Life Sciences Commons^™

Cholangioma In A Wild-Caught Sheepshead Minnow (Cyprinodon Variegatus) From The Northern Gulf Of Mexico, Lee A. Courtney

Gulf and Caribbean Research

A single case of ac holangioma occurred in the liver of a wild-caught sheepshead minnow (Cyprinodon variegatus). This is the first biliary neoplasm and second case of a hepatic neoplasm reported from a wild-caught specimen of this species. The findings further demonstrate the susceptibility of the sheepshead minnow to neoplasm development and add support to its selection as a subject for field monitoring of carcinogenic exposure.

First Sperm Whale (Physeter Macrocephalus) Record In Mississippi, Jon C. Peterson, Wayne Hoggard

Gulf and Caribbean Research

A sperm whale (Physeter macrocephalus) stranded on the south shore of Horn Island, Mississippi, represents the first record of this species in the state. The specimen, a neonate female, was euthanized at the stranding site. Tissue samples, blood samples, and stomach contents were analyzed following gross necropsy.

Optimization Approach To The Treatment Of Open Boundary-Conditions, I. Shulman, James K. Lewis

Faculty Publications

A solution to an optimization problem is developed that deals with minimizing a measure of difference between the values of observed and predicted variables at an open ocean boundary. Minimization is based on the change of the flux of energy through the open boundary. It is shown that many of the longwave radiation conditions that are commonly used in ocean modeling can be derived using this optimization criteria. However, the minimization process is seen to produce a modification of these radiation conditions in that they are multiplied by a coefficient, which allows the conditions to adapt to a change in …

Pseudione Overstreeti, New Species (Isopoda: Epicaridea: Bopyridae), A Parasite Of Callichirus Islagrande (Decapoda: Anomura: Callianassidae) From The Gulf Of Mexico, Daniel L. Adkison, Richard W. Heard

Gulf and Caribbean Research

Pseudione overstreeti, new species, is a common bopyrid that infests the branchial chamber of the beach ghost shrimp, Callichirus islagrande, occurring along beaches of the Gulf of Mexico from Cape San Blas, Florida to Paraiso, Tabasco, Mexico. Like other members of the genus Pseudione that infest callianassid shrimps, the female of P. overstreeti is characterized by biramous terminal appendages which result from the combination of uniramous uropods with the closely associated lateral plates of pleomere 6. From the other members of the genus Pseudione occurring on callianassid hosts, P. overstreeti is distinguished by the distinctive development of the …

Observations On Extant Populations Of The Softshell Clam, Mya Arenaria Linné, 1758 (Bivalvia: Myidae), From Georgia (Usa) Estuarine Habitats, Erik Rasmussen, Richard W. Heard

Gulf and Caribbean Research

The softshell clam, Mya arenaria Linné, 1758, is reported from Georgia (USA) estuarine habitats based on studies conducted between 1969 and 1972. Observations on Georgia estuarine habitats where extant populations of softshell clams occurred are described. On several occasions, fresh shells with periostracum and tissue remnants were found in a brackish drainage system on Sapelo Island. These shells represent the first southern records of extant populations of softshell clams from such a specialized habitat type. Living specimens of M. arenaria from the benthos and specimens in the stomach contents of stingrays (Dasyatis sabina) were collected at four stations …

Trophic Structure Of Macrobenthic Communities In Northern Gulf Of Mexico Estuaries, Gary R. Gaston, Steven S. Brown, Chet F. Rakocinski, Richard W. Heard, J. Kevin Summers

Gulf and Caribbean Research

Trophic structure of estuarine benthic communities in the northern Gulf of Mexico was characterized according to the functional roles and geographic distributions of the macrobenthos. Macrobenthic organisms collected during two years of study were assigned to trophic groups to assess the relative utilization of detritus and other resources. Three groups of detritivores (surface-deposit feeders, subsurface-deposit feeders, and filter feeders) were numerically dominant among the benthos, each of which accounted for 25-30% of total abundance across regions. Carnivorous macrobenthos also comprised an appreciable portion (12%), while omnivores (<3%) and other groups (<4%) were poorly represented. Dominance by detritivores is consistent with current concepts regarding the role of macrobenthos in processing detritus of Gulf of Mexico estuaries.

A Study Of Factors Influencing The Hatch Rate Of Penaeus Vannamei Eggs. I. Effects Of Size, Shape And Volume Of The Spawning Tank, John T. Ogle

Gulf and Caribbean Research

The hatch rate of Penaeus vannamei eggs spawned by individual females in square and round tanks and in different volumes of seawater was determined. The mean hatch rates ranged from 17.3% to 64.9% and were not significantly different for volumes of 50, 100 and 200 L nor for square or round tanks of equal water volumes. Hatch rate was significantly affected by the size of the spawning tank.

Levinseniella Deblocki, New Species (Trematoda: Digenea: Microphallidae) From Salt Marshes Along The Eastern Gulf Of Mexico With Notes On Its Functional Morphology And Life History, Richard W. Heard, John M. Kinsella

Gulf and Caribbean Research

Levinseniella (Austromicrophallus) deblocki, n. sp., was collected during parasitologic studies of homeothermic vertebrates from salt marshes along the coast of the eastern Gulf of Mexico. Because L. deblocki lacks a femal epouch, it belongs to the subgenus Monarrhenos proposed by Deblock and Pearson (1970). However, since Deblock and Pearson did not explicitly designate a type species for Monarrhenos, it is not available and is a nomen nudum. The next available name, Austormicrophallus Szidat, 1964, a genus synonymized with Levinseniella Stiles and Hassall, 1901 by Deblock (1978), is reinstated as a subgenus to receive the species …

Gametogenic Cycle In The Non-Native Atlantic Surf Clam, Spisula Solidissima (Dillwyn, 1817), Cultured In The Coastal Waters Of Georgia, Christopher R. Spruck, Randal L. Walker, Mary L. Sweeney, Dorset H. Hurley

Gulf and Caribbean Research

This study describes the gametogenic cycle of the Atlantic surf clam, Spisula solidissima (Dillwyn, 1817), cultured from fall to spring in the coastal waters of Georgia, where it is non-native. Early active stages of gametogenic development began in November, with the majority (83%) of the animals in the early active stage by December. Gonadal indices increased to late active stages by March, with ripe individuals present in April. Spawning commenced in May and continued into June. Sex ratio (0.48 female to 1.00 male) was significantly unequal. Results of this study indicate that clams achieved sexual maturity and spawned when cultured …

A Study Of Factors Influencing The Hatch Rate Of Penaeus Vannamei Eggs. Ii. Presence Of A Spermatophore, John T. Ogle

Gulf and Caribbean Research

Eghty-three mated Penaeus vannamei females were sourced from a commercial sized maturation tank. The hatch rate was recorded for those shrimp based on the presence of a full spermatophore, a partial spermatophore or the loss of the spermatophore during sourcing and handling. The hatch rates were not significantly different among females for the three spermatophore conditions. The mean hatch rates were 48.8% for full spermatophores, 43.1% for partial spermatophores and 55.6% for lost spermatophores. The location of the sperm at fertilization and the precise mechanisms of fertilization are still unknown.

A Pugheaded Cobia (Rachycentron Canadum) From The Northcentral Gulf Of Mexico, James S. Franks

Gulf and Caribbean Research

A pugheaded cobia (Rachycentron canadum) captured in the northcentral Gulf of Mexico represents the first record of pugheadedness in cobia. The specimen, a 4-year-old gravid female, exhibited considerable distortion of the premaxillary and maxillary bones, with the length of the snout 46% shorter than that of a normal cobia of the same length. The anomaly had no apparent effect on feeding, since the stomach contained a substantial amount of food, and the fish was the same length expected of a normal 4-year-old cobia.

A Note On Bycatch Associated With Deepwater Trapping Of Chaceon In The Northcentral Gulf Of Mexico, Harriet Perry, Richard Waller, Christine Trigg, James Mcbee, Robert Erdman, Norman Blake

Gulf and Caribbean Research

Bycatch associated with deepwater trapping of Chaceon is reported for outer shelf and slope waters of the northcentral Gulf of Mexico. Bycatch was dominated by the isopod, Bathynomus giganteus. Other crustacean megafauna consisted of the majid crab, Rochinia crassa, and the portunid crabs, Benthochascon schmitti and Bathynectes longispina. Finfish bycatch included hagfish, Eptatretus springeri, deepwater shark, Centrophorus uyato and hake, Urophycis cirrata.

The Distribution And Abundance Of The Bay Anchovy, Anchoa Mitchilli, In A Southeast Texas Marsh Lake System, Scott A. Griffith, David L. Bechler

Gulf and Caribbean Research

A one-year distribution and abundance study on the bay anchovy, Anchoa mitchilli, was conducted in a southeast Texas marsh-lake system from March 1990 through February 1991. Day and night collections were conducted in backwaters, lake shores, and lake centers by seining and trawling. Bay anchovies were the second most abundant fish species collected, and exhibited seasonal, diet and habitat variations in abundance and distribution. Across the study area, seasonal abundance peaks occurred in May and August following migration into the marsh and seasonal recruitment. However, within each habitat type, peaks of abundance varied in time of occurrence. Within habitats, …

Estimates Of Harvest Potential And Distribution Of The Deep Sea Red Crab, Chaceon Quinquedens, In The North Central Gulf Of Mexico, Richard Waller, Harriet Perry, Christine Trigg, James Mcbee, Robert Erdman, Norman Blake

Gulf and Caribbean Research

Harvest potential, relative abundance, and geographic and bathymetric distribution are discussed for the red crab, Chaceon quinquedens, in the northcentral Gulf of Mexico. Harvest potential is expressed as the number of trapable crabs present on fishing grounds defined as depths ranging from 677 m to 1043 m between 87.5^o and 88.5^oW longitude. Using various estimates of the effective fishing area (EFA) of a trap, the number of trapable red crabs on the fishing grounds ranged from 3.7 x 10⁶ to 10.7 x 10⁶. Estimatesofcrabnumberssuggest there is a potential for commercial harvest in the …

Biochemical And Histological Changes During Ovarian Development Of Cobia, Rachycentron Canadum, From The Northern Gulf Of Mexico, Patricia M. Biesiot, Robert E. Caylor, James S. Franks

Faculty Publications

Female cobia, Rachycentron canadum, were sampled on their spawning grounds in the Northern Gulf of Mexico to study changes in proximate analysis (protein, lipid, carbohydrate, and ash) of the ovaries during gonadal maturation. Four major stages of oocyte development were studied: stage 1, previtellogenesis; stage 2, vitellogenesis; stage 3, final maturation; and stage 4, postovulation. Cobia are multiple spawning fish; therefore, ovaries engaged in a sequential round of oogenesis were distinguished as stages 1' and 2'. Protein was the major constituent of cobia ovaries and its contribution of cobia ovaries and its contribution remained fairly constant (49-55% fo the …

A New Species And Two Known Species Of Free-Living Marine Nematodes (Nematoda: Monoposthiidae) From Northwest Florida, U.S.A., Edwin J. Keppner

Gulf and Caribbean Research

Two known free-living marine nematodes, Monoposthioides mayri Wieser and Hopper, 1967 and Monoposthia hexalata Chitwood. 1936 are redescribed from sediments in St. Andrew Bay and Lake Powell, Bay County, Florida, U.S.A. One new species of free-living marine nematode, Monoposthia baxteri n. sp., is described from nonvegetated sediments in St. Andrew Bay, Bay County, Florida. M. baxteri n. sp. differs from the other members of the genus in the shape of the gubernaculum which is more similar to that of the species of Monoposthioides than that of Monoposthia.

Namalycastis Abiuma (Müller In Grube) 1871, An Aberrant Nereidid Polychaete Of A Georgia Salt Marsh Area And Its Faunal Associations, Erik Rasmussen

Gulf and Caribbean Research

The morphology of the aberrant nereidid Namalycastis abiuma, Namanereidinae is described on the basis of material collected 1971-72 and 1976 in the brackish water drainage ditch system of Sapelo Island, Georgia, USA. The systematics of the species is briefly reviewed. The habitat and ecological conditions under which the species lives in these brackish ditches are described.

At various times, N. abiuma lives out of water under the bark of trunks and branches of fallen trees. Decaying wood is ingested. It is suggested that future studies should concentrate on the reproductive biology of the widely spread, mainly tropical populations of what …

Historic Trends In The Secchi Disk Transparency Of Lake Pontchartrain, J.C. Francis, M.A. Poirrier, D.E. Barbe, V. Wijesundera, M.M. Mulino

Gulf and Caribbean Research

A major environmental concern about Lake Pontchartrain is an assumed long-term increase in turbidity based on Secchi disk transparency observations. Regression of the available data on Secchi disk transparency versus time (1953 through 1990) reveals a statistically significant decrease in transparency of about 40%. However, the data set is biased in that it does not adequately represent the seasonal effects of salinity and wind speed. Two analytical procedures were undertaken to determine the extent to which the apparent long-term decrease in transparency was dependent on the seasonal bias. One procedure involved seasonal adjustment of the data for the effects of …

Fatty Acid Pattern Differences Among Individuals Of Two Estuarine Fishes (Leiostomus Xanthurus And Mugil Cephalus), Julia S. Lytle, Thomas F. Lytle

Gulf and Caribbean Research

Ten individual fish of two estuarine species, spot (Leiostomus xanthurus) and striped mullet (Mugil cephalus), were analyzed for fatty acids. Fish of similar size were obtained from a single collection to minimize variability due to age, size, location and season. Analysis of variance (ANOVA) of each fatty acid provided statistically similar groups for each acid that existed among individual fish. Fatty acids in the striped mullet provided a greater number of statistically similar groups than those in spot, indicating greater variability among individual striped mullet, which probably reflected a greater diversity in the feeding regime for …

Long-Term Study Of Benthic Communities On The Continental Shelf Off Cameron, Louisiana: A Review Of Brine Effects And Hypoxia, Gary R. Gaston, Kenneth A. Edds

Gulf and Caribbean Research

A long-term data set compiled from our studies and a variety of investigations was analyzed to determine the effects of nine years of discharged brine (concentrated salt water) on benthic organisms surrounding a brine diffuser off Cameron, Louisiana (USA). These investigations began three months before brine discharge was initiated in 1981. A preliminary summary by Giammona and Darnell (1990) relied on just three years of discharge data and gave misleading reports of brine impacts.

Brine effects over the nine years of study were minimal, in part because the fine sediments of the study area were numerically dominated by opportunistic species. …

Behavioral Ecology Of Two Teal Species (Blue-Winged Teal, Anas Discors, And Green-Winged Teal, Anas Crecca) Overwintering In Marshes Of Coastal Louisiana, Usa, Gary R. Gaston, Jeanne C. Nasci

Gulf and Caribbean Research

Feeding and other dominant activities of Blue-winged Teal (BWT, Anas discors) and Green-winged Teal (GWT, Anas crecca) were compared from October 1987 to March 1988 in southwestern Louisiana, USA. Three observation towers were constructed near similar intermediate marsh habitats in areas where BWT and GWT concentrated for feeding. These observation towers allowed activities of the two species to be compared throughout the nonbreeding season. Although BWT and GWT often fed together, time spent in various activities differed. Feeding was the most frequent activity of both BWT(64.5%) and GWT (55.3%), but BWT spent more time feeding (P < 0.01) and alert (P < 0.05), but spent less (P < 0.01) time resting than GWT. Within each species there were differences in activity budgets among daily time blocks and among months, but few differences among the three habitats studied. Temperature and light intensity were correlated with resting (+), feeding (-), locomotion (-), and preening (+). Daily and monthly activity budgets of BWT and GWT were similar, as were ingested foods, suggesting that these two species used the study areas primarily for foraging, and left the areas for other activities. Predation and diminished resources during late winter may have affected activities of BWT and GWT as well.

The Scientific Publications Of Charles Eric Dawson (1948-1990), Stuart G. Poss, Elizabeth Heal

Gulf and Caribbean Research

By the time Charles Eric Dawson died on February 11, 1993, he had produced a total of 150 published papers. His contributions represent an important chapter in the ichthyological investigations of marine fishes. His work on fishes of the Americas and on the taxonomy of pipe fishes will long be remembered as two of his most significant and outstanding achievements. Although tribute to this Canadian-American Ichthyologist and longtime Senior Ichthyologist and curator of the ichthyological research collection at the Gulf Coast Research Laboratory is presented elsewhere (Overstreet and Poss, Copeia 1993(3):921-925), it is appropriate that the extensive bibliography of one …

Distributions Of Pigments And Primary Production In A Gulf-Stream Meander, Steven E. Lohrenz, John J. Cullen, David A. Phinney, Donald B. Olson, Charles S. Yentsch

Faculty Publications

An investigation was made of physical effects of Gulf Stream meandering on the vertical and horizontal distributions of photosynthetic pigments and primary production. Cruises were conducted in the vicinity of a meander east of 73-degrees-W and north of 37-degrees-N from September 21 to October 5 (leg 1) and October 12-21, 1988 (leg 2), on the R/V Cape Hatteras. Relationships of photosynthesis (normalized to chlorophyll) to irradiance (P-1) did not show large horizontal variation, and water column composite P-I curves from leg 1 and leg 2 were similar. Therefore a single P-I curve derived from pooled data was used to model …

Eleven New Species Of Free-Living Marine Nematodes, Edwin J. Keppner

Gulf and Caribbean Research

The genus Halalaimus is reviewed and divided into four groups based on characters of the male. Characters used to separate the groups of males include presence or absence of caudal algae and the presence or absence of a precloacal sensillum and/or pore. Ten new species are described from St. Andrew Bay, Bay County, Florida, and H. gerlachi n. sp. is proposed for H. gracilis sensu GerIach, 1967. New species from St. Andrew Bay are H. thalassinus, H. tarjani, H. bayensis, H. bulbocaudatus, H. variabilis, H. paracomatus, H. americanus, H. floridanus, H. brimi, …

Isopods Of The Genus Excorallana Stebbing, 1904 (Crustacea, Isopoda, Corallanidae) From The East Coast Of Mexico With A Supplemental Description Of E. Subtilis, Antonio Cantu-Diaz Barriga, Elva Escobar Briones

Gulf and Caribbean Research

Eight species of Excorallana, E. acuticauda, E. delaneyi, E. oculata, E. sexticornis, E. subtilis, E. tricornis tricornis, E. warmingii, and Excorallana sp. are recorded for the eastern coast of Mexico. The range of E. delaneyi is extended south in the Gulf of Mexico. Excorallana oculata and E. subtiIis are reported for the first time in the Gulf. Based on specimens from the east coast of Mexico, a supplemental description of E. subtilis is presented and its taxonomy to other closely related species discussed. A key is provided to the adult males of …

Ecological History, Catastrophism, And Human Impact On The Mississippi/Alabama Continental Shelf And Associated Waters: A Review, Rezneat M. Darnell

Gulf and Caribbean Research

The Mississippi/Alabama continental shelf and associated coastal waters together form a complex ecological system of interrelated parts. The biological system of the area has become established during the period of sea level rise following the last continental glacial maximum about 18,000 years ago. Contemporary biological populations of the inshore waters are subject to episodic catastrophic events caused by exceptional cold fronts, flooding, major storms, hypoxia, red tide outbreaks, and major droughts. Most of these events are not known to affect the shelf populations directly, but indirect effects through food chain disruptions are likely. Loop Current intrusions and entrainment of deep …

Feeding Biology, Distribution, And Ecology Of Two Species Of Benthic Polychaetes: Paraonis Fulgens And Paraonis Pygoenigmatica (Polychaeta: Paraonidae), Gary R. Gaston, Jerry A. Mclelland, Richard W. Heard

Gulf and Caribbean Research

Paraonis fulgens and Paraonis pygoenigmatica inhabit sandy littoral and sublittoral sediments of the northem Gulf of Mexico and U.S. East Coast, but seldom overlap in distribution. The purpose of this study was to compare the feeding ecology and distribution of these species. We analyzed distributions and gut contents of Gulf of Mexico specimens and found that P. fulgens inhabited substrates with slightly more silt and clay than those inhabited by P. pygoenigmatica. Although Paraonis fulgens ingested more diatoms than P. pygoenigmatica, this distinction likely resulted from habitat differences, not selective feeding. Previous studies suggested that P. fulgens fed …

Closed System Culture Of Penaeus Vannamei, John T. Ogle, Jeffrey M. Lotz

Gulf and Caribbean Research

Penaeus vannamei were cultured utilizing three different closed recirculating seawater systems. The first system used biological filtration for water treatment. The second system utilized both physical and chemical filtration, but no biological filtration. The third system used a combination of biological, physical, and chemical filtration. Shrimp growth was monitored for a 12-week period for each system. Shrimp from the biological filtration system had a growth rate of 0.82 g/wk and an overall survival rate of 45.6%. Shrimp from the closed system which used physical and chemical filtration had a growth rate of 0.99 g/wk and a survival rate of 29.2%. …

A Note On The Fine Structure Of Myoskeletal Junctions In Acartia Tonsa Dana (Copepoda, Calanoida), Harold D. Howse, William E. Hawkins, Harriet Perry

Gulf and Caribbean Research

The endoskeleton of the calanoid copepod, Calanus finmarchicus, and its muscle attachments were described by Lowe (1935). She reported that the endoskeleton in C. finmarchicus consists of two tendinous endosternites and chitinous exoskeletal ingrowths to which muscles are attached. Howse (1960) noted attachments of the main muscles of the thorax to the exoskeleton in Acartia tonsa.

Bouligand (1962) described the ultrastructure of muscle attachments to cuticle in three species of freshwater copepods of the genus Cyclops. Raymont et al. (1974) described the fine structure of muscle attachments to cuticle in C. finmarchicus.

Information of the …

Effects Of Salinity On Survival And Growth Of Postlarval Penaeus Vannamei, John T. Ogle, Kathy Beaugez, Jeffrey M. Lotz

Gulf and Caribbean Research

Eight and 22-day-old Penaeus vannamei postlarvae were exposed to several salinities for 24 hours and 120 hours by direct transfer from 32 ppt salinity to lower salinity waters. The challenge study included six experiments conducted on 8-day-old postlarvae (PL-8) and five experiments conducted on 22-day-old postlarvae (PL-22). Each experiment consisted of ten replicates of ten animals each. Shrimp were held in 1 L plastic containers with 500-ml of seawater. Lowered salinity resulted in lower survival for shrimp of both ages. Longer exposure time resulted in lower survival for shrimp of both ages. Younger shrimp exhibited lower survival than older shrimp. …