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Floodplain habitat use and movements of two centrarchids within pool B of the Kissimmee River, Florida
Title
Floodplain habitat use and movements of two centrarchids within pool B of the Kissimmee River, Florida.
Creator
Giles, Matthew Justin, Florida Atlantic University, Courtenay, Walter R. Jr., Wilzbach, Margaret A.
Abstract/Description
Floodplains are important elements of river-floodplain systems. Numerous riverine fishes utilize floodplain habitats for reproduction, feeding, and protection. Largemouth bass and bluegill sunfish were tracked using radiotelemetry, and environmental parameters were measured at fish locations. Bass and bluegill used habitats with the same physical and chemical characteristics. Floodplain habitats were utilized frequently, as much as main river channel habitats. Fishes used habitats dominated...
Show moreFloodplains are important elements of river-floodplain systems. Numerous riverine fishes utilize floodplain habitats for reproduction, feeding, and protection. Largemouth bass and bluegill sunfish were tracked using radiotelemetry, and environmental parameters were measured at fish locations. Bass and bluegill used habitats with the same physical and chemical characteristics. Floodplain habitats were utilized frequently, as much as main river channel habitats. Fishes used habitats dominated by vegetation, with sand substrates, and that were more stable with regard to environmental conditions. Largemouth bass were more mobile than bluegill sunfish. Fish movements may have been in response to unfavorable environmental conditions, as more mobile fishes were associated with higher water temperatures and lower concentrations of dissolved oxygen.
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Date Issued
1999
PURL
http://purl.flvc.org/fau/fd/FADT15728
Subject Headings
Floodplain ecology--Florida--Kissimmee River Watershed, Largemouth bass--Florida--Kissimmee River Watershed, Centrarchidae--Florida--Kissimmee River Watershed
Format
Document (PDF)
Fishes of the Kissimmee River floodplain, prior to proposed restoration
Title
Fishes of the Kissimmee River floodplain, prior to proposed restoration.
Creator
Overdorf, Tobin Rogers., Florida Atlantic University, Courtenay, Walter R. Jr.
Abstract/Description
The density and diversity of fishes of the Kissimmee River Floodplain have been affected by channelization of the Kissimmee River. Reduced hydrology, human encroachment, and overall loss of habitat appear to have reduced the level of fish diversity and density within the floodplain of the Kissimmee River. This landmark study collected vegetative habitat and fish population density and diversity data within the altered floodplain for baseline information prior to initiation of river...
Show moreThe density and diversity of fishes of the Kissimmee River Floodplain have been affected by channelization of the Kissimmee River. Reduced hydrology, human encroachment, and overall loss of habitat appear to have reduced the level of fish diversity and density within the floodplain of the Kissimmee River. This landmark study collected vegetative habitat and fish population density and diversity data within the altered floodplain for baseline information prior to initiation of river restoration activities in the form of dechannelization. Secondary studies included poecillid fecundity data as well as a localized rotenone study within the previously restored am of Pool B. Overall results of the study indicate that post restoration floodplain fish collection studies should reveal increased fish density and diversity within the expanded and restored floodplain habitat.
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Date Issued
1999
PURL
http://purl.flvc.org/fcla/dt/15736
Subject Headings
Fishes--Florida--Kissimmee River Watershed, Restoration ecology--Florida--Kissimmee River Watershed
Format
Document (PDF)
Evaluation of fish populations and relative abundance within Pools A, B and C of the Kissimmee River: Possible responses to the Pool B demonstration project
Title
Evaluation of fish populations and relative abundance within Pools A, B and C of the Kissimmee River: Possible responses to the Pool B demonstration project.
Creator
Miller, Daniel E., Florida Atlantic University, Courtenay, Walter R. Jr.
Abstract/Description
Channelization of the Kissimmee River from 1962 to 1971 altered the natural hydrology of the river/floodplain system. Results of construction of the C-38 canal included loss of continuous flow of water and loss of floodplain habitat which adversely impacted the fish community. In 1984 the South Florida Water Management District (SFWMD) constructed the Pool B demonstration project to evaluate the feasibility of a planned restoration project. To evaluate success of the demonstration project in...
Show moreChannelization of the Kissimmee River from 1962 to 1971 altered the natural hydrology of the river/floodplain system. Results of construction of the C-38 canal included loss of continuous flow of water and loss of floodplain habitat which adversely impacted the fish community. In 1984 the South Florida Water Management District (SFWMD) constructed the Pool B demonstration project to evaluate the feasibility of a planned restoration project. To evaluate success of the demonstration project in enhancing the Pool B fish fauna, a hoop net sampling program was conducted in 1996. The data suggest that black crappie (Pomoxis nigromaculatus) and other sport species in Pool B are benefiting from habitat enhancements resulting from the demonstration project. Additional analysis distinguishes black crappie as the only centrarchid sampled that maintains activity during nocturnal hours. Bluegill (Lepomis macrochirus) were most active during May sampling when water temperatures were optimal for spawning.
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Date Issued
1997
PURL
http://purl.flvc.org/fcla/dt/15456
Subject Headings
Fish habitat improvement--Florida--Kissimmee River, Fishes--Conservation--Florida--Kissimmee River, Fish populations--Florida--Kissimmee River--Measurement
Format
Document (PDF)
Separation of stocks of king mackerel Scomberomorus cavalla (Cuvier)
Title
Separation of stocks of king mackerel Scomberomorus cavalla (Cuvier).
Creator
Brandt, Andrea B., Florida Atlantic University, Courtenay, Walter R. Jr.
Abstract/Description
Meristic and morphometric characteristics as well as isoelectric focusing and two-dimensional electrophoretic protein banding patterns of Scomberomorus cavalla were investigated in an attempt to find a technique to adequately identify Atlantic and Gulf of Mexico migratory groups, respectively, in the southeast Florida mixing zone. Data were collected from king mackerel from three locations: Riviera Beach, Palm Beach County; St. Petersburg, Pinellas County; and Panama City, Bay County; Florida...
Show moreMeristic and morphometric characteristics as well as isoelectric focusing and two-dimensional electrophoretic protein banding patterns of Scomberomorus cavalla were investigated in an attempt to find a technique to adequately identify Atlantic and Gulf of Mexico migratory groups, respectively, in the southeast Florida mixing zone. Data were collected from king mackerel from three locations: Riviera Beach, Palm Beach County; St. Petersburg, Pinellas County; and Panama City, Bay County; Florida. Morphometric and electrophoretic differences in samples from St. Petersburg, may indicate that the fish collected in this region constitute a separate stock. Nevertheless none of these techniques was conclusive enough to be adequate in separating these fish stocks for management purposes.
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Date Issued
1998
PURL
http://purl.flvc.org/fcla/dt/15547
Subject Headings
King mackerel--Florida
Format
Document (PDF)
STUDY OF THE MORPHOLOGY AND ECOLOGICAL IMPACT OF TILAPIA AUREA (PISCES; CICHLIDAE) IN FLORIDA
Title
A STUDY OF THE MORPHOLOGY AND ECOLOGICAL IMPACT OF TILAPIA AUREA (PISCES; CICHLIDAE) IN FLORIDA.
Creator
BLAKESLEY, HOWARD LYMAN., Florida Atlantic University, Courtenay, Walter R. Jr.
Abstract/Description
A description of Tilapia aurea based on specimens from Florida is presented with an updated synonomy. The Florida specimens are compared with descriptions of specimens from Israel. It is concluded that Florida specimens have the same range in morphological variability as specimens from Isreal. The experimental work completed here indicates that Tilapia aurea does not adversely affect native fish populations. It is speculated that Tilapia aurea may have stabilized the experimental fish...
Show moreA description of Tilapia aurea based on specimens from Florida is presented with an updated synonomy. The Florida specimens are compared with descriptions of specimens from Israel. It is concluded that Florida specimens have the same range in morphological variability as specimens from Isreal. The experimental work completed here indicates that Tilapia aurea does not adversely affect native fish populations. It is speculated that Tilapia aurea may have stabilized the experimental fish populations by a "polyculture effect."
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Date Issued
1975
PURL
http://purl.flvc.org/fcla/dt/13704
Subject Headings
Tilapia--Florida, Fish populations--Florida
Format
Document (PDF)
Fish community structure and organization in neotropical clear and blackwater streams in Guyana
Title
Fish community structure and organization in neotropical clear and blackwater streams in Guyana.
Creator
Bergquist, Teresa Cecilia., Florida Atlantic University, Bourne, Godfrey R., Courtenay, Walter R. Jr.
Abstract/Description
Small clear and blackwater streams of the neotropics are economically important because they may be nursery grounds for important food and aquarium fishes. At present, these ecosystems are being negatively impacted by current logging, and gold and diamond mining practices. Thus, the role of biotic and abiotic factors in fish community structure was examined in three unimpacted streams in Guyana, South America. These streams had relatively low fish species diversity, but complex feeding guild...
Show moreSmall clear and blackwater streams of the neotropics are economically important because they may be nursery grounds for important food and aquarium fishes. At present, these ecosystems are being negatively impacted by current logging, and gold and diamond mining practices. Thus, the role of biotic and abiotic factors in fish community structure was examined in three unimpacted streams in Guyana, South America. These streams had relatively low fish species diversity, but complex feeding guild structure. No significant correlations between abiotic factors and fish species diversity and feeding guild diversity were determined due to small sample size. However, principal component analysis suggested an association between pH and species diversity, and conductivity and guild diversity. Biotic factors, such as competition and predation may be the primary determinant of fish community structure and organization in neotropical blackwater streams.
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Date Issued
1994
PURL
http://purl.flvc.org/fcla/dt/15023
Subject Headings
Fishes--Guyana, Fishes--Tropics, Freshwater fishes--Guyana, Species diversity--Guyana
Format
Document (PDF)
Growth of Tilapia mariae (Boulenger) fry in different salinities
Title
Growth of Tilapia mariae (Boulenger) fry in different salinities.
Creator
Garcia, Eileen Leonor, Florida Atlantic University, Adams, Ralph M., Courtenay, Walter R. Jr.
Abstract/Description
Gradual salinity acclimatization and growth studies were performed on fry of the spotted tilapia, Tilapia mariae. First, fry were successfully brought to a salinity of 40%. in 8 weeks by gradual weekly increments of 5 %.. Second, fry were exposed separately for nine weeks to salinities of 0, 5, 10, 20, 25, and 30 %.. Fish grew best at 5 and 10 %. (p
Show moreGradual salinity acclimatization and growth studies were performed on fry of the spotted tilapia, Tilapia mariae. First, fry were successfully brought to a salinity of 40%. in 8 weeks by gradual weekly increments of 5 %.. Second, fry were exposed separately for nine weeks to salinities of 0, 5, 10, 20, 25, and 30 %.. Fish grew best at 5 and 10 %. (p < 0.05) and least at 30 %.. At nine weeks, fish at 0, 5, 10, 20, 25, and 30%. appeared to be osmoregulating, as indicated by osmolarities of their inner body fluids. These results suggest that Tilapia mariae may become a competitive threat to fishes in native estuarine environments in southern Florida.
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Date Issued
1990
PURL
http://purl.flvc.org/fcla/dt/14640
Subject Headings
Tilapia--Effect of salt on
Format
Document (PDF)
Artificial reef morphology: Relationship to fish recruitment and community structure
Title
Artificial reef morphology: Relationship to fish recruitment and community structure.
Creator
Lea, Barbara Chudzik, Florida Atlantic University, Courtenay, Walter R. Jr., Bourne, Godfrey R., Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
Rock and coral reef fishes are known to select their habitat, and selection oftentimes involves the settlement of pelagic larval stages. Thus, I examined the short-term temporal relationship between artificial reef morphology and the composition of warm-water reef fish assemblages 30 m offshore of the Town of Palm Beach, Florida. Correlations were found between reef height and total fish abundance and species richness. Reef height was also correlated with log transformed numbers of juveniles....
Show moreRock and coral reef fishes are known to select their habitat, and selection oftentimes involves the settlement of pelagic larval stages. Thus, I examined the short-term temporal relationship between artificial reef morphology and the composition of warm-water reef fish assemblages 30 m offshore of the Town of Palm Beach, Florida. Correlations were found between reef height and total fish abundance and species richness. Reef height was also correlated with log transformed numbers of juveniles. Horizontal opening size showed an inverse correlation with species richness and a weak inverse trend with juvenile abundance. Furthermore, vertical openings were directly proportional to juvenile and total fish abundance, and to species richness. Piscivore abundance was weakly influenced by presence and dimensions of vertical crevices. Thus, artificial reefs with many varied-sized vertical crevices are most desirable for attracting juvenile warm-water reef fishes.
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Date Issued
1994
PURL
http://purl.flvc.org/fcla/dt/15063
Subject Headings
Artificial reefs, Coral reef fishes--Morphology
Format
Document (PDF)
LARVAL DEVELOPMENT OF THE SNOOK, CENTROPOMUS UNDECIMALIS (PISCES: CENTROPOMIDAE), REARED IN THE LABORATORY
Title
LARVAL DEVELOPMENT OF THE SNOOK, CENTROPOMUS UNDECIMALIS (PISCES: CENTROPOMIDAE), REARED IN THE LABORATORY.
Creator
LAU, STEPHEN R., Florida Atlantic University, Courtenay, Walter R. Jr., Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
Advanced embryos, larval and early juvenile snook, Centropomus undecimalis, are described from laboratory reared specimens. This description includes details of advanced embryos, changes in body shape, pigmentation, and osteological development. Eggs ranged from 0.68 to 0.73 mm in diameter with a single oil globule. Larvae were between 1.4 and 1.5 mm standard length at hatching. The yolk sac was absorbed by 2.2 mm and adult pigmentation began to appear on the head and fins by 7.0 mm....
Show moreAdvanced embryos, larval and early juvenile snook, Centropomus undecimalis, are described from laboratory reared specimens. This description includes details of advanced embryos, changes in body shape, pigmentation, and osteological development. Eggs ranged from 0.68 to 0.73 mm in diameter with a single oil globule. Larvae were between 1.4 and 1.5 mm standard length at hatching. The yolk sac was absorbed by 2.2 mm and adult pigmentation began to appear on the head and fins by 7.0 mm. Ossification had commenced by 5.5 mm and all bones, except the ethmoid and preyomer, had at least begun to ossify by 21.9 mm. Illustrations of snook eggs and larvae, including details of the caudal skeleton, are presented to show changes that occurred during development.
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Date Issued
1977
PURL
http://purl.flvc.org/fcla/dt/13894
Subject Headings
Centropomidae
Format
Document (PDF)
EASTERN PACIFIC FISHES OF THE GENUS HAEMULON (POMADASYIDAE)
Title
EASTERN PACIFIC FISHES OF THE GENUS HAEMULON (POMADASYIDAE).
Creator
HONG, SUSAN LEE, Florida Atlantic University, Courtenay, Walter R. Jr., Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
Five eastern Pacific species of the genus Haemulon Cuvier are described, their color pattern and dentition illustrated, and a key presented for their identification. Lythrulon Jordan and Swain and Orthostoechus Gill are synonymized with Haemulon. Haemulon scudderi Gill, Haemulon sexfasciatum Gill, Haemulon flavigattatum Gill, and Haemulon maculicauda (Gill) are found exclusively in the Pacific while Haemulon steindachneri (Jordan and Gilbert) is found both in the Atlantic and the Pacific.
Date Issued
1974
PURL
http://purl.flvc.org/fcla/dt/13676
Subject Headings
Grunts (Fishes)
Format
Document (PDF)
HABITAT PREFERENCES AND ASSOCIATIONS OF A UNISEXUAL-BISEXUAL COMPLEX OF POECILIA (PISCES: POECILIIDAE) FROM NORTHEASTERN MEXICO
Title
HABITAT PREFERENCES AND ASSOCIATIONS OF A UNISEXUAL-BISEXUAL COMPLEX OF POECILIA (PISCES: POECILIIDAE) FROM NORTHEASTERN MEXICO.
Creator
KUCHARSKI, KRISTINE MARIE., Florida Atlantic University, Courtenay, Walter R. Jr., Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
Two gynogenetically reproducing unisexuals, the diploid Poecilia formosa and its associated triploid are sympatric to P. mexicana, a bisexual species, in northeastern Mexico. All compete for sperm from P. mexicana males. Field and laboratory experiments studied habitat. preferences and associations as mechanisms of reducing competition. A new tagging method was developed. Laboratory results (Phase One) indicated habitat preferences of each female type. Further studies (Phase Two) showed the...
Show moreTwo gynogenetically reproducing unisexuals, the diploid Poecilia formosa and its associated triploid are sympatric to P. mexicana, a bisexual species, in northeastern Mexico. All compete for sperm from P. mexicana males. Field and laboratory experiments studied habitat. preferences and associations as mechanisms of reducing competition. A new tagging method was developed. Laboratory results (Phase One) indicated habitat preferences of each female type. Further studies (Phase Two) showed the fishes remained together but each female type associated with its own kind. Shade and a gravel substrate were important habitat parameters. Specific habitat preferences may not be adaptive due to seasonal water fluctuations but there are different ecological preferences by each female type. Associations could account for Phase One laboratory results and ecological differences. Combined data indicate associations are the likely mechanism, but habitat preferences are possible. Seasonal factors and artificial conditions may have caused diverse results.
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Date Issued
1979
PURL
http://purl.flvc.org/fcla/dt/13960
Subject Headings
Ichthyology--Research
Format
Document (PDF)
SURVEY OF THE FISH FAUNA IN THE SHALLOW MARINE WATERS OF CLAM LAGOON, ADAK, ALASKA
Title
A SURVEY OF THE FISH FAUNA IN THE SHALLOW MARINE WATERS OF CLAM LAGOON, ADAK, ALASKA.
Creator
HANCOCK, MAX JAY., Florida Atlantic University, Courtenay, Walter R. Jr., Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
A seasonal sampling of fishes was collected by seine from the sand-gravel areas of Clam Lagoon, Adak, Alaska. The community structure was compared to the structure of communities described from surveys of other areas. The seasonality of the fish fauna was examined for possible relationships with three exogenous factors; salinity, temperature and wind velocity. Length frequency histograms and substrate preferences are presented for seven species. The shallow-water seasonality of 13 species is...
Show moreA seasonal sampling of fishes was collected by seine from the sand-gravel areas of Clam Lagoon, Adak, Alaska. The community structure was compared to the structure of communities described from surveys of other areas. The seasonality of the fish fauna was examined for possible relationships with three exogenous factors; salinity, temperature and wind velocity. Length frequency histograms and substrate preferences are presented for seven species. The shallow-water seasonality of 13 species is presented. The ontogenetic and seasonal diets of seven species are discussed.
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Date Issued
1975
PURL
http://purl.flvc.org/fcla/dt/13711
Subject Headings
Fish populations--Alaska--Clam Lagoon, Adak
Format
Document (PDF)
Comparison of the Growth and Structure of the Pseudobranchs of Two Carangid Fishes
Title
Comparison of the Growth and Structure of the Pseudobranchs of Two Carangid Fishes.
Creator
Koenig, Christopher C., Courtenay, Walter R. Jr., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
The growth and structure of the pseudobranchs of Trachinotus carolinus and Oligoplites saurus is described, illustrated, and discussed with respect to their histology and gross morphology. Morphological and histological differences between the pseudobranchs of the two species occur in the associated arteries, filament growth, mitochondrial form, and in the epithelium bordering the pseudobranchs. The pseudobranch of T. carolinus is contrasted with a typical carangid pseudobranch, characterized...
Show moreThe growth and structure of the pseudobranchs of Trachinotus carolinus and Oligoplites saurus is described, illustrated, and discussed with respect to their histology and gross morphology. Morphological and histological differences between the pseudobranchs of the two species occur in the associated arteries, filament growth, mitochondrial form, and in the epithelium bordering the pseudobranchs. The pseudobranch of T. carolinus is contrasted with a typical carangid pseudobranch, characterized by O. saurus is thick and heavily vascularized and shows a tendency to atrophy with growth of the fish. The results of bilateral pseudobranchectomy differed between adults and juveniles. All the fish became blind; however, only the adults displayed buoyancy problems and permanent chromatophore expansion.
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Date Issued
1969
PURL
http://purl.flvc.org/fau/fd/FA00000781
Subject Headings
Carangidae--Anatomy, Florida pompano--Anatomy
Format
Document (PDF)
THERMALLY INDUCED VARIATIONS IN VERTEBRAL NUMBER IN LUCANIA PARVA BAIRD (ANTHERINIFORMES: CYPRINODONTIDAE) REARED IN THE LABORATORY
Title
THERMALLY INDUCED VARIATIONS IN VERTEBRAL NUMBER IN LUCANIA PARVA BAIRD (ANTHERINIFORMES: CYPRINODONTIDAE) REARED IN THE LABORATORY.
Creator
MCCARTHY, LINDA J., Florida Atlantic University, Courtenay, Walter R. Jr., Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
Embryos of Lucania parva Baird from two sites in the Florida Keys were raised in four temperature regimes, 18°, 22°, 26°, and 30°C to determine the response of vertebral numbers to different incubation temperatures. The result was in inverse linear relationship, with vertebral numbers increasing with decreasing temperature. Temperature modified the developmental rates, causing the embryos in the warm temperatures to hatch earlier than those in the cold temperatures.
Date Issued
1978
PURL
http://purl.flvc.org/fcla/dt/13951
Subject Headings
Biology, Zoology
Format
Document (PDF)