Data analysis model selection for estimating local population size of the Risso’s dolphin (Grampus griseus) in the Azores

27th Annual Conference of the European Cetacean Society. Setúbal, Portugal, 8-10 April 2013.

The Environmental History of Cetaceans in Portugal: Ten Centuries of Whale and Dolphin Records

The history between cetaceans and humans is documented throughout time not only in reports, descriptions, and tales but also in legal documents, laws and regulations, and tithes. This wealth of information comes from the easy spotting and identification of individuals due to their large size, surface breathing, and conspicuous above water behaviour. This work is based on historical sources and accounts accounting for cetacean presence for the period between the 12th and 17th centuries, as well as scientific articles, newspapers, illustrations, maps, non-published scientific reports, and other grey literature from the 18th century onwards. Information on whale use in Portugal's mainland has been found since as early as the 12th century and has continued to be created throughout time. No certainty can be given for medieval and earlier events, but both scavenging of stranded whales or use of captured ones may have happened. There is an increasing number of accounts of sighted, stranded, used, or captured cetaceans throughout centuries which is clearly associated with a growing effort towards the study of these animals. Scientific Latin species denominations only started to be registered from the 18th century onwards, as a consequence of the evolution of natural sciences in Portugal and increasing interest from zoologists. After the 19th century, a larger number of observations were recorded, and from the 20th century to the present day, regular scientific records have been collected. Research on the environmental history of cetaceans in Portugal shows a several-centuries-old exploitation of whales and dolphins, as resources mainly for human consumption, followed in later centuries by descriptions of natural history documenting strandings and at sea encounters. Most cetaceans species currently thought to be present in Portuguese mainland waters were at some point historically recorded.

Prey consumed by Guiana dolphin Sotalia guianensis (Cetacea, Delphinidae) and franciscana dolphin Pontoporia blainvillei (Cetacea, Pontoporiidae) in an estuarine environment in southern Brazil

The present study provides information about the diet of sympatric populations of small cetaceans in the Babitonga Bay estuary. This is the first study on the diet of these species in direct sympatry. The stomach contents of seven Guiana dolphins Sotalia guianensis and eight franciscanas Pontoporia blainvillei were analyzed. The prey of both cetaceans was mostly teleost fishes, followed by cephalopods. We identified 13 teleost fishes as part of the diet of the franciscanas, and 20 as part of the diet of Guiana dolphins. Lolliguncula brevis was the only cephalopod recorded, and was the most important prey for both cetaceans. Stellifer rastrifer and Gobionellus oceanicus were also important for franciscana, so as Mugil curema and Micropogonias furnieri were important for Guiana dolphins. Stellifer rastrifer and Cetengraulis edentulus were the fishes with the highest frequency of occurrence for franciscana (50%), while Achirus lineatus, C. edentulus, S. brasiliensis, Cynoscion leiarchus, M. furnieri, M. curema, Diapterus rhombeus, Eugerres brasilianus and G. oceanicus showed 28.6% of frequency of occurrence for Guiana dolphins. Franciscanas captured greater cephalopods than the Guiana dolphins in both total length (z= -3.38; n= 40; p< 0.05) and biomass (z = -2.46; n = 40; p<0.05). All of the prey species identified occur inside the estuary, which represents a safe habitat against predators and food availability, reinforcing the importance of the Babitonga Bay for these cetacean populations.

Efficiency of wear and decalcification technique for estimating the age of estuarine dolphin Sotalia guianensis

Most techniques used for estimating the age of Sotalia guianensis (van B,n,den, 1864) (Cetacea; Delphinidae) are very expensive, and require sophisticated equipment for preparing histological sections of teeth. The objective of this study was to test a more affordable and much simpler method, involving of the manual wear of teeth followed by decalcification and observation under a stereomicroscope. This technique has been employed successfully with larger species of Odontoceti. Twenty-six specimens were selected, and one tooth of each specimen was worn and demineralized for growth layers reading. Growth layers were evidenced in all specimens; however, in 4 of the 26 teeth, not all the layers could be clearly observed. In these teeth, there was a significant decrease of growth layer group thickness, thus hindering the layers count. The juxtaposition of layers hindered the reading of larger numbers of layers by the wear and decalcification technique. Analysis of more than 17 layers in a single tooth proved inconclusive. The method applied here proved to be efficient in estimating the age of Sotalia guianensis individuals younger than 18 years. This method could simplify the study of the age structure of the overall population, and allows the use of the more expensive methodologies to be confined to more specific studies of older specimens. It also enables the classification of the calf, young and adult classes, which is important for general population studies.

Isolation and characterization of microsatellite DNA markers for spinner dolphin (Stenella longirostris)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

EVIDENCE of A FAILED PREDATION ATTEMPT on A GUIANA DOLPHIN, Sotalia guianensis, BY A BULL SHARK, Carcharhinus leucas, IN BRAZILIAN WATERS.

Even though shark-cetacean interactions have been the subject of numerous studies worldwide, several ecological aspects such as competition, predation risk and co-evolution remain unclear. on February 16th, 2008, during a photo-identification survey to investigate population parameters of Guiana dolphins, Sotalia guianensis, in estuarine waters of Parana State (25[degree]S; 48[degree]W), Brazil, an adult dolphin was photographed without its dorsal fin. A detailed analysis of the healed area on the injured dolphin showed that the circular, crescent-shaped outlined wound was provoked by the bite of a bull shark, Carcharhinus leucas. Wound shape, prey-predator distributional patterns (sympatry) and feeding habits of the shark species here considered were indicative of the species' identity. The wound is likely to be the result of a failed predation attempt. Interactions between C. leucas and S. guianensis should be expected, since they are sympatric along almost all of their distribution range in the tropical and subtropical western South Atlantic. The presented observation adds S. guianensis to the list of cetacean species involved in interactions with large coastal predatory sharks.

Contamination by chlorinated pesticides, PCBs and PBDEs in Atlantic spotted dolphin (Stenella frontalis) in western South Atlantic

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Feeding habits of the atlantic spotted dolphin, Stenella frontalis, in southeastern Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo comparativo de dois programas de computador (Dolphin Imaging e Nemotec) versus o método manual utilizados para análises cefalométricas de pacientes com deformidade dento-facial padrão II

A-Nperp, Pg-Nperp e mandibular plane). Thirty patients (male or female), with age varying from 19 to 48 years old were analyzed. All patients were diagnosted with mandibular retrognathism and submitted to bilateral sagital mandibular advancement. All tracings were performed in lateral cephalometric radiographs obtained one week before surgery. The intraclass correlation coefficient analysis (ICC), the t test adjusted for Tukey-Kramer test and Schuirmann test were applied. The results showed that the manual tracings and Nemotec® tracing had excellent reliabilities for all measures (ICC > 0.98). The Dolphin Imaging® showed low reliability in anterior facial height (value of ICC = 0.70), Co-A (value of ICC = 0.47) and Co-Gn (ICC value = 0.49). In A-Nperp, Pg-Nperp, Mandibular plan, SNA and SNB there were no differences between the 3 tracings (p > 0.05), for the anterior facial height measures differences were found between the Dolphin Imaging® and Nemotec® tracings, but no differences were observed as compared to the manual tracing (p > 0.05), in Co-A and Co-Gn measures t Dolphin Imaging® presented a significantly lower mean than the other methods (p > 0.05). The manual tracings were equivalent in 6 of 8 measures (A-Nperp, Pg-Nperp, md Plan, SNA, SNB and Co-A), there was no equivalence between the methods in the anterior facial height and Co-Gn measures (p < 0.01). The Dolphin Imaging® method was not equivalent in any of the 8 measures. It was concluded that in the manual tracing only the Co- Gn, Pg-Nperp and SNB measures confirmed the diagnosis of mandibular retrognathism, and the Nemotec® software showed better results than the Dolphin Imaging® software.

Biological Background on Bottlenose Dolphins (Tursiops spp.) in the 'Live-Capture' Trade and Specifically on the Indo-Pacific Bottlenose Dolphin, T. Aduncus

The most significant cetacean trade items until commercial whaling all but ceased in the 1990s (aside from scientific exchanges of tissues etc.) were meat and blubber from baleen whales for human consumption. Since then, live dolphins and 'small' whales for display (and to some extent for research, military use, and 'therapy') have become the most significant cetacean 'products' in international trade. Trade in live cetaceans is presently dominated by bottlenose dolphins (Tursiops spp.), beluga whales (Debhinapterns leucas) and to a lesser extent killer whales (Orcinus orca) (Fisher and Reeves 2005). In the past, most of the dolphins in trade were common bottlenose dolphins (Tursiops truncatus) originating in the United States, Mexico and the Black Sea, but since the 1980s the United States has essentially stopped its capture-for-export activities and in 2001Mexico implemented a moratorium on live-captures. The source countries for dolphins in trade are now geographically diverse, but Cuba and Japan are currently major source nations for common bottlenose dolphins. Russia is the only current source for belugas. Russia and Japan have become the main potential sources for killer whales since Iceland ceased exporting them in the 1980s or early 1990s.

Indo-Pacific Bottlenose Dolphin Assessment Workshop Report

A workshop on the assessment of Indo-Pacific bottlenose dolphins (Tursiops aduncus), with the Solomon Islands as a case study, took place from 21-23 August 2008 in Apia, Samoa. It was planned and organized under the auspices of the Cetacean Specialist Group and attended by 19 invited participants from eight countries. Financial support was provided by WWF (International), The Ocean Conservancy, Animal Welfare Institute, Humane Society of the United States, Whale and Dolphin Conservation Society, U.S. Marine Mammal Commission and U.S. National Oceanic and Atmospheric Administration. The workshop was hosted by the Secretariat of the Pacific Regional Environment Program (SPREP). Live-capture, holding in captivity and export of Indo-Pacific bottlenose dolphins from the Solomon Islands began in 2003. These activities stimulated global interest and generated concern about the potential conservation implications. The IUCN Global Plan of Action for the Conservation of Cetaceans had stated that as a general principle, small cetaceans should not be captured or removed from a wild population unless that specific population has been assessed and shown capable of sustaining the removals. A principal goal of the present workshop was to elaborate on the elements of an assessment that would meet this standard. Participants noted that an assessment involving delineation of stock boundaries, abundance, reproductive potential, mortality and trend cannot necessarily be achieved quickly or inexpensively.

Blind River Dolphin: First Side-Swimming Cetacean

The blind river dolphin (Platanista gangetica), first written about by Pliny the Elder in A.D. 72, was found (10 November 1968) to be the first known side-swimming cetacean. The rudimentary eye lacks the lens, but anatomical evidence suggests that the eye may serve as a light sensor. The underwater sound emissions of this species, although similar to those of the Amazon River dolphin (Inia geoffrensis), appear to be produced constantly.

Contamination by chlorinated pesticides, PCBs and PBDEs in Atlantic spotted dolphin (Stenella frontalis) in western South Atlantic

Chlorinated pesticides, PCBs and PBDEs were analysed in nine blubber samples of Atlantic spotted dolphins, Stenella frontalis, incidentally captured during fishing operations in southern and southeastern Brazil between 2005 and 2007. The majority of compounds analysed were detected, suggesting widespread contamination over the region. Although the samples came from a location far from main coastal industrial areas, the results revealed an influence from such sources. Therefore, levels of PCBs (774-23659 ng g(-1) lipid wt.) and PBDEs (23-1326 ng g(-1) lipid wt.) detected seem to be related to the movement of individuals throughout near-shore and offshore waters. The sample from a lactating female exhibited a lower level of contamination and a distinct pattern, indicating selective transfer favouring less lipophilic compounds.