Biology and ecology of bottlenose dolphins (Tursiops truncatus) stranded and sighted at 25°S in the south-western Atlantic Ocean during 1989–2016

Historical strandings and sightings (1989-2016) of Tursiops truncatus at 25S in the south-western Atlantic Ocean (Paraná, Brazil) were assessed to (1) investigate temporal fluctuations; and (2) quantify biological, ecological and health parameters of regional populations. In total, 57 T. truncatus carcasses in mostly advanced stages of decomposition (~80% of all specimens) were recorded. Standardized temporal strandings (per observational effort) varied considerably and with no clear annual relationship beyond a peak in 2007, but there were consistently more strandings in winter/spring (74%) than summer/autumn (26%). While there was uncertainty over age estimation (i.e. not available for the population), individuals classified as juveniles/subadults were more frequent (80%) than calves (14%) and adults (6%). Of 28 carcasses assessed, 27 showed a positive linear relationship between TL and condyle-basal length, while one specimen had a clear southern skull morphotype. Suggestive lesions of Crassicauda sp. were recorded in 77% of assessed skulls and four types of tooth pathologies were observed. Nine individuals were more closely investigated for gross and histopathological alterations and had clear evidence of fishery interactions and various health issues associated with disease and oedema accompanied by alveolar fibrosis. While the regional frequency of T. truncatus strandings was lower than other more vulnerable cetaceans, the absolute numbers (e.g. 15 individuals in 2016) and some uncertainty concerning regional taxonomy are noteworthy, and justify ongoing spatio-temporal monitoring. Further, given the evidence of disease in some specimens, future work should not only encompass rigorous taxonomic assessments, but also health to comprehensively evaluate regional stocks. Small cetacean species are sentinels and their condition could inform ongoing environmental assessments

Nonlinear Variability in the Geomagnetic Secular Variation of the Last 150 Years

A nonlinear forecasting analysis has been applied to the secular variation of the three-component annual means of 14 observatories, unevenly distributed over the Earth's surface (12 in the northern and 2 in the southern hemisphere) and spanning the last 150 years. All results were in agreement, either in terms of possible evidence of chaos (as opposed to the hypothesis of white or colored noise), or in terms of the Kolmogorov entropy, confirming previous results obtained with only three European observatories, i.e. it is practically impossible to predict the secular variation of the geomagnetic field more than six years into the future

Macroscopic and microscopic findings associated with inflammatory processes.

<p>A: <i>Globicephala melas</i>: Pulmonary edema. B: <i>Sotalia guianensis</i>: Chronic bronchointerstitial pneumonia associated with morbillivirus infection and <i>Halocercus brasiliensis</i> (not in the figure) (HE, 4x) and positive immunostaining for CDV (insert, 40x). C: Granulomatous lymphadenitis with giant cells (arrow) (HE, 20x). D: Membranous glomerulonephritis (arrows) (HE, 20x).</p

Paranaguá estuarine complex and adjacent coastal area from Pontal do Sul to Matinhos, Paraná, Brazil.

<p>Areas with stranded animals are designated by black dots, while harbor zones are within red lines.</p

Diagram of small cetacean mortalities, with the numbers of carcasses recovered, diagnosed, and the collected samples and lesions according to different causes of death.

<p>Diagram of small cetacean mortalities, with the numbers of carcasses recovered, diagnosed, and the collected samples and lesions according to different causes of death.</p

Macroscopic and microscopic findings of <i>Sotalia guianensis</i> that died of natural causes.

<p>A: <i>Halocercus brasiliensis</i> in bronchi and bronchiole lumens, with pneumonia the cause of death (COD). B: Chronic bronchointerstitial pneumonia caused by adults <i>H</i>. <i>brasiliensis</i> (arrows) (HE, 10x). C: Lung angiomatosis (Masson’s trichrome, 20x). D: Emaciation COD, muscular atrophy of dorsal cephalic musculature, multifocal ulcerated areas on skin (arrows).</p

Macroscopic findings supporting evidence of interactions between <i>Sotalia guianensis</i> and anthropogenic activities.

<p>A and B: Impression from gillnet entanglement at the head, behind the eyes, fin and encircling the thoracic and abdominal regions. C: Fluke amputation and haemorrhage. D: A hook deeply embedded in the mouth, and line encircling the body to the abdomen producing multifocal hematoma, haemorrhage and trauma with evisceration and intestine perforation (insert).</p

Chelonid alphaherpesvirus 5 DNA in Fibropapillomatosis-affected Chelonia mydas

Fibropapillomatosis is a panzootic and chronic disease among Chelonia mydas-usually associated with anthropogenic impacts. This study contributes towards understanding fibropapillomatosis implications for C. mydas populations as a reflector of environmental quality, via prevalence and histological, molecular and blood analyses at a World Heritage site in southern Brazil. Sixty-three juvenile C. mydas (31.3-54.5\ua0cm curved carapace length-CCL) were sampled during two years. Eighteen specimens (~ 29%) had tumours (which were biopsied), while 45 had none. Degenerative changes in the epidermis and Chelonid alphaherpesvirus 5 DNA detection with three variants support a herpesvirus infection. Phylogenetic analysis indicated that variants A and B were similar to a herpesvirus lineage from the Atlantic group, but variant C was similar to a herpesvirus from the eastern Pacific lineage and represents the first published case for marine turtles off Brazil. Significantly lower levels of seven blood parameters, but greater numbers of eosinophils, were observed in tumour-afflicted animals. These observations were attributed to metabolism efficiencies and/or differences in diet associated with temporal-recruitment bias and disease development, and greater non-specific immune stimulation. While most animals had adequate body condition independent of disease, longer-term studies are required to elucidate any protracted population effects