The ability of adult wild Atlantic spotted dolphins (Stenella frontalis) to synchronize vocalizations and behaviors has been found to be a key factor in overcoming much larger bottlenose dolphins during interspecies aggression (Cusick & Herzing, 2014). Furthermore, an adult baseline of behaviors and vocalizations during aggressive events containing synchrony has been established (Myers, Herzing, & Bjorklund, 2017). The present study examines juvenile aggression that contains bouts of synchrony to look at the development of this valuable skill. Differences of duration between adult and juvenile synchronous bouts, lag sequential analyses, frequencies of behavioral classes depending on the age class of the aggressor-recipient dynamic, differences in the frequencies of behavioral classes depending on the synchronous state and aggressorrecipient dynamic, and differences in behavioral classes exhibited by adults and juveniles during different synchronous states were analyzed. Adults, across group size, were able to maintain physical synchrony for a longer duration. Juveniles were often in loose synchronous groups before forming into a tight synchronous group as seen in adult synchrony. Vocal synchrony during adult aggression in terms of synchronized squawks were longer in duration than vocal synchrony during juvenile aggression. Juveniles used more pursuit behaviors during aggression, which indicates practice of a behavior that was found to be the most frequently used in interspecies aggression (Volker, 2016). Additionally, when adults were present in juvenile aggression, they used fewer aggressive behavioral classes demonstrating self-handicapping based on their opponent. This illustrates that there is a learning period for both vocal and physical synchrony for juvenile dolphins and that juvenile aggression, or play-fighting, is an important aspect of the development of these skills. This study is the first to describe juvenile synchrony in a population of wild Atlantic spotted dolphins. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection

The purposes of this dissertation were to identify complex social-cognitive behaviors in a population of wild Atlantic spotted dolphins (Stenella frontalis) using long-term video archives and identify developmental trends in those behaviors. Chapter One analyzed calf behavior during foraging events involving maternal teaching in order to identify mechanisms for sharing information between mother and calf... The calves' behavior was affected by the referencing cues, supporting the presence of joint attention and true teaching behavior....Chapter Two observed the altered benthic foraging behavior of juvenile play groups, in which juveniles took turns chasing the fish and using referencing gestures to reference the position of the fish to other individuals during the chase, despite the ability of these young, independent dolphins to catch fish much more quickly and efficiently alson... The third chapter analyzed social object play in which dolphins passed pieces of seaweed between individuals. The data clarified developmental trends in the play, and suggested social-cognitive abilities needed for participation. / by Courtney Elizabeth Bender. / Thesis (Ph.D.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.

Synchrony between Atlantic spotted dolphins (Stenella frontalis) is crucial for successfully fending off bottlenose dolphins (Tursiops truncatus) during interspecies aggression. The present study examined synchrony in adult Atlantic spotted dolphins during aggressive encounters with bottlenose dolphins. Across group size, aggressive behavioral events increased preceding synchrony, peaked during synchrony, and decreased dramatically after synchrony. Although smaller groups (< 10 dolphins) became synchronous more frequently than larger groups (> 10 dolphins), larger groups remained synchronous longer; however, smaller groups exhibited more frequent aggressive behavioral events during synchrony, suggesting that additional aggressive behaviors may be necessary to compensate for the small group size, whereas larger groups may be able to rely on synchrony alone. Disorganized squawk bouts synchronized as physical synchrony began, but only if coupled with escalating aggressive behaviors. The synchrony during aggressive episodes observed in adult Atlantic spotted dolphins can be used as a baseline to determine the process of the development of this critical skill in juveniles. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2015 / FAU Electronic Theses and Dissertations Collection

Discipline was implemented by mothers and alloparent spotted dolphins (Stenella frontalis) mothers and alloparents on Little Bahama Bank, Bahamas. Disciplinarians were significantly more likely to be adults than juveniles. Although most disciplinarians were female, males were also observed to perform discipline. The recipients of discipline were male and female, and significantly more likely to be calves than juveniles. Pursuit, contact, and display behaviors were used in discipline, however pursuit behaviors were most often observed. Variables such as age class, sex, and parity were not found to influence how discipline was implemented. The durations of all disciplinary pursuits were under thirty seconds, and successful pursuits had slightly shorter duration than unsuccessful pursuits. Disciplinarian success was not significantly influenced by age class, sex, parity, or behavior used. / by Meghan Weinpress. / Thesis (M.S.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.

This study investigated a resident community of Atlantic spotted dolphins (Stenella frontalis) on Little Bahama Bank (LBB) in the Bahamas utilizing a noninvasive molecular approach. Genetic template material was collected and extracted from fecal material of S. frontalis. Fine-scale population structure was found within LBB according to mitochondrial DNA (mtDNA) and microsatellites (Fst = 0.25317, P < 0.0001 and Fst = 0.04491, P < 0.0001, respectively). Three main social clusters (North, Central, South/Roam) exist on LBB and all clusters were found to be genetically distinct according to microsatellite analyses. Mitochondrial haplotypes revealed North and South/Roam were not differentiated, but Central was different from both. When separated by sex, males were less genetically structured than females. Males showed no evidence of structure according to Ost or Rst. / Females of all clusters were differentiated according to microsatellites whereas mtDNA revealed the same pattern in females as was seen for the total population. The structuring patterns of the sexes clearly indicate a pattern of male dispersal and female philopatry for the LBB population. Genetic investigation of mating revealed patterns in the mating system of S. frontalis on LBB. Genotypes of females and offspring were analyzed and revealed that more than two males were required to explain the progeny arrays, indicating promiscuous mating among females. In addition, paternity assessment assigned seven males as fathers to ten of 29 mother-calf pairs. A pattern of reproductive skew according to age was revealed because reproductively successful males were in the oldest age class at the estimated time of conception of the calves. / Patterns in social cluster mating revealed that males from the Central cluster sired offspring with females from both the Central and North clusters, while Roaming males sired offspring with South and Central females indicating that males mate within their social cluster or with females from the next closest cluster. The study has important implications for cetacean research, specifically delphinids. Fine-scale population structure and mating patterns of male and female S. frontalis were revealed through noninvasive methodology presenting a valuable genetic framework with which to support ongoing investigations of life history, behavior, communication and social structure. / by Michelle Lynn Green. / Vita. / Thesis (Ph.D.)--Florida Atlantic University, 2008. / Includes bibliography. / Electronic reproduction. Boca Raton, FL : 2008 Mode of access: World Wide Web.

Personality is defined as inter-individual variation of behavioral traits while maintaining intra-individual stability. The focus of this study was to observe distinct personality trait categories, establish baseline personality trait phenotypes for the juvenile population, and compare the personality phenotypes between different categories, such as sex or generation. Three personality traits were studied—sociability, curiousity, and boldness—based on the percentage of time individuals spent with conspecifics, human researchers, and their mothers, respectively. The surveyed individuals significantly varied positively and negatively from the means of each trait, and no significant difference for any trait was found between males and females, or across time periods. A moderately strong correlation was discovered between two personality traits, boldness and curiousity, suggesting a personality syndrome. The second primary goal was to use the aforementioned baseline to determine if personality traits can be used to predict neophilic behavior specific to human-dolphin communication research. Six of the study subjects were more prone than their peers to engage with the two-way work, and these individuals were more bold—spent less time with their mothers—than the other subjects. This suggests that boldness has some predictive capabilities towards this type of neophilia. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection

Duas espécies de cetáceos apresentam padrões de distribuição peculiares ao longo da costa brasileira, muito provavelmente em resposta às condições hidrográficas e topográficas que ocorrem entre 20 e 33°S. A primeira espécie, a franciscana ou toninha (Pontoporia blainvillei), é um golfinho de distribuição restrita do Brasil até a Argentina, que ocorre primariamente na plataforma continental interna, raramente ultrapassando os 50 m de profundidade. Já a segunda espécie, o golfinho-pintado-do-Atlântico (Stenella frontalis), é um golfinho de distribuição restrita ao Oceano Atlântico, que ocupa principalmente a plataforma continental. Estas duas espécies apresentam hiatos ao longo da sua distribuição no Brasil que tem consequências na morfologia e estrutura genética das espécies. Através da aplicação de diferentes métodos, o principal objetivo deste estudo foi investigar a influência do ambiente marinho no padrão de distribuição e na estrutura genética destas duas espécies com ênfase na costa brasileira. No primeiro capítulo, investigou-se a relação do ambiente marinho com o padrão de distribuição da franciscana. Para tanto, uma revisão e atualização da distribuição das áreas de manejo da franciscana (FMA), e dos limites dos hiatos, ao longo do Brasil foram realizadas. Análises de nicho ecológico sugerem que os hiatos fazem parte do nicho fundamental da franciscana que seriam, portanto, relativamente adequados para a espécie.No entanto, o estreitamento da plataforma continental parece ser o principal fator que explica a ausência da espécie nos hiatos e, inclusive poderia explicar a diferenciação genética entre algumas FMAs No segundo e terceiro capítulos, a relação entre similaridade genética e distâncias geográficas e ambientais foram investigadas para o golfinho-pintado-do- Atlântico em duas escalas: ao longo de praticamente toda distribuição e em uma escala mais restrita com ênfase no Brasil. Populações geneticamente distintas ao longo de toda distribuição da espécie foram identificadas com base em um marcador mitocondrial, que podem ser resultado Isolamento por Distância e Isolamento por Resistência, relacionados tanto com condições ambientais contemporâneas quanto do passado (Último Glacial Máximo). As análises de estrutura populacional do golfinho-pintado-do-Atlântico no Brasil, investigada mais profundamente com marcadores genômicos, indicam ao menos a existência de três populações (Brasil, Colômbia e Oceânica) suportanto, portanto, a hipótese de uma população isolada no sudeste do Brasil. De forma geral, conclui-se que o ambiente marinho e, principalmente, fatores como extensão da plataforma continental, batimetria e temperatura tem um papel fundamental para explicar o padrão de distribuição destas espécies no Brasil. Além disso, outros processos podem estar envolvidos na estruturação genética do golfinho-pintado-do-Atlântico e também da franciscana como, por exemplo, estrutura social, filopatria e a história evolutiva destas espécies. O maior desafio para conservação da franciscana é seu status de Criticamente Ameaçada no Brasil e, em relação ao golfinho-pintado-do-Atlântico é a deficiência de dados. Uma vez que ambas espécies ocorrem na porção mais desenvolvida do país, os resultados aqui obtidos têm impacto direto na conservação destas espécies, porque trazem informações que podem ser utilizadas em planos futuros de conservação e manejo. / Along Brazilian coastal waters, either franciscana and Atlantic spotted dolphins exhibited distributional gaps, which is most likely resulting from changes in the environmental features between 20 and 33°S. The former species, franciscana (Pontoporia blainvillei), is a river dolphin with restricted distribution from Brazil to Argentina, recorded mainly up to 50 m deep over the inner shelf. The second species, Atlantic spotted dolphin (Stenella frontalis), is a delphinine dolphin distributed across the Atlantic Ocean, being mainly recorded over the continental shelf. The distribution patterns that these species showed in Brazil have a direct influence on the morphology/ecology and genetic struture of both species. Different approaches were applied to address the main goal of this study, which was investigating the influence of marine environment in shaping the distribution pattern, as well as genetic strcuture of franciscana and Atlantic spotted dolphin with emphasis in the Brazilian coastal waters. In the first chapter, I investigated the franciscana distribution in Brazil using an ecological niche modeling approach. In order to do that, I performed a review of records of the species along Brazial and, updated the limits of franciscana management areas (FMAs) and distributional gaps. The results suggested that gaps are within franciscana fundamental niche and, therefore, both gaps would be suitable for franciscana. However, the narrow of continental shelf seems to be the main factor inhibiting the presence of franciscana in these areas. Furthermore, the narrowing of continental shelf play a role to explain the genetic differentiation among FMAs. In the second and third chapters, the relationship between genetic distances and geographic and environmental distances were investigated both in a restrict and a broad scale. I found genetically distinct populations 12 across Atlantic spotted dolphin distribution based on mtDNA, that are probably resulting of Isolation-by-Distance and Isolation-by-Resistance related both with contemporary and past conditions (e.g. Last Glacial Maximum). Furthermore, I investigated population struture using genomic markers (Single Nucleotide Polymorphisms, SNPs) across Western South Atlantic, Caribbean and Eastern Atlantic. The results suggested at least three different populations, and therefore, confirmed previous hypothesis of an isolated population in the southeastern Brazil. Overall, I concluded that marine envinronment, especially the extension of continental shelf, bathymetry and sea surface temperature, are the main factors that explaning the distribution pattern of franciscana and Atlantic spotted dolphin in Brazil. Besides that, other process such as, social structure and phylopatry, as well as biogeographical process might be investigated in further studies. Franciscana is considered “Critically endangered” in Brazil, and Atlantic spotted dolphin has not enough data to determine its conservation status. Since both species are recorded in the most developed region of the country with high anthropic pressure, my results could help in future management and conservation plans for both species in a regional scale.

Bottlenose (Tursiops truncatus) and spotted (Stenella frontalis) dolphins are sympatric species, resident to Little Bahama Bank, Bahamas. A unique, dynamic methodology quantified how interspecific aggression changed over time in terms of the individuals participating, context, and behaviors used. The timing of human observation relative to the onset of aggression did not result in differences in the proportion of behaviors observed. Highly intense behaviors were used most often. The synchronous state of spotted dolphin groups, not the presence alone, was a crucial factor in determining the onset and progression of aggression. When synchronous, spotted dolphins successfully dominated the larger bottlenose dolphins. Two levels of dominance were observed. Within a single encounter ("encounter level"), one species did dominate the other. When all aggressive encounters were considered collectively over the long term ("gross level"), one species did not dominate the other. The combination of contextual factors best determined the dynamic of interspecific aggression. / by Jessica A. Cusick. / Thesis (M.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2012. Mode of access: World Wide Web.

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, 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. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection

Odontocetes use echolocation to detect, track, and discriminate their prey, as well as negotiate their environment. Their hearing abilities match the frequency of greatest sensitivity to the higher frequencies used for foraging and navigation. Hearing and echolocation together provide odontocetes with a highly developed biosonar system. This dissertation examines the hearing ability of several odontocete species to understand what signals they can perceive during echolocation. The variability in hearing ranges between species is examined in the context of phylogenetic and ecological differences among taxa. An autonomous hydrophone array is also developed that could be used in an expanded form in field deployments to study echolocation signals in a wider range of species. Methods for measuring hearing sensitivity include both psychophysical and electrophysiological procedures. Behavioral methods require a large time commitment, for both training and data collection, and can only be performed on captive dolphins. Auditory evoked potential (AEP) methods are non-invasive, rapid measurements of the brain's response to sound stimuli and allow for audiograms to be collected on stranded, high risk dolphins. By determining the hearing abilities of odontocetes either in captivity or during stranding, data can be collected about inter- and intraspecies variability, and the occurrence of hearing impairment. It can also be used as another diagnostic tool to determine the releasability of a stranded animal. A juvenile male short-finned pilot whale (Globicephala macrorhynchus) that stranded in Curacao had severe hearing impairment at all frequencies tested. Four female short-finned pilot whales tested had the best sensitivity at 40 kHz. The juveniles had greater high frequency sensitivity than the adult pilot whales. Cutoff frequencies were between 80 and 120 kHz. Hearing sensitivity was determined for the two mother/calf pairs of Risso's dolphins (Grampus griseus) before and after antibiotic treatment in order to measure any potential effects of antibiotic treatment. Greatest sensitivity occurred at 40 kHz and cutoff frequencies were around 120 kHz for all dolphins tested. Changes in hearing sensitivity after antibiotic dosage were 12 dB or less in all cases except one. The adult female Betty showed a threshold shift at 120 kHz of 54 dB from May to June, which partially demonstrates the presence of an ototoxic effect at one frequency. Dosages of antibiotics during drug treatment detailed in this study should be considered safe dosages of antibiotics for Risso's dolphins. AEP and behavioral methods were used to collect audiograms for three Stenella spp. dolphins. The frequency of best hearing for the Atlantic spotted dolphin and the spinner dolphin was 40 kHz, and their upper cutoff frequencies were above 120 kHz. The pantropical spotted dolphin had the greatest sensitivity at 10 kHz, and had severe high frequency hearing loss with a cutoff frequency between 14 and 20 kHz. Comparisons of high frequency hearing sensitivities among the species tested show two distinct groups. Short-finned pilot whales and Risso's dolphins have a cutoff frequency below 120 kHz, whereas Stenella spp. dolphins have cutoff frequencies above 120 kHz. Expanding the comparison to include other species, killer whales, pygmy killer whales, false killer whales, and long-finned pilot whales also have cutoff frequencies below 120 kHz. Common bottlenose dolphins, white-beaked dolphins, Indo-Pacific humpback dolphins, rough-toothed dolphins, and common dolphins have cutoff frequencies above 120 kHz. Genetic evidence exists for two subfamilies within Delphinidae (Vilstrup et al., 2011) and those species with cutoff frequencies below 120 kHz belong to the subfamily Globicephalinae and those species with cutoff frequencies above 120 kHz belong to the subfamily Delphininae. An autonomous, field-deployable hydrophone array was developed to measure free-swimming echolocation. The array contained 25 hydrophones, two cameras, and a synchronization unit on a PVC frame. The distinct click train was used to time-align all 25 channels, and the light was used to synchronize the video and acoustic recordings. Echolocation beam patterns were calculated and preliminary evidence shows a free-swimming dolphin utilizes head movement, beam steering and beam focusing. Among all areas of cetacean biology more research is necessary to gain a clearer picture of how odontocetes have adapted to function in their acoustic environment. The array system developed can be used to study how dolphins use echolocation in the wild, the impacts of anthropogenic sound on echolocation production, and the potential consequences of high frequency hearing loss.