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- Title
- Aggressive Behaviors Of Adult Male Atlantic Spotted Dolphins (Stenella frontalis) During Intraspecific And Interspecific Aggressive Interactions.
- Creator
- Volker, Cassandra L., Herzing, Denise L., Hughes, Colin, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Atlantic spotted dolphins (Stenella frontalis) and bottlenose dolphins (Tursiops truncatus) are two sympatric species resident to the Bahamas. The visibility of the Bahamian water provided a unique opportunity to study spotted dolphin communication during aggression. This study’s main focus was to decipher any similarities or differences in the behaviors used by spotted dolphins during interspecific and intraspecific aggression. Both similarities and differences were discovered. Biting,...
Show moreAtlantic spotted dolphins (Stenella frontalis) and bottlenose dolphins (Tursiops truncatus) are two sympatric species resident to the Bahamas. The visibility of the Bahamian water provided a unique opportunity to study spotted dolphin communication during aggression. This study’s main focus was to decipher any similarities or differences in the behaviors used by spotted dolphins during interspecific and intraspecific aggression. Both similarities and differences were discovered. Biting, following, and chasing behavioral events were used more during interspecific aggression, while the display behavioral class was used more than the contact behavioral class during intrabut not interspecific aggression. This study showed that spotted dolphins use more energy intensive and risky behaviors when fighting interspecifically. This could result from having to fight and defend females from a larger species, trying to avoid sexual harassment from bottlenose males, or needing to use behaviors that are more overt and easily understood during interspecies communication.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004638, http://purl.flvc.org/fau/fd/FA00004638
- Subject Headings
- Atlantic spotted dolphin--Bahamas., Aggressive behavior in animals., Social behavior in animals., Aquatic mammals--Behavior., Predation (Biology), Predatory marine animals--Ecology.
- 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
- A comparison of body proportions in juvenile sea turtles: how shape may optimize survival in a vulnerable life stage.
- Creator
- Pate, Jessica Hope, Salmon, Michael, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Marine turtles produce many offspring which offsets the high mortality experienced by turtles during early development. Juvenile mortality might be reduced by evolving effective behavioral as well as morphological anti-predator defenses. Body proportions of three species (Caretta caretta, Chelonia mydas, Dermochelys coriacea) of turtles were measured in the first fourteen weeks of development to examine how growth may mitigate predation by gape-limited predators. Growth was categorized as...
Show moreMarine turtles produce many offspring which offsets the high mortality experienced by turtles during early development. Juvenile mortality might be reduced by evolving effective behavioral as well as morphological anti-predator defenses. Body proportions of three species (Caretta caretta, Chelonia mydas, Dermochelys coriacea) of turtles were measured in the first fourteen weeks of development to examine how growth may mitigate predation by gape-limited predators. Growth was categorized as isometric if shape did not change during development or allometric if body shape did change. All three species showed allometric growth in carapace width; however it was less pronounced in the larger D. coriacea turtles. Allometric growth in carapace width decreased as all three species grew in size. When high predation occurs in early development, many species will favor rapid growth into a size refuge. Juvenile sea turtles may optimize their survival by growing allometrically when predation risk is the greatest.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004223, http://purl.flvc.org/fau/fd/FA00004223
- Subject Headings
- Predation (Biology), Sea turtles -- Growth, Sea turtles -- Mortality, Sea turtles -- Population viability analysis
- Format
- Document (PDF)
- Title
- Diet variation and the consumptive effects of native centrarchids on benthic macroinvertebrates in wetlands.
- Creator
- Bransky, Jacob., Charles E. Schmidt College of Science, Center for Environmental Studies
- Abstract/Description
-
Fish predation can have structuring effects in aquatic communities, but the most important fish predators are not always immediately obvious. Generalist fish predators often occupy similar habitats and consume similar prey making determination of their consumptive impacts difficult. Understanding these consumptive impacts is important for understanding complex wetland food webs. I collected warmouth (Lepomis gulosus), bluespotted sunfish (Enneacanthus gloriosus), and dollar sunfish (Lepomis...
Show moreFish predation can have structuring effects in aquatic communities, but the most important fish predators are not always immediately obvious. Generalist fish predators often occupy similar habitats and consume similar prey making determination of their consumptive impacts difficult. Understanding these consumptive impacts is important for understanding complex wetland food webs. I collected warmouth (Lepomis gulosus), bluespotted sunfish (Enneacanthus gloriosus), and dollar sunfish (Lepomis marginatus) in two seasons from sloughs for both diet and bioenergetics analysis. Macroinvertebrates dominated diets of the three species, and nonparametric analyses revealed evidence of diet ontogeny in warmouth and potential competition for prey items among gape-matched individuals. Bioenergetics modeling revealed high levels of macroinvertebrate comsumption by these species relative to macroinvertebrate reproductive output suggesting that when combined with other sources of mortality, consumptive pressures placed by sunfish on benthic macroinvertebrates may be quite large.
Show less - Date Issued
- 2012
- PURL
- http://purl.flvc.org/FAU/3356894
- Subject Headings
- Wetland ecology, Predatory marine animals, Ecology, Predation (Biology), Habitat selction, Marine ecosystem management
- Format
- Document (PDF)
- Title
- Diet and foraging ecology of diamondback terrapins (Malaclemys Terrapin) in south Florida.
- Creator
- Denton, Mathew, Baldwin, John D., Florida Atlantic University, Charles E. Schmidt College of Science, Center for Environmental Studies
- Abstract/Description
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Dietary resource use for diamondback terrapins (Malaclemys terrapins) in subtropical mangrove habitats in south Florida creeks and islands was examined to elucidate long-term individual foraging strategies. Fecal analysis revealed seven categories of food items with gastropods, crabs, and bivalves being the most dominant food items respectively. Non-metric multidimensional scaling revealed differences in habitat, but not terrapin size class. Stable isotope analysis confirmed the findings,...
Show moreDietary resource use for diamondback terrapins (Malaclemys terrapins) in subtropical mangrove habitats in south Florida creeks and islands was examined to elucidate long-term individual foraging strategies. Fecal analysis revealed seven categories of food items with gastropods, crabs, and bivalves being the most dominant food items respectively. Non-metric multidimensional scaling revealed differences in habitat, but not terrapin size class. Stable isotope analysis confirmed the findings, identifying habitat and site differences in δ13C and δ15N values for both terrapins and their prey. Bi-plots of terrapin and potential prey δ 13C and δ 15N values revealed potential dietary sources previously undetermined by fecal analysis. Comparisons of scute and blood isotope data revealed significant differences in δ13C indicating potential shifts in either food resources and/or habitat use through the time period recorded in the scute tissue. These tissue comparisons represent a powerful tool for estimating long term foraging strategies for a key estuarine species.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004101
- Subject Headings
- Diamondback terrapin -- Habitat -- Florida., Diamondback terrapin -- Ecology -- Florida., Predation (Biology)
- Format
- Document (PDF)
- Title
- Foraging ecology of wading birds in a sub-tropical intertidal zone.
- Creator
- Calle, Leonardo, Gawlik, Dale E., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The first of five chapters describe the study area and study species, including a short description about the impetus for this research. The second chapter describes a unique hydrologic model for application in tidal ecosystems. The second chapter represents new information on the effects of various abiotic and biotic factors on foraging wading birds in this highly dynamic environment. The third chapter identifies important factors affecting the abundance of foraging wading birds in...
Show moreThe first of five chapters describe the study area and study species, including a short description about the impetus for this research. The second chapter describes a unique hydrologic model for application in tidal ecosystems. The second chapter represents new information on the effects of various abiotic and biotic factors on foraging wading birds in this highly dynamic environment. The third chapter identifies important factors affecting the abundance of foraging wading birds in intertidal environments. The fourth chapter presents a study of the foraging habitat preferences of two wading bird species in intertidal environments. The fifth chapter describes a conceptual model of wading bird foraging ecology and a predictive model of foraging habitat in intertidal zones. The conceptual model captures the major drivers and linkages between the abiotic and biotic variables thought to affect wading bird foraging abundance in intertidal habitats. The conceptual model also identifies major knowledge gaps in our understanding of foraging ecology of wading birds in coastal intertidal areas. The predictive model of foraging habitat is meant to be used by resource managers, but its framework may be useful for ecological studies in general. The final and sixth chapter provides a summary of all the major findings. Each chapter has been written so as to be independent of the other chapters. As such, a full background, along with a discussion of the relevance of the chapter's findings is provided for each chapter.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004087
- Subject Headings
- Habitat selection, Population biology, Predation (Biology), Water birds -- Geographical distribution, Water birds -- Habitat
- 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
- Effects of freshwater discharges and habitat architecture on oyster reef community development and diversity.
- Creator
- Salewski, Elizabeth a., Charles E. Schmidt College of Science, Center for Environmental Studies
- Abstract/Description
-
Oyster reefs support diverse estuarine communities and food webs. Factors controlling oyster reef community development were studied on restored reefs in the St. Lucie Estuary. Freshwater discharges create stresses that cause oyster mortality, habitat loss and reduction in reef community diversity. Using structural equation modeling, it was demonstrated that salinity, turbidity, and chlorophyll-a gradients influence oysters and some reef invertebrate species, but did not support the...
Show moreOyster reefs support diverse estuarine communities and food webs. Factors controlling oyster reef community development were studied on restored reefs in the St. Lucie Estuary. Freshwater discharges create stresses that cause oyster mortality, habitat loss and reduction in reef community diversity. Using structural equation modeling, it was demonstrated that salinity, turbidity, and chlorophyll-a gradients influence oysters and some reef invertebrate species, but did not support the predictions of the Intermediate Disturbance Hypothesis. In contrast, diversity and species richness were greatest at low stress sites. A field experiment showed that topographic relief and architectural complexity enhanced colonization and growth of reef-building species (e.g.oysters and mussels). The relief by complexity interaction had a higher order, synergistic effect on oyster abundance. When considered separately, increasing relief further enhanced dominant sessile taxa (cirripeds and ascideans) ; while, increasing complexity supported greater species richness and the abundance of cirripeds.
Show less - Date Issued
- 2012
- PURL
- http://purl.flvc.org/FAU/3355881
- Subject Headings
- American oyster, Reef ecology, Habitat conservation, Predation (Biology)
- Format
- Document (PDF)
- Title
- Fire ants on sea turtle nesting beaches in South Florida, USA, and ST. Croix, USVI.
- Creator
- Romais, Danielle K., Wetterer, James K., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The red imported fire ant, Solenopsis invicta, is a South American native introduced in Alabama in the early 20th century. This predatory species has rapidly spread throughout the southeastern US and parts of the West Indies, inflicting great ecological and economic damage. For example, Solenopsis invicta is known to attack the eggs and hatchlings of ground nesting birds and reptiles. The ants swarm into the nests attacking hatchlings and diminishing their chance for survival. My thesis...
Show moreThe red imported fire ant, Solenopsis invicta, is a South American native introduced in Alabama in the early 20th century. This predatory species has rapidly spread throughout the southeastern US and parts of the West Indies, inflicting great ecological and economic damage. For example, Solenopsis invicta is known to attack the eggs and hatchlings of ground nesting birds and reptiles. The ants swarm into the nests attacking hatchlings and diminishing their chance for survival. My thesis research aimed to survey the distribution of ants on sea turtle nesting beaches in South Florida and St. Croix, USVI, and to evaluate the possible threat of Solenopsis invicta and other predatory ants to sea turtle hatchlings.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fau/fd/FA0004052
- Subject Headings
- Biological invasions, Fire ants -- Venom -- Physiological effect, Predation (Biology), Sea turtles -- Florida -- Mortality, Sea turtles -- St. Croix -- Mortality, Wildlife conservation -- Florida, Wildlife conservation -- St. Croix
- Format
- Document (PDF)
- Title
- Effects of Cuban Treefrog (Osteopilus Septentrionalis) removal on native Florida hyla populations.
- Creator
- Cunningham, Miranda, Moore, Jon, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Invasive species are one of the major threats to biodiversity and understanding the effects any one invasive species has on members of its new ecosystem can help land managers decide how to best use their limited resources. This study attempted to show the effect Cuban Treefrogs (Osteopilus Septentrionalis) were having on native Florida hylids. For a year, Cuban Treefrogs were removed from three cypress domes and monitored in three other cypress domes, a change in the native population in the...
Show moreInvasive species are one of the major threats to biodiversity and understanding the effects any one invasive species has on members of its new ecosystem can help land managers decide how to best use their limited resources. This study attempted to show the effect Cuban Treefrogs (Osteopilus Septentrionalis) were having on native Florida hylids. For a year, Cuban Treefrogs were removed from three cypress domes and monitored in three other cypress domes, a change in the native population in the experimental domes was the eventual desired effect. Due to weather issues and low native hylid numbers no effect was shown, however due to environmental constraints an effect could not be ruled out either.
Show less - Date Issued
- 2015
- PURL
- http://purl.flvc.org/fau/fd/FA00004359, http://purl.flvc.org/fau/fd/FA00004359
- Subject Headings
- Conservation biology, Cuban Treefrog -- Florida, Hylidae, Predation (Biology), Wildlife management
- Format
- Document (PDF)
- Title
- Habitat selection among fishes and shrimp in the pelagic Sargassum community: the role of habitat architecture.
- Creator
- Bennice, Chelsea, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Pelagic Sargassum was used to determine the effects of habitat architecture for one species of shrimp (Leander tenuicornis) and two species of fish (Stephanolepis hispidus and Histrio histrio). Inter-thallus spacing (low, medium, and high) and depth (shallow versus deep) were manipulated independently to test whether the spatial components of habitat architecture. Two differing habitats (Sargassum versus seagrass species) were tested for the structural component of habitat architecture. There...
Show morePelagic Sargassum was used to determine the effects of habitat architecture for one species of shrimp (Leander tenuicornis) and two species of fish (Stephanolepis hispidus and Histrio histrio). Inter-thallus spacing (low, medium, and high) and depth (shallow versus deep) were manipulated independently to test whether the spatial components of habitat architecture. Two differing habitats (Sargassum versus seagrass species) were tested for the structural component of habitat architecture. There were no significant results for inter-thallus spacing experiments for L. tenuicornis and S. hispidus. H histrio selected habitats with medium inter-thallus spacing in two treatments. Large individual H. histrio contributed mostly to the significant effects. All three species selected habitats with a greater depth aspect. Finally, L. tenuicornis and H. histrio selected habitats with greater structural complexity (i.e., Sargassum). These results demonstrate clearly that habitat architecture of Sargassum influences habitat selection by these shrimp and fishes.
Show less - Date Issued
- 2012
- PURL
- http://purl.flvc.org/FAU/3358284
- Subject Headings
- Habitat (Ecology), Sargassum, Ecology, Animal behavior, Predation (Biology)
- Format
- Document (PDF)
- Title
- Nutrition and habitat driven foraging of wild dolphins in the Bahamas: a recipe for prey.
- Creator
- Malinowski, Christopher R., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Two sympatric dolphin species, Stenella frontalis and Tursiops truncatus, resident to Little Bahama Bank, Bahamas were found to mostly forage independent of one another, but occasionally foraged in mixed groups. Analysis of over 20 years of data revealed the degree of overlap to be minimal with spatially distinct regions identified for both species, environmental segregation based on depth, bottom type, temperature, and time of day. Results based on observational data indicated significant...
Show moreTwo sympatric dolphin species, Stenella frontalis and Tursiops truncatus, resident to Little Bahama Bank, Bahamas were found to mostly forage independent of one another, but occasionally foraged in mixed groups. Analysis of over 20 years of data revealed the degree of overlap to be minimal with spatially distinct regions identified for both species, environmental segregation based on depth, bottom type, temperature, and time of day. Results based on observational data indicated significant differences in group size and selected prey. For S. frontalis, lactating females had the most distinct diet, which differed from that of non-reproductively active (NRA) females. Pregnant females had ambiguous prey use results, but diet differences were revealed through nutritional analysis. Lactating females had a higher intake of all nutrients (% moisture, % lipid, % protein, and calories) than pregnant females but lower than NRA females. Mother and calf pairs selected prey for caloric and moisture values. The influence of calves on foraging groups was reflected through discrete differences in all nutrients. Males and females appeared to select the same major prey, but female prey use was much more diverse.
Show less - Date Issued
- 2011
- PURL
- http://purl.flvc.org/FAU/3318668
- Subject Headings
- Dolphins, Habitat, Predatory marine animals, Ecology, Marine ecosystem management, Predation (Biology), Aquatic mammals, Behavior
- Format
- Document (PDF)
- Title
- Physiological Effects of Disorientation in Loggerhead (Caretta caretta) and Green (Chelonia mydas) Sea Turtle Hatchlings.
- Creator
- Pankaew, Karen, Milton, Sarah L., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Following nest emergence, sea turtle hatchling dispersal can be disrupted by artificial light or skyglow from urban areas. Mis- or disorientation increases exposure to predation, thermal stress, and dehydration, could consume valuable energy, and thus influence the likelihood of survival. This study utilized laboratory simulations of extended crawl distances and field observations to investigate the energy cost of disorientation crawling on loggerhead (Caretta caretta) and green (Chelonia...
Show moreFollowing nest emergence, sea turtle hatchling dispersal can be disrupted by artificial light or skyglow from urban areas. Mis- or disorientation increases exposure to predation, thermal stress, and dehydration, could consume valuable energy, and thus influence the likelihood of survival. This study utilized laboratory simulations of extended crawl distances and field observations to investigate the energy cost of disorientation crawling on loggerhead (Caretta caretta) and green (Chelonia mydas) sea turtle hatchlings and the impact on the subsequent swim frenzy. Extended crawls increased oxygen consumption, decreased plasma glucose, and reduced green hatchling swim performance following a 200m crawl. Surprisingly, plasma lactate concentrations did not increase with crawl distance, likely due to frequent rest periods that would, however, increase time on the beach and thus exposure to predators. This research may provide managers with physiological data to determine best practices for sea turtle conservation and adds to the biological knowledge of these animals.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004619
- Subject Headings
- Predation (Biology), Sea turtles--Life cycles., Sea turtles--Nests--Protection., Wildlife conservation., Exterior lighting--Environmental aspects.
- Format
- Document (PDF)
- Title
- Predatory Impacts of Crayfish on Apple Snails (Pomacea paludosa and P. maculata).
- Creator
- Davidson, Andrew, Dorn, Nathan, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Theory predicts that when prey can reach a size refuge from predation, prey vulnerability to predation is a function of hatchling size, growth rate, and the handling limitations of its predator, which collectively influence the amount of time prey spend vulnerable. I examined the mechanistic role of prey size for the predator-prey interaction between predatory crayfish (Procambarus fallax) and apple snail prey (Pomacea paludosa and P. maculata) and found that crayfish feeding rates decreased...
Show moreTheory predicts that when prey can reach a size refuge from predation, prey vulnerability to predation is a function of hatchling size, growth rate, and the handling limitations of its predator, which collectively influence the amount of time prey spend vulnerable. I examined the mechanistic role of prey size for the predator-prey interaction between predatory crayfish (Procambarus fallax) and apple snail prey (Pomacea paludosa and P. maculata) and found that crayfish feeding rates decreased with snail size, such that smaller hatchling P. maculata were more than twenty times more vulnerable than hatchling P. paludosa. Experimental manipulations of productivity increased apple snail growth rates, reducing the effects of predatory crayfish on P. maculata survivorship, but not P. paludosa survivorship. My results indicate that when prey can reach a size refuge from predation, increased system productivity decreases predator limitation of that prey.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004760, http://purl.flvc.org/fau/fd/FA00004760
- Subject Headings
- Predation (Biology), Gastropoda--Physiology., Florida applesnail--Habitat., Florida applesnail--Environmental aspects.
- Format
- Document (PDF)
- Title
- The distribution of predaceous fire ant species on important sea turtle nesting beaches in St. Croix, U.S. Virgin Islands.
- Creator
- Balkaran, Kavita, Wetterer, James K., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The tropical fire ant, Solenopsis geminata is a New World species with a wide native range including South America as well as several Caribbean islands. The red imported fire ant, Solenopsis invicta is native to parts of South America. Both species are known for preying on sea turtles’ eggs and hatchlings. The objectives of this thesis research were to conduct follow-up and baseline ant species distribution surveys on four sea turtle nesting beaches in St. Croix, U. S. Virgin Islands. Tuna...
Show moreThe tropical fire ant, Solenopsis geminata is a New World species with a wide native range including South America as well as several Caribbean islands. The red imported fire ant, Solenopsis invicta is native to parts of South America. Both species are known for preying on sea turtles’ eggs and hatchlings. The objectives of this thesis research were to conduct follow-up and baseline ant species distribution surveys on four sea turtle nesting beaches in St. Croix, U. S. Virgin Islands. Tuna baits were set out at beaches; specimens were collected, frozen, preserved then identified. Results show that there was a significant change in the fire ants’ distribution at Sandy Point National Wildlife Refuge (SPNWR) while none were found at Jack Bay. Fire ants were also present on the other two baseline surveyed nesting beaches. The displacement of S. geminata by S. invicta was observed at SPNWR, which also was presumed by previous surveys.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004077, http://purl.flvc.org/fau/fd/FA00004077
- Subject Headings
- Biological invasions, Fire ants -- St. Croix -- Sandy Point National Wildlife Refuge (United States Virgin Islands) -- Geographical distribution, Predation (Biology), Sandy Point National Wildlife Refuge (United States Virgin Islands), Sea turtles -- Nests -- St. Croix -- Sandy Point National Wildlife Refuge (United States Virgin Islands)
- Format
- Document (PDF)
- Title
- The role of air and waterborne odors in orientation and food detection in three species of marine turtles.
- Creator
- Kedzuf, Stephanie C., Salmon, Michael, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The cues used by marine turtles to locate foraging areas in the open ocean are largely unknown though some species (especially the green turtle [Chelonia mydas], the loggerhead [Caretta caretta], and the leatherback [Dermochelys coriacea]) somehow locate areas of high productivity. Loggerheads can detect airborne odors, but a capacity to orient has not yet been investigated. In this comparative study, tethered loggerheads and leatherbacks were exposed to dimethyl sulfide (DMS) or food odors...
Show moreThe cues used by marine turtles to locate foraging areas in the open ocean are largely unknown though some species (especially the green turtle [Chelonia mydas], the loggerhead [Caretta caretta], and the leatherback [Dermochelys coriacea]) somehow locate areas of high productivity. Loggerheads can detect airborne odors, but a capacity to orient has not yet been investigated. In this comparative study, tethered loggerheads and leatherbacks were exposed to dimethyl sulfide (DMS) or food odors in a laminar flow of air. Turtles did not orient into the air current. Free-swimming loggerheads and green turtles were also exposed to air- or waterborne food (squid) odor plus a neutral visual stimulus. Both species showed increases in swimming activity and biting behavior to both stimuli. These results suggest that airborne odors are likely not used to locate distant areas, but that they are used in localized food searching efforts.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004296
- Subject Headings
- Animal behavior, Animal orientation, Population genetics, Predation (Biology), Sea turtles -- Habitat, Sea turtles -- Life cycles, Wildlife conservation
- Format
- Document (PDF)
- Title
- Wading Bird Reproductive and Physiological Responses to Environmental Disturbance in a Managed Lake Ecosystem.
- Creator
- Chastant, Jennifer E., Gawlik, Dale E., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Wetlands are some of the most diverse and productive ecosystems on earth. Water-level fluctuations determine the ecological function of shallow lakes and wetlands. Currently, anthropogenic modification to water-level fluctuations is the leading source of ecological degradation in lake and wetland ecosystems worldwide. I used wading birds nesting in Lake Okeechobee, as a model system to address the challenges of environmental restoration within an ecosystem greatly impacted by anthropogenic...
Show moreWetlands are some of the most diverse and productive ecosystems on earth. Water-level fluctuations determine the ecological function of shallow lakes and wetlands. Currently, anthropogenic modification to water-level fluctuations is the leading source of ecological degradation in lake and wetland ecosystems worldwide. I used wading birds nesting in Lake Okeechobee, as a model system to address the challenges of environmental restoration within an ecosystem greatly impacted by anthropogenic activities. Specifically, I 1) identified environmental factors most important for predicting the number of wading bird nests, 2) tested the assumptions of both the match-mismatch and the threshold hypothesis by modeling the relationship between nesting success and prey density with foraging habitat availability, and 3) measured the stress response of Great (Ardea alba) and Snowy Egrets (Egretta thula) to hydrologically-mediated changes in food availability. Collectively, the results suggest that the number of nests was greatest when area of nesting substrate was high and water-levels were moderate (3.9 - 4.4 m). Nest numbers dropped when either nesting substrate or foraging habitat was limited. My investigation into the predictions of the match-mismatch and threshold hypotheses found that indeed, prey density can reduce or intensify the effects of a mismatch event. The interaction of prey density and foraging habitat availability was significant and positive in both models. Saturation thresholds existed for both fledging success (147 prey (m^2)^-1) and total productivity (189 prey (m^2)^-1), above which high concentrations of prey could sustain nesting when foraging habitat availability was low. Finally, my studies of the stress response support the hypothesis that hydrologic factors associated with prey availability play an important role in regulating nesting patterns, although the level of food limitation the birds experience at the lake was not as severe as expected. Model selection identified foraging habitat availability as most influential to the nestling Great Egret stress response, whereas foraging habitat availability and prey density both influenced nestling Snowy Egret stress response. Moreover, the Snowy Egret stress response was more sensitive to changes in prey availability than was the Great Egret stress response. Temperature and foraging conditions influenced yolk corticosterone concentrations for both egret species.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004779
- Subject Headings
- Wetland ecology., Estuarine ecology., Water birds--Habitat., Predation (Biology)
- Format
- Document (PDF)
- Title
- Wading bird prey production and prey selection in a dynamic wetland.
- Creator
- Klassen, Jessica A., Gawlik, Dale E., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Anthropogenic impacts, such as habitat destruction and spread of exotic species, are contributing to the sixth major extinction event in Earth’s history. To develop effective management and conservation plans, it is important to understand the ecological drivers of at-risk populations, assess the ability of a population to adapt to environmental change, and develop research methods for long-term ecosystem monitoring. I used wading birds nesting in the Florida Everglades, USA as a model system...
Show moreAnthropogenic impacts, such as habitat destruction and spread of exotic species, are contributing to the sixth major extinction event in Earth’s history. To develop effective management and conservation plans, it is important to understand the ecological drivers of at-risk populations, assess the ability of a population to adapt to environmental change, and develop research methods for long-term ecosystem monitoring. I used wading birds nesting in the Florida Everglades, USA as a model system to address the challenges of managing and monitoring populations within an ecosystem greatly impacted by anthropogenic activities. Specifically, my project investigated 1) the prey selection of wading bird species, and the role of prey and foraging habitat availability on annual nesting numbers, 2) the ability of using diet change to predict species adaptability to a rapidly changing environment, and 3) the use of sensory data to provide low-cost, long-term monitoring of dynamic wetlands. I found that tricolored herons, snowy egrets, and little blue herons consumed marsh fish larger than those generally available across the landscape. Additionally, number of nests initiated by tricolored herons, snowy egrets, and little blue herons was strongly correlated with the annual densities of large fish available within the Everglades landscape. Conversely, number of nests initiated by wood storks, great egrets, and white ibises was more correlated with the amount of foraging habitat availability across the nesting season. Wood stork diets changed considerably since the 1960’s, consisting of mainly sunfish and exotic fish as opposed to marsh fishes dominant in historical diet studies. Storks also consumed more exotic fish species than they did historically. This diet plasticity and the species’ ability to exploit anthropogenic habitats may be conducive to maintaining population viability as storks experience widespread human-induced changes to their habitat. Sensory-only data models generated complementary results to models that used site-specific field data. Additionally, sensory-only models were able to detect different responses between size classes of fish to the processes that increase their concentrations in drying pools. However, the degree to which sensory variables were able to fit species data was dependent upon the ability of sensors to measure species-specific population drivers and the scale at which sensors can measure environmental change.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004716
- Subject Headings
- Charadriiformes -- Habitat -- Florida -- Everglades, Ciconiiformes -- Habitat -- Florida -- Everglades, Everglades National Park (Fla.) -- Environmental conditions, Predation (Biology), Wetland ecology, Wildlife conservation
- Format
- Document (PDF)
- Title
- A retrospective analysis of sea turtle nest depredation patterns at Canaveral National Seashore, Florida.
- Creator
- Welicky, Rachel., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Nest predation can significantly reduce hatchling recruitment in sea turtle populations. This study uses 20 years of data from Canaveral National Seashore, Florida, which has pristine and altered beaches. Chi-square tests were used to determine if secondary predation events were related to the nest's primary depredation event. To determine if human beach use and nest predation are spatially or temporally linked, we ranked human beach use and examined predation frequency across all screened...
Show moreNest predation can significantly reduce hatchling recruitment in sea turtle populations. This study uses 20 years of data from Canaveral National Seashore, Florida, which has pristine and altered beaches. Chi-square tests were used to determine if secondary predation events were related to the nest's primary depredation event. To determine if human beach use and nest predation are spatially or temporally linked, we ranked human beach use and examined predation frequency across all screened and marked nests (n=40,441). Lastly, I quantified nest predation risk spatially and temporally. I found that primary predation increases the chance of a nest suffering subsequent predation. Primary and multiple predation events occurred with greater frequency in limited use areas and with lowest frequency in moderate use areas. Predation risk decreased by an average of 29.5% from 2000-2008. Nests deposited midseason were 9.8% more likely to be predated than nests deposited early or late.
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/2683130
- Subject Headings
- Predation (Biology), Wildlife managment, Sea turtles, Sea turtles, Nests
- 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)