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Behavior Of The American Alligator In A Louisiana Freshwater Marsh., William Lee Rootes
Behavior Of The American Alligator In A Louisiana Freshwater Marsh., William Lee Rootes
LSU Historical Dissertations and Theses
Stomachs from 706 alligators (Alligator mississippiensis) harvested from a southern Louisiana fresh marsh in 1987 and 1988 were examined for web tags from smaller marked alligators. Alligators $$2.73 m TL) were significantly more cannibalistic than smaller alligators (P $<$ 0.0001). Males and females were cannibalized in the same proportion they occurred in the population. Cannibalism mortality appeared to be distributed proportionately among all cohorts in the 0.35-2.12 m TL size classes resulting in a relatively uniform reduction across the group. Cannibalism was found to be an important population regulating mechanism, accounting for an estimated 50.2% of total hatchling mortality and 70.1% of total mortality in age 11 months and older alligators. Male growth rates in both a palustrine marsh (Lacassine National Wildlife Refuge) and estuarine marsh (Rockefeller Refuge) marsh types were greater than female rates (P $<$ 0.0001). Growth rates and weight-length ratios of alligators in estuarine marsh were greater than those of alligators in palustrine marsh (P $<$ 0.0001). Age specific fecundity and survivorship rates of alligators in the palustrine marsh were less than alligators in the estuarine marsh. The home range size and activity pattern of adult female alligators of different reproductive status were compared among seasons of the year. Home range size (P = 0.54) and minimum average daily movement rates (P = 0.85) did not differ between nesting and non-nesting radio-collared females during the summer nesting season. No difference was found between females with and without broods in the two variables during the fall brooding season. Adult radio-collared female alligators ranged over larger areas and had greater daily average daily movement rates during the spring breeding season than during any other season of the year (P $<$ 0.01). Annual home range size of the 15 adult female alligators monitored during the study was 36.2 $\pm$ 42.6 (SD) ha.
Physiological And Behavioral Responses To Aerial Exposure In The Asian Clam, Corbicula Fluminea (Muller)., Roger Anthony Byrne
Physiological And Behavioral Responses To Aerial Exposure In The Asian Clam, Corbicula Fluminea (Muller)., Roger Anthony Byrne
LSU Historical Dissertations and Theses
Aerially exposed, bivalve molluscs face opposing problems of preventing water loss, and maintaining metabolism. Because of the unpredictability of emersion duration, most freshwater bivalve families are capable of extensive emersion tolerance. Corbicula fluminea (Muller) is a relatively recent invader of freshwater and shares many physiological features with its estuarine ancestors. It might be expected to be intermediate in its emersion responses between those of more ancient freshwater forms, and those of estuarine clams. In air, C. fluminea displayed ventilatory behaviors which were associated with high rates of aerial O$\sb2$ uptake and CO$\sb2$ release. Normoxically exposed clams had bursts of heat …
A Distributional Analysis Of The Warblers Of The West Indies. (Volumes I And Ii)., David Neal Pashley
A Distributional Analysis Of The Warblers Of The West Indies. (Volumes I And Ii)., David Neal Pashley
LSU Historical Dissertations and Theses
Wood-warblers (Aves:Emberizidae:Parulinae) are a conspicuous and perhaps declining component of the avifauna of North America and the Neotropics. The West Indies are home to 16 permanent resident species and have been included in the ranges of 40 migrant species. On the basis of specimens in the world's museums and published literature, I report the known status, seasonality, and natural history of warblers in the Virgin Islands (1 permanent resident; 29 migrants), the Western Caribbean (2;28), the Lesser Antilles (5;26), the Bahamas (5;38), Bermuda (0;38), Puerto Rico (3;30), Jamaica (2;32), Hispaniola (4;31), and Cuba (4;35). I grouped the migrants into nine …
The Systematics Of The Genus Thyanta Stal (Hemiptera:Heteroptera:Pentatomidae)., David Allen Rider
The Systematics Of The Genus Thyanta Stal (Hemiptera:Heteroptera:Pentatomidae)., David Allen Rider
LSU Historical Dissertations and Theses
The pentatomid genus Thyanta Stal is one of several large genera in the nominate subfamily and tribe. Thyanta belongs among those genera of Pentatomini lacking a spine or tubercle at the base of the third (second visible) abdominal sternite. The genus is divided into two subgenera: Phacidium Breddin, containing a single species, T. aeruginosa Berg; and the nominate subgenus, containing 36 species and one subspecies. The subgenus Thyanta is further divided into four species groups based primarily on differences and similarities in male and female genitalia. The perditor species group contains nine species and one subspecies, the maculata species group …
Salinity Effects On The Development And Larval Tolerance Of Five Species Of Echinoderms., Richard Allen Roller
Salinity Effects On The Development And Larval Tolerance Of Five Species Of Echinoderms., Richard Allen Roller
LSU Historical Dissertations and Theses
Salinity effects on the developmental rates, larval tolerances and various metabolic processes of five species of echinoderms were investigated. Development of Lytechinus variegatus (Lamarck), Strongylocentrotus droebachiensis (O. F. Muller, 1776), Strongylocentrotus purpuratus (Stimpson, 1857), Strongylocentrotus pallidus (G. O. Sars, 1871), and Pisaster ochraceus (Brandt, 1835) larvae were observed. Developmental rates and larval survival to metamorphosis of S. droebachiensis and S. pallidus varied directly with salinity and were well within the observed salinity tolerance and distributional limits for the adults. For each species, embryos and larvae at lower salinities (20, 22.5, and $25\sp{o}\!/\!\sb{oo})$ tended to develop more slowly than those at …
Geographic Variation In Morphology And Allozymes Within Tree Squirrels, Sciurus Niger And S. Carolinensis, Of The Lower Mississippi River Valley., Nancy D. Moncrief
Geographic Variation In Morphology And Allozymes Within Tree Squirrels, Sciurus Niger And S. Carolinensis, Of The Lower Mississippi River Valley., Nancy D. Moncrief
LSU Historical Dissertations and Theses
Geographic variation was studied in fox squirrels, Sciurus niger, and gray squirrels, S. carolinensis, by comparing patterns of differentiation within and between these two sympatric species. Patterns of variation were examined in light of the lower Mississippi River as a potential barrier to dispersal and gene flow in these squirrels. Differences within and between species were analyzed using morphologic (15 cranial and mandibular measurements) and allozymic (35 presumptive gene loci) characters. Geographic patterns of variation among populations were apparent in the morphology and allozymes of both species; patterns of differentiation in morphologic and allozymic characters are similar between species; however, …
Effects Of Riverine Barriers On Genetic Differentiation Of Amazonian Forest Undergrowth Birds (Peru)., Angelo Paul Capparella
Effects Of Riverine Barriers On Genetic Differentiation Of Amazonian Forest Undergrowth Birds (Peru)., Angelo Paul Capparella
LSU Historical Dissertations and Theses
The high frequency with which rivers delimit phenotypically differentiated bird taxa is unique to Amazonia, where major rivers often form the boundaries between allospecies and subspecies pairs of understory terra firme forest birds. In contrast, many such forest species with life history traits similar to these differentiated forms show no variation in plumage across even the largest rivers. To determine whether such species are nonetheless genetically differentiated, I obtained tissue samples from populations of forest understory birds from opposite banks of the Napo and Amazon rivers of northeastern Peru. These included three species that are not phenotypically differentiated across the …
Tolerance, Bioenergetics And Biochemical Composition Of The Blue Crab, Callinectes Sapidus Rathbun, Exposed To The Water-Soluble Fraction Of South Louisiana Crude Oil., Shiao Yu Wang
LSU Historical Dissertations and Theses
The tolerance, bioenergetics, growth, molting frequency and biochemical composition of juvenile blue crabs, Callinectes sapidus, exposed to the water-soluble fraction of South Louisiana crude oil were determined during a 21-d exposure period. Blue crabs were highly tolerant to petroleum hydrocarbons; the LC50 was 3927 ppb on day 21. Rates of energy intake decreased with increasing hydrocarbon concentration. Although energy expenditure rates of crabs exposed to 2504 ppb were not significantly higher than that of control crabs, they were significantly higher than those of crabs exposed to 820 and 1476 ppb. The resulting decrease in scope for growth was thus due …
Population Dynamics Of The Monogenea (Platyhelminthes) On The Bluegill, Lepomis Macrochirus, In Southern Louisiana., Leon F. Duobinis-Gray
Population Dynamics Of The Monogenea (Platyhelminthes) On The Bluegill, Lepomis Macrochirus, In Southern Louisiana., Leon F. Duobinis-Gray
LSU Historical Dissertations and Theses
Seven species of Monogenea of the subfamily Ancyrocephalinae were collected from 700 Lepomis macrochirus from two eutrophic localities in southern Louisiana. Host specimens were collected monthly from May 1982 through April 1984 from Pat's Bay and Spanish Lake. The relative densities of nonlarval Onchocleidus ferox, Actinocleidus fergusoni, Haplocleidus acer, H. dispar, Anchoradiscus triangularis, Cleidodiscus robustus, and C. nematocirrus were analysed for correlation with water temperature, significant differences in locality, temporal and spatial dynamics, and effect of host sex on population densities. The three more abundant species, O. ferox, A. fergusoni, and H. acer, were warm-water forms, whereas H. dispar and …
Karyology Of Lower Teleost Fishes (Clupeiformes, Taxonomy, Elopiformes, Phylogeny)., Albert John Doucette Jr
Karyology Of Lower Teleost Fishes (Clupeiformes, Taxonomy, Elopiformes, Phylogeny)., Albert John Doucette Jr
LSU Historical Dissertations and Theses
Karyotypes of nine species (Megalops atlanticus, Elops saurus, Brevoortia patronus, B. smithi, B. tyrannus, Dorosoma cepedianum, D. petenense, Harengula clupeola, and Anchoa mitchilli) and one hybrid (B. smithi x B. tyrannus) of teleost fishes revealed diploid complements ranging from 28 to 50 chromosomes and comprised of uniarmed elements or combinations of uniarmed and small and large biarmed elements. The occurance of large metacentric-submetacentric chromosomes was usually associated with a reduction in total chromosome number suggesting fusion events in the evolution of karyotypes from ancestral complements with 48 to 52 acrocentrics. Information from karyotypes is used to characterize species, genera, and …
Biochemical Systematics Of The Tyrannoidea (Aves) (Electrophoresis, Jackknifing, Phylogenetic Trees, Consensus Methods)., Scott Merrill Lanyon
Biochemical Systematics Of The Tyrannoidea (Aves) (Electrophoresis, Jackknifing, Phylogenetic Trees, Consensus Methods)., Scott Merrill Lanyon
LSU Historical Dissertations and Theses
The superfamily Tyrannoidea (Aves) has been the subject of numerous systematic investigations, yet the relationships among and within the five component families remain ambiguous. Relationships within the superfamily were investigated using starch gel electrophoresis of 20 enzyme loci in 14 cotinga genera, 12 manakin genera, the flycatcher genus Myiarchus, and each of the genera from the monogeneric families Phytotomidae and Dxyruncidae. Electrophoretic characters were found to contain considerable information concerning familial and subfamilial relationships within this New World assemblage. The Fitch-Margoliash "jackknife strict consensus tree" and a cladogram generated from the character state distributions were very similar and were used …
Molecular Studies Of Thamnophiine Snakes., Robin Lawson
Molecular Studies Of Thamnophiine Snakes., Robin Lawson
LSU Historical Dissertations and Theses
Variation in alleles at gene loci encoding proteins was used to determine zoogeographic and evolutionary differentiation in thamnophiine snakes. Differentiation among populations within a species, among species within a genus, and among genera was investigated. In the southern banded water snake, Nerodia fasciata, analysis by F-statistics and genetic distances of allele frequencies indicated that extensive differentiation has occurred between those forms adapted to a saltwater environment (N. f. clarkii and N. f. compressicauda) and those adapted to a freshwater environment (N. f. fasciata, N. f. confluens, and N. f. pictiventris). Habitat disturbance is imputed as the causal agent in the …
Life Cycle Of Alaria Marcianae In Louisiana (Trematoda, Transmammary, Milk-Borne)., Wesley Lawrence Shoop
Life Cycle Of Alaria Marcianae In Louisiana (Trematoda, Transmammary, Milk-Borne)., Wesley Lawrence Shoop
LSU Historical Dissertations and Theses
The life cycle of Alaria marcianae (Trematoda) as found in Louisiana involves the planorbid snail, Helisoma trivolvis, as first intermediate host; tadpoles of Rana catesbiana, R. clamitans, R. utricularia, Hyla cinerea, and Gastrophryne carolinensis as second intermediate hosts; a wide range of amphibian, reptilian, and mammalian paratenic hosts; and the bobcat (Lynx rufus), domestic cat (Felis domesticus), and juvenile raccoon (Procyon lotor) as definitive hosts. Eggs defecated by the definitive host require an incubation period of approximately 20 days; a free swimming miracidium hatches from each egg and must penetrate a snail within 24 hr or die; the miracidium transforms …
Circadian Systems In Development And Photoperiodism In Japanese Quail., Albert C. Russo Jr
Circadian Systems In Development And Photoperiodism In Japanese Quail., Albert C. Russo Jr
LSU Historical Dissertations and Theses
Section I: The daily rhythm of plasma levels of adrenal corticol hormones (ACH) differed in phase and amplitude in Japanese quail of different ages and reproductive condition. Treatment with thiouracil accelerated and thyroxine delayed maturation of the ACH rhythm and development of the reproductive system. In contrast to the ACH rhythm, the rhythm of plasma thyroxine concentrations was similar at all ages tested. Section II: The roles of circadian rhythms in photoperiodism as they relate to adrenal cortical hormone (ACH) were examined in male Japanese quail, Coturnix coturnix japonica. Plasma ACH concentration was found to undergo circadian variations, which varied …
An Analysis Of The Trematode Fauna Of Two Intercontinental Migrants: Tringa Solitaria And Calidris Melanotos (Aves: Charadriiformes) (Ecuador, Louisiana, South Dakota, Canada)., Erika Jansic Tallman
An Analysis Of The Trematode Fauna Of Two Intercontinental Migrants: Tringa Solitaria And Calidris Melanotos (Aves: Charadriiformes) (Ecuador, Louisiana, South Dakota, Canada)., Erika Jansic Tallman
LSU Historical Dissertations and Theses
One hundred ninety-seven Solitary Sandpipers, Tringa solitaria, and 213 Pectoral Sandpipers, Calidris melanotos, were examined for trematodes. Specimens were taken from the hosts' winter range in Ecuador, South America, during the fall and spring migrations from Louisiana and South Dakota in the United States, and from the breeding grounds of the Solitary Sandpiper in Ontario, Canada. The 13 species of trematodes recorded from the shorebirds included 5 that were common to both species of shorebirds: Tanaisia fedtschnkoi, Cyclocoelum obscurum, Paramonostomum sp., Leucochloridium variae, and Zonorchis microrochis. Of the remaining 8 species, Cyclocoelum brasilianum, Plagiorchis maculosus, Stephanoprora denticulata, and Eurytrema lubens …
Genetic And Molecular Genetic Studies In The Cytoplasmic Incompatibility System In The Mosquito Culex Pipiens., David Ray Mcgee
Genetic And Molecular Genetic Studies In The Cytoplasmic Incompatibility System In The Mosquito Culex Pipiens., David Ray Mcgee
LSU Historical Dissertations and Theses
An analysis of the cytoplasmic incompatibility system in Culex pipiens has been made. Both normal and antibiotic-resistant strains have been established using erythromycin, chloramphenicol and tetracycline. A complete genetic analysis has been made using all possible reciprocal crosses. Crosses between the normal strains show unidirectional compatibility. The genetic crosses involving the tetracycline-resistant strain show a reversal of the direction of compatibility when compared with those involving the untreated parental strain. Erythromycin and chloramphenicol-resistant strains exhibited no such change in direction of compatibility when compared with their respective untreated parental strains. Exceptional crossing relationships between chloramphenicol and tetracycline-resistant strains were found. …
Development Of The Cervical Region Of Chicken Embryos Studied Via The Teratogenic Effects Of Monocrotophos., Christina Irene Lusk
Development Of The Cervical Region Of Chicken Embryos Studied Via The Teratogenic Effects Of Monocrotophos., Christina Irene Lusk
LSU Historical Dissertations and Theses
No abstract provided.
Ecological Partitioning By Antbirds Of A Moist Tropical Forest In Amazonian Ecuador., Dan Allen Tallman
Ecological Partitioning By Antbirds Of A Moist Tropical Forest In Amazonian Ecuador., Dan Allen Tallman
LSU Historical Dissertations and Theses
No abstract provided.
Ultrastructure Of Purified Toxoplasma Gondii And Characterization Of Its Pellicle., Jean Carol Tryon
Ultrastructure Of Purified Toxoplasma Gondii And Characterization Of Its Pellicle., Jean Carol Tryon
LSU Historical Dissertations and Theses
No abstract provided.
Thyroid Hormones And Seasonality In The White-Throated Sparrow And Green Anole., Blaine Richard Ferrell
Thyroid Hormones And Seasonality In The White-Throated Sparrow And Green Anole., Blaine Richard Ferrell
LSU Historical Dissertations and Theses
No abstract provided.
Morphological And Behavioral Polymorphism In Poecilia Latipinna Males (Pisces: Poeciliidae)., Carol Louise Luckner
Morphological And Behavioral Polymorphism In Poecilia Latipinna Males (Pisces: Poeciliidae)., Carol Louise Luckner
LSU Historical Dissertations and Theses
No abstract provided.
Glugea Hertwigi (Protozoa: Microsporida) In Osmerus Mordax (Teleosteii: Osmeridae): Field Ecology, Laboratory Transmission And Ultrastructural Study Of Parasite Development And The Host Cell-Parasite Interface., Ann L. Scarborough
LSU Historical Dissertations and Theses
No abstract provided.
Ornithogeography Of The Southern Bahamas., Donald W. Buden
Ornithogeography Of The Southern Bahamas., Donald W. Buden
LSU Historical Dissertations and Theses
No abstract provided.
A Systematic Analysis Of The Endemic Avifauna Of The Hawaiian Islands., Harold Douglas Pratt Jr
A Systematic Analysis Of The Endemic Avifauna Of The Hawaiian Islands., Harold Douglas Pratt Jr
LSU Historical Dissertations and Theses
No abstract provided.
Life History And Seasonal Abundance Patterns Of Aquatic Oligochaeta In Four Southeastern Louisiana Habitats., Michael Simpson Loden
Life History And Seasonal Abundance Patterns Of Aquatic Oligochaeta In Four Southeastern Louisiana Habitats., Michael Simpson Loden
LSU Historical Dissertations and Theses
No abstract provided.
Life History Studies Of Three Digenetic Trematodes (Digenea: Cryptogonimidae)., George Jerome Greer
Life History Studies Of Three Digenetic Trematodes (Digenea: Cryptogonimidae)., George Jerome Greer
LSU Historical Dissertations and Theses
No abstract provided.
Regulation Of Mammalian Hibernation., John Thomas Burns
Regulation Of Mammalian Hibernation., John Thomas Burns
LSU Historical Dissertations and Theses
No abstract provided.
A Seasonal And Ecological Survey Of Freshwater Limpet Snails And Their Digenetic Trematode Parasites In Southeastern Louisiana., Hugh Michael Turner
A Seasonal And Ecological Survey Of Freshwater Limpet Snails And Their Digenetic Trematode Parasites In Southeastern Louisiana., Hugh Michael Turner
LSU Historical Dissertations and Theses
No abstract provided.
Craniometric Variation In Seven Species Of Small Mammals In Relation To Environmental And Competitive Factors., Kim Rutherford Thomas
Craniometric Variation In Seven Species Of Small Mammals In Relation To Environmental And Competitive Factors., Kim Rutherford Thomas
LSU Historical Dissertations and Theses
No abstract provided.
Biology Of A Limicolous Megadrile (Annelida: Oligochaeta) From Louisiana., Michael Lee Mcmahan
Biology Of A Limicolous Megadrile (Annelida: Oligochaeta) From Louisiana., Michael Lee Mcmahan
LSU Historical Dissertations and Theses
No abstract provided.