32 research outputs found
Ocean warming threatens southern right whale population recovery
Funding: This work was supported by CAPES doctoral scholarship (M.A.), CAPES-PRINT grant 88887.370641/2019-00 (M.A.), CNPQ research grant 305573/2013-6 (P.C.S.-L.), and CNPQ research grant 407190/2012-0 (F.G.D.-J.). Funding for aerial surveys since 1971 was provided by numerous donors through Ocean Alliance and Instituto de Conservación de Ballenas such as Wildlife Conservation Society, National Geographic Society, World Wildlife Fund, Alfredo Fortabat Foundation, Turner Foundation, Canadian Whale Institute, I. Kerr, A. L. de Fortabat, S. Haney, A. and J. Moss, A. Morse, P. Singh, P. Logan, N. Griffis, and C. Walcott.Whales contribute to marine ecosystem functioning, and they may play a role in mitigating climate change and supporting the Antarctic krill (Euphausia superba) population, a keystone prey species that sustains the entire Southern Ocean (SO) ecosystem. By analyzing a five-decade (1971–2017) data series of individual southern right whales (SRWs; Eubalaena australis) photo-identified at Península Valdés, Argentina, we found a marked increase in whale mortality rates following El Niño events. By modeling how the population responds to changes in the frequency and intensity of El Niño events, we found that such events are likely to impede SRW population recovery and could even cause population decline. Such outcomes have the potential to disrupt food-web interactions in the SO, weakening that ecosystem’s contribution to the mitigation of climate change at a global scale.Publisher PDFPeer reviewe
Epidemiology of lobomycosis-like disease in bottlenose dolphins Tursiops spp. from South America and southern Africa
We report on the epidemiology of lobomycosis-like disease (LLD), a cutaneous disorder
evoking lobomycosis, in 658 common bottlenose dolphins Tursiops truncatus from South America
and 94 Indo-Pacific bottlenose dolphins T. aduncus from southern Africa. Photographs and stranding
records of 387 inshore residents, 60 inshore non-residents and 305 specimens of undetermined origin
(inshore and offshore) were examined for the presence of LLD lesions from 2004 to 2015. Seventeen
residents, 3 non-residents and 1 inshore dolphin of unknown residence status were positive.
LLD lesions appeared as single or multiple, light grey to whitish nodules and plaques that may ulcerate
and increase in size over time. Among resident dolphins, prevalence varied significantly
among 4 communities, being low in Posorja (2.35%, n = 85), Ecuador, and high in Salinas, Ecuador
(16.7%, n = 18), and Laguna, Brazil (14.3%, n = 42). LLD prevalence increased in 36 T. truncatus
from Laguna from 5.6% in 2007−2009 to 13.9% in 2013−2014, albeit not significantly. The disease
has persisted for years in dolphins from Mayotte, Laguna, Salinas, the Sanquianga National Park
and Bahía Málaga (Colombia) but vanished from the Tramandaí Estuary and the Mampituba River
(Brazil). The geographical range of LLD has expanded in Brazil, South Africa and Ecuador, in areas
that have been regularly surveyed for 10 to 35 yr. Two of the 21 LLD-affected dolphins were found
dead with extensive lesions in southern Brazil, and 2 others disappeared, and presumably died, in
Ecuador. These observations stress the need for targeted epidemiological, histological and
molecular studies of LLD in dolphins, especially in the Southern Hemisphere.The Conselho Nacional de Desenvolvimento Científico e
Tecnológico (CNPq) to E.R.S. (PQ 307846/2014-8) and P.H.O.
(Process 572180/2008-0), and L.F. was sponsored by Petrobras through Petrobras Socio
Ambiental.http://www.int-res.com/journals/dao/dao-home/2020-11-30am201
Seasonal variations in spatial usage by the estuarine dolphin, Sotalia guianensis (van Bénéden, 1864) (Cetacea; Delphinidae) at its southern limit of distribution
Microneedles: A New Frontier in Nanomedicine Delivery
This review aims to concisely chart the development of two individual research fields, namely nanomedicines, with specific emphasis on nanoparticles (NP) and microparticles (MP), and microneedle (MN) technologies, which have, in the recent past, been exploited in combinatorial approaches for the efficient delivery of a variety of medicinal agents across the skin. This is an emerging and exciting area of pharmaceutical sciences research within the remit of transdermal drug delivery and as such will undoubtedly continue to grow with the emergence of new formulation and fabrication methodologies for particles and MN. Firstly, the fundamental aspects of skin architecture and structure are outlined, with particular reference to their influence on NP and MP penetration. Following on from this, a variety of different particles are described, as are the diverse range of MN modalities currently under development. The review concludes by highlighting some of the novel delivery systems which have been described in the literature exploiting these two approaches and directs the reader towards emerging uses for nanomedicines in combination with MN
Non-metric characters in two species of Sotalia (Gray, 1866) (Cetacea, Delphinidae)
Analyses of non-metric characters of the skull and cervical vertebrae were performed among samples of dolphins of the genus Sotalia from the north, northeast and south Brazilian coast (S. guianensis) and also samples from the Amazon River Basin (S. fluviatilis) as part of an osteological descriptive study. The results demonstrated that there was a higher percentage of occurrence of fenestrae in the occipital region (66%) and cervical ribs in the cervical vertebrae (87%) in the riverine species. The vomer in wide shape was more frequent in the riverine species (57%), followed by the intermediate (32%) and narrow shape (11%), that was found to be more frequent in the marine species (66 to 76%). In relation to the lacerate anterior foramen, it was observed that an open/elongated shape is more common in the riverine species (88%). Most samples in the marine species present this foramen divided by a spike shaped projection (72 to 98%). The ventrally visible location of the hypoglossal foramen was more often observed externally displaced in S. guianensis (88 to 98%), while in S. fluviatilis, most samples (87%) presented this foramen internally displaced to the jugular notch, and not visible in ventral view. The fluvial species seems to present neoteny (or maintenance of juvenile characters in adults) in relation to the position of the pterygoids and in development of lacerate anterior foramen
Cetacean records along a coastal-offshore gradient in the Vitória-Trindade Chain, western South Atlantic Ocean
Oceanic waters are difficult to assess, and there are many gaps in knowledge regarding cetacean occurrence. To fill some of these gaps, this article provides important cetacean records obtained in the winter of 2010 during a dedicated expedition to collect visual and acoustic information in the Vitória-Trindade seamounts. We observed 19 groups of cetaceans along a 1300-km search trajectory, with six species being identified: the humpback whale (Megaptera novaeangliae, N = 9 groups), the fin whale (Balaenoptera physalus, N = 1), the Antarctic minke whale (Balaenoptera bonaerensis, N = 1), the rough-toothed dolphin (Steno bredanensis, N = 1), the bottlenose dolphin (Tursiops truncatus, N = 2), and the killer whale (Orcinus orca, N = 1). Most humpback whale groups (N = 7; 78%) were observed in the Vitória-Trindade seamounts, especially the mounts close to the Abrolhos Bank. Only one lone humpback whale was observed near Trindade Island after a search effort encompassing more than 520 km. From a total of 28 acoustic stations, humpback whale songs were only detected near the seamounts close to the Abrolhos Bank, where most groups of this species were visually detected (including a competitive group and groups with calves). The presence of humpback whales at the Trindade Island and surroundings is most likely occasional, with few sightings and low density. Finally, we observed a significant number of humpback whales along the seamounts close to the Abrolhos Bank, which may function as a breeding habitat for this species. We also added important records regarding the occurrence of cetaceans in these mounts and in the Western South Atlantic, including the endangered fin whale
Cetacean records along a coastal-offshore gradient in the Vitória-Trindade Chain, western South Atlantic Ocean
Oceanic waters are difficult to assess, and there are many gaps in knowledge regarding cetacean occurrence. To fill some of these gaps, this article provides important cetacean records obtained in the winter of 2010 during a dedicated expedition to collect visual and acoustic information in the Vitória-Trindade seamounts. We observed 19 groups of cetaceans along a 1300-km search trajectory, with six species being identified: the humpback whale (Megaptera novaeangliae, N = 9 groups), the fin whale (Balaenoptera physalus, N = 1), the Antarctic minke whale (Balaenoptera bonaerensis, N = 1), the rough-toothed dolphin (Steno bredanensis, N = 1), the bottlenose dolphin (Tursiops truncatus, N = 2), and the killer whale (Orcinus orca, N = 1). Most humpback whale groups (N = 7; 78%) were observed in the Vitória-Trindade seamounts, especially the mounts close to the Abrolhos Bank. Only one lone humpback whale was observed near Trindade Island after a search effort encompassing more than 520 km. From a total of 28 acoustic stations, humpback whale songs were only detected near the seamounts close to the Abrolhos Bank, where most groups of this species were visually detected (including a competitive group and groups with calves). The presence of humpback whales at the Trindade Island and surroundings is most likely occasional, with few sightings and low density. Finally, we observed a significant number of humpback whales along the seamounts close to the Abrolhos Bank, which may function as a breeding habitat for this species. We also added important records regarding the occurrence of cetaceans in these mounts and in the Western South Atlantic, including the endangered fin whale