Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 15 of 15

Full-Text Articles in Life Sciences

High Cyanobacterial Abundance In Three Northeastern Gulf Of Mexico Estuaries, Michael C. Murrell, Jane M. Caffrey Jan 2005

High Cyanobacterial Abundance In Three Northeastern Gulf Of Mexico Estuaries, Michael C. Murrell, Jane M. Caffrey

Gulf and Caribbean Research

Aquatic phytoplankton comprise a wide variety of taxa spanning more than 2 orders of magnitude in size, yet studies of estuarine phytoplankton often overlook the picoplankton, particularly chroococcoid cyanobacteria (cf. Synechococcus). Three Gulf of Mexico estuaries (Apalachicola Bay, FL; Pensacola Bay, FL; Weeks Bay, AL) were sampled during summer and fall 2001 to quantify cyanobacterial abundance, to examine how cyanobacterial abundance varied with hydrographic and nutrient distributions, and to estimate the contribution of cyanobacteria to the bulk phytoplankton community. Cyanobacterial abundances in all 3 estuaries were high, averaging 0.59 ± 0.76 X 109 L–1 in Apalachicola Bay, …


Distribution Of Myodocopid Ostracods In Tampa Bay, Florida, And Association With Abiotic Variables, Stephen A. Grabe Jan 2005

Distribution Of Myodocopid Ostracods In Tampa Bay, Florida, And Association With Abiotic Variables, Stephen A. Grabe

Gulf and Caribbean Research

Myodocopid ostracods were identified from > 600 benthic samples collected from Tampa Bay, Florida, during 1995 to 2001, as part of an annual synoptic survey of the benthos. At least 24 taxa were present. Parasterope pollex was the most abundant (76%) and most frequently collected (48%) species; Rutiderma darbyi (28%) and Eusarsiella disparalis (16%) were the next most frequently collected species. Logistic regression and “center of abundance” calculations were used to identify habitat “preferences” for the most frequently occurring species. With the exception of P. pollex, these were more likely to occur in coarser sediments, in more saline waters, and at …


Parasites Of The American White Pelican, Robin M. Overstreet, Stephen S. Curran Jan 2005

Parasites Of The American White Pelican, Robin M. Overstreet, Stephen S. Curran

Gulf and Caribbean Research

Metazoan symbionts, including parasites, infecting the American white pelican (AWP) Pelecanus erythrorhynchos comprise a list of 75 species, 7 of which are new host records. Several new geographic records are also presented, but generally these have a low value because of the migratory nature of the bird. Evidence suggests that some parasites, mostly flies and other arthropods but also nematodes and digeneans, produce detrimental behavioral or pathologic changes in the AWP. Some of the arthropods transmit microbial agents to the pelican. Two digeneans that have the AWP as a definitive host harm and even kill their catfish intermediate host, especially …


Fishery And Biology Of Blackfin Tuna Thunnus Atlanticus Off Northeastern Brazil, Katia M.F. Freire, Rosangela Lessa, Jorge Eduardo Lins-Oliveira Jan 2005

Fishery And Biology Of Blackfin Tuna Thunnus Atlanticus Off Northeastern Brazil, Katia M.F. Freire, Rosangela Lessa, Jorge Eduardo Lins-Oliveira

Gulf and Caribbean Research

Blackfin tuna, Thunnus atlanticus, is the target species of a handline artisanal fishery off northeastern Brazil in September–January, but it is also caught by anglers and as by-catch in industrial fisheries. The population structure, morphometric relationships, mortality, reproduction, and fishery dynamics were studied during 2 fishing seasons (1996 and 1997). The maximum length and weight observed were 87 cm FL and 10 kg Wd, respectively. Males were larger and predominant (1.9:1). The length at 50% maturity was 49.8 cm FL for females and 52.1 cm FL for males. This species uses the area for reproduction, although a …


Selected Life-History Observations On The Cayman Gambusia, Gambusia Xanthosoma Greenfield, 1983 (Poeciliidae), Michael A. Abney, Richard W. Heard, Chet F. Rakocinski Jan 2005

Selected Life-History Observations On The Cayman Gambusia, Gambusia Xanthosoma Greenfield, 1983 (Poeciliidae), Michael A. Abney, Richard W. Heard, Chet F. Rakocinski

Gulf and Caribbean Research

The Cayman gambusia (Gambusia xanthosoma Greenfield, 1983) is an uncommon species within the G. punctata species group, endemic to North Sound, Grand Cayman Island, BWI. Since the original description (Greenfield 1983) only phylogenetic information has been published and little is known of its habitat, feeding ecology, or reproductive life history (Wildrick and Greenfield 1985, Rauchenberger 1988). Originally described from a brackish-water (30 psu) mosquito control ditch, the species also occurred throughout marine mangrove habitat and inland saline ponds adjacent to North Sound, Grand Cayman Island. Here we present information on the habitat, diet, reproduction, life history, and parasites of …


Long-Term Fish Assemblage Dynamics Of The Alvarado Lagoon Estuary, Veracruz, Mexico, Rafael Chavez-Lopez, Jonathan Franco-Lopez, Angel Moran-Silva, Martin T. O'Connell Jan 2005

Long-Term Fish Assemblage Dynamics Of The Alvarado Lagoon Estuary, Veracruz, Mexico, Rafael Chavez-Lopez, Jonathan Franco-Lopez, Angel Moran-Silva, Martin T. O'Connell

Gulf and Caribbean Research

The fish assemblages of Alvarado Lagoon Estuary (a complex of coastal lagoons in the state of Veracruz, Mexico) have been surveyed intermittently by different researchers over the last 40 years. Assessing longterm trends in fish assemblage composition for this ecosystem is problematic due to differences in sampling efforts among the survey periods (1966–1968, 1987–1988, 1989, 1989–1990, 1990–1991 and 2000–2001) and by the inherent ecological variability of estuaries. To overcome these data limitations and better understand fish assemblage change over time, we used robust, simulation-based analyses to compare collections from the different surveys. The 107 fish species collected from the Alvarado …


Ecology Of The Rock Shrimp Sicyonia Dorsalis Kingsley, 1878 (Crustacea: Sicyoniidae) In A Subtropical Region Of Brazil, Rogerio Caetano Da Costa, Adilson Fransozo, Maria Lucia Negreiros-Fransozo Jan 2005

Ecology Of The Rock Shrimp Sicyonia Dorsalis Kingsley, 1878 (Crustacea: Sicyoniidae) In A Subtropical Region Of Brazil, Rogerio Caetano Da Costa, Adilson Fransozo, Maria Lucia Negreiros-Fransozo

Gulf and Caribbean Research

The present study analyzes the abundance and distribution of the rock shrimp Sicyonia dorsalis, in relation to water temperature, salinity, depth, organic matter content, and sediment texture in Mar Virado (MV), Ubatuba (UBA) and Ubatumirim (UBM), 3 distinct bays along the northern coast of São Paulo State (23°S, 45°W), Brazil. Six transects were taken in each bay, 4 being parallel to the coastline and 2 next to the rocky shores. Monthly samples were taken over a 2-year period (1998 and 1999) with a shrimp fishing boat equipped with double-rig nets. A total of 2,498 specimens was obtained with 804 …


Argulus Yucatanus N. Sp. (Crustacea: Branchiura) Parasitic On Cichlasoma Urophthalmus From Yucatan, Mexico, William J. Poly Jan 2005

Argulus Yucatanus N. Sp. (Crustacea: Branchiura) Parasitic On Cichlasoma Urophthalmus From Yucatan, Mexico, William J. Poly

Gulf and Caribbean Research

A new species, Argulus yucatanus, is described based on 14 specimens from Cichlasoma urophthalmus collected in Celestun Lagoon, Yucatan, Mexico. Diagnostic characters include the number of and shape of sclerites in the suction cup support rods, shape of and position of respiratory areas, and modifications on the legs of males. In males, the coxae of the 2nd legs bear an angular lobe with 5–7 erect scales and 13–21 sensilla. The new species is compared to Argulus funduli Krøyer, 1863, A. chromidis Krøyer, 1863, A. cubensis Wilson, 1936, A. rhamdiae Wilson, 1936, and A. varians Bere, 1936.


Manatee Occurrence In The Northern Gulf Of Mexico, West Of Florida, D. Fertl, A.J. Schiro, G.T. Regan, C.A. Beck, N. Adimey, L. Price-May, A. Amos, G.A.J. Worthy, R. Crossland Jan 2005

Manatee Occurrence In The Northern Gulf Of Mexico, West Of Florida, D. Fertl, A.J. Schiro, G.T. Regan, C.A. Beck, N. Adimey, L. Price-May, A. Amos, G.A.J. Worthy, R. Crossland

Gulf and Caribbean Research

Reports of West Indian manatees (Trichechus manatus) in the US Gulf of Mexico west of Florida have increased during the last decade. We reviewed all available manatee sighting, capture, and carcass records (n = 377) from Alabama, Louisiana, Mississippi, and Texas since the early 1900s; only 40 of these were previously published. Manatees were reported most often in estuarine habitats, usually either near a freshwater source or natural or industrial warm-water springs/runoffs during winter months. The recent increase in manatee records may be due to a combination of increased public awareness and dispersal of manatees, most likely seasonal …


First Report Of The Mayan Cichlid, Cichlasoma Urophthalmus (Günther 1862) Collected In The Southern Littoral Zone Of Lake Okeechobee, Florida, Wilfredo A. Matamoros, Keith D. Chin, Bruce Sharfstein Jan 2005

First Report Of The Mayan Cichlid, Cichlasoma Urophthalmus (Günther 1862) Collected In The Southern Littoral Zone Of Lake Okeechobee, Florida, Wilfredo A. Matamoros, Keith D. Chin, Bruce Sharfstein

Gulf and Caribbean Research

Here we report the collection of five juvenile Mayan cichlids in Lake Okeechobee, a large, shallow subtropical lake (26°60'N, 80°50'W). These specimens were collected on 4 and 10 November 2003 in the southern littoral zone of Lake Okeechobee at a site off the southwest tip of Torry Island (26°42'N, 80°44'W). The lake stage of this densely vegetated area is highly variable. Nico (in press) reported a single collection of 16 juvenile Mayan cichlids in 2001 from a backwater area in the rim-canal along the NE portion of Lake Okeechobee; an area that is hydrologically isolated from the lake proper, except …


Ecology Of The Mayan Cichlid, Cichlasoma Urophthalmus Günther, In The Alvarado Lagoonal System, Veracruz, Mexico, Rafael Chavez-Lopez, Mark S. Peterson, Nancy J. Brown-Peterson, Ana Adalia Morales-Gomez, Jonathan Franco-Lopez Jan 2005

Ecology Of The Mayan Cichlid, Cichlasoma Urophthalmus Günther, In The Alvarado Lagoonal System, Veracruz, Mexico, Rafael Chavez-Lopez, Mark S. Peterson, Nancy J. Brown-Peterson, Ana Adalia Morales-Gomez, Jonathan Franco-Lopez

Gulf and Caribbean Research

The Mayan cichlid, Cichlasoma urophthalmus, has a wide distribution in southeastern Mexico where it inhabits rivers and coastal lagoons. In the Alvarado lagoonal system, Veracruz, it is distributed towards the north in Camaronera Lagoon. The Mayan cichlid shows an affinity for oligohaline to mesohaline sites with submerged vegetation, well-oxygenated, deep, and transparent water. The major abundance and biomass of this species was obtained during December to February. The diet of Mayan cichlids consists principally of plant detrital material and algae. Length-frequency distribution shows 2 size classes during both the dry and rainy seasons, corresponding to reproductive fish and young …


Recent Observations Of The Whale Shark (Rhincodon Typus) In The Northcentral Gulf Of Mexico, Eric R. Hoffmayer, James S. Franks, John P. Shelley Jan 2005

Recent Observations Of The Whale Shark (Rhincodon Typus) In The Northcentral Gulf Of Mexico, Eric R. Hoffmayer, James S. Franks, John P. Shelley

Gulf and Caribbean Research

The whale shark (Rhincodon typus Smith, 1828) is the world’s largest fish, reaching 15 meters (m) and 18 metric tons (Colman 1997) and is found in all tropical and warm temperate seas (Compagno 2001). The whale shark is listed as ‘vulnerable’ by the International Union for the Conservation of Nature and Natural Resources (IUCN 2004) and is included in Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES 2004). Little is known about whale sharks in the Gulf of Mexico (Gulf). Only reports on the occurrence of whale sharks off Texas …


Coastal Origin Of Common Snook, Centropomus Undecimalis, In Florida Bay, Heather M. Patterson, Ronald G. Taylor, Richard S. Mcbride Jan 2005

Coastal Origin Of Common Snook, Centropomus Undecimalis, In Florida Bay, Heather M. Patterson, Ronald G. Taylor, Richard S. Mcbride

Gulf and Caribbean Research

We used the elemental signatures of otoliths to investigate the coastal origin of common snook (Centropomus undecimalis) in Florida Bay, Florida and evaluate current management boundaries. We examined juvenile otoliths from Florida’s Atlantic and Gulf of Mexico (Gulf) populations and determined that there were significant differences in several elemental ratios (Mn/Ca, Cu/Ca, Sr/Ca, Ba/Ca). In addition, a discriminant function analysis (DFA) indicated a significant separation between the juveniles from each coast and otoliths were never misclassified by coast, indicating a distinct difference in their otolith chemistry. Using only juvenile otoliths to derive a calibration function, a separate DFA …


Seasonal And Spatial Patterns In Salinity, Nutrients, And Chlorophyll Α In The Alvarado Lagoonal System, Veracruz, Mexico, Angel Moran-Silva, Luis Antonio Martinez Franco, Rafael Chavez-Lopez, Jonathan Franco-Lopez, Carlos M. Bedia-Sanchez, Francisco Contreras Espinosa, Francisco Gutierrez Mendieta, Nancy J. Brown-Peterson, Mark S. Peterson Jan 2005

Seasonal And Spatial Patterns In Salinity, Nutrients, And Chlorophyll Α In The Alvarado Lagoonal System, Veracruz, Mexico, Angel Moran-Silva, Luis Antonio Martinez Franco, Rafael Chavez-Lopez, Jonathan Franco-Lopez, Carlos M. Bedia-Sanchez, Francisco Contreras Espinosa, Francisco Gutierrez Mendieta, Nancy J. Brown-Peterson, Mark S. Peterson

Gulf and Caribbean Research

Ten monthly collections, distributed among three seasons, were taken from July 2000 to June 2001 in the Alvarado lagoonal system, Veracruz, Mexico. Variables measured in situ included dissolved oxygen, salinity, and water temperature. Water samples were collected to determine concentrations of ammonium, nitrates, nitrites, orthophosphates, total phosphorus and chlorophyll α. Collections representing the rainy season were taken in September and October, those for the nortes season were taken in November, December, and January, and dry season collections were taken during February, March, May June, and July. There was seasonal and spatial variation in nutrient concentrations, and they were related to …


Trophic Relationships Of Demersal Fishes In The Shrimping Zone Off Alvarado Lagoon, Veracruz, Mexico, Edgar Pelaez-Rodriguez, Jonathan Franco-Lopez, Wilfredo A. Matamoros, Rafael Chavez-Lopez, Nancy J. Brown-Peterson Jan 2005

Trophic Relationships Of Demersal Fishes In The Shrimping Zone Off Alvarado Lagoon, Veracruz, Mexico, Edgar Pelaez-Rodriguez, Jonathan Franco-Lopez, Wilfredo A. Matamoros, Rafael Chavez-Lopez, Nancy J. Brown-Peterson

Gulf and Caribbean Research

The diet of demersal piscivorous fishes captured as bycatch of the commercial shrimping fleet off the Alvarado lagoonal system, Veracruz, Mexico, was studied. Nine collections distributed throughout the nortes (windy), wet, and dry seasons were made from November 1993 to January 1995. Sampling yielded a total of 646 fishes representing 10 families and 14 species, of which 44.9% had empty digestive tracts and were excluded from analysis. Trichiurus lepturus and Synodus foetens were the most abundant demersal predators in the collections. Differences in food consumption of the 7 most abundant predators were observed among the 3 seasons, with the greatest …