Tursiops truncatus

The social structure of coastal ecotype bottlenose dolphins, Tursiops truncatus, is largely unknown as they inhabit regions far from shore. This study reports on a community of bottlenose dolphins ! 27 km from Grand Bahama Island (May-September, 1993-2002). Resident and non-resident dolphins occurred in the area. Some dolphins traveled over 320 km between communities; others showed longterm site fidelity up to 17 yr. Average group size was 3-5, and was significantly larger with calves present and significantly smaller when traveling. The half-weight index was used to determine coefficients of association (COA) for individuals of known sex annually and for pooled years. Permutation tests revealed non-random associations and presence of preferred/avoided companions in all data sets. Annual COAs were low: female-female x ¼ 0.31, male-male x ¼ 0.30, and mixed-sex x ¼ 0.26. Mother-calf associations showed the highest values. Some males formed strong, long-term bonds. Female COAs fluctuated with reproductive status. Using pooled data, COAs were lower and the same basic trends were evident. However, strong associations seen in the annual data were not evident in pooled data. Bottlenose dolphins that inhabit offshore, shallow water show many of the same social structure characteristics as in well-studied coastal populations.

With four decades of data on a population of bottlenose dolphins (Tursiops truncatus) resident to Sarasota Bay (SB), The Sarasota Dolphin Research Program offers an unparalleled platform for ground-truthing stable isotope data and exploring bottlenose dolphin ecology in a natural setting. We explored carbon isotope value fidelity to habitat utilization by comparing delta13C data from whole teeth and muscle to

Amaç: 2007 - 2015 yılları arasında arazide karşılaşılan, hakkında kısıtlı da olsa veriler edinilen memelilere ilişkin bilginin paylaşılması mevcut çalışmanın amacını teşkil etmektedir. Bu veriler, fotoğraflar, kısmen düzenli olarak kaydedilmiş veriler ve kısa notlar olarak sunulmuştur. Bildiriye numaralandırılmış bir isim verilmesi sayesinde çalışmaların tekrarlı hale getirilmesi amaçlanmaktadır.
    Gereçler ve Yöntemler: Çalışma kapsamında, karşılaşılmış 9 memeli organizmanın (Sciurus vulgaris, Sus scrofa, Vulpes vulpes, Martes sp., Tursiops truncatus, bir Chiroptera üyesi, Erinaceus concolor, Lutra lutra ve Meles meles), 3 ilde (Aydın, Denizli ve Muğla) bulundukları yerler harita üzerinde gösterilmiş, karşılaşma tarihleri, koordinatları, bulunuş şekilleri ve birey sayıları kaydedilmiştir. Ayrıca her organizmaya ait görsellerle çalışma zenginleştirilmiştir. İhbarlarla gelen bilgiler sayesinde veriler desteklenmiştir. Aktif saha çalışmalarının gerçekleştirilmesinde hem profesyonel fotoğraf makinalarından hem de fotokapan kullanım yöntemlerinden yararlanılmıştır.
    Sonuç: Çalışmanın çıktıları değerlendirildiğinde, türlerin bulunuşlarının zorluğu dikkat çekmektedir. Ayrıca Meles meles gibi bazı türlerin ölü olarak bulunması gibi sorunların varlığı göze çarpmaktadır. Bu bakış açısı geliştirildiğinde, ülkemizde yapılacak kapsamlı mamalojik çalışmaların önemi ön plana çıkmaktadır. Bu çalışmalara ait sonuçların, söz konusu organizmalarla iç içe yaşam süren yöre insanları ile paylaşılması bilim insanlarının yükümlülüğüdür.

Objective-To develop robust reference intervals for hematologic and serum biochemical variables by use of data derived from free-ranging bottlenose dolphins (Tursiops truncatus) and examine potential variation in distributions of clinicopathologic values related to sampling sites' geographic locations. Animals-255 free-ranging bottlenose dolphins. Procedures-Data from samples collected during multiple bottlenose dolphin capturerelease projects conducted at 4 southeastern US coastal locations in 2000 through 2006 were combined to determine reference intervals for 52 clinicopathologic variables. A nonparametric bootstrap approach was applied to estimate 95th percentiles and associated 90% confidence intervals; the need for partitioning by length and sex classes was determined by testing for differences in estimated thresholds with a bootstrap method. When appropriate, quantile regression was used to determine continuous functions for 95th percentiles dependent on length. The proportion of out-of-range samples for all clinicopathologic measurements was examined for each geographic site, and multivariate ANOVA was applied to further explore variation in leukocyte subgroups. Results-A need for partitioning by length and sex classes was indicated for many clinicopathologic variables. For each geographic site, few significant deviations from expected number of out-of-range samples were detected. Although mean leukocyte counts did not vary among sites, differences in the mean counts for leukocyte subgroups were identified. Conclusions and Clinical Relevance-Although differences in the centrality of distributions for some variables were detected, the 95th percentiles estimated from the pooled data were robust and applicable across geographic sites. The derived reference intervals provide critical information for conducting bottlenose dolphin population health studies. (Am J Vet Res 2009;70:973-985) R eference intervals for hematologic and serum biochemical variables are important in assessments of animal health. Clinicopathologic test results for individual animals are compared with the distribution of

The significance of metal concentrations in marine mammals is not well understood and relating concentrations between stranded and free-ranging populations has been difficult. In order to predict liver concentrations in free-ranging dolphins, we examined concentrations of trace elements (Al, As, Ba, Be, Cd, Co, Cu, Fe, Li, Mn, Ni, Pb, Sb, Se, Sn, total Hg (THg), V, Zn) in skin and liver of stranded bottlenose dolphins (Tursiops truncatus) from the South Carolina (SC) coast and the Indian River Lagoon, Florida (FL) during 2000-2008. Significantly higher concentrations of Zn, Fe, Se, Al, Cu and THg were found in skin while liver exhibited significantly higher Cu, Fe, Mn and THg concentrations for both study sites. Mean skin concentrations of Cu and Mn were significantly higher in SC dolphins while higher concentrations of THg and V were found in FL dolphins. In addition, liver tissues in SC dolphins exhibited significantly higher As concentrations while higher Fe, Pb, Se, THg, and V levels were found in FL dolphins. Two elements (Cu and THg) showed significant age-related correlations with skin concentration while five elements (Cu, Se, THg, Zn and V) showed age-related correlations with liver concentrations. Geographic location influenced age-related accumulation of several trace elements and age-related accumulation of THg in hepatic tissue was observed for both sites to have the highest correlations (r 2 = 0.90SC; r 2 = 0.69FL). Mean THg concentration in liver was about 10 times higher in FL dolphins (330 lg g À1 dw) than those samples from SC dolphins (34.3 lg g À1 dw). The mean molar ratio of Hg to Se was 0.93 ± 0.32 and 1.08 ± 0.38 for SC and FL dolphins, respectively. However, the Hg:Se ratio varied with age as much lower ratios (0.2-0.4) were found in younger animals. Of the 18 measured elements, only THg was significantly correlated in skin and liver of stranded dolphins and skin of free-ranging dolphins from both sites suggesting that skin may be useful in predicting Hg concentrations in liver tissue of free-ranging dolphins. Results indicate that 33% of the stranded and 15% of the free-ranging dolphins from FL exceed the minimum 100 lg g À1 wet weight (ww) ($400 dw) Hg threshold for hepatic damage while none from SC reached this level. Hepatic concentrations of As in SC dolphins and V in FL dolphins were also highly correlated with skin concentrations which may have some regional specificity predictive value. The present study provides the first application of trace element concentrations derived from stranded bottlenose dolphins to predict liver concentrations in free-ranging populations.

Accurate identification of human-induced injuries that lead to death or interfere with reproduction is important for marine mammal management, as deaths exceeding established limits can lead to restrictions on fisheries or vessel operations. The fates of cetaceans last seen swimming with attached gear, particularly in pelagic fisheries, or with vessel strike lacerations, have been difficult to predict. Survival and reproduction data from long-term research on resident common bottlenose dolphins near Sarasota, Florida were examined relative to consequences of fishing gear ingestion, line entanglements, vessel strikes, and amputations of unknown origins. Fishing hooks embedded in the throat, goosebeak, or esophagus, or line wrapped around the goosebeak, generally lead to death. Multiple, constrictive line wraps around fin insertions can lead to amputation, blood loss, impaired mobility, or infection. Dolphins with ingested gear or severe entanglements may swim away with the gear, but likely die later. Propeller injuries involving only soft tissue were often survivable. Some dolphins survived amputations of the distal ends of fins, and continued to reproduce. As a precautionary approach, dolphins with ingested gear or severe constrictive entanglements should be considered mortalities, but extrapolations of findings from coastal bottlenose dolphins to other cetaceans and different gear must be done with caution.

A specific display observed during agonistic behavior among captive Atlantic bottlenosed dolphins (Tursiops truncatus) was examined. The primary component of the display was an open-mouthed posture accompanied by violent vertical head motions and the emission of pulse-type vocalizations. Jaw-clap behavior produced during the display was quantified for use as an index of aggressive motivation. By aurally monitoring the animals' vocalizations it was found that the level of aggressive response between the participants of the interactions increased with the production and subsequent duration of burst-pulse sounds. The possibility of burstpulse sounds resulting in auditory or tactile discomfort when directed toward conspecifics is discussed.

Previous studies have proposed that seagrass habitats, by supporting diverse and abundant fish assemblages, are preferred by foraging dolphins in coastal systems. To test this hypothesis, we (1) examined the fine-scale behavior of bottlenose dolphins in relatively pristine and developed inshore sites near Clearwater Harbor, Florida, USA, and (2) used an otter trawl to sample potential fish prey in non-seagrass and seagrass habitats. In the pristine site, dolphins preferred dredged channel and spoil-island habitats, while least preferring shallow seagrass habitats. In the developed site, foraging dolphins preferred the natural channel habitat, but exhibited little further selection. Therefore, the hypothesis that dolphins prefer seagrass habitats while foraging was rejected. Feeding frequency was significantly associated with diel state, with foraging peaking at dawn and decreasing throughout the day. Dolphin group size was negatively correlated and nearest neighbor distance positively correlated with feeding frequency. Analysis of trawl data focused on the pinfish Lagodon rhomboides which dominates the diets of dolphins in west Florida. The relative abundance of pinfish was significantly greater and standard lengths significantly less in seagrass than in non-seagrass habitats. Dolphins therefore forage in non-seagrass habitats where fish prey is both larger and perhaps more available. Although seagrass habitats support greater abundance of smaller fishes, they also provide a structural refuge which obscures fishes both visually and possibly acoustically. Thus, the importance of seagrasses to the health of coastal dolphins is probably indirect, as seagrasses support fish populations on which dolphins rely.

El grupo de los mamíferos marinos está constituido por tres órdenes: 1) los cetáceos, que a la vez se subdividen en odontocetos (ballenas con dientes) que son los delfines y marsopas, y los misticetos (ballenas verdaderas o con barbas), que son las ballenas; 2) los sirenios, que son los manatíes y los dugongos (especie parecida al manatí, que habita en las aguas poco profundas del Indo-Pacífico), y 3) los carnívoros, que incluyen las nutrias, osos polares y el suborden de los pinnípedos que son las focas, los lobos marinos y las morsas.

México cuenta con 3.8 millones de kilómetros cuadrados de mares patrimoniales (Semar, 2008), en los cuales se encuentra una gran diversidad de especies de mamíferos marinos. De las 121 especies que existen en todo el mundo, en nuestros mares podemos encontrar aproximadamente 46 especies, incluyendo ocho de misticetos (Aurioles-Gamboa, 1995), lo cual representa el 61 % de todas las especies que existen en el mundo. Incluso, una especie de marsopa, la vaquita marina (Phocoena sinus), es endémica de nuestro país.

Cabe destacar que para el Golfo de México, por lo menos en la parte mexicana y en particular para el estado de Veracruz, los cetáceos prácticamente no han sido estudiados. En contraste, para los manatíes sí se han hecho varios estudios, aunque la mayoría de éstos se han llevado a cabo en el Caribe mexicano, específicamente en las costas de Chetumal.

Man-made endocrine-disrupting chemicals (EDCs) range across all continents and oceans. Some geographic areas are potentially more threatened than others: one of these is the Mediterranean Sea. Levels of some xenobiotics are much higher here than in other seas and oceans. In this paper we review the final results of a project supported by the Italian Ministry of the Environment, in

Whistles are narrowband, frequency-modulated sounds produced by many cetaceans. Whistles are extensively studied in delphinids, where several factors have been proposed to explain between-and within-species variation. We examined factors associated with geographic variation in whistles of common bottlenose dolphins (Tursiops truncatus) by assessing the role of ambient noise, noise from boats, and sympatry with other dolphin species, and reviewing and comparing whistle structure across populations in the western and eastern Atlantic Ocean. Whistles of adjacent populations differed, particularly in frequency parameters. A combination of factors may contribute to microgeographic whistle variation, including differences in ambient noise levels (dolphins produced relatively higher frequency whistles in the noisiest habitat), and differences in number of boats present (when multiple boats were present, dolphins whistled with greater frequency modulation and whistles were higher in maximum frequency and longer than when a single boat was present). Whistles produced by adjacent populations were relatively similar in structure. However, for clearly separated populations, the distance between them did not relate directly to whistle structure. We propose that plasticity in bottlenose dolphin whistles facilitates adaptation to local and changing conditions of their habitat, thus promoting variation between populations at different geographic scales.

There is a need for biological information to support current stock designations of bottlenose dolphins (Tursiops truncatus) in the Gulf of Mexico. The existence of many inshore, resident “communities” raises questions as to the relationship these dolphins may hold with dolphins inhabiting neighboring inshore and coastal areas. In this study, population subdivision was examined among four resident, inshore bottlenose dolphin stocks (Sarasota Bay, FL, Tampa Bay, FL, Charlotte Harbor, FL and Matagorda Bay, TX) and one coastal stock (1–12 km offshore) in the Gulf of Mexico. Evidence of significant population structure among all areas was found on the basis of both mitochondrial DNA (mtDNA) control region sequence data and nine nuclear microsatellite loci. Estimates of relatedness showed no population contained a significantly high number of related individuals, while separate AMOVAs for males and females indicated that both sexes exhibit a significant level of site philopatry. Results presented here provide the first genetic evidence of population subdivision between the coastal Gulf of Mexico and adjacent inshore areas along the central west coast of Florida. Such strong genetic subdivision is surprising given the short geographical distance between many of these areas and the lack of obvious geographic barriers to prevent gene flow. These findings support the current, separate identification of stocks for bottlenose dolphins inhabiting the eastern coastal and inshore areas of the Gulf of Mexico.

... Adam M. Schaefer,1 John S. Reif,2 Juli D. Goldstein,1 Caitlin N. Ryan,1 Patricia A. Fair,3 and Gregory D. Bossart1 ... Venezuelan equine encephalitis virus; West Nile virus; C. psittaci; and T. gondiiin dolphins in the Indian River Lagoon, Florida, and the estua-rine waters around ...

Over the last decade there has been considerable growth in marine mammal-watching tourism throughout the world. Due to the species use of coastal habitats, bottlenose dolphins are most frequently exposed to dolphin-watching tourism. We conducted boatbased focal follows of schools of bottlenose dolphins to determine the effect of boats on dolphin behaviour. A CATMOD analysis showed that behaviour differed by boat number, in particular, resting behaviour decreased as boat number increased. Dolphins rested less and engaged in more milling behaviour in the presence of permitted dolphin-watching boats compared to non-permitted boats. An increase from 49 to 70 permitted trips per week and a change in their departure times resulted in a further decrease in resting behaviour. Currently the effects of boats, in particular permitted boats, on dolphin resting behaviour whilst they are in the Bay of Islands, are substantial. In the light of these findings we suggest that current legislation in New Zealand is not affording this isolated population protection from disturbance. #

The cetaceans of Ghana and the Gulf of Guinea have, until recently, remained unstudied. Periodical monitoring of artisanal fisheries for bycatches in seven Ghanaian artisanal fishing ports and landing sites over 1996-2004 has provided photographic and specimen evidence to validate occurrence of 18 species (17 odontocetes, 1 mysticete) in a tropical, predominantly pelagic cetacean fauna. At least nine species and subspecies had not previously been documented for Ghana (with asterisk), and four species are authenticated for the first time in the Gulf of Guinea (double asterisk), i.e.

1Bottlenose dolphins Tursiops truncatus are amongst the best-known cetaceans. In the Mediterranean Sea, however, modern field studies of cetaceans did not start until the late 1980s. Bottlenose dolphins have been studied only in relatively small portions of the basin, and wide areas remain largely unexplored.2This paper reviews the ecology, behaviour, interactions with fisheries and conservation status of Mediterranean bottlenose dolphins, and identifies threats likely to have affected them in historical and recent times.3Whilst intentional killing was probably the most important cause of mortality until the 1960s, important ongoing threats include incidental mortality in fishing gear and the reduced availability of key prey caused by overfishing and environmental degradation throughout the region. Additional potential or likely threats include the toxic effects of xenobiotic chemicals, epizootic outbreaks, direct disturbance from boating and shipping, noise, and the consequences of climate change.4The flexible social organization and opportunistic diet and behaviour of bottlenose dolphins may allow them to withstand at least some of the effects of overfishing and habitat degradation. However, dolphin abundance is thought to have declined considerably in the region and management measures are needed to prevent further decline.5Management strategies that could benefit bottlenose dolphins, such as sustainable fishing, curbing marine pollution and protecting biodiversity, are already embedded in legislation and treaties. Compliance with those existing commitments and obligations should be given high priority.Bottlenose dolphins Tursiops truncatus are amongst the best-known cetaceans. In the Mediterranean Sea, however, modern field studies of cetaceans did not start until the late 1980s. Bottlenose dolphins have been studied only in relatively small portions of the basin, and wide areas remain largely unexplored.This paper reviews the ecology, behaviour, interactions with fisheries and conservation status of Mediterranean bottlenose dolphins, and identifies threats likely to have affected them in historical and recent times.Whilst intentional killing was probably the most important cause of mortality until the 1960s, important ongoing threats include incidental mortality in fishing gear and the reduced availability of key prey caused by overfishing and environmental degradation throughout the region. Additional potential or likely threats include the toxic effects of xenobiotic chemicals, epizootic outbreaks, direct disturbance from boating and shipping, noise, and the consequences of climate change.The flexible social organization and opportunistic diet and behaviour of bottlenose dolphins may allow them to withstand at least some of the effects of overfishing and habitat degradation. However, dolphin abundance is thought to have declined considerably in the region and management measures are needed to prevent further decline.Management strategies that could benefit bottlenose dolphins, such as sustainable fishing, curbing marine pollution and protecting biodiversity, are already embedded in legislation and treaties. Compliance with those existing commitments and obligations should be given high priority.

Skull morphometry of 206 stranded juvenile and adult bottlenose dolphins (Tursiops truncatus) from Texas and Florida were examined. Juveniles differed significantly from adults in both Texas and Florida populations. Sexual dimorphism was present in skulls from Texas but not from Florida. Regional differences in females from Texas and Florida were apparent, especially in braincase height, whereas male bottlenose dolphins did not differ between regions. Females could be distinguished accurately to region (90% classification success) using skull morphometry. Cranial morphometrics of T. truncatus are concrete values that may aid in identification of a type specimen for each population. Furthermore, these results can be used as a standard for Tursiops in the Gulf of Mexico.

In April -June, 2002 and 2003, the cetacean bycatch was studied in the bottom gillnet fishery for turbot on the western coast of the Turkish Black Sea. The aim of the study was to gather information about the amount of the cetacean bycatch so that the conservation of the cetacean species in the Black Sea could be effectively managed.

Research initiated in 1970 has identified a long-term, year-round resident community of about 140 bottlenose dolphins (Tursiops truncatus) in Sarasota Bay, Florida, providing unparalleled opportunities to investigate relationships between organochlorine contaminant residues and life-history and reproductive parameters. Many individual dolphins are identifiable and of known age, sex, and maternal lineage (V4 generations). Observational monitoring provides data on dolphin spatial and temporal occurrence, births and fates of calves, and birth-order. Capture-release operations conducted for veterinary examinations provide biological data and samples for life-history and contaminant residue measurement. Organochlorine concentrations in blubber and blood (plasma) can be examined relative to age, sex, lipid content, and birth-order. Reproductive success is evaluated through tracking of individual female lifetime calving success.

Alliances between reproductive males have been described in both cetacean and terrestrial mammal societies, and kin selection theory has often been invoked to explain these stable male coalitions. However, recent studies of bottlenose dolphins, Tursiops aduncus, in Australia suggest that mechanisms other than kinship are fundamental in the formation of male alliances. We supplemented skin biopsy sampling with the collection of faecal samples from individually recognized wild bottlenose dolphins, T. truncatus, to assess the role of kin selection in alliance membership in the northeast Bahamas. Stable alliances between pairs of males were identified based on association analyses of individual photoidentification data collected over 4 years. Molecular genetic analyses of tissue samples revealed highly significant correlations between patterns of association and both mitochondrial DNA haplotype identity and microsatellite relatedness, indicating that males within long-term alliances are more closely related than expected by chance. These data reinforce the high degree of plasticity previously reported within the genus Tursiops, and suggest that social and ecological differences between populations can markedly affect the role of kin selection in determining social alliances between male bottlenose dolphins.

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).

The authors tested whether the understanding by dolphins (Tursiops truncatus) of human pointing and head-gazing cues extends to knowing the identity of an indicated object as well as its location. In Experiment 1, the dolphins Phoenix and Akeakamai processed the identity of a cued object (of 2 that were present), as shown by their success in selecting a matching object from among 2 alternatives remotely located. Phoenix was errorless on first trials in this task. In Experiment 2, Phoenix reliably responded to a cued object in alternate ways, either by matching it or by acting directly on it, with each type of response signaled by a distinct gestural command given after the indicative cue. She never confused matching and acting. In Experiment 3, Akeakamai was able to process the geometry of pointing cues (but not head-gazing cues), as revealed by her errorless responses to either a proximal or distal object simultaneously present, when each object was indicated only by the angle at which the informant pointed. The overall results establish that these dolphins could identify, through indicative cues alone, what a human is attending to as well as where.

The amount of published data about cetaceans recorded on coastal waters of northern Chile is limited. Here we compiled 35 sightings of seven cetacean species obtained from 150 km2 waters around Isla Chañaral (29°01'S - 71°37' O), Humboldt Penguin National Reserve (HPNR), between 1988 and 1995. We sighted Ba/aenoptera physalus, B. acutorostrata, Megaptera novaeangliae, Orcinus orca, Tursiops truncatus, Globicephala meas

It has been suggested that seamounts hold higher abundances of some 'visiting' animals, such as tuna, sharks, billfishes, marine mammals, sea-turtles and even seabirds, but this has been based on sparse records, and warrants further examination. In this paper we use data from a fishery observer program to examine whether the predicted higher abundances of tuna, marine mammals, sea turtles and seabirds actually occur around Azores seamounts and to map the distribution of the various species. Our results indicate that some marine predators (skipjack Katsuwonus pelamis and bigeye tuna Thunnus obesus, common dolphin Delphinus delphis and Cory's shearwater Calonectris diomedea borealis) were significantly more abundant in the vicinity of some shallowwater seamount summits. Our methodology, however, failed to demonstrate a seamount association for bottlenose dolphins Tursiops truncatus, spotted dolphin Stenella frontalis, sperm whale Physeter macrocephalus, terns Sterna hirundo and S. dougalli, yellow-legged gull Larus cachinnans atlantis and loggerhead sea turtles Caretta caretta. Seamounts may act as feeding stations for some of these visitors. Not all seamounts, however, seemed to be equally important for these associations. Only seamounts shallower than 400 m depth showed significant aggregation effects. These seamounts may be considered hotspots of marine life in the Azores, and a special effort should be made in order to ensure a sustainable management of these habitats.

1.Nine cetacean species have been reliably reported to occur in the shallow northern Adriatic Sea since the 17th century. However, only two species were considered regular there until the 1970s: the short-beaked common dolphin (Delphinus delphis) and the common bottlenose dolphin (Tursiops truncatus).2.Short-beaked common dolphins have progressively disappeared from the northern Adriatic and are now rare in the region. The systematic culling campaigns and other takes that occurred between the second half of the 18th century and the 1960s, and habitat degradation in subsequent years are the most likely causes of their decline.3.Today, common bottlenose dolphins are the only regular component of the northern Adriatic cetacean fauna; however, they now occur at low densities, and their fragmented groups are facing significant anthropogenic threats.4.The future of northern Adriatic dolphins will depend on precautionary action to prevent further decline and on intensified research effort aimed at identifying the most effective mitigation strategies. Copyright © 2004 John Wiley & Sons, Ltd.Nine cetacean species have been reliably reported to occur in the shallow northern Adriatic Sea since the 17th century. However, only two species were considered regular there until the 1970s: the short-beaked common dolphin (Delphinus delphis) and the common bottlenose dolphin (Tursiops truncatus).Short-beaked common dolphins have progressively disappeared from the northern Adriatic and are now rare in the region. The systematic culling campaigns and other takes that occurred between the second half of the 18th century and the 1960s, and habitat degradation in subsequent years are the most likely causes of their decline.Today, common bottlenose dolphins are the only regular component of the northern Adriatic cetacean fauna; however, they now occur at low densities, and their fragmented groups are facing significant anthropogenic threats.The future of northern Adriatic dolphins will depend on precautionary action to prevent further decline and on intensified research effort aimed at identifying the most effective mitigation strategies.

Papers Papers Infection with Brucella ceti and high levels of polychlorinated biphenyls in bottlenose dolphins (Tursiops truncatus) stranded in south-west England Eight bottlenose dolphins (Tursiops truncatus) that stranded in Cornwall, south-west England, between June 2004 and December 2007 were examined using standardised postmortem examination and bacteriological methods. Evidence of Brucella species infection was found in four of these dolphins on culture. In addition, of the eight dolphins, four were positive and two were weakly positive for antibodies to Brucella species on serological analyses of pericardial and other fluids using a competitive ELISA and two indirect ELISAs. High or very high levels of the sum of 25 individual chlorobiphenyl congeners (∑25CBs) were also determined in blubber samples from two of the dolphins (45.5 and 446.6 mg/kg lipid weight). Brucella species were first reported in marine mammals in the UK in Scotland in 1994 (Ross and others 1994). Subsequently, evidence of Brucella infection in marine mammals has been reported in many species globally since the early 1990s (Ewalt and others 1994, Jepson and others 1997, Dawson 2005, Tachibana and others 2006, Aguirre and others 2007, Ohishi and others 2007). The first isolation of Brucella species from marine mammals off the coast of Cornwall, UK, was recorded in 1998 from the liver of a by-caught harbour porpoise (Phocoena phocoena) (Dawson and others 2004). In 2007, the name Brucella ceti was proposed for Brucella strains isolated from cetaceans, and Brucella pinnipedialis for strains isolated from pinnipeds (Foster and others 2007).

The objectives of this study were to validate a relaxin and progesterone RIA for use in bottlenose dolphins, and quantify and characterize both hormones in extracts of placental tissue and serum collected during pregnancy and the post-partum period, and compare the results between dolphins with live and stillborn calves. In Experiment 1, validation of a heterologous relaxin and progesterone RIA involved specific displacement of antibody-bound radiolabeled human relaxin or progesterone in response to increasing volumes of pooled pregnant dolphin serum and amounts of respective hormone standards added to a fixed volume of serum. The displacement curves were considered parallel and additive relative to respective standard curves. In Experiment 2, immunoreactive relaxin and progesterone were detected in placental extracts and, in corresponding serum samples, concentrations of both hormones were higher during the pre-partum than post-partum periods. Circulatory concentrations of progesterone decreased (P < 0.05) from relatively high concentrations during early and mid-pregnancy to intermediate concentrations by late pregnancy (month effect, P < 0.0001) in dolphins with live births, whereas, in dolphins with stillbirths, the decrease in progesterone began earlier (month-by-birth status interaction, P < 0.007); mean concentrations were lower at mid-(37%, P < 0.06) and late (25%) pregnancy. Temporally, relaxin increased (P < 0.05) progressively from relatively low concentrations during early pregnancy to high concentrations during late pregnancy (month effect, P < 0.0001) and was not different between birth statuses (birth status effect, P = 0.76; month-by-birth status interaction, P = 0.17). Even though the interaction did not reach significance, mean relaxin concentrations were 42%, 29%, and 34% lower at early, mid-, and late pregnancy, respectively, in dolphins with stillbirths than in those with live births. In conclusion, the pregnancy-specific increase in serum concentrations of relaxin and lower concentrations of both relaxin and progesterone in association with stillbirths suggest the potential for relaxin to be used diagnostically to determine pregnancy status, and one or both hormones to be used to assess placental function, and, perhaps, fetal well-being in bottlenose dolphins and other cetaceans.

Odontocetes use active sonar for echolocation, navigation and socialisation. Their sonar is characterised by narrow transmission and reception directivity patterns, over a variety of ranges and frequencies. Typical echolocation clicks of bottlenose dolphins (Tursiops truncatus) last between 50-200 μs, with a broad frequency range of ~100-170 kHz depending on circumstances. These characteristics are very attractive for the design of bio-inspired sonars, but the actual mechanisms of sound reception are not well understood. Physiological and behavioural evidence suggests that dolphins hear the echoes of their high-frequency clicks through their lower jaws. The angular precision predicted by this theory is however much less than dolphins have been observed to display. A recent hypothesis is that the teeth also play a part in sound reception, acting as a passive beam-forming structure. This paper presents 2-D models of acoustic propagation in a dolphin jaw, based on real measurements, and shows the importance of multiple scattering between teeth, potential masking effects, and the match between theoretical directivity and that observed in the field. We use these results to look at the implications for realistic biosonar design.

We succinctly review and document new cases of diseases of the skin and the skeletal system and external traumata in cetaceans from Ecuador, Colombia, Peru, Chile, Argentina, Uruguay, Brazil, and Venezuela. The survey revealed 590 cases diagnosed with a significant pathology, injury or malformation on a total of 7635 specimens of 12 odontocete species examined or observed in 1984-2007. Tattoo skin disease (TSD), lobomycosis-like disease (LLD) and cutaneous diseases of unknown aetiology seem to be emerging in several populations. TSD was confirmed in eight species from the SE Pacific and SW Atlantic. LLD affected only inshore Tursiops truncatus but was found in four tropical countries, namely Colombia, Ecuador, Peru and Brazil. Lobomycosis was confirmed by histology in one male from the Tramandaí estuary, southern Brazil. All LLD-affected specimens were encountered in the vicinity of major ports and cities and a possible association with chemical or organic water pollution is suspected. Whitish velvety cutaneous marks associated with scars occurred in inshore T. truncatus, Sotalia guianensis and Pseudorca crassidens. Large, rounded lesions were seen in a Cephalorhynchus eutropia calf and a C. commersonii. Cutaneous wounds and scars as well as body traumata possibly related to net entanglements and boat collisions were observed in 73 delphinids and Phocoena spinipinnis. Traumatic injuries resulted in the partial or complete amputation and other disfiguring scars of appendages in 17 cases. Fractures of the skull, ribs and vertebrae thought to be caused by fisheries-related interactions or boat collisions were seen in single individuals of Delphinus capensis, Lagenorhynchus obscurus, T. truncatus, S. guianensis and Ziphius cavirostris. Prevalence of osteopathology in small cetaceans from Peru, Brazil and Venezuela ranged widely, from 5.4% to 69.1%. In four species from Peru, lytic cranial lesions were the most frequently observed disease (5.4%-42.9%), followed by hyperostosis and ankylosing spondylitis in offshore (31%, n=42) and inshore (15.4%, n=26) T. truncatus. Fractures and other bone traumata were present in 47.2% of 53 axial skeletons of S. guianensis from the northern Rio de Janeiro state (Brazil) in 1987-1998. A high prevalence (48.4%, n=31) of, apparently congenital, malformations of cervical vertebrae, observed in a 2001-2006 sample, may be explained by a hypothetical genetic bottleneck in this population. Malformations with deficient ossification would clearly increase susceptibility for fractures. This study demonstrates the utility of a continent-wide analysis to discern epizootiological trends more readily than any local study could provide. Secondly, it underscores the need for focussed research on the effects of human activities on the spread of diseases in cetaceans, particularly in near-shore populations that utilize highly degraded coastal habitats.

Resumen. Con la fi nalidad de conocer las especies de mamíferos marinos que se encuentran en la costa central de Oaxaca, se elaboró un listado comentando las características de los registros obtenidos. Se incluyeron las observaciones hechas a lo largo de 30 recorridos por mar, entre junio de 1999 y enero de 2004, realizadas entre las bahías de Huatulco y la playa de La Escobilla. Adicionalmente se incluyeron registros de animales varados, así como observaciones realizadas desde la costa. Se presentan comentarios sobre el registro de 8 especies en la zona, incluyendo las localidades y fechas de los avistamientos. Stenella attenuata es la especie más abundante, y la zona de Zipolite-Isla Roca Blanca la localidad con el mayor número de avistamientos. Dado el crecimiento turístico del lugar, es importante contar con este tipo de registros ya que es poco lo que se sabe sobre estas especies en esta porción de la costa oaxaqueña.

Nineteen species of cetaceans (families Balaenopteridae, Kogiidae, Physeteridae, Ziphiidae and Delphinidae) occur in the Costa Rican Pacific Exclusive Economic Zone (EEZ). Based on data recorded from the EEZ by the Southwest Fisheries Service Center, Cascadia Research Collective, and CIMAR between 1979-2001, we mapped the distribution of 18 cetacean species. Our results suggest that the majority of the cetacean species use primarily oceanic waters, particularly those species within the families Balaenopteridae, Kogiidae. Physeteridae and Ziphiidae. Members of the family Delphinidae showed a wide variety of distribution patterns: seven species are widespread throughout the EEZ, four appear to be exclusively pelagic, and two are primarily coastal. Overall, three cetacean species appear to have populations concentrated in coastal waters: Stenella attenuata graffmani. Tursiops truncatus, and Megaptera novaeangliae. These three may be more susceptible to human activities due to the overl...

A widespread problem in the study of animal vocalizations is evaluating the acoustic similarity of signals both between individuals of a social group and between social groups. This problem becomes especially salient when classifying the narrow-band frequency-modulated signals, such as whistles, found in many avian and mammalian species. Whistles are usually characterized by their relative change in frequency over time, known as whistle ‘contour’. Measuring such a characteristic is difficult as it is not a single measurement, such as the mean frequency or duration of a signal, but several associated measurements of frequency across time. This paper reports on a new quantitative technique for determining whistle types based on whistle contour similarity and an application of this technique to the whistles of bottlenose dolphins to demonstrate its utility. This ‘contour similarity’ technique (CS technique) uses cluster analysis to group the correlation coefficients of frequency measurements from a data set of signals. To demonstrate the efficacy of this CS technique, three data sets were analysed, two using computer-generated signals and a third using adult bottlenose dolphin whistles, to (1) examine the efficacy of correlation coefficients for grouping signals by their similarity in whistle contour and (2) determine the viability of this technique for categorizing bottlenose dolphin whistles. Measured actual frequencies and correlation matrices from the four simulated signal types and a correlation matrix from the whistles of five captive adult bottlenose dolphins were each subjected to K-means cluster analysis and the resulting signal types were evaluated. Results indicated that the technique grouped actual frequencies according to the amount of shared actual frequencies and grouped correlation coefficients successfully according to signal contour. This result endured even if contours differed in overall duration or actual frequency or were expanded or compressed with respect to frequency or time. The results suggest that this approach is a viable method for assigning whistle contours to categories in bottlenose dolphins or any other species with narrow-band, frequency-modulated signals.

Data collected from wild and captive bottlenose dolphins, Tursiops truncatus, over the past five decades indicate that they produce individually distinctive signature whistles that function in individual recognition and in maintaining group cohesion. However, a recent study by failed to detect signature whistles in nine of 12 captive bottlenose dolphins. These authors suggested that previous studies of signature whistles had used biased data sets, and claimed that the visual classification methods used by most researchers were inferior to their computerized technique. To evaluate their claims, we randomly selected 20 whistles from each of 20 bottlenose dolphins from recordings made during brief captureerelease events in Sarasota Bay, FL, U.S.A., and asked 10 judges to visually group spectrograms based on similarity of their contours. Judges consistently grouped whistles according to the identity of the vocalizer; the mean number of whistles of a single dolphin in the judges' groups was 18.9 AE 1.6 out of 20 possible; resampling simulations indicate that it is highly unlikely (P < 0.0001) for this many whistles to be grouped together randomly. In contrast, the McCowan method was highly inaccurate at classifying whistles according to the identity of the vocalizer; whistles produced by multiple dolphins were grouped together. This study provides strong external validation for the reliability of visual classification of whistles, and confirms the presence of individually distinctive signature whistles in the vocal repertoire of bottlenose dolphins.

Polychlorinated biphenyls (PCBs) and chlorinated pesticides: dichlorodiphenyltrichloroethane and its metabolites (DDTs), chlordanes (CHLs), dieldrin, and hexaclorobenzene (HCB) were detected in the blubber and liver of 11 bottlenose dolphins (Tursiops truncatus) from the Canary Islands (North Atlantic Ocean). Samples were obtained from stranded dolphins over the period 1997–2005. Among the organochlorines analyzed, PCBs and DDTs were predominant in the two tissues, followed in decreasing order by chlordane, trans-nonachlor > cis-nonachlor > dieldrin and HCB. The sum 11 PCBs in the blubber ranged between 301 and 33,212 ng g−1 ww (990 and 136,679 ng g−1 lw). Highly chlorinated PCBs such us CB153, CB180, and CB138 were the prominent congeners, accounting for 51% of the total PCBs. The sum DDT concentration in the blubber ranged between 147 and 21,050 ng g−1 ww. (490–105,250 ng g−1 lw) The main DDT metabolite was p,p′-DDE, representing 83% of DDTs in the blubber. In general, the levels of PCBs and DDTs detected were similar to those found in bottlenose dolphins in the North of Europe. The 2,3,7,8-TCDD toxic equivalent (TEQ) in blubber and liver was calculated for the toxicity assessment of mono-ortho substituted PCBs congeners (CB105, CB118, CB156). It is important to mention that TEQ values and p,p′-DDE concentration in adult male specimens are approaching the levels associated with adverse effects found in marine mammals. The information provided represents the first tissue loads of organochlorine compounds in small cetaceans from this area. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2008.

Infanticidal behavior (i.e., the intentional killing of young) is common in the animal kingdom. Common bottlenose dolphins (Tursiops truncatus) engage extensively in intraspecific agonistic behaviors, and infanticidal behavior has been documented in many dolphin populations. However, these behaviors remain poorly understood in dolphins as descriptions of these events remain rare. Here, we report on an event involving agonistic intraspecific behavior of multiple bottlenose dolphins directed towards of a young calf at Turneffe Atoll, Belize. Boat-based surface observations, brief surface video, and photo analysis were used to identify individual dolphins. All dolphins were confirmed as part-time and long-term residents by matching dorsal fins to the long-term photo-ID catalog of local dolphins. Multiple dolphins displayed agonistic and likely injurious behavior towards the calf, including ramming and flipping it into the air and forcefully submerging it. Vocalizations recorded in surface video (whistles and burst-pulses) coincided with calf surface times. The repetition of a downsweeping contour was possibly associated with its distress.

An adult, female bottlenose dolphin (Tursiops trucncatus) was radio tagged and monitored via satellite-based Argos receivers for 25 d from 28 June to 23 July 1990, in Tampa Bay, Florida. A total of 794 transmissions were obtained during 106 satellite passes. A mean of 3.9 (SE = 0.24) locations/day were determined by Service Argos and showed the animal remained in the bay, usually close to the southeastern shore. The dolphin moved at least 58 1 km at a minimum mean speed of 1.2 (SE = 0.1) km/h. Data from 63,922 dives were recorded. The animal spent an average of 87.1 (SE = 0.6)% of the time submerged, with a mean dive duration of 2 5.8 (SE = 0.5) sec. Mean dive duration differed significantly between four periods of the day, as did the mean percent of time spent submerged. During the early morning the animal spent more time at the surface, averaged shorter dives, and was submerged less than other times of da:y. This is the first study to demonstrate die1 dive cycles in a bottlenose dolphin. Four months after tag loss, the dolphin was photographed with no evidence of necrosis or disfigurement of the dorsal fin. Satellite telemetry was demonstrated 452 Help Volumes Main Menu MATE ET AL.: SATELLITE-MONITORED MOVEMENTS 453