View All Items

Title: Entrainment of larval release in an intertidal crab ( Uca thayeri) after exposure to a different tidal regime: Testing the "plasticity" hypothesis.
Creator: Weaver, Ann, Florida Atlantic University, Salmon, Michael
Abstract/Description: Endogenous rhythms allow most organisms to synchronize their behavior and physiology with physical cycles that vary on a daily, lunar or annual cycle. Populations within species often show variation in the timing of functionally identical rhythms. This variation occurs because physical cycles may differ with geography. The purpose of this study was to determine whether hatching rhythms shown by fiddler crabs (Genus Uca) on one coastline could be entrained by the different tide patterns...
Show moreEndogenous rhythms allow most organisms to synchronize their behavior and physiology with physical cycles that vary on a daily, lunar or annual cycle. Populations within species often show variation in the timing of functionally identical rhythms. This variation occurs because physical cycles may differ with geography. The purpose of this study was to determine whether hatching rhythms shown by fiddler crabs (Genus Uca) on one coastline could be entrained by the different tide patterns present at another coastline. To test this I transferred breeding females (Uca thayeri) from mangroves on the west coast of Florida to mangroves on the east coast. On the west coast, females are exposed to "mixed" tides; most release their larvae during the day or night (early summer), or during the day (mid- to late summer). On the east coast, females are exposed to "semidiurnal" tides; they release their larvae between dusk and midnight. After four weeks of exposure to the East Coast tides, crabs from the West Coast showed hatching rhythms identical to the resident crabs. This change indicates that the crabs show behavioral (phenotypic) "plasticity". These observations provide further evidence for the adaptive value of behavioral plasticity.
Show less
Date Issued: 2000
PURL: http://purl.flvc.org/fcla/dt/15774
Subject Headings: Fiddler crabs--Eggs, Fiddler crabs--Adaptation, Biological rhythms
Format: Document (PDF)

Title: Larval release by the fiddler crab Uca thayeri: Timing and cues used under different tidal regimes.
Creator: Kellmeyer, Kay, Florida Atlantic University, Salmon, Michael, Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description: Hatching rhythms of intertidal crabs vary in timing with species, burrow position, tidal regimes and larval vulnerability. Most fiddler crabs time larval release with the nocturnal high fide. This is possible in semidiurnal tidal regimes because there are nocturnal high tides each lunar day. However, mixed tidal regimes have a semidiurnal and a diurnal period. During the diurnal phase high fide occurs in the afternoon. This variation in tidal inundation patterns may influence the timing of...
Show moreHatching rhythms of intertidal crabs vary in timing with species, burrow position, tidal regimes and larval vulnerability. Most fiddler crabs time larval release with the nocturnal high fide. This is possible in semidiurnal tidal regimes because there are nocturnal high tides each lunar day. However, mixed tidal regimes have a semidiurnal and a diurnal period. During the diurnal phase high fide occurs in the afternoon. This variation in tidal inundation patterns may influence the timing of larval release. Comparisons between two populations of fiddler crab (Uca thayeri ), exposed to different tidal regimes, indicated they time larval release differently. The population exposed to semidiurnal tides timed larval release with the nocturnal high tide prior to the maximum amplitude tide. The population exposed to mixed tides timed larval release with the diurnal maximum amplitude tide. The differences between the populations can be related to their ecology but other variables may contribute.
Show less
Date Issued: 1999
PURL: http://purl.flvc.org/fcla/dt/15732
Subject Headings: Crabs--Reproduction, Fiddler crabs
Format: Document (PDF)

Title: Comparative studies of retinal design among sea turtles: Histological and behavioral correlates of the visual streak.
Creator: DeCarlo, Lisa Joy., Florida Atlantic University, Salmon, Michael, Wyneken, Jeanette
Abstract/Description: We understand very little about the relationships between eye anatomy and visual ecology in sea turtles. Sea turtles use visual information in important contexts, such as selecting habitats, detecting predators, or locating mates or food. This study represents an effort to clarify the form/function relationship between retinal morphology and the behavioral ecology of sea turtle hatchlings. Thus, it is an important first step in relating sea turtle eye anatomy with visual ecology and relating...
Show moreWe understand very little about the relationships between eye anatomy and visual ecology in sea turtles. Sea turtles use visual information in important contexts, such as selecting habitats, detecting predators, or locating mates or food. This study represents an effort to clarify the form/function relationship between retinal morphology and the behavioral ecology of sea turtle hatchlings. Thus, it is an important first step in relating sea turtle eye anatomy with visual ecology and relating the two to sea turtle natural history. Some organisms possess retinas that contain morphologically specialized cellular areas. The "visual streak," is one such area; receptor cells and associated interneurons are concentrated in a horizontal band in the retina. Three species of sea turtles (Chelonia mydas, Caretta caretta, and Dermochelys coriacea) possess a visual streak located along the horizontal mid-line of the retina, although they differed in streak development. The differences in streak development can be related to their ecology.
Show less
Date Issued: 1998
PURL: http://purl.flvc.org/fcla/dt/15548
Subject Headings: Sea turtles, Eye--Anatomy, Vision
Format: Document (PDF)

Title: The use of wire cages to protect sea turtle nests: Are there better alternatives?.
Creator: Mroziak, Melissa Lynn, Florida Atlantic University, Salmon, Michael
Abstract/Description: The beaches of Boca Raton, Florida serve as a rookery site for three species of sea turtles, all of whom are considered either federally threatened (loggerhead) or endangered (green turtle, leatherback). At this beach, nest security was though to be compromised by both human visitors and increasing mammalian predators populations. Since 1988, the City has employed the use of square wire cages to protect the nests from both factors. Cage effectiveness was questioned due to high predation rates...
Show moreThe beaches of Boca Raton, Florida serve as a rookery site for three species of sea turtles, all of whom are considered either federally threatened (loggerhead) or endangered (green turtle, leatherback). At this beach, nest security was though to be compromised by both human visitors and increasing mammalian predators populations. Since 1988, the City has employed the use of square wire cages to protect the nests from both factors. Cage effectiveness was questioned due to high predation rates, despite caging. Evaluations to determine the effectiveness of this method were conducted. Pairs of caged (control) and uncaged (experimental) nests were established in zones reflecting high/low traffic and high/low predator attacks and monitored on a daily basis. Following emergence, nest fate comparisons were made. Decoy cages were used to determine predator efficiency. Data suggest that cages are not needed in areas of low traffic or predator attacks. Additional data suggest that cages actually attract, rather than deter, mammalian predators.
Show less
Date Issued: 1997
PURL: http://purl.flvc.org/fcla/dt/15441
Subject Headings: Sea turtles--Florida, Sea turtles--Nests--Florida
Format: Document (PDF)

Title: Nest caging as a sea turtle management strategy: Do the benefits outweigh the costs on urban beaches?.
Creator: Adamany, Stephanie Lynne., Florida Atlantic University, Salmon, Michael
Abstract/Description: Caging of sea turtle nests has used by City of Boca Raton's sea turtle conservation program to deter terrestrial predators and reduce human disturbance. The juxtaposition of nest cages and artificial lighting may pose serious threats to hatchlings. I addressed possible negative effects of cages on sea turtle hatchlings' seafinding abilities and potential "cage-trapping" under natural and artificially illuminated conditions. Cages did not effect hatchling orientation on artificially...
Show moreCaging of sea turtle nests has used by City of Boca Raton's sea turtle conservation program to deter terrestrial predators and reduce human disturbance. The juxtaposition of nest cages and artificial lighting may pose serious threats to hatchlings. I addressed possible negative effects of cages on sea turtle hatchlings' seafinding abilities and potential "cage-trapping" under natural and artificially illuminated conditions. Cages did not effect hatchling orientation on artificially illuminated or dark beaches. Hatchlings did not experience any delay in cage escape on dark beaches, but a significant number were trapped inside the cages on artificially illuminated beaches. The highest incidence of trapping occurred on nights surrounding a new moon. Disoriented hatchlings exited cages either after city lighting was reduced (past midnight) or as natural levels of illumination increased shortly before sunrise. When cages were darkened all turtles escaped but many still exhibited signs of disorientation.
Show less
Date Issued: 1996
PURL: http://purl.flvc.org/fcla/dt/15312
Subject Headings: Sea turtles--Florida, Sea turtles--Nests
Format: Document (PDF)

Title: The effects of beach renourishment on the nesting behavior and hatching success of the loggerhead sea turtle on Jupiter Island, Florida: A seven year study.
Creator: Steinitz, Mary Julie., Florida Atlantic University, Salmon, Michael
Abstract/Description: Jupiter Island is a barrier Island on the central East Coast of Florida whose beaches are subject to severe erosion. At intervals of several years, lost sand is replaced by the addition of sand ("renourishment") from other locations. In this study, I determined the effect of sand replacement on sea turtle nesting activity, and on the survival of nests placed on renourished and an adjacent natural beach. Renourishment caused a reduction in nesting activity by the turtles, which lasted about...
Show moreJupiter Island is a barrier Island on the central East Coast of Florida whose beaches are subject to severe erosion. At intervals of several years, lost sand is replaced by the addition of sand ("renourishment") from other locations. In this study, I determined the effect of sand replacement on sea turtle nesting activity, and on the survival of nests placed on renourished and an adjacent natural beach. Renourishment caused a reduction in nesting activity by the turtles, which lasted about two years. Thereafter, turtle nesting on renourished and control beaches was similar. There were no differences in nest survival between the two sites. Renourishment prevents the loss of beach and shoreline property, but is not necessarily beneficial to sea turtles.
Show less
Date Issued: 1996
PURL: http://purl.flvc.org/fcla/dt/15292
Subject Headings: Loggerhead turtle, Sea turtles--Florida--Jupiter Island, Beach nourishment
Format: Document (PDF)

Title: The magnetic compass of the loggerhead sea turtle (Caretta caretta L.): Can surface waves establish magnetic directional preference?.
Creator: Goff, Matthew Douglas, Florida Atlantic University, Salmon, Michael
Abstract/Description: Hatchling loggerhead sea turtles emerge from their nests on oceanic beaches, crawl to the surf zone, and swim out to sea. How do turtles maintain oriented headings once they lose contact with land? I tested the hypothesis that by swimming into surface waves hatchlings establish an offshore heading (directional preference), and that once out to sea this heading is transferred to, and maintained by, a magnetic compass. This hypothesis was supported by laboratory and field experiments, described...
Show moreHatchling loggerhead sea turtles emerge from their nests on oceanic beaches, crawl to the surf zone, and swim out to sea. How do turtles maintain oriented headings once they lose contact with land? I tested the hypothesis that by swimming into surface waves hatchlings establish an offshore heading (directional preference), and that once out to sea this heading is transferred to, and maintained by, a magnetic compass. This hypothesis was supported by laboratory and field experiments, described herein. A directional preference can also be established by oriented crawling (from the nest to the surf zone). Thus hatchlings possess two mechanisms (crawling and swimming) for the establishment of an offshore heading. The use of these alternative mechanisms probably assures that turtles escape from shore under the broad range of conditions which they naturally encounter after emerging from their nests.
Show less
Date Issued: 1996
PURL: http://purl.flvc.org/fcla/dt/15285
Subject Headings: Loggerhead turtle, Sea turtles--Orientation, Animal navigation
Format: Document (PDF)

Title: The orientation and survival of loggerhead sea turtle hatchlings (Caretta caretta L.) in the nearshore environment.
Creator: Glenn, Lawrence, Florida Atlantic University, Salmon, Michael, Wyneken, Jeanette
Abstract/Description: Hatchling sea turtles emerge at night from underground nests, crawl to the ocean, and swim out to sea. In this study, I determined how offshore orientation and shallow-water predation rates varied under natural (sand bottom and patch reef) and modified (submerged breakwater and open-beach hatchery) ecological circumstances. Hatchling offshore orientation in the sea was normal under all conditions; there were no significant differences in either scatter or direction among groups. However,...
Show moreHatchling sea turtles emerge at night from underground nests, crawl to the ocean, and swim out to sea. In this study, I determined how offshore orientation and shallow-water predation rates varied under natural (sand bottom and patch reef) and modified (submerged breakwater and open-beach hatchery) ecological circumstances. Hatchling offshore orientation in the sea was normal under all conditions; there were no significant differences in either scatter or direction among groups. However, predators (tarpon, snapper, barracuda, jacks, and grouper) took more hatchlings as they swam over submerged reefs, and after they entered the water in front of hatcheries. Predators were concentrated at both of these sites probably because prey (small fishes and invertebrates at patch reefs and turtles entering the water where nests were concentrated in hatcheries) occur in greater abundance.
Show less
Date Issued: 1996
PURL: http://purl.flvc.org/fcla/dt/15282
Subject Headings: Loggerhead turtle, Sea turtles--Orientation, Animal navigation
Format: Document (PDF)

Title: The underwater audiogram of the West Indian manatee (Trichechus manatus latirostris).
Creator: Gerstein, Edmund Roy, Florida Atlantic University, Salmon, Michael
Abstract/Description: The hearing abilities of two adult manatees were tested using a forced two-choice paradigm and an up/down staircase psychometric technique. Prior to this research, no hearing tests or audiograms had been measured for any Sirenian species. This test was also the first controlled underwater infrasonic hearing test conducted on any marine mammal. The audiogram demonstrated a wider range of hearing (0.5 to 38 kHz) and greater sensitivity (50 to 102 dB re:1muPa) throughout this range than had...
Show moreThe hearing abilities of two adult manatees were tested using a forced two-choice paradigm and an up/down staircase psychometric technique. Prior to this research, no hearing tests or audiograms had been measured for any Sirenian species. This test was also the first controlled underwater infrasonic hearing test conducted on any marine mammal. The audiogram demonstrated a wider range of hearing (0.5 to 38 kHz) and greater sensitivity (50 to 102 dB re:1muPa) throughout this range than had previously been suggested by averaged evoked potential and anatomical studies. The audiogram was a typical U-shaped mammalian hearing curve and was compared with other marine mammal underwater audiograms. Both manatees were most sensitive to frequencies between 12-18 kHz at 50-54 dB. The manatees' hearing sensitivity dropped more than 20 dB per octave below 1600 Hz. This higher frequency sensitivity may have evolved as an adaptation to a shallow water existence where low frequency sound propagation is limited. Limited hearing sensitivity at lower frequencies may be a contributing factor to the manatees' vulnerability to boat collisions.
Show less
Date Issued: 1995
PURL: http://purl.flvc.org/fcla/dt/15192
Subject Headings: West Indian manatee, Manatees--Florida, Manatees--Sense organs, Audiometry, Hearing levels
Format: Document (PDF)

Title: Orientation of hatchling loggerhead sea turtles in response to the inclination of the magnetic field.
Creator: Light, Phillip Richard, Florida Atlantic University, Salmon, Michael, Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description: Recent studies have shown that hatchling loggerhead sea turtles possess the ability to orient to the earth's magnetic field. These experiments did not identify the specific component of the field used by turtles to determine direction. One of the field's most important characteristics, inclination, has been implicated as the specific property used by birds to orient. This study investigated the possibility that sea turtles use the inclination of the earth's field in a similar manner. Results...
Show moreRecent studies have shown that hatchling loggerhead sea turtles possess the ability to orient to the earth's magnetic field. These experiments did not identify the specific component of the field used by turtles to determine direction. One of the field's most important characteristics, inclination, has been implicated as the specific property used by birds to orient. This study investigated the possibility that sea turtles use the inclination of the earth's field in a similar manner. Results show that turtles determine direction with the use of an inclination compass similar to the one used by birds to orient. This study has important implications regarding the mechanisms used by animals to orient and navigate.
Show less
Date Issued: 1992
PURL: http://purl.flvc.org/fcla/dt/14787
Subject Headings: Loggerhead turtle, Animal orientation, Magnetic fields, Sea turtles--Migration
Format: Document (PDF)

Title: Effects on beach renourishment on the survival of loggerhead sea turtles.
Creator: Broadwell, Ann L., Florida Atlantic University, Salmon, Michael
Abstract/Description: The fate of loggerhead (Caretta caretta, L.) clutches at four physically different beaches, including a renourished site, was investigated in the Boca Raton area. I compared the four sites with regard to their thermal environment, moisture content, sand grain size, and pore spacing at depths of a typical nest. Significantly more sea turtle hatchlings emerged from nests deposited on the renourished beach than at the other sites. At the renourished beach moisture content and pore spacing were...
Show moreThe fate of loggerhead (Caretta caretta, L.) clutches at four physically different beaches, including a renourished site, was investigated in the Boca Raton area. I compared the four sites with regard to their thermal environment, moisture content, sand grain size, and pore spacing at depths of a typical nest. Significantly more sea turtle hatchlings emerged from nests deposited on the renourished beach than at the other sites. At the renourished beach moisture content and pore spacing were highest. Pore spacing and moisture content correlated negatively with the number of hatchlings which died in the nest, and correlated positively with emergence success. At the natural beach, hatchling weight was lowest and straight-line carapace length (SLC) was shortest. I conclude that at the renourished beach, conditions favored hatchling production. However, that may not be the case in all instances of renourishment, as effects probably vary with the nature of the sands used to replenish the beach.
Show less
Date Issued: 1991
PURL: http://purl.flvc.org/fcla/dt/14749
Subject Headings: Loggerhead turtle--Reproduction, Loggerhead turtle--Florida
Format: Document (PDF)

Title: Can hatchlings exposed to beach lighting recover, and orient normally offshore?.
Creator: Lorne, Jacquelyn Kay, Florida Atlantic University, Salmon, Michael
Abstract/Description: Artificial lighting disrupts sea turtle hatchling orientation from the nest to the sea. I studied how a light-induced landward crawl affects the ability of hatchlings to later crawl to the sea, and swim offshore from a dark beach. A brief (2 min) landward crawl had no effect on orientation, as long as waves (used as an orientation cue while swimming) were present. In the absence of waves (a flat calm sea), landward-crawling hatchlings failed to swim offshore while those crawling seaward were...
Show moreArtificial lighting disrupts sea turtle hatchling orientation from the nest to the sea. I studied how a light-induced landward crawl affects the ability of hatchlings to later crawl to the sea, and swim offshore from a dark beach. A brief (2 min) landward crawl had no effect on orientation, as long as waves (used as an orientation cue while swimming) were present. In the absence of waves (a flat calm sea), landward-crawling hatchlings failed to swim offshore while those crawling seaward were well oriented. A longer (2 h) landward crawl impaired the ability of hatchlings to crawl to the sea. These results demonstrate that previous exposure to artificial lighting compromises subsequent orientation, both on land and in the sea. On the basis of my results, I suggest several changes to current management practices, currently used when releasing misoriented turtles in the wild.
Show less
Date Issued: 2006
PURL: http://purl.flvc.org/fcla/dt/13400
Subject Headings: Sea turtles--Atlantic Coast (U S )--Geographical distribution, Light pollution, Animal orientation, Loggerhead turtle--Orientation, Animal navigation
Format: Document (PDF)

Title: Do embedded roadway lights protect sea turtles?.
Creator: Bertolotti, Lesley L., Florida Atlantic University, Salmon, Michael
Abstract/Description: Pole-mounted street lighting on coastal roadways is often visible in adjacent areas. At roadways near sea turtle nesting beaches, these lights can disrupt the nocturnal orientation of hatchlings as they crawl from the nest to the sea. Our objective was to determine if an alternative lighting system (light-emitting diodes, embedded in the roadway pavement) prevented orientation disruption of loggerhead hatchlings. Hatchlings at the beach oriented normally when the embedded lights were on, or...
Show morePole-mounted street lighting on coastal roadways is often visible in adjacent areas. At roadways near sea turtle nesting beaches, these lights can disrupt the nocturnal orientation of hatchlings as they crawl from the nest to the sea. Our objective was to determine if an alternative lighting system (light-emitting diodes, embedded in the roadway pavement) prevented orientation disruption of loggerhead hatchlings. Hatchlings at the beach oriented normally when the embedded lights were on, or when all lighting was switched off. However, turtles showed poor orientation when exposed to pole-mounted street lighting. Light measurements revealed that street lighting was present at the beach, whereas embedded lighting was absent. I conclude that embedded lighting systems restrict light scatter, leaving adjacent habitats dark, and therefore protect the turtles from artificial lighting allowing for normal seafinding.
Show less
Date Issued: 2005
PURL: http://purl.flvc.org/fcla/dt/13203
Subject Headings: Loggerhead turtle, Animal navigation, Animal orientation, Sea turtles--Orientation, Exterior lighting--Environmental aspects, Light pollution
Format: Document (PDF)

Title: Endogenous programs and the development of sea-finding orientation of loggerhead hatchlings (Caretta caretta).
Creator: Barrett, Christie A., Florida Atlantic University, Salmon, Michael
Abstract/Description: This study's objective was to determine if the transfer of a crawling direction to a magnetic compass in loggerhead hatchling sea turtles ( Caretta caretta L.) was facilitated by how long the turtle crawled (an "endogenous timing" component). I first determined how long it took hatchlings to crawl from their nest to the ocean. Two types of experiments were then carried out. In the first, crawling time varied. In the second, both crawling time and direction varied. I found that at most beaches...
Show moreThis study's objective was to determine if the transfer of a crawling direction to a magnetic compass in loggerhead hatchling sea turtles ( Caretta caretta L.) was facilitated by how long the turtle crawled (an "endogenous timing" component). I first determined how long it took hatchlings to crawl from their nest to the ocean. Two types of experiments were then carried out. In the first, crawling time varied. In the second, both crawling time and direction varied. I found that at most beaches hatchlings crawled to the ocean in less than 5 min. My experiments showed that if crawls are too short (1 min), or too long (5 min), vector transfer is weakened compared to a 2 min crawl. I also found that a period of non-directional crawling interfered with the ability of a 2 min crawl to promote calibration. These results confirm that efficient transfer of a crawling vector, maintained by visual compass, to a swimming vector, maintained by a magnetic compass, depends upon an endogenous timing program in hatchlings. The temporal properties of that program are, in turn, apparently shaped by where their mothers place nests on the beach.
Show less
Date Issued: 2004
PURL: http://purl.flvc.org/fcla/dt/13175
Subject Headings: Animal orientation, Animal navigation, Sea turtles--Orientation, Loggerhead turtle
Format: Document (PDF)

Title: Home range and movements of juvenile Atlantic green turtles (Chelonia mydas L.) on shallow reef habitats in Palm Beach, Florida, United States of America.
Creator: Makowski, Christopher, Florida Atlantic University, Salmon, Michael
Abstract/Description: This study's objectives were to determine if coastal (shallow-water, oceanic reef) aggregations of juvenile green turtles (Chelonia mydas L.) in Palm Beach, Florida occupied distinct home ranges and how these home ranges compared in size and resource availability with those studied elsewhere. Six immature green turtles were captured, measured, and subjected to esophageal lavage to determine diet. Each turtle was returned to its initial capture site within 24 h with an ultrasonic transmitter...
Show moreThis study's objectives were to determine if coastal (shallow-water, oceanic reef) aggregations of juvenile green turtles (Chelonia mydas L.) in Palm Beach, Florida occupied distinct home ranges and how these home ranges compared in size and resource availability with those studied elsewhere. Six immature green turtles were captured, measured, and subjected to esophageal lavage to determine diet. Each turtle was returned to its initial capture site within 24 h with an ultrasonic transmitter used to track movements. All turtles were <65 cm SCL, had ingested similar macroalgae, and occupied markedly small home ranges (mean = 2.38 +/- 1.78 km 2), largely restricted to the reef itself. Diving and feeding activity peaked during the day; at night, activity was minimal. The food and sleeping site resource distribution at this specific location coincides with the turtles' home range size and shape, with considerable overlap of core areas.
Show less
Date Issued: 2004
PURL: http://purl.flvc.org/fcla/dt/13160
Subject Headings: Sea turtles--Florida--Palm Beach, Animal behavior, Wildlife conservation, Green turtle--Florida--Palm Beach
Format: Document (PDF)

Title: Signature whistle stability in wild female Atlantic spotted dolphins, Stenella frontalis.
Creator: Burris, Jennifer., Florida Atlantic University, Salmon, Michael
Abstract/Description: Previous qualitative assessment indicated that signature whistles of temporarily captured, free-ranging dolphins remain stable over periods of 2--12 years. This study reports on the stability of signature whistle parameters in wild female Atlantic spotted dolphins in the Bahamas over five or more years and between changes in age class. Signature whistles from seven female dolphins were pooled into blocks of 'early' and 'late' years for the time assessment. Signature whistles from five females...
Show morePrevious qualitative assessment indicated that signature whistles of temporarily captured, free-ranging dolphins remain stable over periods of 2--12 years. This study reports on the stability of signature whistle parameters in wild female Atlantic spotted dolphins in the Bahamas over five or more years and between changes in age class. Signature whistles from seven female dolphins were pooled into blocks of 'early' and 'late' years for the time assessment. Signature whistles from five females were pooled by age class for the second analysis. Duration, minimum frequency, maximum frequency, and change in frequency were measured from spectrograms of whistles for statistical analysis. No significant changes were found in any of the signature whistle parameters either between early and late periods of time or with a change in age class.
Show less
Date Issued: 2004
PURL: http://purl.flvc.org/fcla/dt/13155
Subject Headings: Dolphins--Physiology, Animal communication, Atlantic spotted dolphin--Behavior, Animal sounds
Format: Document (PDF)

Title: Visual spectral sensitivity of loggerhead (Caretta caretta L.) and leatherback (Dermochelys coriacea L.) hatchlings: A comparative study.
Creator: Gocke, Judith P., Florida Atlantic University, Salmon, Michael
Abstract/Description: In the ocean, lighting varies with habitat; the eye's spectral sensitivity must vary with visual ecology. Green turtles are the only sea turtle whose spectral sensitivity has been studied. Loggerheads and leatherbacks see visible light between 340 and 700 nm. However, the wavelengths detected with the greatest sensitivity by both species are those best transmitted at the specific depths where food, mates and predators are likely to be encountered. Both species have trichromatic vision, but...
Show moreIn the ocean, lighting varies with habitat; the eye's spectral sensitivity must vary with visual ecology. Green turtles are the only sea turtle whose spectral sensitivity has been studied. Loggerheads and leatherbacks see visible light between 340 and 700 nm. However, the wavelengths detected with the greatest sensitivity by both species are those best transmitted at the specific depths where food, mates and predators are likely to be encountered. Both species have trichromatic vision, but the species differ in the concentration and peak sensitivity of each visual pigment resulting in either a broadly tuned (loggerhead) or finely tuned (leatherback) spectral sensitivity. Spectral sensitivity of leatherbacks overlaps both bioluminescence of prey, and light available in clear, deep, oceanic waters.
Show less
Date Issued: 2003
PURL: http://purl.flvc.org/fcla/dt/13029
Subject Headings: Loggerhead turtle, Leatherback turtle, Spectral sensitivity
Format: Document (PDF)

Title: The effects of filtered high-pressure sodium lighting on hatchling loggerhead (Caretta caretta L.) and green turtle ( Chelonia mydas L.) hatchlings.
Creator: Nelson, Kristen Ann, Florida Atlantic University, Salmon, Michael
Abstract/Description: Hatchling sea turtles use visual cues to orient to the water. Streetlights placed on coastal roadways can attract the turtles inland. Filters were designed to be used with coastal roadway lighting to eliminate the more harmful wavelengths of light. I tested the General Electric 2422 and NLW filters in a laboratory setting with hatchling loggerhead and green turtles. Both species of turtles were attracted to the amber filtered lighting in arena experiments. Loggerhead hatchlings were used in T...
Show moreHatchling sea turtles use visual cues to orient to the water. Streetlights placed on coastal roadways can attract the turtles inland. Filters were designed to be used with coastal roadway lighting to eliminate the more harmful wavelengths of light. I tested the General Electric 2422 and NLW filters in a laboratory setting with hatchling loggerhead and green turtles. Both species of turtles were attracted to the amber filtered lighting in arena experiments. Loggerhead hatchlings were used in T-maze experiments where they were given a choice between amber filtered and unfiltered lighting. The turtles preferred the unfiltered lighting to the filtered lighting, even when it was 100 to 1000 times dimmer. I conclude that amber filtered lighting does afford some protection to sea turtles, although it must be used in conjunction with other light management techniques to prevent the disruption of hatchling turtle orientation.
Show less
Date Issued: 2003
PURL: http://purl.flvc.org/fcla/dt/12982
Subject Headings: Loggerhead turtle, Green turtle, Lighting--Environmental aspects
Format: Document (PDF)

Title: How leatherback hatchlings recognize their prey: Sensory predispositions and behavioral responses.
Creator: Constantino, Maricela Alcantara., Florida Atlantic University, Salmon, Michael
Abstract/Description: Leatherback sea turtles (Dermochelys coriacea) feed exclusively on gelatinous prey. Hatchlings are solitary and must possess a predisposition to respond to prey. In laboratory experiments, I studied the responses of nineteen leatherback hatchlings to visual (jellyfish model and shapes: circle, square, diamond) and chemical (homogenates of three prey) stimuli presented alone or as paired (visual + chemical) treatments once daily. When presented alone visual stimuli resembling jellyfish...
Show moreLeatherback sea turtles (Dermochelys coriacea) feed exclusively on gelatinous prey. Hatchlings are solitary and must possess a predisposition to respond to prey. In laboratory experiments, I studied the responses of nineteen leatherback hatchlings to visual (jellyfish model and shapes: circle, square, diamond) and chemical (homogenates of three prey) stimuli presented alone or as paired (visual + chemical) treatments once daily. When presented alone visual stimuli resembling jellyfish outlines elicited stronger feeding responses (changes in locomotion and orientation) than those not resembling jellyfish. Chemical stimuli alone induced a rheotaxis, but responses evoked by some homogenates were stronger than responses to others. Paired stimuli evoked stronger orientation and more consistent increases in swimming (flipper stroke) rate, indicating additive effects. Results suggest that both stimuli elicit food searching behavior and when they begin to forage, hatchlings already possess predispositions to respond to an adaptive array of prey shapes and odors.
Show less
Date Issued: 2002
PURL: http://purl.flvc.org/fcla/dt/12873
Subject Headings: Leatherback turtle, Predation (Biology)
Format: Document (PDF)

Title: Seafinding orientation of hatchlings exposed to filtered lighting: Effects of varying beach conditions.
Creator: Tuxbury, Susan Mary., Florida Atlantic University, Salmon, Michael
Abstract/Description: Under normal conditions, hatchling sea turtles crawl toward the ocean but streetlights placed on coastal roadways can attract the turtles toward land. Two light filters were designed to exclude the shorter light wavelengths most attractive to turtles. I did laboratory tests to determine if green turtle and loggerhead hatchlings oriented normally ("seaward") in the presence of filtered lighting. Light passed through either filter (#2422 acrylic and NLW) attracted the turtles unless coastal...
Show moreUnder normal conditions, hatchling sea turtles crawl toward the ocean but streetlights placed on coastal roadways can attract the turtles toward land. Two light filters were designed to exclude the shorter light wavelengths most attractive to turtles. I did laboratory tests to determine if green turtle and loggerhead hatchlings oriented normally ("seaward") in the presence of filtered lighting. Light passed through either filter (#2422 acrylic and NLW) attracted the turtles unless coastal cues (an elevated horizon) were strong or background (full moon) illumination was present. Green turtles and loggerheads responded differently to the same filters, indicating that neither filter provided adequate protection for both species. I conclude that these filters fail to protect the turtles. Conventional forms of light control (shielding and/or lowering light fixtures, decreasing wattage, or turning off problem lights) remain the best way to shield turtles from the harmful effects of artificial lighting.
Show less
Date Issued: 2001
PURL: http://purl.flvc.org/fcla/dt/12804
Subject Headings: Sea turtles, Light pollution
Format: Document (PDF)

FAU Theses and Dissertations (36)	+ -
FAU Graduate Student Research (7)	+ -
FAU College Collections (1)	+ -
FAU Undergraduate Student Research (1)	+ -

Loggerhead turtle (13)	+ -
Predation (Biology) (6)	+ -
Animal navigation (5)	+ -
Animal orientation (5)	+ -
Sea turtles--Orientation (4)	+ -

Spectral sensitivity (4)	+ -
Animal behavior (3)	+ -
Chelonia mydas (3)	+ -
Green turtle (3)	+ -
Leatherback turtle (3)	+ -
Light pollution (3)	+ -
Phototaxis (3)	+ -
Sea turtles--Nests (3)	+ -
Adaptation (Biology) (2)	+ -
Loggerhead turtle--Florida (2)	+ -
Sea turtles (2)	+ -
Sea turtles--Florida (2)	+ -
Wildlife conservation (2)	+ -
Allometry (1)	+ -
Animal communication (1)	+ -
Animal migration -- Antigua -- Jumbo Bay (1)	+ -
Animal migration--Florida (1)	+ -
Animal orientation -- Antigua -- Jumbo Bay (1)	+ -
Animal orientation--Florida (1)	+ -
Animal sounds (1)	+ -
Atlantic spotted dolphin--Behavior (1)	+ -
Audiometry (1)	+ -
Beach nourishment (1)	+ -
Biological rhythms (1)	+ -
Caretta caretta (1)	+ -

Electronic Thesis or Dissertation (36)	+ -
abstract (5)	+ -
poster (3)	+ -
article (1)	+ -

Florida Atlantic University (34)	+ -
Charles E. Schmidt College of Science (15)	+ -
Department of Biological Sciences (15)	+ -
Graduate College (7)	+ -
Pate, Jessica Hope (3)	+ -

Search In

Pages

Pages

Sort Results By:

Narrow results by:

Collection

Topical Subject

Genre

Language

Creator

Format

Owner