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Peripheral blood leukocyte samples were collected from 151 common bottlenose dolphins (Tursiops truncatus) in the course of capture/release health evaluation studies at four different sites: Charleston Harbor, SC; Indian River Lagoon, FL; Sarasota Bay, FL; and St. Joseph Bay, FL. RNA was extracted and hybridized to a first-generation dolphin microarray. We tested the hypothesis that individual dolphins could be assigned to their home regions (by machine learning methods) using only their transcriptomic signatures as classifiers. The machine learning approaches used in this study were artificial neural networks (ANNs) which were able to identify gene expression differences in males and females in some geographical locations. As the sex ratios sampled in each location were not the same and could influence the classification of individuals to locations, males and females at each location were considered separately. ANNs were able to correctly classify dolphins according to their site of sampling with a high degree of confidence. The basis for this result may lie in genetic differences between populations, or in environmental factors (including for example diet, infection, contaminant load, or exposure to biotoxins) or in combinations of these factors. These results suggest that a combination of microarrays and machine learning analytical approaches will be a powerful approach to understanding the interaction of dolphins with the marine environment.

The concentrations of total mercury in muscle (17 samples), liver (16 samples) and kidney tissues (16 samples) of both bottlenose (Tursiops truncatus) and striped dolphins (Stenella coeruloalba) were analyzed by cold vapour atomic absorption (AA) spectroscopy. The dolphins were found dead at different locations along the east Adriatic over a 10-year period starting in 1990. In this study, the magnitude of mercury contamination of dolphins which are indicators of contamination of the Adriatic as well as the Mediterranean Sea was determined. Our results represent the first investigation of heavy metal concentrations in dolphins sampled along the Croatian coast of the Adriatic Sea. Total mercury levels were high, ranging from 1.51 to 136.7 mg/kg in muscle, from 2.04 to 143.1 in kidney and from 10.35 to 1 833 mg/kg in liver tissues (expressed as wet weight). These results were examined for differences based upon age and tissue type. A high correlation was observed between total mercury concentration and age, and adult dolphins (10 samples) contained statistically significant higher concentrations of mercury compared to juvenile (seven samples) dolphins. Mercury concentrations were generally the highest in liver tissue. The presence of high mercury levels in dolphins is attributed to natural as well as anthropogenic sources.

Knowledge of demographic parameters of most cetacean populations is scarce because of problems associated with sampling open populations of wide-ranging animals. In recent years, capture–recapture models have been developed to address these problems. We used a photo-identification dataset collected from a population of bottlenose dolphins Tursiops truncatus between 1999 and 2004 around 2 islands of the Azores archipelago, to demonstrate the use of some of these methods. A variety of open models and Pollock’s robust design were applied to estimate population size, survival probability and emigration rates. Using only the estimates with the lowest coefficients of variation, the annual abundance of adult dolphins varied between 202 (95% CI: 148 to 277) and 334 (95% CI: 237 to 469), according to the Jolly-Seber method, and between 114 (95% CI: 85 to 152) and 288 (95% CI: 196 to 423), according to the robust design. The number of subadult individuals varied from 300 (95% CI: 232 to 387) to 434 (95% CI: 316 to 597) based on the Jolly-Seber method. The open models yielded estimates of adult survival (0.970 ± 0.029 SE) that were significantly higher than those for subadults (0.815 ± 0.083 SE). Movement patterns of dolphins in the Azores seem to follow a Markovian model, in which dolphins seen in the study area in 1 yr show higher probability of emigrating in the following year. Despite some limitations, this is the first study to model transience and temporary emigration in a dolphin population. Publisher PDF

One of the first steps in understanding the relationships between populations and their habitats is to determine which areas they use with higher frequency. This study used systematic and non-systematic survey data from 2001-2002 and 2004-2012 to determine encounter rates and investigate temporal and spatial distribution of bottlenose dolphins around Madeira, Desertas and Porto Santo islands. A total 24,914 km of search effort was carried out and 199 sightings were recorded. Highest encounter rates were found off the east coast of Madeira and off Porto Santo. Moreover, higher encounter rates occurred over bathymetries ranging between 500-1,000 m during systematic surveys whereas in nonsystematic surveys relative high encounter rates were found in depths of 2,000-2,500m. Most dolphins were found to be distributed in depths

Bottlenose dolphins (Tursiops truncatus) kept in zoos and dolphinarias rarely get an outlet for their echolocation abilities as their pool environment is often quite barren. Not much research has been carried out on enrichments promoting echolocation for dolphins in human care. In the present study a setup with live fish was compared to a setup with air-filled floats (providing strong sonar targets, similar to the swim bladders of large fish) and a control setup. A PCL (porpoise click logger) was used to record the echolocation click trains produced by the dolphins and aimed at the three setups. Behavioural data was also collected from video footage. Both the PCL data and all the behavioural observations indicated that the fish setup was more interesting than the float and the control setup, for the dolphins to echolocate towards. However, there were some contradictions with some parameters, where the floats and control seemed to be more interesting. This was probably due to the location of the PCL hydrophone in relation to the floats and fish, and not because the dolphins had a real bigger interest in these setups. To increase the possibility for dolphins to perform more echolocation in human care and increase their welfare, live fish can be recommended as echolocation enrichment.

The Lower River Shannon is a Special Area of Conservation (SAC) with bottlenose dolphins (Tursiops truncatus) as a qualifying interest, and is one of only two SACs for this species in Ireland. Bottlenose dolphins in the Shannon Estuary are present year-round and genetically discrete from other populations in Ireland. They have regularly been reported from Tralee Bay and Brandon Bay, Co. Kerry, adjacent to the Lower River Shannon SAC boundary. In order to determine the provenance of these dolphins, photo-identification data collected between 2008 and 2016 from both bays were used to identify individuals and match them to existing bottlenose dolphin catalogues in Ireland. Bottlenose dolphins were observed on over 90% of the 13 trips carried out,with photo-identification data collected on 11 of these trips. A total of 70 individual dolphins were identified, of which 67 have been regularly recorded within the Lower River Shannon SAC, confirming them to be from this population. Shannon dolphins represented an average of 98% of dolphins photographed during each survey. Of the estimated 108 individual adult dolphins extant in the Shannon population, 62% were identified in Brandon Bay and/ or Tralee Bay during the study period. A discovery curve of individuals identified did not reach a plateau, suggesting that not all dolphins occurring in these bays were photographed during the study. Results suggest that these areas are of high importance to the Shannon dolphin population and support the need to extend the current boundary of the Lower River Shannon SAC to include Brandon Bay and Tralee Bay. yes

Our findings could stimulate study of public health implications of diseases caused by this fungus., Cutaneous granulomas in dolphins were believed to be caused by Lacazia loboi, which also causes a similar disease in humans. This hypothesis was recently challenged by reports that fungal DNA sequences from dolphins grouped this pathogen with Paracoccidioides brasiliensis. We conducted phylogenetic analysis of fungi from 6 bottlenose dolphins (Tursiops truncatus) with cutaneous granulomas and chains of yeast cells in infected tissues. Kex gene sequences of P. brasiliensis from dolphins showed 100% homology with sequences from cultivated P. brasiliensis, 73% with those of L. loboi, and 93% with those of P. lutzii. Parsimony analysis placed DNA sequences from dolphins within a cluster with human P. brasiliensis strains. This cluster was the sister taxon to P. lutzii and L. loboi. Our molecular data support previous findings and suggest that a novel uncultivated strain of P. brasiliensis restricted to cutaneous lesions in dolphins is probably the cause of lacaziosis/lobomycosis, herein referred to as paracoccidioidomycosis ceti.

Insufficient data regarding abundance, distribution and movement patterns of bottlenose dolphins has contributed to lack of effective conservation strategies within the Levantine Sea. It has been inferred that the bottlenose dolphin population has decreased by 30 % in the last 60 years, thus a basin wide research effort on the population is an urgent priority. We present the preliminary results of the first bottlenose dolphin photo-identification study in the northwestern Levantine Sea. 32 boat surveys were conducted from March 2015 to July 2016, totalling 1433 km of survey effort. Current study reported an uneven distribution, high seasonal encounters and varied residency patterns of bottlenose dolphins within the northwestern Levantine Sea. We propose that the northwestern Levantine Sea, specifically the coastal waters of Antalya Bay, indeed is an important bottlenose dolphin habitat and adjacent waters may be of similar significance. Of the 56 individuals catalogued, 13 were re-sighted in both years. Encounter rates varied seasonally, with a peak in spring of 12 groups and 100 individuals per 100 km. Dolphin presence was not detected during autumn and winter. While seasonal, visitor and transient dolphins were reported, no year-round residency was documented. Incidental observations of visible starvation signs and skin parasites suggested individual dolphins in this region could be under anthropogenic stressors. The results reported here highlight the importance of baseline information on encounter rate, distribution and residency pattern as they have a key role on the assessment of population statues and the threats they are facing. Future studies with annual survey effort, have to be continued in the northwestern Levantine Sea and its adjacent waters.

One of the most common applications in isotopic ecology is the assessment of animal's assimilated diet through mass-balance mixing models. Its applicability relies on the use of accurate diet to tissue discrimination factors and turnover rates, which are known to vary as a function of several factors including taxon or tissue type. To date, few studies have assessed isotopic discrimination factors and turnover rates in cetacean species under controlled conditions. Previous experimental studies focused on blood, a difficult sample to obtain in the wild, or on a more appropriate tissue, the skin, but assessed in short experimental trials without arriving to the isotopic equilibrium. We carried out the longest controlled feeding experiment available (350 days) in bottlenose dolphins (Tursiops truncatus) in order to assess discrimination factors and turnover rates in skin. Animals' isotopic composition was first stabilized by maintaining individuals under an isotopically constant diet during 172 days. Afterwards, diet was shifted and maintained during 178days to calculate isotopic discrimination and turnover rates. Estimates for isotopic discrimination factors were 1.01±0.37‰ (mean±sd) for δC and 1.57±0.52‰ for δN. Half-life turnover rates were estimated to be 24.16±8.19days for carbon and 47.63±19days for nitrogen. This is the first time that applicable values are available to assess the diet of free ranging small cetaceans through stable isotope mixing model analysis., This work was supported by the Fundación Loro Parque, CEPSA (Compañía Española de Petroleos S.A.), and Spanish Ministry of Economy and Competitiveness [CGL2011-25543, EcoCet Project; SEV-2012-0262, Severo Ochoa Programme for Centres of Excellence in R + D + I to J.G and R. dS and Juan de la Cierva Postdoctoral program to R. dS].

Whistles are key elements in the acoustic repertoire of bottlenose dolphins. In this species, the frequency contours of whistles are used as individual signatures. Assessing the long-lasting stability of such stereotyped signals, and the abundant production of non-stereotyped whistles in the wild, is relevant to a more complete understanding of their biological function. Additionally, studying the effects of group size and activity patterns on whistle emission rate may provide insights into the use of these calls. In this study, we document the decades-long occurrence of whistles with stereotyped frequency contours in a population of wild bottlenose dolphins, resident in the region of the Sado estuary, Portugal. Confirmed stereotypy throughout more than 20 years, and positive identification using the signature identification (SIGID) criteria, suggests that the identified stereotyped whistles are in fact signature whistles. The potential roles of non-stereotyped whistles, which represent 68 % of all whistles recorded, are still unclear and should be further investigated. Emission rates were significantly higher during food-related events. Finally, our data show a comparatively high overall whistle production for this population, and no positive correlation between group size and emission rates, suggesting social or environmental restriction mechanisms in vocal production. info:eu-repo/semantics/publishedVersion

Mercury (Hg) is a ubiquitous global contaminant with important public health implications. Mercury is released from a variety of anthropogenic, industrial processes, enters the earth's atmosphere and is re-deposited onto the earth’s surface in rainfall. Much of this Hg enters the oceans which cover the majority of the earth’s surface. In the marine environment, inorganic Hg is converted to the most toxic form of the element, methylmercury, and biomagnified through the trophic levels of the food web. The bottlenose dolphin (Tursiops truncatus) is the apex predator in many estuarine and coastal ecosystems. Due to their long life span and trophic position, bottlenose dolphins bioaccumulate high concentrations of contaminants including Hg, thus making them an important sentinel species for ecosystem and public health. Bottlenose dolphins in Florida bioaccumulate high concentrations of Hg in their blood, skin and internal organs. The concentrations of Hg in blood and skin of bottlenose dolphins of the Indian River Lagoon, FL (IRL) are among the highest reported world-wide. In previous studies, we demonstrated associations between concentrations of total Hg in the blood and skin of IRL dolphins and markers of endocrine, renal, hepatic, hematologic and immune system dysfunction. The predominant manifestation of exposure to mercury in humans is neurotoxicity. During the 1950s and 1960s, residents of Minamata bay, Japan were exposed to high concentrations of methyl mercury as the result of ingestion of fish and shellfish that had become contaminated in this infamous environmental disaster. Affected adults had severe motor and sensory abnormalities often leading to death. Methyl mercury crosses the placenta during pregnancy. Children exposed in utero were born with multiple congenital anomalies and also suffered from neurologic disorders. Significantly, local cats that consumed Hg contaminated fish developed severe signs of neurotoxicity which led to their subsequent description as the “dancing cats of Minamata bay”. Unfortunately, the cause of these strange manifestations in cats was not recognized in time to prevent hundreds of additional cases from occurring. More recent studies have shown that exposure to mercury as a result of seafood consumption during pregnancy may result in multiple cognitive and neurodevelopmental effects in children. The levels of mercury found in bottlenose dolphins and the health effects we identified alerted us to the possibility of an important public health hazard. The IRL occupies 40 percent of the east coast of Florida and is bordered by counties with approximately 2.5 million human inhabitants. Therefore, we hypothesized that local inhabitants in communities bordering the IRL could be at risk of exposure to Hg from the consumption of fish and shellfish. We measured hair Hg in 135 local residents and found a mean concentration of 1.53 µg/g which was higher than that from previous studies of sport fishermen and coastal residents in other states. Over 50% of participants had a hair Hg concentration which exceeded the U.S. EPA exposure guideline. Hair Hg concentration was directly related to the frequency of seafood consumption and to the proportion of fish and shellfish obtained from local recreational sources. This study clearly exemplifies the importance of an animal sentinel in identifying a public health hazard and is virtually unique in “closing the loop” between animal and human health.

The aim of the present study was to investigate the effect of observing other’s movements on subsequent performance in bottlenose dolphins. The imitative ability of non-human animals has intrigued a number of researchers. So far, however, studies in dolphins have been confined to intentional imitation concerned with the explicit request to imitate other agents. In the absence of instruction to imitate, do dolphins (un)intentionally replicate other’s movement features? To test this, dolphins were filmed while reaching and touching a stimulus before and after observing another dolphin (i.e., model) performing the same action. All videos were reviewed and segmented in order to extract the relevant movements. A marker was inserted post hoc via software on the videos upon the anatomical landmark of interest (i.e., rostrum) and was tracked throughout the time course of the movement sequence. The movement was analyzed using an in-house software developed to perform two-dimensional (2D) post hoc kinematic analysis. The results indicate that dolphins’ kinematics is sensitive to other’s movement features. Movements performed for the “visuomotor priming” condition were characterized by a kinematic pattern similar to that performed by the observed dolphin (i.e., model). Addressing the issue of spontaneous imitation in bottlenose dolphins might allow ascertaining whether the potential or impulse to produce an imitative action is generated, not just when they intend to imitate, but whenever they watch another conspecific’s behavior. In closing, this will clarify whether motor representational capacity is a by-product of factors specific to humans or whether more general characteristics such as processes of associative learning prompted by high level of encephalization could help to explain the evolution of this ability.

Bottlenose dolphins are known to use signature whistles to identify conspecifics auditorily. However, the way in which they recognize individuals visually is less well known. We investigated their visual recognition of familiar human individuals under the spontaneous discrimination task. In each trial, the main trainer appeared from behind a panel. In test trials, two persons (one was the main trainer) appeared from the left and right sides of the panel and moved along the poolside in opposite directions. Three of the four dolphins spontaneously followed their main trainers significantly above the level of chance. Subsequent tests, however, revealed that when the two persons wore identical clothing, the following response deteriorated. This suggests that dolphins can spontaneously discriminate human individuals using visual cues, but they do not utilize facial cues, but body area for this discrimination.

Low genetic diversity diminishes the potential to adapt to change and thus reduces individual fitness as well as population viability. Therefore, it is crucial to identify genetic variation that affects fitness and population viability. Until recently, the search for the genetic basis of fitness variation, and the related field of conservation genetics, have mostly relied on neutral genetic markers, such as mitochondrial DNA and microsatellites. However, ecological and evolutionary processes relevant to fitness can only be inferred by non-neutral genes, such as those of the major histocompatibility complex (MHC). In this thesis I examined the interplay between demographic parameters, fitness and MHC genetic diversity of two West Australian populations of bottlenose dolphins (Tursiops cf aduncus): a large population (N ≈ 3000), in Shark Bay (SB) and a much smaller population (N ≈ 250) off Bunbury (BB). With collaborators, I assessed demographic parameters, characterized MHC variation, and investigated the relationship between fitness and MHC diversity. In chapter 2, our demographic analysis showed that the SB population, which is comparatively unimpacted by human activity, was much larger and displayed greater reproductive output than the urban BB population. Reproductive rates of the SB population showed large temporal fluctuations. In chapter 3, using a combination of Sanger and next-generation Illumina MiSeq sequencing, we identified a large variety of MHC sequence variants. We also classified MHC supertypes, variants which encode particular antigen binding sites with differing physiochemical properties. These MHC supertypes may serve as an improved marker for biologically relevant genetic variation. Transcription of some of the MHC sequence variants was confirmed in both populations. Chapter 4 shows that the larger SB population displayed greater MHC diversity—nucleotide diversity and a novel measure of ‘supertype diversity’—than the BB population. The SB population is, therefore, potentially more robust to environmental changes. In chapter 5 we report a strong association between MHC diversity and individual fitness: For example, offspring produced by mothers who were heterozygous for one MHC locus were much more likely to survive to weaning age, than offspring of homozygous mothers. Thus the MHC variation identified in this thesis provides a reliable basis for further studies on the relationship between genetic diversity, fitness and population biology.

The stomach contents of 12 bottlenose dolphins were examined. Ten of the 11 samples originated from dolphins that stranded on the west coast of Ireland between 1999 and 2011, while the remaining dolphin was bycaught. Ten of the stomachs contained food remains, mainly fish bones and otoliths; two stomachs were empty. A total of 37 prey taxa were identified, suggesting that they have a broad diet. The main prey items identified were five gadoid fish. Also, four species were only identified from nonotolith skeletal material, highlighting the importance of including all skeletal material in dietary studies. Three distinct populations of bottlenose dolphins have been identified in Irish waters using genetic markers. Differences in diet were found among these populations, where their stomach contents suggest that these animals might be foraging in different habitats. Significant differences were found between dolphins stranded alive and those that were found dead where the former appeared to have been feeding more on pelagic species. Significant differences were also found between male and female dolphin diet: males had eaten a wider variety of prey items than females. Annual consumption rates for the coastal bottlenose dolphin population in Irish Atlantic coastal waters are estimated to be around 1,193.8 tonnes., SI

"ntroduction: Alphaherpesviruses have been associated with fatal systemic infections in several cetartiodactyla species. The main goal in this paper is to identify microorganisms in wild bottlenose dolphin samples were taken from animals in Campeche, Mexico. Methods: Eight free-living bottlenose dolphins (Tursiops truncatus) from the Terminos Lagoon, Mexico, were captured, sampled and released. The animals were sampled for their blood, blow hole secretion, vaginal or prepuce discharge and skin. From the exudates, the cytology was examined, and cell inoculation was performed using bovine kidney cells (MDBK), African green monkey kidney cells (VERO), canine kidney cells (MDCK) and porcine kidney cells (PK15). Results: After observing the cytopathic effects, the isolates were replicated in the same cell line at least three times. Three isolates were obtained that had a cytolytic effect at 48 – 72 hr. A previously described nested PCR targeting highly conserved regions of the herpesvirus DNA polymerase was performed, as well as transmission electron microscopy (TEM) and immunofluorescence on the infected MDBK cells. Discussion and conclusions: The animals from which the isolates were obtained were clinically healthy at the time of their capture, and it is likely that these animals act as carriers or reservoirs of the virus."

Interactions between bottlenose dolphins (Tursiops truncatus) and fisheries are an increasing problem in the Mediterranean and effective management measures are needed. In order to assess the impact of dolphin interactions on artisanal trammel nets, we examine 354 fishing operations performed in waters of the Archipelago de La Maddalena (Italy). We evaluate whether interactions were related to the species composition of the catch and, using the local commercial value of the target species, we assess whether there was a real economic loss for fishermen. Bayesian models and partial correspondence analysis were used to determine the extent to which dolphin interactions and habitat differences contributed to variation in the species composition of catches. CPUE for fishing operations with no dolphin interactions was significantly higher than that for operations with dolphin interactions, although clearly this does not confirm a direct causal link, and associated economic loss was estimated to be non-significant. Geographic location, season, depth of seabed, moon phase, and mesh size were all important factors affecting the amount and species composition of the catch. Our results suggest that it is likely that these differences in species composition are due to a mixture of habitat and dolphin-induced effects.

International audience; Environmental conditions can shape genetic and morphological divergence. Release of new habitats during historical environmental changes was a major driver of evolutionary diversification. Here, forces shaping population structure and ecotype differentiation (‘pelagic’ and ‘coastal’) of bottlenose dolphins in the North-east Atlantic were investigated using complementary evolutionary and ecological approaches. Inference of population demographic history using approximate Bayesian computation indicated that coastal populations were likely founded by the Atlantic pelagic population after the Last Glacial Maxima probably as a result of newly available coastal ecological niches. Pelagic dolphins from the Atlantic and the Mediterranean Sea likely diverged during a period of high productivity in the Mediterranean Sea. Genetic differentiation between coastal and pelagic ecotypes may be maintained by niche specializations, as indicated by stable isotope and stomach content analyses, and social behaviour. The two ecotypes were only weakly morphologically segregated in contrast to other parts of the World Ocean. This may be linked to weak contrasts between coastal and pelagic habitats and/or a relatively recent divergence.We suggest that ecological opportunity to specialize is a major driver of genetic and morphological divergence. Combining genetic, ecological and morphological approaches is essential to understanding the population structure of mobile and cryptic species.

Complex interactions between environmental factors and behavioral traits may shape the fine and large scale structuring patterns of animal species. The objectives of this dissertation were to describe and understand i) the fine-scale social, ecological and genetic structures of bottlenose dolphins in the Normano-Breton (NB) gulf and ii) the population structure of the species at the scale of the North-East Atlantic (NEA) by combining social, genetic, stable isotope and morphometric approaches. Coastal bottlenose dolphins in the NB gulf form a single genetic population subdivided in three social and ecological clusters. Ecology but not kinship may influence association patterns. In the NEA, bottlenose dolphin genetic structure is hierarchical. They form two ecotypes, i.e. coastal and pelagic, each of them being further divided in two populations. This genetic structure was likely triggered by past changes in the environment (i.e. deglaciation) that created ecological opportunities for diversification. Ecological specializations and social behavior may maintain genetic divergence. In turn, the pelagic origin of bottlenose dolphins in the NB gulf may explain some of their social structure traits. Thus, an interaction between social and ecological behaviors, current and past environmental conditions, and evolutionary history may drive the fine and large scale structuring patterns of this top predator. The absence of strong differences in morphology between the two ecotypes may be explained by their relatively recent divergence or by low contrasts between the pelagic and coastal habitats in the NEA. This work highlights the power of combining approaches at different temporal and spatial scales for assessing the social and population structures of highly mobile and difficult to access species. The results have also major conservation implications especially for the designation of management units., Les patrons de structuration des espèces animales à fine et à large échelles peuvent être façonnés par des facteurs environnementaux et des traits comportementaux individuels. Les objectifs de cette thèse combinant des approches sociales, génétiques, isotopiques et morphométriques sont de décrire et comprendre i) les structures sociale, écologique et génétique de la population de grands dauphins du golfe Normand-Breton (NB) et ii) la structure de population de l'espèce à l'échelle de l'Atlantique Nord-Est (ANE). Les grands dauphins du golfe NB forment une unique population génétique qui est composée de trois ensembles sociaux et écologiques distincts. Les associations entre individus semblent être influencées par l'écologie et non par les liens de parenté. La structure génétique du grand dauphin à l'échelle de l'ANE est hiérarchique, avec deux écotypes, l'un côtier et l'autre pélagique, qui sont chacun divisé en deux populations. Les populations côtières sont issues d'une population pélagique et auraient colonisé les habitats côtiers libérés lors de la dernière déglaciation, ce qui a permis la diversification de l'espèce. Cette structure semble maintenue par les spécialisations écologiques et le comportement social des individus. Par ailleurs, l'origine pélagique des grands dauphins du golfe NB pourrait expliquer certains de leurs traits sociaux. Pour conclure, les patrons de structuration à fine et à large échelles de ce prédateur supérieur semblent influencés par les comportements sociaux et écologiques, les conditions environnementales présentes et passées ainsi que par son histoire évolutive. L'absence de différences morphologiques marquées entre les deux écotypes pourrait s'expliquer par leur divergence relativement récente ou par un faible contraste entre les habitats pélagiques et côtiers dans l'ANE. Ce travail souligne l'intérêt de combiner de multiples approches à différentes échelles temporelles et spatiales pour comprendre la structure sociale et la structure de population d'espèces mobiles et cryptiques. Ces résultats ont également des implications majeures pour la conservation, en particulier pour la définition d'unités de gestion.

This study investigated whether dolphins would show evidence of equivalence class formation between auditory stimuli. Bottlenose dolphins were trained to press one or other of two response levers depending on which one of four auditory stimuli had been previously presented. Once they had learned the initial discriminations, the stimulus-lever contingencies was repeatedly reversed. Within any given session, however, pressing of one lever always led to reward with one set of two tones and pressing the other lever led to non-reward with an alternative set of two tones. After sufficient experience with this response reversal procedure, the dolphins spontaneously chose the same levers they had first learned to be correct with one of the across-set stimulus pairs when later in the session they were presented with the other of the across-set stimulus pairs. They thus demonstrated that they had associated the tones belonging to the two sets within two separate functional classes. It is discussed why the dolphins succeeded with auditory stimuli when they had previously failed in a similar task with visual stimuli.

Organic contaminants continue to enter coastal ecosystems, creating stress for animals that inhabit these areas. A variety of factors such as land use, climate, and habitat usage have the potential to impact the accumulation and effects of these organic chemicals. At the same time, the role of these factors in modifying accumulation or contaminant effects at one trophic level can have indirect impacts on higher trophic levels. One example of a negatively impacted coastal ecosystem where land use and climate impact the effects of organic contaminants is the Charleston Harbor estuarine area in Charleston, South Carolina. The objective of this set of studies was to examine the impacts of shifts in land use and climate on contaminant uptake in the Charleston Harbor ecosystem. To better understand these effects at different trophic levels, the bottlenose dolphin was selected as a representative sentinel species. Atlantic croaker was selected as a representative dolphin prey species. The first objective was to use GIS modeling techniques to investigate the relationship between environmental factors and body burdens of organic contaminants in bottlenose dolphins and in dolphin prey fish (e.g. Atlantic croaker). The second objective was to focus on the effects of changing temperatures on uptake of triclosan (a poorly understood antimicrobial chemical with increasing environmental concentrations) in Atlantic croaker in a lab environment as well as to study effects of this chemical on croaker physiology using a series of reflex action mortality predictors (RAMP). The final objective was to explore the effects of triclosan on anti-predator behavior in Atlantic croaker, specifically whether increased exposure would make Atlantic croaker more vulnerable to predation by impacting the strategies used by fish to escape a simulated predator or burst swimming performance. The two triclosan studies consisted of 64 fish randomly assigned to one of four treatment groups which represented a combination of two temperatures and triclosan exposure or no triclosan exposure. The GIS study found that the most important variables in predicting dolphin contaminant loads included a combination of land use characteristics, prey fish characteristics, and characteristics of the individual dolphin, demonstrating the importance of looking at various factors simultaneously. Additionally, some variables were important in fish models but not dolphin models, meaning they could indirectly impact dolphin contaminant body burdens. This study also found that preferential predation on highly contaminated fish may play a role in dolphin contaminant concentrations. The lab studies of triclosan accumulation and effects in Atlantic croaker found that exposure to triclosan at a higher water temperature led to significantly higher accumulation of triclosan than exposure at a lower temperature. Exposure to triclosan, but not changes in water temperature, significantly negatively impacted fish reflexes, specifically resulting in the loss of the dorsal spine reflex. This reflex did not return in any fish during a 5 week reflex recovery trial. The impact of triclosan on the dorsal spine reflex may provide insight into the other sublethal effects of triclosan as well as potential impacts on social patterning in these fish. Triclosan exposure also significantly impacted the strategies employed by croaker to escape a simulated predator, with triclosan exposed fish spending more time stationary than their non-exposed counterparts. There was no effect of water temperature on the strategies used. All four groups were significantly different from one another in terms of swimming performance. The most important factor discriminating between both low and high water temperature as well as control and triclosan groups was total food consumed. Actual triclosan body burden only had a significant effect on the ninth principle component which represents only 0.07% of the total variance in the data. Notably, this was the only principle component where the number of bursts loads strongly. The effects of water temperature on triclosan accumulation as well as the effects of triclosan exposure on anti-predator behavior may lead to differential predation for croaker and have impacts on bioaccumulation in higher trophic level species that consume croaker.

Submitted by William Justo Figueiro (williamjf) on 2015-06-15T23:23:28Z No. of bitstreams: 1 18.pdf: 1003465 bytes, checksum: 4ec0188cddd4cd7f3d6c8b0b4e08a5b0 (MD5) Made available in DSpace on 2015-06-15T23:23:28Z (GMT). No. of bitstreams: 1 18.pdf: 1003465 bytes, checksum: 4ec0188cddd4cd7f3d6c8b0b4e08a5b0 (MD5) Previous issue date: 2013-02 Nenhuma Espécimes depositados em coleções científicas são uma importante fonte de DNA para identificações taxonômicas e estudos de genética de populações. Isso é especialmente verdadeiro para as espécies raras, as quais têm um grande valor científico em função do seu pequeno tamanho amostral em museus. Além disso, muitas vezes, o acesso às coleções para a realização de estudos moleculares sobre estes táxons só é possível através do uso de técnicas de extração de DNA não-invasivas. Um método alternativo que evita a destruição das amostras de museus e de extração eficiente é apresentado no presente trabalho para quatro exemplares de boto-da-tainha (Tursiops truncatus) coletados ao longo da costa de Santa Catarina, Brasil, entre os anos de 1985 e 2007. Com o auxílio de uma furadeira (modelo Bosch GSR 14,4-2) com brocas de cerca de 2 mm foram feitos pequenos furos em dentes de espécimes fisicamente adultos de Tursiops truncatus da coleção do Laboratório de Mamíferos Aquáticos da Universidade Federal de Santa Catarina (LAMAQ/UFSC). Foram retirados entre 100-150 mg de pó de dentina/cemento e desmineralizados por 7 dias à 55º C com 950 µl de EDTA (0,5 M; pH 8). Este material foi incubado à 55º C overnight para que as células sofressem digestão de proteínas e RNA pela ação de 300 µl de Tampão ATL, 20 µl de Proteinase K e 1 µl de RNAse. A etapa final foi concluída pelo kit de extração Qiagen DNA Investigator (QIAGEN®). A eficiência do DNA extraído foi testada através da amplificação de um fragmento de no mínimo 362 pares de base (pb) da região controladora do DNA mitocondrial em quatro espécimes de T. truncatus. Um total de dois haplótipos com 11 sítios polimórficos foram encontrados. O alto polimorfismo observado é uma possível decorrência da grande variabilidade genética do gênero Tursiops. Em casos onde existe a hipótese de subespécies baseada em caracteres morfológicos, a identificação molecular pode ajudar a atribuir os espécimes de museus a cada ecótipo, sendo de extrema importância o uso de métodos de extração eficientes e não-invasivos, como o demonstrado aqui, para a obtenção de resultados satisfatórios e preservação dos exemplares. Museum specimens are an important source of DNA for taxonomic identifications and population genetics studies. This is especially true for rare species, which has great scientific value due to its small sample size in museums. Moreover, often, access to collections for performing molecular studies on these taxa is only possible through the use of nondestructive DNA extraction techniques. An alternative method, which avoids the destruction of museum samples and with an efficient DNA extraction is presented here for four bottlenose dolphins (Tursiops truncatus) specimens collected along the coast of Santa Catarina, Brazil, from 1985 to 2007. This is the first study in Brazil to amplify teeth DNA of T. truncatus for the mtDNA control region. Using a drill (Bosch GSR 14.4-2 model) with drill bits of about 2 mm, small holes were made in teeth of specimens of Tursiops truncatus physically adults deposited in the collection of the Laboratório de Mamíferos Aquáticos, Universidade Federal de Santa Catarina (LAMAQ/UFSC). Between 100-150 mg of powdered dentin/cementum were removed and demineralized for 7 days at 55° C with 950 µl of EDTA (0.5 M, pH 8). This material was incubated at 55° C overnight to the cells suffer digestion of proteins and RNA by the action of 300 µl of Buffer ATL, 20 µl Proteinase K and 1 µl of RNAse. The final step was completed by the extraction kit Qiagen DNA Investigator (QIAGEN®). The efficiency of the extracted DNA was tested by amplification of a fragment of at least 362 base pairs (bp) of the mitochondrial DNA control region in four specimens of T. truncatus. A total of two haplotypes were defined from 11 polymorphic sites. The high polymorphism detected is a possible consequence of the great genetic variability of the genus Tursiops. In cases where there is the subspecies hypothesis based on morphological data, molecular identification can help to assign these museum specimens to each ecotypes, being extremely important the use of efficient and nondestructive extraction methods, as showed here, to obtain satisfactory results and to conserve the specimens.

This report summarizes the second year of a three-year effort in the western main Hawaiian Islands to study the residency patterns and spatial use of odontocetes in the Hawaii Range Complex. Surveys were made off Kaua‘i and Ni‘ihau over eighteen days in July/August 2011, during which time there were 65 encounters with five species of odontocetes. Twenty-four of those encounters were cued by acoustic detections from the Marine Mammal Monitoring on Navy Ranges (M3R) system from the Pacific Missile Range Facility, thus providing species verifications of the acoustic system. Additionally, 22645 photographs for individual and species identification, and forty-eight biopsy samples for genetic analyses, were collected. Some highlights of the field work include: the first ever satellite tag deployments on free-ranging rough-toothed dolphins, and the first satellite tag deployment in Hawaiian waters of a bottlenose dolphin; only the second encounter with killer whales in twelve years of surveys in Hawaiian waters; and encounters with a lone pantropical spotted dolphin, always in association with a group of spinner dolphins, as has been similarly documented in 2004 and 2005. The latter two highlights suggest, respectively, that there is no resident Hawaiian killer whale population, and that this particular (at least) pantropical spotted dolphin has a long-term association with spinner dolphins. The first highlight has provided the first unbiased movement and habitat use data for both rough-toothed and bottlenose dolphins in Hawaiian waters. N00244-10-1-0048

Biological samples of free-ranging dolphins are increasingly used to gain information on population structure and ecology. In small cetaceans, the gender of individuals usually cannot be determined at sea, and population sex ratio has to be inferred indirectly. We used molecular sexing to determine the gender of 340 biopsy samples of bottlenose dolphins, Tursiops truncatus, spotted dolphins, Stenella frontalis, and common dolphins, Delphinus delphis, collected around the Azores and Madeira. Sex ratio was globally skewed in favor of males, and differed between species and archipelagos. Skew was probably influenced by the selectivity of biopsy collectors and seasonal or year-round predominance of males in natural populations. Skew was also influenced by sampling duration and intensity. In the Azores, when several samples were successively collected within the same group, the proportion of female samples decreased as a function of sample order. This trend indicated a tendency for females to increasingly avoid the boat while samples were being collected. It showed that males and females reacted differently to the perturbation caused by the biopsy sampling process (i.e., sample collection and driving style).

Cres and Lošinj archipelago represents important feeding and breeding ground for the resident population of bottlenose dolphins (Tursiops truncatus). However, in the past decade, this area has been subjected to a strong development of nautical tourism that constitutes the primary source of the underwater anthropogenic noise over the low frequencies (below 1 kHz). This is especially due to the increased number and high mobility of the fast recreational vessels that colonize the area during the summer season. The aim of this study is to identify the critical areas in terms of noise and vessel presence and to correlate this anthropogenic pressure to bottlenose dolphin distribution within the archipelago. A long – term monitoring of Sea Ambient Noise was carried out on ten predefined acoustic locations in the period January 2005 – December 2008. Acoustic recordings have been made by using a RESON TC4032 hydrophone and Pioneer DC- 88 DAT recorder. Collected data has been analyzed with SPECTRA RTA software obtaining the 1/3 octave band analysis for each acoustic sample. Data on noise and vessel presence have been correlated with data on spatial distribution of bottlenose dolphins in the area collected over the same time span. Results indicate that critically noisy areas bear some relationship to the spatial and temporal distribution of bottlenose dolphins.