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- 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
-
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
-
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
- TROPHIC INTERACTIONS OF OCTOPUS VULGARIS AND THE IMPACTS OF PLASTIC LEACHATE OLEAMIDE.
- Creator
- Hair, Madelyn A., McCoy , Michael, Florida Atlantic University, Department of Marine Science and Oceanography, Charles E. Schmidt College of Science
- Abstract/Description
-
Octopus predation and species selection contribute to community structure in benthic habitats, where plastic pollution accumulates. This study investigated how the bioactive plastic additive oleamide alters trophic interactions and behaviors of the common octopus (Octopus vulgaris) and its prey. We quantified activity budgets and trophic interactions for octopuses and multiple prey types (hermit crabs, free-living crabs, bivalves, and gastropods) before and after exposure to oleamide. Our...
Show moreOctopus predation and species selection contribute to community structure in benthic habitats, where plastic pollution accumulates. This study investigated how the bioactive plastic additive oleamide alters trophic interactions and behaviors of the common octopus (Octopus vulgaris) and its prey. We quantified activity budgets and trophic interactions for octopuses and multiple prey types (hermit crabs, free-living crabs, bivalves, and gastropods) before and after exposure to oleamide. Our analysis suggested that some taxa (octopuses and hermit crabs) exhibit more active behaviors during oleamide exposure. Free living crabs responded primarily to the threat of octopus predation, while other taxa did not show clear behavioral responses. Exposure to oleamide increased trophic interactions and the probability of mobile prey taxa being observed on the same side of the aquarium as the octopus, thus increasing the opportunity for predation. Our results support previous research showing that plastic leachates can impair decision-making, making prey more susceptible to predation.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014278
- Subject Headings
- Common octopus, Predation (Biology), Plastics--Environmental aspects
- Format
- Document (PDF)
- Title
- The role of prey detection in the selection of prey by pinfish Lagodon rhomboides (Linnaeus).
- Creator
- Luczkovich, Joseph J., Harbor Branch Oceanographic Institute
- Date Issued
- 1988
- PURL
- http://purl.flvc.org/FCLA/DT/3353818
- Subject Headings
- Lagodon rhomboides, Pinfish, Predator & prey, Predation (Biology)
- Format
- Document (PDF)
- Title
- The role of predationby decapod crustaceans in seagrass ecosystems.
- Creator
- Nelson, Walter G., Harbor Branch Oceanographic Institute
- Date Issued
- 1981
- PURL
- http://purl.flvc.org/fau/fd/FA00007090
- Subject Headings
- Seagrasses--Florida--Indian River (Lagoon), Seagrasses--Ecology, Ecosystems, Decapoda (Crustacea), Predation (Biology)
- 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
-
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)
- 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
- THE ROLE OF ACETYLCHOLINE IN FELINE PREDATORY ATTACK: QUANTITATIVE AND BEHAVIORAL ANALYSES.
- Creator
- SERVIDIO, SUSAN., Florida Atlantic University
- Abstract/Description
-
The role of acetylcholine in feline predatory attack was examined by pharmacological manipulations. Attack behavior was partitioned into components of app roach (visualorientation, approach, extension of the head, trapping, seizing in the jaws, biting) and withdrawal (whole body withdrawal, retraction of the head and upper torso, swiping ) in an attempt to selectively affect specific components of the attack pattern. Carbachol, a cholinomimetic, produced an increase in the percentage of head...
Show moreThe role of acetylcholine in feline predatory attack was examined by pharmacological manipulations. Attack behavior was partitioned into components of app roach (visualorientation, approach, extension of the head, trapping, seizing in the jaws, biting) and withdrawal (whole body withdrawal, retraction of the head and upper torso, swiping ) in an attempt to selectively affect specific components of the attack pattern. Carbachol, a cholinomimetic, produced an increase in the percentage of head and upper torso retractions, as well as a slight inhibition of prey seizing. Atropine methyl nitrate, an anticholinergic, was found to decrease the percentage of head and upper torso retractions, as well as the rate of swiping. The primary effect of atropine, however, was a slight, non-specific inhibition of all behaviors, as evidenced by longer latencies to kill the prey, as well as by long periods of pausing and dry mouth symptoms. Leakage of the drug into the periphery may have contributed to these effects.
Show less - Date Issued
- 1981
- PURL
- http://purl.flvc.org/fcla/dt/14047
- Subject Headings
- Predation (Biology), Acetylcholine
- Format
- Document (PDF)
- Title
- The influence of prey identity and size on selection of prey by two marine fishes.
- Creator
- Main, Kevan L., Harbor Branch Oceanographic Institute
- Date Issued
- 1985
- PURL
- http://purl.flvc.org/FCLA/DT/3353752
- Subject Headings
- Predators, Marine fishes, Lagodon rhomboides, Syngnathus floridae, Shrimps, Predation (Biology)
- Format
- Document (PDF)
- Title
- The influence of predatory decapods, refuge, and microhabitat selection on seagrass communities.
- Creator
- Leber, Kenneth M., Harbor Branch Oceanographic Institute
- Date Issued
- 1985
- PURL
- http://purl.flvc.org/FCLA/DT/3172808
- Subject Headings
- Shrimps, Seagrasses --Mexico, Gulf of --Identification, Seagrasses –Ecology, Thalassia, Decapoda (Crustacea), Predation (Biology)
- Format
- Document (PDF)
- Title
- The importance of predation by crabs and fishes on benthic infauna in Chesapeake Bay.
- Creator
- Virnstein, Robert W., Harbor Branch Oceanographic Institute
- Date Issued
- 1977
- PURL
- http://purl.flvc.org/FCLA/DT/3174984
- Subject Headings
- Predation (Biology), Predatory animals--Ecology, Benthic animals, Chesapeake Bay (Md. and Va.), Estuaries
- Format
- Document (PDF)
- Title
- The hawksbill rookery at Antigua, W.I.: nest success, hatchling behavior, and hatchling survival during offshore migration.
- Creator
- Reising, Megan, Salmon, Michael, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The younger life history stages of marine turtles (eggs, hatchlings) often fail to survive. To compensate, sea turtles nest several times/season and produce large clutches of eggs. The hawksbill produces the largest clutches (150 eggs) and the smallest hatchlings of any marine turtle. My study, done at Jumby Bay in Antigua, West Indies, was designed to determine whether they did so to compensate for loss in the nest, hatchling loss in the water, or both factors. I found that most of the eggs ...
Show moreThe younger life history stages of marine turtles (eggs, hatchlings) often fail to survive. To compensate, sea turtles nest several times/season and produce large clutches of eggs. The hawksbill produces the largest clutches (150 eggs) and the smallest hatchlings of any marine turtle. My study, done at Jumby Bay in Antigua, West Indies, was designed to determine whether they did so to compensate for loss in the nest, hatchling loss in the water, or both factors. I found that most of the eggs (79 %) survived to become hatchlings that left the nest and entered the sea. However, 88 % of the hatchlings swimming offshore were taken by predators within minutes after they began their migration. These results suggest that at Jumby Bay, large clutch size is favored in hawksbills because of predation pressures on the hatchlings.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fau/fd/FA0004049
- Subject Headings
- Animal migration -- Antigua -- Jumbo Bay, Animal orientation -- Antigua -- Jumbo Bay, Hawksbill turtle -- Research -- Antigua -- Jumbo Bay, Predation (Biology), Sea turtles -- Research -- Antigua -- Jumbo Bay, Wildlife conservation -- Antigua -- Jumbo Bay
- Format
- Document (PDF)
- Title
- The feeding and growth of the sea nettle, Chrysaora quinquecirrha (Desor), in the laboratory.
- Creator
- Larson, R. J., Harbor Branch Oceanographic Institute
- Date Issued
- 1986
- PURL
- http://purl.flvc.org/FCLA/DT/3174015
- Subject Headings
- Jellyfishes, Predation (Biology), Animal feeding, Ctenophora, Gastrodes (Ctenophora)
- Format
- Document (PDF)
- Title
- The effects of prey size, predator size, and sediment composition on the rate of predation of the blue crab, Callinectes Sapidus Rathbun, on the hard clam, Mercenaria Mercenaria (Linne).
- Creator
- Arnold, William S., Harbor Branch Oceanographic Institute
- Date Issued
- 1984
- PURL
- http://purl.flvc.org/FCLA/DT/3331860
- Subject Headings
- Blue crab, Callinectes, Predation (Biology), Mercenaria mercenaria
- 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
- A test of factors affecting the foraging success of scarlet ibis.
- Creator
- Stanek, Rebecca A., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Wading bird foraging success is influenced by many different factors. From January to March 2008, I conducted a small-scale experiment with three captive Scarlet Ibis (Eudocimus ruber) at the Palm Beach Zoo, in West Palm Beach, Florida. Prey density and the presence of conspecifics were manipulated to test for a response by ibis in terms of prey capture rate. Mixed model analysis, when one prey type was available, showed that capture rate increased significantly with prey density and...
Show moreWading bird foraging success is influenced by many different factors. From January to March 2008, I conducted a small-scale experiment with three captive Scarlet Ibis (Eudocimus ruber) at the Palm Beach Zoo, in West Palm Beach, Florida. Prey density and the presence of conspecifics were manipulated to test for a response by ibis in terms of prey capture rate. Mixed model analysis, when one prey type was available, showed that capture rate increased significantly with prey density and decreased with the presence of conspecifics. When two prey types were available, prey density and the presence of conspecifics had no effect on the capture rates of either prey type. Selectivity analysis revealed that ibis always selected for crayfish in mixed treatments. I hypothesize that the number of prey types available in a treatment played an important role in determining how fish density and the presence of conspecifics affected ibis foraging success.
Show less - Date Issued
- 2009
- PURL
- http://purl.flvc.org/FAU/215288
- Subject Headings
- Scarlet ibis, Food, Birds, Ecology, Birds, Behavior, Wildlife management, Predation (Biology)
- Format
- Document (PDF)
- Title
- Species densities of macrobenthos associated with seagrass: a field experimental study of predation.
- Creator
- Young, David K., Buzas, M. A., Young, Martha W., Harbor Branch Oceanographic Institute
- Date Issued
- 1976
- PURL
- http://purl.flvc.org/FCLA/DT/3352181
- Subject Headings
- Seagrasses--Florida--Indian River (Lagoon), Predation (Biology), Seagrasses--Ecology, Food webs, Species
- Format
- Document (PDF)
- Title
- Solitary ascidians as predators of invertebrate larvae: evidence from gut analyses and plankton samples.
- Creator
- Bingham, Brian L., Walters, L. J., Harbor Branch Oceanographic Institute
- Date Issued
- 1989
- PURL
- http://purl.flvc.org/FCLA/DT/3353840
- Subject Headings
- Sea squirts, Ascidians, Invertebrates--Larvae, Predation (Biology), Marine invertebrates--Ecology
- Format
- Document (PDF)
- Title
- Snapping shrimp protect host anemones from predators.
- Creator
- McCammon, Amber., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The sea anemone Bartholomea annulata, is an ecologically important member of Caribbean coral reefs. This anemone serves as symbiotic host to crustacean associates, some of which may control parasite loads by "cleaning" reef fishes. Associates may gain protection from predation by dwelling with anemones. B. annulata was the most abundant anemone documented on three reefs, with 52% host to crustacean symbionts. Of those occupied by multi-species groups, 92% included Alpheus armatus shrimp. A....
Show moreThe sea anemone Bartholomea annulata, is an ecologically important member of Caribbean coral reefs. This anemone serves as symbiotic host to crustacean associates, some of which may control parasite loads by "cleaning" reef fishes. Associates may gain protection from predation by dwelling with anemones. B. annulata was the most abundant anemone documented on three reefs, with 52% host to crustacean symbionts. Of those occupied by multi-species groups, 92% included Alpheus armatus shrimp. A. armatus is an important anemone associate providing protection to the anemone from predators such as Hermodice carunculata, in laboratory and field trials. H. carunculata can completely devour or severely damage prey anemones. Here I show that anemones hosting symbiotic alpheid shrimp are extremely less likely to sustain damage by predators than solitary anemones. The role of protector may be reciprocally provided by anemone and decapod associates.
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/1930494
- Subject Headings
- Predation (Biology), Animal behavior, Coral reef ecology, Sea anemones, Marine ecology
- 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)