Recent rapid increases in the right whale (Eubalaena australis) population off southern Brazil

Journal ArticleRight whales (Eubalaena australis) that gather on a wintering ground off southern Brazil have been aerial surveyed and photographically identified since 1987. As of 2003 the Brazilian Right Whale Catalogue has 315 different individual whales of which 31 were resighted in other years (23 females, 3 yearlings and 5 whales of unknown age/sex). No resightings occurred prior to 1994 and 71% (n=24) were recorded in 2003. The modal observed interval between calving events is 3 years, consistent with successful reproduction. From 1997 to 2003 the number of reproductive females in the Central Survey Area off Brazil increased at a rate of 29.8% per year (95% CL 15.7, 44.0), and at 14% per year (95% CL 7.1, 20.9) from 1987 to 2003. These rates are significantly different from zero (t=4.133, p<0.009 and t=4.06, p<0.004, respectively). The increase from 1997 to 2003 is higher than the rates observed for right whales in other wintering grounds in the South Atlantic. The right whales on the Brazilian wintering ground are not just transients. Ten percent of the whales have been resighted. If the number of whales continues to increase they will probably expand their distribution throughout their historical 2,400km range and come into increasing conflict with human activities

Animal-borne tags provide insights into the acoustic communication of southern right whales (Eubalaena australis) on the calving grounds

Funding: This study was supported by the Marine Mammal Commission under Grant No. MMC17-230. Additional support was provided by Cetacean Society International and VIVA Baleias, golfinhos ecia.This study investigated the repertoire, call-type variability and call rates of southern right whales on a calving ground off Brazil in the western South Atlantic. Acoustic tag data were collected from four lactating females and one juvenile. Pulsive, hybrid, and upcalls showed the greatest variability among call-types with up to 23% of non-standard forms detected. Quiet sounds (grunt, single, and double pulse) were detected for the first time in this species on the calving grounds. Although the sample size was limited, results suggest that social interaction increased call-type diversity and call rates, in line with other acoustic studies on right whales.Publisher PDFPeer reviewe

The recovery of North Atlantic right whales, Eubalaena glacialis, has been constrained by human-caused mortality

North Atlantic right whales (NARW), Eubalaena glacialis, were nearly exterminated by historical whaling. Their abundance slowly increased up until 2010, to a maximum of fewer than 500 whales, and since then they have been in decline. We assessed the extent to which the relatively slow increase demonstrated by NARW was intrinsic, and how much could be due to anthropogenic impacts. In order to do so, we first compared calf counts of three populations of Southern right whales (SRW), E. australis, with that of NARW, over the period 1992–2016. By this index, the annual rate of increase of NARW was approximately one-third of that of SRW. Next we constructed a population projection model for female NARW, using the highest annual survival estimates available from recent mark–resight analysis, and assuming a four-year calving interval. The model results indicated an intrinsic rate of increase of 4% per year, approximately twice that observed, and that adult female mortality is the main factor influencing this rate. Necropsy records demonstrate that anthropogenic mortality is the primary cause of known mortality of NARW. Anthropogenic mortality and morbidity has limited the recovery of NARW, and baseline conditions prior to their recent decline were already jeopardizing NARW recovery.The North Atlantic Right Whale Catalog is maintained with support from ongoing contracts from NOAA Fisheries. J.B. has been funded since at least 1993 by various Australian Government Environment Agencies, since 2015 the National Environment Marine Sciences Program, Marine Diversity Hub. K.F. thanks the Island Foundation for support during the collection of the South African aerial survey data between 2012 and 2015. Various institutions funded the South African aerial surveys over the data collection period, including Moby Dick Rum, Exclusive Trust, the Island Foundation, the National Research Foundation, members of the Offshore Petroleum Association of South Africa and the International Whaling Commission. The Brazilian Right Whale Catalog have been supported by several companies through funding to Projeto Baleia Franca, in particular PETROBRAS Brazilian Oil Company and Santos Brasil Company. V.R. thanks the many individuals and non-profit organizations who funded the 47 years of aerial surveys of the Argentine right whales, in particular Sarah Haney for her support in many of our lean years. V.R.’s research permits were issued annually by the Direccio´n de Fauna y Flora Silvestre and the Subsecretarı´a de Turismo y A ´ reas Protegidas of Chubut Province, Argentina.http://rsos.royalsocietypublishing.orgam2019Mammal Research InstituteZoology and Entomolog

Phocine distemper Virus: Current knowledge and future directions

Phocine distemper virus (PDV) was first recognized in 1988 following a massive epidemic in harbor and grey seals in north-western Europe. Since then, the epidemiology of infection in North Atlantic and Arctic pinnipeds has been investigated. In the western North Atlantic endemic infection in harp and grey seals predates the European epidemic, with relatively small, localized mortality events occurring primarily in harbor seals. By contrast, PDV seems not to have become established in European harbor seals following the 1988 epidemic and a second event of similar magnitude and extent occurred in 2002. PDV is a distinct species within the Morbillivirus genus with minor sequence variation between outbreaks over time. There is now mounting evidence of PDV-like viruses in the North Pacific/Western Arctic with serological and molecular evidence of infection in pinnipeds and sea otters. However, despite the absence of associated mortality in the region, there is concern that the virus may infect the large Pacific harbor seal and northern elephant seal populations or the endangered Hawaiian monk seals. Here, we review the current state of knowledge on PDV with particular focus on developments in diagnostics, pathogenesis, immune response, vaccine development, phylogenetics and modeling over the past 20 years

Predicción de los “hotspots” de reproducción de la ballena franca austral, Eubalaena australis (Cetartiodactyla: Mysticeti), en la costa sur de Brasil

To predict the potential breeding hotspots of southern right whales in southern Brazil, we used a Maxent model with a “presence-only” dataset. The dataset was obtained from a systematic aerial survey and public records of the Programa de Monitoramento de Cetáceos da Bacia de Santos and Sistema de Apoio ao Monitoramento de Mamíferos Marinhos. Because of spatial autocorrelation, 528 records out of 3028 were used in the modelling process. The explanatory variables used in the models were coastal distance, linearity, slope and substrate type. The models were created separately for unaccompanied adults (Ad) and mother-calf pairs (Fe). Both models showed good accuracy according to their area under the curve values (Ad=0.974; Fe=0.958). Coastal distance was the most relevant explanatory variable for the unaccompanied adult model (54%), whereas coastal linearity was more relevant for the mother-calf pair model (82%). The estimated area for mother-calf pairs was more restricted to coastal areas than that for unaccompanied adults, possibly owing to the high number of shelter areas for calves near the coast. This is the first study to predict the potential breeding hotspots of southern right whales in Brazil and its results will allow for a more directed management of these whales and provide further research opportunities.Para predecir los posibles “hotspots” de reproducción de las ballenas francas en el sur de Brasil, utilizamos un modelo Maxent con un conjunto de datos de “solo presencia”. El conjunto de datos se obtuvo de un estudio aéreo sistemático y registros públicos del “Programa de Monitoreo de Cetáceos da Bacia de Santos” y el “Sistema de Apoio ao Monitoramento de Mamíferos Marinhos”. Debido a la autocorrelación espacial, se usaron 528 registros de 3028 en el proceso de modelado. Las variables explicativas empleadas en los modelos fueron la distancia costera, la linealidad, la pendiente y el tipo de sustrato. Los modelos se crearon por separado para adultos no acompañados (Ad) y parejas madre-cría (Fe). Ambos modelos mostraron una buena precisión de acuerdo con sus valores de AUC (área bajo la curva: Ad=0,974; Fe=0,958). La distancia costera fue la variable explicativa más relevante para el modelo de adulto no acompañado (54%), mientras que la linealidad costera fue más relevante para el modelo de pareja madre-cría (82%). El área estimada para las parejas madre-cría estaba más restringida a las áreas costeras en comparación con el área prevista para los adultos no acompañados, posiblemente debido a la gran cantidad de áreas de refugio para las crías cerca de la costa. Este es el primer estudio que predice los posibles “hotspots” de reproducción de las ballenas francas en Brasil y sus resultados permitirán una gestión más dirigida de estas ballenas y brindarán más oportunidades de investigación

Povorot k intertekstual’nosti: razvenčanie ili ritorizacija vlijanija

Università degli Studi di Trieste - Scuola Superiore di Lingue Moderne per Interpreti e Traduttor

Long-term stability in the circumpolar foraging range of a Southern Ocean predator between the eras of whaling and rapid climate change

Assessing environmental changes in Southern Ocean ecosystems is difficult due to its remoteness and data sparsity. Monitoring marine predators that respond rapidly to environmental variation may enable us to track anthropogenic effects on ecosystems. Yet, many long-term datasets of marine predators are incomplete because they are spatially constrained and/or track ecosystems already modified by industrial fishing and whaling in the latter half of the 20th century. Here, we assess the contemporary offshore distribution of a wide-ranging marine predator, the southern right whale (SRW, Eubalaena australis), that forages on copepods and krill from ~30°S to the Antarctic ice edge (>60°S). We analyzed carbon and nitrogen isotope values of 1,002 skin samples from six genetically distinct SRW populations using a customized assignment approach that accounts for temporal and spatial variation in the Southern Ocean phytoplankton isoscape. Over the past three decades, SRWs increased their use of mid-latitude foraging grounds in the south Atlantic and southwest (SW) Indian oceans in the late austral summer and autumn and slightly increased their use of high-latitude (>60°S) foraging grounds in the SW Pacific, coincident with observed changes in prey distribution and abundance on a circumpolar scale. Comparing foraging assignments with whaling records since the 18th century showed remarkable stability in use of mid-latitude foraging areas. We attribute this consistency across four centuries to the physical stability of ocean fronts and resulting productivity in mid-latitude ecosystems of the Southern Ocean compared with polar regions that may be more influenced by recent climate change