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- Title
- Activity patterns of green iguana (Iguana iguana) at Hugh Taylor Birch State Park, Fort Lauderdale, Florida.
- Creator
- Sekscienski, Stacey R., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Activity patterns of Iguana iguana from two locations within Hugh Taylor Birch State Park, Fort Lauderdale, Florida were documented and examined. Between May 1, 2006 to April 20, 2007, I. iguana were observed on a routine basis and activities were documented as one of six major activity categories (basking, locomotion, foraging, resting, visual signaling, and other). Data was analyzed to determine differences between activity patterns of I. iguana relative to sites, seasons, and size category...
Show moreActivity patterns of Iguana iguana from two locations within Hugh Taylor Birch State Park, Fort Lauderdale, Florida were documented and examined. Between May 1, 2006 to April 20, 2007, I. iguana were observed on a routine basis and activities were documented as one of six major activity categories (basking, locomotion, foraging, resting, visual signaling, and other). Data was analyzed to determine differences between activity patterns of I. iguana relative to sites, seasons, and size category within the park. Iguana iguana spent more time basking at Site 1 than Site 2. Size 4 animals which consisted of dominant adult males, spent more time basking than other males and adult females. Size 4 animals also spent less time foraging than hatchlings, juveniles, and other adults. These results complement the existing research on behavior of I. iguana and may be useful in determining invasive control efforts of I. iguana in Florida.
Show less - Date Issued
- 2012
- PURL
- http://purl.flvc.org/FAU/3359162
- Subject Headings
- Green iguana, Behavior, Adaptation (Biology)
- Format
- Document (PDF)
- Title
- EVOLVING RESPONSE OF THE WOOD STORK (MYCTERIA AMERICANA) TO URBANIZATION AND HYDROLOGICAL CHANGE IN THE UNITED STATES.
- Creator
- Shlepr, Katherine R., Gawlik, Dale E., Milton, Sarah L., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Urbanization and land development, climate change, pollution, the spread of invasive species, and sea level rise are unprecedented challenges that have led to 25% of avian species worldwide facing an elevated risk of extinction. Under rapidly changing environmental conditions, traditional population models are not ideal because they typically assume that demographic parameters are static in order to estimate the probability of species extinction over a chosen timeframe. This assumption...
Show moreUrbanization and land development, climate change, pollution, the spread of invasive species, and sea level rise are unprecedented challenges that have led to 25% of avian species worldwide facing an elevated risk of extinction. Under rapidly changing environmental conditions, traditional population models are not ideal because they typically assume that demographic parameters are static in order to estimate the probability of species extinction over a chosen timeframe. This assumption disregards species’ potential to adapt to environmental change; adaptations which could alter not only a species’ extinction outlook but also its legal protection status. The goal of my PhD research is to re-evaluate the risk of extinction of one threatened species, the Wood Stork (Mycteria americana), by accounting for potential adaptation in the context of planned and predicted changes in the southeastern United States. Since the 1970s, Wood Storks have shifted the timing of their breeding season, expanded their range northward and into novel habitats in urban areas, and begun consuming non-native fishes. I investigate these observations by comparing the physiology and diet of Wood Storks nesting in the historical core of their U.S. range (tree islands in the flooded Everglades marsh) with storks occupying novel habitats in urban and temperate locations. Faster growth rate, improved body condition, and increased survival by nestlings in urban areas would be evidence that colonies on the leading edge of the species’ range may be capable of sustaining growth of the whole population. In a third and final chapter, I forecast nest abundance and distribution patterns in the entirety of the U.S. range given various hydrological scenarios. Increased Wood Stork population size and stability are recovery criteria which must be met before the species can qualify for removal from the federal Endangered Species List. More broadly, understanding Wood Stork response to human development in the Everglades illuminates general patterns in avian species response to extreme changes in landscape, and could serve as a framework for proactively incorporating evolutionary potential into the framework of Endangered Species Act recovery in other species which have a high adaptive capacity.
Show less - Date Issued
- 2022
- PURL
- http://purl.flvc.org/fau/fd/FA00013916
- Subject Headings
- Wood stork, Urbanization, Adaptation (Biology), Wildlife conservation
- Format
- Document (PDF)
- Title
- Hydrodynamic functions of the wing-shaped heads of hammerhead sharks.
- Creator
- Barousse, Julien., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
The hydrodynamics of three different shark heads: Eusphyra blochii (Winghead shark), Carcharhinus acronotus (Blacknose shark) and Sphyrna tiburo (Bonnethead shark) were investigated. Force transducer measurement was used to explore how the cephalofoil (wing-shaped head) affects maneuverability and efficiency. As the dynamic behavior of maneuvering wings differs from that of the steady state motion, experiments have been conducted to simulate: 1) steady-state (no yaw motion) constant velocity...
Show moreThe hydrodynamics of three different shark heads: Eusphyra blochii (Winghead shark), Carcharhinus acronotus (Blacknose shark) and Sphyrna tiburo (Bonnethead shark) were investigated. Force transducer measurement was used to explore how the cephalofoil (wing-shaped head) affects maneuverability and efficiency. As the dynamic behavior of maneuvering wings differs from that of the steady state motion, experiments have been conducted to simulate: 1) steady-state (no yaw motion) constant velocity swimming, 2) constant forward velocity with yawing motion of the head and 3) turning maneuvers. Different range of velocities, angle of attack, yaw frequency and yaw amplitude were tested. Drag and lift coefficients were calculated and compared. The lift coefficient of Winghead shark is much higher compared to the other sharks. The lift-to-drag ratio showed that the Winghead shark has a hydrodynamic advantage compared to Blacknose shark and Bonnethead shark.
Show less - Date Issued
- 2009
- PURL
- http://purl.flvc.org/FAU/2795459
- Subject Headings
- Aquatic animals (Physiology), Adaptation (Biology), Sharks, Locomotion, Predation (Biology)
- Format
- Document (PDF)
- Title
- Do Fiddler Crab Larvae Show Phenotypic Plasticity?.
- Creator
- Christopher, Catherine E., Salmon, Michael, Florida Atlantic University
- Abstract/Description
-
Larval release by adult fiddler crabs occurs during the ebbing tides, but its timing relative to the day-night and tidal amplitude cycles depends upon tidal form (e.g., shows phenotypical plasticity). Crabs (Uca thayeri) from Florida's East Coast are exposed to semidiurnal tides and release their larvae at night, whereas crabs from Florida's West Coast exposed to mixed tides release their larvae during the afternoon. The purpose of this study was to determine whether the larvae could hatch at...
Show moreLarval release by adult fiddler crabs occurs during the ebbing tides, but its timing relative to the day-night and tidal amplitude cycles depends upon tidal form (e.g., shows phenotypical plasticity). Crabs (Uca thayeri) from Florida's East Coast are exposed to semidiurnal tides and release their larvae at night, whereas crabs from Florida's West Coast exposed to mixed tides release their larvae during the afternoon. The purpose of this study was to determine whether the larvae could hatch at times other than those correlated with the tidal form at their location. Clusters of eggs at similar stages of development, 24-72 h in advance of release, were reciprocally transferred between females from each coast. Release ofboth the transferred larvae and maternal clutch occurred synchronously, and at the time dictated by the female's tidal regime. These results suggest that larvae are phenotypically plastic with respect to hatching time and can either delay (West coast) or advance (East coast) their response to release signals from females.
Show less - Date Issued
- 2007
- PURL
- http://purl.flvc.org/fau/fd/FA00000733
- Subject Headings
- Cell differentiation, Adaptation (Biology), Evolution (Biology), Phenotypic plasticity
- Format
- Document (PDF)
- Title
- Visual and electrosensory ecology of batoid elasmobranchs.
- Creator
- Bedore, Christine N., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The electrosensory and visual adaptations of elasmobranchs to the environment have been more studied than most other senses, however, work on these senses is mostly limited to descriptive analyses of sensitivity, morphology, and behavior. The goal of this work was to explore electrosensory and visual capabilities in a more ecological context. To gain an understanding of the content of bioelectric signals, the magnitude and frequency of these stimuli were recorded from a broad survey of...
Show moreThe electrosensory and visual adaptations of elasmobranchs to the environment have been more studied than most other senses, however, work on these senses is mostly limited to descriptive analyses of sensitivity, morphology, and behavior. The goal of this work was to explore electrosensory and visual capabilities in a more ecological context. To gain an understanding of the content of bioelectric signals, the magnitude and frequency of these stimuli were recorded from a broad survey of elasmobranch prey items... Color vision adaptations also correlated to the photic environment of each species; cownose rays inhabit turbid, green-dominated waters and had two cone visual pigments that maximize contrast of objects against the green background... Yellow stingrays were trichromatic and likely possess the ability to discriminate colors in their clear, reef and seagrass habitats, which are spectrally rich. Both species showed evidence of ultraviolet sensitivity, which may aid in predator and conspecific detection as an enhanced communication channel. Future studies should investigate the integration of sensory input and sensory involvement in intraspecific communication to gain more insight into ecological adaptations.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3362337
- Subject Headings
- Visual discrimination, Adaptation (Biology), Animal ecophysiology, Chondrichthyes, Physiology
- Format
- Document (PDF)
- Title
- Sun compass orientation in juvenile green sea turtles (Chelonia mydas).
- Creator
- Mott, Cody Robert., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Recent studies show that sea turtles use both magnetic and visual cues to successfully orient. Juvenile green sea turtles from the near shore reefs of Palm Beach County, Florida were brought to the lab to determine whether the sun could serve as a visual orientation cue. When tethered during the day in a large outdoor tank west of the ocean, the turtles oriented east to northeast. To determine whether the sun's position was used to maintain their heading, I altered the turtles' perception of...
Show moreRecent studies show that sea turtles use both magnetic and visual cues to successfully orient. Juvenile green sea turtles from the near shore reefs of Palm Beach County, Florida were brought to the lab to determine whether the sun could serve as a visual orientation cue. When tethered during the day in a large outdoor tank west of the ocean, the turtles oriented east to northeast. To determine whether the sun's position was used to maintain their heading, I altered the turtles' perception of time by entraining them to a light cycle advanced by 7 h relative to the natural cycle. When tested afterward in the same outdoor tank the turtles oriented northwest, the predicted direction after compensating for the sun's movement over 7 h across the sky. Orientation was unchanged when the turtles bore magnets that negated the use of magnetic cues. These results are consistent with the hypothesis that the turtles used the sun for orientation.
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/2705073
- Subject Headings
- Animal orientation, Adaptation (Biology), Animal navigation, Sea turtles, Migration
- Format
- Document (PDF)
- Title
- Entrainment of larval release in an intertidal crab ( Uca thayeri) after exposure to a different tidal regime: Testing the "plasticity" hypothesis.
- Creator
- Weaver, Ann, Florida Atlantic University, Salmon, Michael
- Abstract/Description
-
Endogenous rhythms allow most organisms to synchronize their behavior and physiology with physical cycles that vary on a daily, lunar or annual cycle. Populations within species often show variation in the timing of functionally identical rhythms. This variation occurs because physical cycles may differ with geography. The purpose of this study was to determine whether hatching rhythms shown by fiddler crabs (Genus Uca) on one coastline could be entrained by the different tide patterns...
Show moreEndogenous rhythms allow most organisms to synchronize their behavior and physiology with physical cycles that vary on a daily, lunar or annual cycle. Populations within species often show variation in the timing of functionally identical rhythms. This variation occurs because physical cycles may differ with geography. The purpose of this study was to determine whether hatching rhythms shown by fiddler crabs (Genus Uca) on one coastline could be entrained by the different tide patterns present at another coastline. To test this I transferred breeding females (Uca thayeri) from mangroves on the west coast of Florida to mangroves on the east coast. On the west coast, females are exposed to "mixed" tides; most release their larvae during the day or night (early summer), or during the day (mid- to late summer). On the east coast, females are exposed to "semidiurnal" tides; they release their larvae between dusk and midnight. After four weeks of exposure to the East Coast tides, crabs from the West Coast showed hatching rhythms identical to the resident crabs. This change indicates that the crabs show behavioral (phenotypic) "plasticity". These observations provide further evidence for the adaptive value of behavioral plasticity.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/15774
- Subject Headings
- Fiddler crabs--Eggs, Fiddler crabs--Adaptation, Biological rhythms
- Format
- Document (PDF)
- Title
- A Novel Interaction: The thin stripe hermit Crab, Clibanarius vittatus, kills the Florida crown conch, Melongena corona, for its shell.
- Creator
- Cutter, Jennifer, Devlin, Donna, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The hermit crab Clibanarius vittatus kills Melongena corona solely to acquire a better fitting shell. This finding is contrary to previous studies, which found that hermit crabs of other species cannot kill gastropods or, in most instances, remove freshly dead gastropods from their shells. This interaction cannot be classified as predation because Melongena tissue was never consumed. Clibanarius killed Melongena only when by doing so they could trade up to a better fitting shell. It cannot be...
Show moreThe hermit crab Clibanarius vittatus kills Melongena corona solely to acquire a better fitting shell. This finding is contrary to previous studies, which found that hermit crabs of other species cannot kill gastropods or, in most instances, remove freshly dead gastropods from their shells. This interaction cannot be classified as predation because Melongena tissue was never consumed. Clibanarius killed Melongena only when by doing so they could trade up to a better fitting shell. It cannot be classified as competition because there is no opportunity for Melongena to gain from the interaction. Therefore the term “lethal eviction” is hereby proposed for this interaction. The ability to kill a gastropod to obtain a superior shell gives Clibanarius vittatus an evolutionary advantage over other hermit crab species. It is not known if the outcome of this interaction is widespread where both species occur or if it is confined to the study area.
Show less - Date Issued
- 2017
- PURL
- http://purl.flvc.org/fau/fd/FA00004925, http://purl.flvc.org/fau/fd/FA00004925
- Subject Headings
- Crabs--Behavior., Crab culture., Predation (Biology), Adaptation (Physiology), Aquatic ecology., Intertidal ecology., Conservation biology.
- Format
- Document (PDF)
- Title
- Effects of a severe winter on invasive green iguanas (Iguana iguana).
- Creator
- Campbell, Ashley B., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The green iguana (Iguana iguana) is an herbivorous lizard native to South America and is invasive in south Florida. The severe weather in January 2010 negatively impacted many species and significantly reduced the green iguana population, specifically adult females and juveniles of both sexes. Fifteen adult iguanas from two locations in Palm Beach County were tagged and had blood drawn for blood chemistry and HPLC steroid hormone analysis. Individuals were tracked for home range/territory...
Show moreThe green iguana (Iguana iguana) is an herbivorous lizard native to South America and is invasive in south Florida. The severe weather in January 2010 negatively impacted many species and significantly reduced the green iguana population, specifically adult females and juveniles of both sexes. Fifteen adult iguanas from two locations in Palm Beach County were tagged and had blood drawn for blood chemistry and HPLC steroid hormone analysis. Individuals were tracked for home range/territory analysis and behavioral observations. Blood chemistry values of cold-stunned individuals showed abnormal values similar to those reported in cold-stunned sea turtles. Territoriality and breeding behaviors, including nesting and head-bob displays, decreased or ceased during the following months. Steroid hormone concentrations were detected by HPLC and were not consistent with results from RIA studies in the literature.
Show less - Date Issued
- 2011
- PURL
- http://purl.flvc.org/FAU/3174507
- Subject Headings
- Weather, Environmental aspects, Adaptation (Biology), Climate changes, Environmental aspects, Conservation biology
- Format
- Document (PDF)
- Title
- Shifts in copepod grazing on varying concentrations of two bioluminescent dinoflagellate species.
- Creator
- Breitlow, Karen A., Florida Atlantic University, Widder, Edith A.
- Abstract/Description
-
Grazing on bioluminescent and nonluminescent prey by the copepod Acartia tonsa was examined to determine the effect dinoflagellate bioluminescence has on copepod feeding preferences and rates. The percentage of cells ml-1 remaining after 30 minutes of copepod grazing on the dinoflagellates Lingulodinium polyedrum and Pyrodinium bahamense in their bioluminescent and nonbioluminescent phases was used to compare results for concentrations of 10, 1,000, and 3,000 cells ml-1. The nonluminescent...
Show moreGrazing on bioluminescent and nonluminescent prey by the copepod Acartia tonsa was examined to determine the effect dinoflagellate bioluminescence has on copepod feeding preferences and rates. The percentage of cells ml-1 remaining after 30 minutes of copepod grazing on the dinoflagellates Lingulodinium polyedrum and Pyrodinium bahamense in their bioluminescent and nonbioluminescent phases was used to compare results for concentrations of 10, 1,000, and 3,000 cells ml-1. The nonluminescent diatom Thalassiosira eccentrica was later offered along with each of the dinoflagellates. When diatoms were offered with P. bahamense, the copepods consumed them in equal amounts regardless of bioluminescence at the lower concentration, while the higher concentration showed decreased grazing with bioluminescence. Nonbioluminescent L. polyedrum was consumed at a high rate for all concentrations, but grazing decreased once they were bioluminescent. Copepods switched to T. eccentrica once the dinoflagellates became bioluminescent, except at 3,000 cells ml-1, at which all grazing was reduced. These results indicate there may be a threshold concentration separating two functions of dinoflagellate bioluminescence.
Show less - Date Issued
- 2006
- PURL
- http://purl.flvc.org/fcla/dt/13357
- Subject Headings
- Dinoflagellates, Marine pharmacology, Bioluminescence, Marine animals--Behavior, Predation (Biology), Adaptation (Biology)
- Format
- Document (PDF)
- Title
- An Analysis of the Demography and Habitat Usage of Roatan's Spiny-tailed Iguana, Ctenosaura oedirhina.
- Creator
- Campbell, Ashley B., Maple, Terry, Gawlik, Dale E., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Psychology
- Abstract/Description
-
The Roatan Spiny-tailed Iguana (Ctenosaura oedirhina) is endemic to the 146-km2 island of Roatn, Honduras. Harvesting for consumption, fragmentation of habitat, and predation by domestic animals threaten this lizard. It is currently listed as Endangered by the International Union for Conservation of Nature (IUCN), as threatened by the Honduran government, and is on Appendix II of the Convention on International Trade in Endangered Species (CITES). This species has been geographically...
Show moreThe Roatan Spiny-tailed Iguana (Ctenosaura oedirhina) is endemic to the 146-km2 island of Roatn, Honduras. Harvesting for consumption, fragmentation of habitat, and predation by domestic animals threaten this lizard. It is currently listed as Endangered by the International Union for Conservation of Nature (IUCN), as threatened by the Honduran government, and is on Appendix II of the Convention on International Trade in Endangered Species (CITES). This species has been geographically fragmented and genetically isolated into small subpopulations that are declining in density. With data gathered from use/availability surveys, resource selection functions were used to identify habitats and environmental variables associated with their presence. Results indicate that protection from harvesting is the most important factor in determining their distribution. These high-density populations are currently restricted to ~0.6 km2. Organisms living in small, isolated populations with very restricted ranges are at higher risk of extirpation due to various direct and indirect forces. Mark-recapture-resight surveys and distance sampling have been used to monitor the populations since 2010 and 2012 respectively. The data show that the high-density populations are declining. The current population size is estimated to be 4130-4860 individuals in 2015. A population viability analysis (PVA) was conducted to identify the most pressing threats and specific life history traits that are affecting this decline. The analysis estimates that if current trends persist, the species will be extinct in the wild in less than ten years. Adult mortality is a main factor and female mortality specifically characterizes this decline. In order for this species to persist over the next fifty years, adult mortality needs to be reduced by more than 50%. A lack of enforcement of the current laws results in the persistence of the main threat, poaching for consumption, thus altering the species distribution and causing high adult mortality. This is complicated by social customs and a lack of post primary education. Management changes could mitigate this threat and slow the population decline. Recommendations include an education campaign on the island, increased enforcement of the current laws, and breeding of C. oedirhina in situ and ex situ for release into the wild.
Show less - Date Issued
- 2015
- PURL
- http://purl.flvc.org/fau/fd/FA00004486, http://purl.flvc.org/fau/fd/FA00004486
- Subject Headings
- Adaptation (Biology), Conservation biology -- Honduras -- Roatán Island, Iguanas -- Black spiny tailed -- Honduras -- Roatán Island -- Habitat., Roatán Island (Honduras) -- Ecology
- Format
- Document (PDF)
- Title
- Diet of the Purple Swamphen in south Florida and invasion pathways of nonnative avian species in Florida.
- Creator
- Callaghan, Corey, Gawlik, Dale E., Florida Atlantic University, Charles E. Schmidt College of Science, Center for Environmental Studies
- Abstract/Description
-
The spread of nonnative invasive species has become the second greatest threat to global biodiversity, making management of invasive species a critical component of the conservation of biodiversity worldwide. Managers and conservation biologists often lack basic life history data, as well as quantitative and theoretical models to predict risk of invasion or other negative effects. I contribute information to both categories by providing life history information (diet and morphology) of the...
Show moreThe spread of nonnative invasive species has become the second greatest threat to global biodiversity, making management of invasive species a critical component of the conservation of biodiversity worldwide. Managers and conservation biologists often lack basic life history data, as well as quantitative and theoretical models to predict risk of invasion or other negative effects. I contribute information to both categories by providing life history information (diet and morphology) of the Purple Swamphen (Porphyrio porphyrio) and by characterizing the invasion pathways that nonnative avian species in Florida follow. I found Purple Swamphens are predominantly eating and selecting for Eleocharis cellulosa. Additionally, there is a large amount of variation in nonnative avian species’ propensity to colonize natural habitat and the time it takes to do so. Nine out of 15 species investigated colonized natural habitat and the time it took them to do so ranged from 8 to 41 years. It is through a combination of various techniques that ecologists will begin to fully understand the importance of studying nonnative species as well as reducing the impact that nonnatives have on native ecosystems.
Show less - Date Issued
- 2015
- PURL
- http://purl.flvc.org/fau/fd/FA00004433, http://purl.flvc.org/fau/fd/FA00004433
- Subject Headings
- Birds--Behavior., Birds--Habitat., Adaptation (Biology), Biological invasions., Introduced organisms., Ecological risk assessment--Florida.
- Format
- Document (PDF)
- Title
- Risk assessment of the nonnative Argentine black and white Tegu, Salvator merianae, in South Florida.
- Creator
- Barraco, Liz Anne, Hughes, Colin, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The Argentine black and white tegu, Salvator merianae, is a nonnative species that has invaded parts of Florida. The potential impacts of this species on native Florida wildlife are not yet known. This study looks at the stomach contents of 169 S. merianae captured between 2011 and 2013 in south Florida to infer potential impacts of S. merianae and spatial or seasonal shifts in diet. Analysis of 169 GI tracts showed that S. merianae is an omnivorous, terrestrial forager with a broad dietary...
Show moreThe Argentine black and white tegu, Salvator merianae, is a nonnative species that has invaded parts of Florida. The potential impacts of this species on native Florida wildlife are not yet known. This study looks at the stomach contents of 169 S. merianae captured between 2011 and 2013 in south Florida to infer potential impacts of S. merianae and spatial or seasonal shifts in diet. Analysis of 169 GI tracts showed that S. merianae is an omnivorous, terrestrial forager with a broad dietary range which includes insects, fruits, plants, snails, crayfish, carrion, birds, small mammals, turtles, snakes, lizards, frogs and eggs. S. merianae diet composition varied with capture habitat, the fattest tegus were collected from disturbed/agricultural areas and these samples contained, primarily, gastropods and insects. Tegu dietary habits threaten local endangered and state listed species such as the American crocodile, Crocodylus acutus, and the Cape Sable seaside sparrow, Ammodramus maritimus mirabilis. Dedicated funds and efforts need to be focused on this species to limit its further spread and future impact on native species.
Show less - Date Issued
- 2015
- PURL
- http://purl.flvc.org/fau/fd/FA00004344, http://purl.flvc.org/fau/fd/FA00004344
- Subject Headings
- Adaptation (Biology), Ecological risk assessment -- Florida, Introduced reptiles -- Florida -- Identification, Lizards -- Florida -- Identification, Nonindigenous pests -- Geographical distribution, Predation (Biology)
- Format
- Document (PDF)
- Title
- Observations of immature sea turtles at a nearshore hardbottom developmental habitat in Palm Beach, Florida.
- Creator
- Garrido, Katharine., Harriet L. Wilkes Honors College
- Abstract/Description
-
Nearshore sabellariid worm rock reefs tracts along Florida's east cost provide developmental habitat for many juvenile green turtles.
- Date Issued
- 2007
- PURL
- http://purl.flvc.org/FAU/41004
- Subject Headings
- Sea turtles, Ecology, Adaptation (Biology), Wildlife conservation
- Format
- Document (PDF)
- Title
- Anatomy and physiology of the elasmobranch olfactory system.
- Creator
- Meredith, Tricia L., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The olfactory system is the most highly developed system for molecular sensing in vertebrates. Despite their reputation for being particularly olfactory driven, little is known about how this sense functions in elasmobranch fishes. The goal of this dissertation was to examine the morphology and physiology of elasmobranchs to compare their olfactory system with teleost fishes and more derived vertebrates. To test the hypotheses that elasmobranchs possess greater olfactory sensitivities than...
Show moreThe olfactory system is the most highly developed system for molecular sensing in vertebrates. Despite their reputation for being particularly olfactory driven, little is known about how this sense functions in elasmobranch fishes. The goal of this dissertation was to examine the morphology and physiology of elasmobranchs to compare their olfactory system with teleost fishes and more derived vertebrates. To test the hypotheses that elasmobranchs possess greater olfactory sensitivities than teleosts and that lamellar surface area is correlated to sensitivity, I compared the surface area of the olfactory lamellae and the olfactory sensitivities of five phylogenetically diverse elasmobranch species. The olfactory thresholds reported here (10-9 to 10-6 M) were comparable to those previously reported for teleosts and did not correlate with lamellar surface area. Since aquatic species are subject to similar environmental amino acid levels, they appear to have converged upon similar amino acid sensitivities. To test the hypothesis that elasmobranchs are able to detect bile salt odorants despite lacking ciliated olfactory receptor neurons (ORNs), the type of ORN that mediates bile salt detection in the teleosts, I quantified the olfactory specificity and sensitivity of two elasmobranch species to four, teleost-produced C24 bile salts. Both species responded to all four bile salts, but demonstrated smaller relative responses and less sensitivity compared to teleosts and agnathans. This may indicate that elasmobranchs don't rely on bile salts to detect teleost prey. Also, the olfactory system of elasmobranchs contains molecular olfactory receptors for bile salts independent of those that detect amino acids, similar to teleosts., In some elasmobranch species, each olfactory bulb (OB) is physically partitioned into two hemi-bulbs; however, the functional significance of this morphology is not fully understood. The organization of the OBs in three species with varying OB morphologies was examined to test the hypothesis that the elasmobranch OB is somatotopically arranged. Glomeruli in the OB received projections from ORNs in 3-4 olfactory lamellae situated immediately anterior. These results indicate a somatotopic arrangement of the elasmobranch OB, which may be unique among vertebrate olfactory systems and potentially led to the hemi-OB morphology.
Show less - Date Issued
- 2011
- PURL
- http://purl.flvc.org/FAU/3333058
- Subject Headings
- Condrichthyes, Sense organs, Condrichthyes, Physiology, Sharks, Physiology, Adaptation (Biology), Aquatic animals, Physiology
- Format
- Document (PDF)
- Title
- Cognitive and magnetosensory ecology of the yellow stingray, Urobatis jamaicensis.
- Creator
- Newton, Kyle C., Kajiura, Stephen M., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Elasmobranchs (sharks, skates, and rays) migrate across a wide range of spatiotemporal scales, display philopatry, seasonal residency, and maintain home ranges. Many animals use the Earth’s magnetic field to orient and navigate between habitats. The geomagnetic field provides a variety of sensory cues to magnetically sensitive species, which could potentially use the polarity, or intensity and inclination angle of the field, to derive a sense of direction, or location, during migration....
Show moreElasmobranchs (sharks, skates, and rays) migrate across a wide range of spatiotemporal scales, display philopatry, seasonal residency, and maintain home ranges. Many animals use the Earth’s magnetic field to orient and navigate between habitats. The geomagnetic field provides a variety of sensory cues to magnetically sensitive species, which could potentially use the polarity, or intensity and inclination angle of the field, to derive a sense of direction, or location, during migration. Magnetoreception has never been unequivocally demonstrated in any elasmobranch species and the cognitive abilities of these fishes are poorly studied. This project used behavioral conditioning assays that paired magnetic and reinforcement stimuli in order to elicit behavioral responses. The specific goals were to determine if the yellow stingray, Urobatis jamaicensis, could detect magnetic fields, to quantify the nature of the magnetic stimuli it could detect, and to quantify the learning and memory capabilities of this species. The results supported the original hypotheses and demonstrated that the yellow stingray could: discriminate between magnetic and non-magnetic objects; detect and discriminate between changes in geomagnetic field strength and inclination angle; and use geomagnetic field polarity to solve a navigational task. The yellow stingray learned behavioral tasks faster and retained the memories of learned associations longer than any batoid (skate or ray) to date. The data also suggest that this species can classify magnetic field stimuli into categories and learn similar behavioral tasks with increased efficiency, which indicate behavioral flexibility. These data support the idea that cartilaginous fishes use the geomagnetic field as an environmental cue to derive a sense of location and direction during migrations. Future studies should investigate the mechanism, physiological threshold, and sensitivity range of the elasmobranch magnetic sense in order to understand the effects of anthropogenic activities and environmental change on the migratory ability of these fishes.
Show less - Date Issued
- 2017
- PURL
- http://purl.flvc.org/fau/fd/FA00004883, http://purl.flvc.org/fau/fd/FA00004883
- Subject Headings
- Animal behavior., Animal migration., Magnetic fields--Physiological effect., Senses and sensation., Adaptation (Biology)
- Format
- Document (PDF)
- Title
- Effects of stressors on differential gene expression and secondary metabolites by Axinella corrugata.
- Creator
- Grima, Jennifer., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Sponges are an important source of bioactive marine natural products, or secondary metabolites. The common Caribbean reef sponge, Axinella corrugata, produces an antitumor and antibacterial chemical, stevensine. This study determined whether environmental stressors, such as elevated temperature and exposure to Amphibalanus amphitrite larvae, affect the production of stevensine by A.corrugata and if the stressors caused A.corrugata to exhibit differential gene expression. Temperature stress...
Show moreSponges are an important source of bioactive marine natural products, or secondary metabolites. The common Caribbean reef sponge, Axinella corrugata, produces an antitumor and antibacterial chemical, stevensine. This study determined whether environmental stressors, such as elevated temperature and exposure to Amphibalanus amphitrite larvae, affect the production of stevensine by A.corrugata and if the stressors caused A.corrugata to exhibit differential gene expression. Temperature stress resulted in no significant change in the production of stevensine; only two genes were significantly differentially expressed, including hsp70. Larval stressed resulted in increased production of stevensine and significant differential gene expression (more than seventy genes). This study suggests that A.corrugata may be resilient to elevations in temperature and that one of stevensine's roles in nature is as an antifoulant.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3360781
- Subject Headings
- Axinellida, Sponges, Marine pharmacology, Adaptation (Biology), Gene expression, Genetic regulation, Stress (Physiology), Ecophysiology
- Format
- Document (PDF)
- Title
- Visual adaptations in sharks, skates and rays.
- Creator
- McComb, Dawn Michelle, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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The central importance of vision to an organism is evident in the anatomical and physiological adaptations within the eye that can be correlated to the organism's behavior and ecology. The goal of this study was to perform a functional analysis of adaptations within the elasmobranch visual system. An integrative approach was used to examine morphological and physiological adaptations in several species and link these adaptations to phylogeny, locomotion, habitat, behavior and ecology....
Show moreThe central importance of vision to an organism is evident in the anatomical and physiological adaptations within the eye that can be correlated to the organism's behavior and ecology. The goal of this study was to perform a functional analysis of adaptations within the elasmobranch visual system. An integrative approach was used to examine morphological and physiological adaptations in several species and link these adaptations to phylogeny, locomotion, habitat, behavior and ecology. Functional aspects investigated were eye position, pupil shape, spectral sensitivity, temporal resolution, the extent of the visual field and ultimately the integration of the visual and electrosensory systems. The elasmobranch eye adapts to the light environment of its habitat. Sharks from similar habitats had similar spectral sensitivities such as the bonnethead and blacknose sharks, both maximally sensitive to blue light of 480 nm. The spectral sensitivity of the scalloped hammerhead, which lives in a different environment, was maximally sensitive to green light (530 nm). The temporal characteristics of the eye also matched habitat and lifestyle. Species experiencing variable light conditions exhibited increased critical flicker-fusion frequencies, such as the bonnethead (31 Hz) and scalloped hammerhead (27 Hz), in contrast to deeper or more nocturnal species such as the blacknose shark (18 Hz). Elasmobranch visual fields correlated to each species' lifestyle, habitat and foraging strategy. Expansive monocular views, including a 360° panoramic view in the yellow stingray, were measured in species that rely on vision for vigilance against predators., The Atlantic stingray possessed large binocular overlaps (72°), which provided depth perception useful for tracking prey. By comparison, the frontal binocular overlaps of hammerhead species were larger than sharks with a more conventional head shape.This study quantified the range of the electrosensory system and the exte the visual field of several shark species, confirming both systems overlap around the head facilitating near seamless visual and electrosensory sensory function relevant to prey detection. The findings of this study indicate that ambient environmental light strongly influenced the function of the elasmobranch eye and that the extent of species' visual fields correlated with aspects of their morphology, locomotion and ecology.
Show less - Date Issued
- 2009
- PURL
- http://purl.flvc.org/FAU/216410
- Subject Headings
- Visual discrimination, Chondrichthyes, Embryology, Form perception, Adaptation (Biology), Aquatic animals, Physiology
- Format
- Document (PDF)
- Title
- Activity and Habitat Selection by Loggerhead (Caretta caretta L.) and Green Turtle (Chelonia mydas. L.) Hatchlings: A Laboratory and Field Study.
- Creator
- Smith, Morgan M., Salmon, Michael, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
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Loggerhead and green turtle neonates migrate from Florida's coast during a 24-36 h frenzy. Post-frenzy loggerheads are often found in flotsam (Sargassum), while postfrenzy green turtles "disappear." This study compared the frenzy and post-frenzy activity of each species, their response to flotsam (in the laboratory and field), and the role of experience in habitat selection. Both species were most active during day I; activity thereafter declined (especially in loggerheads). Inactive...
Show moreLoggerhead and green turtle neonates migrate from Florida's coast during a 24-36 h frenzy. Post-frenzy loggerheads are often found in flotsam (Sargassum), while postfrenzy green turtles "disappear." This study compared the frenzy and post-frenzy activity of each species, their response to flotsam (in the laboratory and field), and the role of experience in habitat selection. Both species were most active during day I; activity thereafter declined (especially in loggerheads). Inactive loggerheads occupied Sargassum and open water (day or night) whereas inactive green turtles occupied Sargassum by day and both habitats at night. Exposure to Sargassum had no effect on the later habitat choices ofloggerheads, while exposed green turtles preferred Sargassum over plastic plants. In the field, both species preferred flotsam to open water, but occupied distinct microhabitats. Loggerheads preferred the mat surface while green turtles hid within the mat. Differences in activity and habitat selection likely reflect species-specific migratory and anti-predator strategies.
Show less - Date Issued
- 2007
- PURL
- http://purl.flvc.org/fau/fd/FA00000832
- Subject Headings
- Sea turtles--Ecology--Case studies, Wildlife conservation--Case studies, Habitat partitioning (Ecology), Adaptation (Biology)
- Format
- Document (PDF)
- Title
- Pelvic fin locomotion in batoids.
- Creator
- Macesic, Laura Jane., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Although most batoids (skates and rays) are benthic, only the skates (Rajidae) have been described as performing benthic locomotion, termed 'punting'. While keeping the rest of the body motionless, the skate's specialized pelvic fins are planted into the substrate and then retracted caudally, which thrusts the body forward. This may be advantageous for locating and feeding on prey, avoiding predators, and reducing energetic costs. By integrating kinematic, musculoskeletal, material properties...
Show moreAlthough most batoids (skates and rays) are benthic, only the skates (Rajidae) have been described as performing benthic locomotion, termed 'punting'. While keeping the rest of the body motionless, the skate's specialized pelvic fins are planted into the substrate and then retracted caudally, which thrusts the body forward. This may be advantageous for locating and feeding on prey, avoiding predators, and reducing energetic costs. By integrating kinematic, musculoskeletal, material properties, and compositional analyses across a range of morphologically and phylogenetically diverse batoids, this dissertation (i) demonstrates that punting is not confined to the skates, and (ii) provides reliable anatomical and mechanical predictors of punting ability. Batoids in this study performed true punting (employing only pelvic fins), or augmented punting (employing pectoral and pelvic fins). Despite the additional thrust from the pectoral fins, augmented punters failed to exceed the punting c apabilities of the true punters. True punters' pelvic fins had greater surface area and more specialized and robust musculature compared to the augmented punters' fins. The flexural stiffness of the main skeletal element used in punting, the propterygium, correlated with punting ability (3.37 x 10-5 - 1.80 x 10-4 Nm2). Variation was due to differences in mineral content (24.4-48-9% dry mass), and thus, material stiffness (140-2533 MPa), and second moment of area. The propterygium's radius-to-thickness ratio (mean = 5.52 +-0.441 SE) indicated that the propterygium would support true and augmented punters, but not non-punters, in an aquatic environment. All propterygia would fail on land. Geometric and linear morphometric analyses of 61 batoid pelvic girdles demonstrated that pelvic girdle shape can predict punting and swimming ability and taxonomic attribution to Order., Characteristics of true punters' pelvic girdles, such as laterally facing fin articulations, large surface area formuscle attachment, and tall lateral pelvic processes are similar to characteristics of early sprawled-gait tetrapods' pelvic girdles. This dissertation demonstrates that punting is common in batoids, illustrates the convergent evolution of true punter and early tetrapod pelvic anatomy, and gives possible explanations for the restriction of elasmobranchs to aquatic habitats.
Show less - Date Issued
- 2011
- PURL
- http://purl.flvc.org/FAU/3171678
- Subject Headings
- Sharks, Ecology, Fins, Anatomy, Adaptation (Biology), Aquatic animals, Physiology, Fishes, Locomotion
- Format
- Document (PDF)