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- Title
- A comparison of the thermal bleaching response of the zoanthid Palythoa caribaeorum from three geographically different regions in south Florida.
- Creator
- Kemp, Dustin W., Florida Atlantic University, Cook, Clayton B., Brooks, W. Randy, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Coral bleaching involves the loss of symbiotic algae (zooxanthellae) from reef corals and other cnidarians during periods of environmental stress, particularly elevated temperature. In this study the thermal bleaching responses of the zoanthid Palythoa caribaeorum from three populations along the southeast coast of Florida were compared. Winter (2002--2003) and summer (2003) samples from three geographically separate sites were exposed to increased temperatures and the loss of zooxanthellae...
Show moreCoral bleaching involves the loss of symbiotic algae (zooxanthellae) from reef corals and other cnidarians during periods of environmental stress, particularly elevated temperature. In this study the thermal bleaching responses of the zoanthid Palythoa caribaeorum from three populations along the southeast coast of Florida were compared. Winter (2002--2003) and summer (2003) samples from three geographically separate sites were exposed to increased temperatures and the loss of zooxanthellae was measured. Zooxanthellae populations were sampled and identified using PCR-DGGE. The results showed that samples of P. caribaeorum from reefs that experience smaller annual thermal ranges released the most zooxanthellae. Seasonal comparisons revealed winter samples experienced a greater amount of zooxanthellae loss than summer samples. P. caribaeorum was found to harbor two genetic strains of zooxanthellae, C1 and D1a. Colonies either contained monotypic populations of these, or a combination of both.
Show less - Date Issued
- 2003
- PURL
- http://purl.flvc.org/fcla/dt/13053
- Subject Headings
- Zoanthinaria, Seawater--Thermal properties, Zooxanthellales
- Format
- Document (PDF)
- Title
- Functional aspects of behavior and morphology in the decorator crab Microphrys Bicornutus (Latreille, 1825) (Crustacea: Brachyura: Mithracidae).
- Creator
- Salazar, Monique Alexandra, Brooks, W. Randy, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Masking or decorator crabs, conceal themselves partially through camouflage, by selecting or indiscriminately attaching materials from their environment to their exoskeleton. Functional aspects of decorating behavior and morphology in this group have not been documented. Using Microphrys bicornutus as a model species, this dissertation demonstrates clearly that decorating is an advantageous phenotype that has evolved to serve several functions. Decorating is a complex behavior that begins...
Show moreMasking or decorator crabs, conceal themselves partially through camouflage, by selecting or indiscriminately attaching materials from their environment to their exoskeleton. Functional aspects of decorating behavior and morphology in this group have not been documented. Using Microphrys bicornutus as a model species, this dissertation demonstrates clearly that decorating is an advantageous phenotype that has evolved to serve several functions. Decorating is a complex behavior that begins when a crab approaches an algal substrate and results in the attachment of algae to hooked setae on the exoskeleton. Once decorated, crabs remain motionless on the substrate until disturbed or until another behavior is initiated. This was confirmed for M. bicornutus, as crabs spent a significant amount of time feeding, remaining motionless, picking, and walking when compared to decorating. Crabs displayed agonistic behaviors during encounters with conspecifics conspecifics. These included both active aggressive behavior and display behavior. Crabs showed a decrease in motility during these encounters, helping maintain dispersed distributions, thereby decreasing intrsapecific encounters in the field. Trials were done to determine the effect of conspecifics, predators and feeding preferences on algal utilization. M. bicornutus showed a significant decrease in the amount of algae used for decoration in the highest density trials (i.e., 4 and 8 crabs). Agonistic displays and aggressive behavior between these crabs likely affected the time available for decorating. Decorated crabs isolated from an algal substrate were more likely to survive in the presence of either of two sympatric fish predators. Thus, being protected by the algal decoration on their exoskeletons. Trials also showed a parallel between algal consumption and algal materials used for decoration. In addition to its protective function, algae used by M. bicornutus for decoration simultaneously serve as short term food supplies for the crabs. Eleven morphologically complex structures were identified and mapped on the exoskeleton. Hooked setae were the primary structures used to attach algae to the crab’s body. Ten additional setal structures were present, including two novel types of setae. On the basis of location and morphological variation exhibited among these latter structures, a primary sensory function may be inferred.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fau/fd/FA0004056
- Subject Headings
- Animal behavior, Camouflage (Biology), Crabs -- Behavior, Marine ecology, Predation (Biology)
- Format
- Document (PDF)
- Title
- Mechanisms of Coexistence Between Two Octopus Species In A South Florida Lagoon.
- Creator
- Bennice, Chelsea, Brooks, W. Randy, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Theoretically, sympatric species must partition resources or space to allow for coexistence. Determining empirically the specific resources each species exploits and species’ interactions (e.g., intra- and interspecific competition) can sometimes be challenging, thus the data are relatively sparse for certain taxa. This paucity of data exists for octopuses. Therefore, I chose to study niches of two sympatric octopuses (Octopus vulgaris and Macrotritopus defilippi) in an intracoastal habitat....
Show moreTheoretically, sympatric species must partition resources or space to allow for coexistence. Determining empirically the specific resources each species exploits and species’ interactions (e.g., intra- and interspecific competition) can sometimes be challenging, thus the data are relatively sparse for certain taxa. This paucity of data exists for octopuses. Therefore, I chose to study niches of two sympatric octopuses (Octopus vulgaris and Macrotritopus defilippi) in an intracoastal habitat. Specifically, I assessed (1) spatial distribution of octopus home or “den” space, (2) habitat association, (3) octopus abundance, (4) foraging activity periods, (5) diet, and (6) associated substrates and behaviors used during foraging events. Octopus den locations were marked by GPS to quantify spatial patterns of both species and their spatial relationship to each other. Habitat associations were measured by quantifying photoquadrats of den and surrounding habitats. For foraging activity periods, a video camera was placed near an octopus den for 24-h observation to determine when each octopus species leaves/returns from foraging. Underwater video recording was used to determine associated foraging substrates and behaviors for both species. Prey remains from octopus’ dens and video recordings indicating prey consumption were used to determine diets of the two octopus species. Video recordings from the 24-h camera and foraging behavior events also provided observations of intra- and interspecific interactions. Results revealed that the two species are interspersed throughout the shallow Florida lagoon and are both abundant during the spring months (March, April, May). Although both species are interspersed throughout the lagoon, their den and surrounding habitat association differed. O. vulgaris was associated with hard bottom and M. defilippi was associated with soft bottom, thus they may not compete strongly for habitats. Each species used different foraging strategies and different primary prey, which may also lessen competition and facilitate coexistence. O. vulgaris had peak foraging activity during night hours, foraged mostly on hard bottom and mainly consumed bivalves while M. defilippi had peak foraging activity during day hours, foraged mostly on soft bottom and mainly consumed crustaceans. Octopuses also had species-specific foraging behaviors, with O. vulgaris using parachute attack and M. defilippi using flounder swimming and tripod stance. Additional intra- and interspecific interactions were video recorded and included: fishes following octopuses, predation attempts, agonistic encounters, cannibalism, and tactile communication. This study identified ecological and behavioral components that may facilitate coexistence of these sympatric species, provided insight into cephalopod niches and ecology, and provided baseline conservation requirements for sand-dwelling cephalopods, both of which may be using this site as a mating and nursery habitat.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013185
- Subject Headings
- Octopuses, Sympatry (Biology), Coexistence of species, Lagoons--Florida
- Format
- Document (PDF)
- Title
- The role of chemical and visual cues by two Sargassum shrimps in locating and selecting habitats.
- Creator
- Jobe, Corrine F., Florida Atlantic University, Brooks, W. Randy, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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The Sargassum community is comprised of a unique and diverse assemblage of organisms. Habitat detection by two of the most common invertebrates, Latreutes fucorum and Leander tenuicornis , was investigated. Results of this study do not support that either L. fucorum or L. tenuicornis respond to chemical cues released by the Sargassum habitat in the absence of other information. Habitat selection of both shrimp species was examined as well. Both L. fucorum and L. tenuicornis selected live...
Show moreThe Sargassum community is comprised of a unique and diverse assemblage of organisms. Habitat detection by two of the most common invertebrates, Latreutes fucorum and Leander tenuicornis , was investigated. Results of this study do not support that either L. fucorum or L. tenuicornis respond to chemical cues released by the Sargassum habitat in the absence of other information. Habitat selection of both shrimp species was examined as well. Both L. fucorum and L. tenuicornis selected live Sargassum over artificial Sargassum . Moreover, L. fucorum selected Sargassum natans over Sargassum fluitans when only visual cues were available, whereas large-sized L. tenuicornis selected S. fluitans under the same conditions. Conversely, habitat selection trials combining both chemical and visual cues resulted in no preference between the two Sargassum species by either shrimp species. Additional ecological factors that possibly influence habitat location and selection are discussed as well as the importance of Sargassum in terms of pelagic fisheries management.
Show less - Date Issued
- 2006
- PURL
- http://purl.flvc.org/fcla/dt/13381
- Subject Headings
- Habitat (Ecology), Sargassum, Marine chemical ecology, Animal behavior
- Format
- Document (PDF)
- Title
- THE CRITICAL ROLE OF INTERACTIONS BETWEEN ECOLOGICAL FOUNDATION SPECIES IN STRUCTURING A MANGROVE COMMUNITY.
- Creator
- Aquino-Thomas, Jessene, Brooks, W. Randy, Proffitt, C. Edward, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
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The main objective of this research was to analyze how well my proposed Foundation Species Interaction model explained the benthic communities found on red mangrove (Rhizophora mangle) prop roots. This research investigated the connections between the primary foundation species (mangroves), the dominant secondary foundations species (oysters, sponges, and barnacles), and the resulting biodiversity in order to understand the temporal and spatial variability of the ecosystems at different...
Show moreThe main objective of this research was to analyze how well my proposed Foundation Species Interaction model explained the benthic communities found on red mangrove (Rhizophora mangle) prop roots. This research investigated the connections between the primary foundation species (mangroves), the dominant secondary foundations species (oysters, sponges, and barnacles), and the resulting biodiversity in order to understand the temporal and spatial variability of the ecosystems at different community levels. Chapter 1 was dedicated to explaining my change in ecological theory, the Foundation Species Interaction model. The interactions included in the model between the foundations species that were examined were the mutualistic (+, +), commensal (+, 0), and parasitic (+, -) interactions. Chapter 2 focused on exploration of the mangrove ecosystem in Southeast Florida and establishing where the secondary foundation species and prop root epibionts where found along the latitudinal gradient. The survey investigated the connections between mangroves, the dominant secondary foundations species (e.g. oysters, sponges, and barnacles), and the resulting biodiversity to understand the temporal and spatial variability of the ecosystems at different community levels. Chapter 3 was dedicated to testing the Foundation Species Interaction model’s ability to predict the biodiversity along the latitudinal gradient of the survey. The difference in mangrove prop root communities were largely explained by where the communities laid along the latitudinal gradient and by secondary foundation species presence. The shift from one foundation species to another had sizable effects on biodiversity. Chapter 4 combined the Foundation Species Interaction model with the established predation hypothesis and tested their abilities to explain biodiversity along the latitudinal gradient. This allowed for shifts in community structure to be examined for top-down and bottom-up influences. Predation effects changed along the latitudinal gradient, as the predation effects changed so did the effects of each of the individual foundation species.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013561
- Subject Headings
- Mangrove ecology--Florida, Rhizophora mangle, Red mangrove--Ecology, Biodiversity & ecology
- Format
- Document (PDF)
- Title
- The fate of copper in flooded south Florida agricultural soils and its toxicological effects on the Florida apple snail, Pomacea paludosa.
- Creator
- Rogevich, Emily Catherine, Florida Atlantic University, Brooks, W. Randy, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Agricultural sites have been acquired under the Comprehensive Everglades Restoration Plan (CERP) for the creation of water storage areas. Copper desorption and toxicity to the Florida apple snail (Pomacea paludosa) were investigated using soils from these sites. Copper concentrations in II soils ranged from 5 to 234 mg/kg Cu dw, and when flooded, resulted in overlying water Cu concentrations from 9 to 308 11g/L Cu. Juvenile apple snails exposed to three flooded soils had high mortality and...
Show moreAgricultural sites have been acquired under the Comprehensive Everglades Restoration Plan (CERP) for the creation of water storage areas. Copper desorption and toxicity to the Florida apple snail (Pomacea paludosa) were investigated using soils from these sites. Copper concentrations in II soils ranged from 5 to 234 mg/kg Cu dw, and when flooded, resulted in overlying water Cu concentrations from 9 to 308 11g/L Cu. Juvenile apple snails exposed to three flooded soils had high mortality and decreased growth within 9 to 16 days in two ofthe three soils examined. To assess Cu toxicity to the apple snail at various life stages and water quality parameters, 96 hour acute toxicity studies were conducted. Copper was more toxic to juvenile than adult apple snails. Copper toxicity increased as pH decreased and decreased as DOC increased. Hardness had no effect on Cu toxicity to the apple snail. Copper toxicity was a function of organism age, DOC and pH. Copper accumulation by juvenile and adult apple snails was determined for multiple exposure pathways. For 28 days, juvenile snails were exposed to aqueous Cu and adult snails were exposed to Cu contaminated soil, water and food. Whole body Cu in juvenile snails increased with time. The mean Cu bioconcentration factor (BCF) for juvenile snails was 1493. For adult snails, the dietary exposure pathway resulted in the highest bioaccumulation factor (BAF). Most Cu accumulated in soft tissue. During a chronic aqueous exposure, apple snails exposed to 8-16 flg /L Cu for 9 months had high Cu accumulation and significantly reduced clutch production (8-16 flg /L) and egg hatching (16 flg/L ). Chronic Cu exposure initially decreased growth in juvenile snails, but growth rebounded by adulthood and snails appeared to acclimate to chronic Cu exposure. When apple snails with high tissue Cu were fed to redear sunfish (Lepomis microlophus) Cu transfer was minimal, suggesting that the risk of trophic transfer (bioaccumulation) of Cu from the snail to redear sunfish is low and that biomagnification is unlikely. It is uncertain if other apple snail predators would be at risk for dietary Cu transfer.
Show less - Date Issued
- 2008
- PURL
- http://purl.flvc.org/fau/fd/FA00000875
- Subject Headings
- Soil pollution--Florida, Florida applesnail--Habitat, Florida applesnail--Effect of heavy metals on, Copper--Toxicology, Ecosystem management--Florida
- Format
- Document (PDF)
- Title
- The Role of Chemical Cues in Locating Pelagic Sargassum by the Associated Fish Stephanolepis hispidus.
- Creator
- Cox, Derek, Brooks, W. Randy, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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The ecosystem created by pelagic Sargassum is important in the life histories of a number of economically and ecologically important associated organisms. Fishes play a vital role in this food web and nutrient flow within these systems, but it is unknown how they locate these floating habitats. This study examined the role of natural chemical cues from Sargassum patches and the synthetic chemical Dimethylsulfonionpropionate (DMSP) for an associated fish, the planehead filefish (Stephanolepis...
Show moreThe ecosystem created by pelagic Sargassum is important in the life histories of a number of economically and ecologically important associated organisms. Fishes play a vital role in this food web and nutrient flow within these systems, but it is unknown how they locate these floating habitats. This study examined the role of natural chemical cues from Sargassum patches and the synthetic chemical Dimethylsulfonionpropionate (DMSP) for an associated fish, the planehead filefish (Stephanolepis hispidus) and a control fish species not associated with Sargassum, the masked goby (Coryphopterus personatus). Choice trials with a Y-maze apparatus determined that S. hispidus responded significantly to chemical cues from Sargassum while C. personatus did not. DMSP cues did not result in any significant behavioral responses for either fish. Demonstrating that S. hispidus can respond to chemical cues from Sargassum helps further our understanding of this unique floating algal reef and how fishes may locate it.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004684, http://purl.flvc.org/fau/fd/FA00004684
- Subject Headings
- Animal behavior, Habitat (Ecology), Marine algae, Marine chemical ecology, Predation (Biology), Sargassum -- Ecology
- Format
- Document (PDF)
