated hydrographic data were collected at 21 stations off the northern and northwestern coasts of the peninsula. Density data were classified and analyzed by calculating the Euclidian distance. In addition, the Importance Value of the species was obtained. Highest abundance (1000 to 5000 orgs./100m3) occurred in the northern and northwestern zones off the peninsula, while species richness was higher at oceanic stations farther offshore. The most abundant and frequent species were Sagitta enflata and S. bipunctata. The …

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Size And Weight Relationships For The Golden Crab, Chaceon Fenneri, And The Red Crab, Chaceon Quinquedens, From The Eastern Gulf Of Mexico, Christine Trigg, Harriet Perry Jan 1997

Size And Weight Relationships For The Golden Crab, Chaceon Fenneri, And The Red Crab, Chaceon Quinquedens, From The Eastern Gulf Of Mexico, Christine Trigg, Harriet Perry

Gulf and Caribbean Research

Carapace length, carapace width, and weight relationships are discussed for the golden crab, Chaceon fenneri, and the red crab, Chaceon quinquedens, from the eastern Gulf of Mexico. Males of both species were significantly larger than females in comparisons of means of all measured parameters. Relationships between carapace length and carapace width, carapace length and weight, and carapace width and weight were similar between Atlantic and Gulf of Mexico populations for both species.

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Stomatopod Crustaceans From The Carolinas And Georgia, Southeastern United States, Raymond B. Manning, Richard W. Heard Jan 1997

Stomatopod Crustaceans From The Carolinas And Georgia, Southeastern United States, Raymond B. Manning, Richard W. Heard

Gulf and Caribbean Research

Literature and specimen records are updated for stomatopod crustaceans known from the coasts of the Carolinas and Georgia. Gibbesia, new genus, is recognized for Squilla neglecta, and a new species, Neogonodactylus wennerae, is named for an offshore species of Neogonodactylus previously identified with the Caribbean shore species N. bredini. Fifteen species of stomatopods representing 12 genera are now known from the area: Bigelowina biminiensis (Bigelow), Cloridopsis dubia (Milne Edwards), Coronis scolopendra Latreille, Gibbesia neglecta (Gibbes), Heterosquilloides armata (Smith), Meiosquilla quadridens (Bigelow), Lysiosquilla scabricauda (Lamarck), Lysiosquillina glabriuscula (Lamarck), Nannosquilla carolinensis Manning, N. whitingi Camp & Manning, Neogonodactylus …

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A Study Of Factors Influencing The Hatch Rate Of Penaeus Vannamei Eggs. Iii. Presence Of The Female After Spawning, John T. Ogle, Kathleen A. Beaugez Jan 1997

A Study Of Factors Influencing The Hatch Rate Of Penaeus Vannamei Eggs. Iii. Presence Of The Female After Spawning, John T. Ogle, Kathleen A. Beaugez

Gulf and Caribbean Research

A comparison was made of the hatch rate (percent hatch) of Penaeus vannamei eggs. The study was comprised of 100 spawns from mated Penaeus vannamei females. In,one treatment, 50 female shrimp were removed from the isolation spawning tanks after spawning occurred but prior to hatching of eggs, producing 49.7% mean hatch rate. In the other treatment, 50 female shrimp were left in the tanks until after the eggs had hatched, producing an average hatch rate of 35.0%. A significant difference in the hatch rates of eggs was observed between spawns with and without presence of the female at time of …

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Distributional And Ecological Notes On The Halfbeaks Of Eastern Gulf Of Mexico, With A Provisional Key For Their Identification, S. Contreras-Balderas, M.L. Lozano-Vilano, M.E. Garcia Ramirez Jan 1997

Distributional And Ecological Notes On The Halfbeaks Of Eastern Gulf Of Mexico, With A Provisional Key For Their Identification, S. Contreras-Balderas, M.L. Lozano-Vilano, M.E. Garcia Ramirez

Gulf and Caribbean Research

Several fishes of the halfbeak genus Hyporhamphus occurring in the Mexican Gulf of Mexico and Caribbean Sea have been misidentified or confused in the literature. Most of it has centered around the taxonomic status of H. unifasciatus (including its synonym H. roberti), which is shown to comprise a complex of three species, H. unifasciatus, the recently described H. meeki, from the western Atlantic region, and an undescribed species from the eastern Pacific Ocean. Another eastern Mexico halfbeak is the freshwater form H. mexicanus. Using Banford and Collette (1993), we examined specimens from collections at UANL, UNAM, …

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Observations On Mass Mortalities Of The Sooty Eel, Bascanichthys Bascanium, And The Speckled Worm Eel, Myrophis Punctatus, Associated With A Fish Kill In The Mississippi Sound, James S. Franks, Ross P. Dodds Jan 1997

Observations On Mass Mortalities Of The Sooty Eel, Bascanichthys Bascanium, And The Speckled Worm Eel, Myrophis Punctatus, Associated With A Fish Kill In The Mississippi Sound, James S. Franks, Ross P. Dodds

Gulf and Caribbean Research

Mass mortalities of the sooty eel, Bascanichthys bascanium, and the speckled worm eel, Myrophis punctatus, were observed in association with a fish kill which occurred the morning of 18 June 1994 on the south shore of Deer Island, a nearshore barrier island located off Biloxi, Mississippi. B. bascanium and M. punctatus, as well as other fishes, were found dead and dying near the shore in reddish-brown water and along a lengthy stretch of fringing sandy beach. Both species of eels are infrequently reported from Mississippi waters but were the most abundant fishes recorded from the kill. A …

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Northern Record For The Zooxanthellate Scleractinian Coral Siderastrea Siderea (Ellis And Solander) From The Gulf Of Mexico, William W. Schroeder, Thomas S. Hopkins Jan 1997

Northern Record For The Zooxanthellate Scleractinian Coral Siderastrea Siderea (Ellis And Solander) From The Gulf Of Mexico, William W. Schroeder, Thomas S. Hopkins

Gulf and Caribbean Research

We report a northward range extension of the zooxanthellate scleractinian coral Siderastrea siderea (Ellis and Solander) in the Gulf of Mexico. Several small, living colonies of S. siderea have been obtained in dredge samples from a site located at 29º 55.5' N, 087º 28.4' W in the northeastern Gulf of Mexico. Prior to these collections the northernmost occurrence of S. siderea in the Gulf of Mexico was reported as 27º 54.5' N, 093º 35.8' W, on the East Flower Garden Bank, in the western Gulf of Mexico. In the eastern Gulf of Mexico, S. siderea is not reported occurring on …

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Morphometry Of Juvenile And Subadult Loligo Pealei And L. Plei From The Northern Gulf Of Mexico, Guillermo Sánchez, Harriet M. Perry, Christine B. Trigg, Michael Vecchione, Clyde Roper, Patricia M. Biesot Jul 1996

Morphometry Of Juvenile And Subadult Loligo Pealei And L. Plei From The Northern Gulf Of Mexico, Guillermo Sánchez, Harriet M. Perry, Christine B. Trigg, Michael Vecchione, Clyde Roper, Patricia M. Biesot

Faculty Publications

Two species of Loligo are abundant in northern Gulf waters: the long-finned squid, Loligo pealei. and the arrow squid, Loligo plei. Variability within species and similarities between the species often hamper accurate identification. The two species more closely resemble each other in areas of sympatry. and there is overlap in almost all of the diagnostic characters. Small specimens of Loligo are not easily identified. and there are few studies detailing their morphometry. Because of the taxonomic uncertainties associated with the identification of juveniles and subadults of L. pealei and L. plei, the species were differentiated by isoelectric …

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Gonadal Maturation In The Cobia, Rachycentron Canadum, From The Northcentral Gulf Of Mexico, Jeffrey M. Lotz, Robin M. Overstreet, James S. Franks Jan 1996

Gonadal Maturation In The Cobia, Rachycentron Canadum, From The Northcentral Gulf Of Mexico, Jeffrey M. Lotz, Robin M. Overstreet, James S. Franks

Gulf and Caribbean Research

Gonadal maturation of cobia, Rachycentron canadum, was evaluated by examining 508 specimens from its recreational fishery. Specimens were collected off southeast Louisiana to northwest Florida by hook-and-line during February through October 1987-1991. Fork lengths (FL) of these fish ranged from 580-1,530 mm, with corresponding weights of 2.0-43.5 kg. The female:male ratio was 1:0.37. Using a combination of oocyte size frequency and histological assessment of many of the fish, we determined that females were ripe from May through September, with atretic oocytes occurring in some fish from July through October. Degenerating hydrated oocytes in July and October and the presence …

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Food Of Cobia, Rachycentron Canadum, From The Northcentral Gulf Of Mexico, Gabriele H. Meyer, James S. Franks Jan 1996

Food Of Cobia, Rachycentron Canadum, From The Northcentral Gulf Of Mexico, Gabriele H. Meyer, James S. Franks

Gulf and Caribbean Research

The stomach contents of 403 cobia, Rachycentron canadum, caught in the northcentral Gulf of Mexico recreational fishery from April through October of 1987-1990 were examined. Cobia ranged from 373-1,530 mm in fork length. Of the 403 stomachs, 287 (71.2%) contained at least one identifiable prey taxon. Crustaceans, consisting primarily of portunid crabs, were the predominant food. Crustaceans occurred in 79.1% of the stomachs and comprised 77.6% of the total number of identifiable prey. The second most important prey category was fish which was dominated by hardhead catfish, Arius felis, and eels. Fish occurred in 58.5% of the stomachs …

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Cryopreservation Of Sperm Of Spotted Seatrout (Cynoscion Nebulosus), William R. Wayman, R. Glenn Thomas, Terrence R. Tiersch Jan 1996

Cryopreservation Of Sperm Of Spotted Seatrout (Cynoscion Nebulosus), William R. Wayman, R. Glenn Thomas, Terrence R. Tiersch

Gulf and Caribbean Research

Cryopreservation of fish sperm has applications in preserving genetic resources from stocks of endangered fishes, replenishing fisheries, reducing the number of males needed in hatchery situations, and allowing repeated spawning of specific males. As part of a larger study on artificial breeding of sciaenid fishes, we developed procedures for collection, handling, refrigerated storage, and cryopreservation of spotted seatrout sperm. Hanks' balanced salt solution (HBSS) was used as an extender for collection and storage of sperm. Sperm motility in relation to graded concentrations of HBSS was used to determine the osmolality at which sperm were activated. Based on these findings, HBSS …

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Distribution Of Loxothylacus Texanus (Cirripedia: Rhizocephala) Parasitizing Crabs Of The Genus Callinectes In The Southwestern Gulf Of Mexico, Fernando Alvarez, Jorge Calderon Jan 1996

Distribution Of Loxothylacus Texanus (Cirripedia: Rhizocephala) Parasitizing Crabs Of The Genus Callinectes In The Southwestern Gulf Of Mexico, Fernando Alvarez, Jorge Calderon

Gulf and Caribbean Research

A preliminary study on the interaction between the parasitic barnacle Loxothylacus texanus and two of its host species, the blue crab Callinectes sapidus and the dark blue crab C. rathbunae, in the Gulf of Mexico is presented. Data were obtained from 923 crabs, 162 C. sapidus and 761 C. rathbunae, deposited in the Colección de Crustáceos, Instituto de Biologia, Universidad Nacional Autónoma de México (UNAM), that were collected in 14 coastal lagoons and sites along the Mexican coast of the Gulf of Mexico. The distribution of L. texanus parasitizing each one of the host species, mean host size …

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Reproductive Strategies In A Population Of Gobiosoma Bosci (Osteichthyes: Gobiidae) With Slow And Fast Maturing Individuals, Candace H. Conn, David L. Bechler Jan 1996

Reproductive Strategies In A Population Of Gobiosoma Bosci (Osteichthyes: Gobiidae) With Slow And Fast Maturing Individuals, Candace H. Conn, David L. Bechler

Gulf and Caribbean Research

The reproductive biology of Gobiosoma bosci collected from November 1986 to October 1987 in the McFaddin Wildlife Refuge in southeast Texas was studied by using morphometric data. Males achieved greater weights per unit length than females, and longevity was about 12 to 13 months. GSI values and mean monthly ovum diameters indicated that the breeding season ran from April to September, with a major activity peak in May and a minor peak in September. Significant differences in male and female standard lengths (SL), ovum diameter, and egg number existed for sexually mature specimens between the first and second peaks of …

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Seasonal Migration In The Southern Hogchoker, Trinectes Maculatus Fasciatus (Achiridae), Tanya L. Peterson Jan 1996

Seasonal Migration In The Southern Hogchoker, Trinectes Maculatus Fasciatus (Achiridae), Tanya L. Peterson

Gulf and Caribbean Research

Life history patterns often respond to local environmental conditions. The seasonal migration pattern of the northern hogchoker has been described, but the southern subspecies rarely has been studied. To document the migratory movements and the habitat characteristics of the southern hogchoker, long-term survey data and specimens collected during 1993 were examined. Moderate depth (5.8-6.4 m), low water clarity (0-1.2 m), moderate oxygen concentration (4-9 ppm), and sand-mud substrata generally defined hogchoker habitats. Hogchoker habitats only showed seasonal shifts in temperature and salinity characteristics. Hogchokers were only collected in low salinity (0-2 ppt) waters during the winter, but exhibited three abundance …

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Observations On An Isolated Population Of Sagitta Hispida Conant (Chaetognatha) In A Tropical Lagoon System Of Northeast Yucatan (Mexico), Jose N. Alvarez-Cadena, Eduardo Suarez-Morales, Jerry A. Mclelland Jan 1996

Observations On An Isolated Population Of Sagitta Hispida Conant (Chaetognatha) In A Tropical Lagoon System Of Northeast Yucatan (Mexico), Jose N. Alvarez-Cadena, Eduardo Suarez-Morales, Jerry A. Mclelland

Gulf and Caribbean Research

Monthly zooplankton collections were carried out from January to December 1991 at two sampling sites, Cuenca Norte and Bojórquez lagoon, in the Nichupté lagoon system, a partially enclosed network of interconnected waterways located in the northeastern region of the Yucatan Peninsula (Mexico) adjacent to the Caribbean Sea. Only one species of Chaetognatha, Sagitta hispida Conant, was present and was more abundant at Cuenca Norte (total density 450.6 organisms/m3) than at Bojórquez (138.6 organisms/m3). The latter site is smaller, more physically isolated, and more environmentally stressed than the former. From monthly gonadal and length-frequency analyses of 1390 specimens, it was found …

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Aricidea (Allia) Bryani, A New Species Of Polychaete (Polychaeta: Paraonidae) From The Northern Gulf Of Mexico, Gary R. Gaston, Jerry A. Mclelland Jan 1996

Aricidea (Allia) Bryani, A New Species Of Polychaete (Polychaeta: Paraonidae) From The Northern Gulf Of Mexico, Gary R. Gaston, Jerry A. Mclelland

Gulf and Caribbean Research

Aricidea bryani, a new species of polychaete (Polychaeta: Paraonidae) belonging to the subgenus Allia Strelzov 1973, is described from shallow subtidal sediments along the northern shore of Mississippi Sound, an estuary of the northern Gulf of Mexico. The new species is distinguished from other members of the subgenus by the presence of tuberculate neuropodial lobes in the anterior 15-20 setigers, a cirriform median antenna that extends posteriorly to setiger three, and by modified neuropodial setae that are abruptly tapered at mid-length, but lack terminal aristae.

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