(Tables 1,2) Polar bear (Ursus maritimus), beluga whale (Delphinapterus leucas) and ringed seal (Pusa hispida) liver microsomal protein content and EROD activity

The present study assessed and compared the oxidative and reductive biotransformation of brominated flame retardants, including established polybrominated diphenyl ethers (PBDEs) and emerging decabromodiphenyl ethane (DBDPE) using an in vitro system based on liver microsomes from various arctic marine-feeding mammals: polar bear (Ursus maritimus), beluga whale (Delphinapterus leucas), and ringed seal (Pusa hispida), and in laboratory rat as a mammalian model species. Greater depletion of fully brominated BDE209 (14-25% of 30pmol) and DBDPE (44-74% of 90pmol) occurred in individuals from all species relative to depletion of lower brominated PBDEs (BDEs 99,100, and 154; 0-3% of 30pmol). No evidence of simply debrominated metabolites was observed. Investigation of phenolic metabolites in rat and polar bear revealed formation of two phenolic, likely multiply debrominated, DBDPE metabolites in polar bear and one phenolic BDE154 metabolite in polar bear and rat microsomes. For BDE209 and DBDPE, observed metabolite concentrations were low to nondetectable, despite substantial parent depletion. These findings suggested possible underestimation of the ecosystem burden of total-BDE209, as well as its transformation products, and a need for research to identify and characterize the persistence and toxicity of major BDE209 metabolites. Similar cause for concern may exist regarding DBDPE, given similarities of physicochemical and environmental behavior to BDE209, current evidence of biotransformation, and increasing use of DBDPE as a replacement for BDE209.

Movement patterns and habitat use of the silver tip shark ("Carcharhinus albimarginatus") at the Revillagigedo Archipelago

[EN]The Revillegigedo Archipelago Biosphere Reserve is home to several shark species that spend at least part of their life history associated with oceanic islands associated with hotspots of pelagic biodiversity and in particular with apex predators. Silvertip sharks (Carcharhinus albimarginatus) are is commonly found in all the islands of the archipelago. However, very little is known about the spatial and temporal scales of their habitat use and associated ecological role. In this study, we employed passive acoustic telemetry to investigate the residency patterns and migration dynamics of 35 silvertip sharks tagged in three islands of the archipelago (San Benedicto, Socorro and Roca Partida) and monitored for a period of between 7 and 1165 (mean ± SD: 553.7± 354.2) days.

Stock assessment of whaler and hammerhead sharks (Carcharhinidae and Sphyrnidae) in Queensland

This stock assessment provides detailed results for the most common sharks encountered by Queensland commercial fishers. These sharks come from the whaler (Carcharhinidae) and hammerhead (Sphyrnidae) families and comprise sharpnose sharks (Rhizoprionodon taylori and R. oligolinx), the milk shark (R. acutus), the creek whaler (Carcharhinus fitzroyensis), the hardnose shark (C. macloti), the spot-tail shark (C. sorrah), the Australian blacktip shark (C. tilstoni), the common blacktip shark (C. limbatus), the spinner shark (C. brevipinna), bull and pigeye sharks (C. leucas and C. amboinensis), the winghead shark (Eusphyra blochii), the scalloped hammerhead (Sphyrna lewini) and the great hammerhead (S. mokarran). Reef sharks were excluded because fishery observer data indicated that they were largely spatially segregated from sharks caught in the inshore net fisheries. The three common species of reef sharks in Queensland, which are all whaler sharks, are the grey reef shark Carcharhinus amblyrhynchos, the blacktip reef shark C. melanopterus and the whitetip reef shark Triaenodon obesus.

A mitochondrial species identification assay for Australian blacktip sharks (Carcharhinus tilstoni, C. limbatus and C. amblyrhynchoides) using real-time PCR and high-resolution melt analysis

Tropical Australian shark fisheries target two morphologically indistinguishable blacktip sharks, the Australian blacktip (Carcharhinus tilstoni) and the common blacktip (C. limbatus). Their relative contributions to northern and eastern Australian coastal fisheries are unclear because of species identification difficulties. The two species differ in their number of precaudal vertebrae, which is difficult and time consuming to obtain in the field. But, the two species can be distinguished genetically with diagnostic mutations in their mitochondrial DNA ND4 gene. A third closely related sister species, the graceful shark C. amblyrhynchoides, can also be distinguished by species-specific mutations in this gene. DNA sequencing is an effective diagnostic tool, but is relatively expensive and time consuming. In contrast, real-time high-resolution melt (HRM) PCR assays are rapid and relatively inexpensive. These assays amplify regions of DNA with species-specific genetic mutations that result in PCR products with unique melt profiles. A real-time HRM PCR species-diagnostic assay (RT-HRM-PCR) has been developed based on the mtDNA ND4 gene for rapid typing of C. tilstoni, C. limbatus and C. amblyrhynchoides. The assay was developed using ND4 sequences from 66 C. tilstoni, 33. C. limbatus and five C. amblyrhynchoides collected from Indonesia and Australian states and territories; Western Australia, the Northern Territory, Queensland and New South Wales. The assay was shown to be 100% accurate on 160 unknown blacktip shark tissue samples by full mtDNA ND4 sequencing.

Reproductive aspects of the oceanic whitetip shark, Carcharhinus longimanus (Elasmobranchii: Carcharhinidae), in the equatorial and southwestern Atlantic Ocean

The present study sought to study the reproductive biology of the oceanic whitetip shark, Carcharhinus longimanus, in the equatorial and southwestern Atlantic Ocean. A total of 234 specimens were collected as bycatch during pelagic longline fisheries targeting tunas and swordfish, between December 2003 and December 2010. The fishing area was located between latitudes 10N and 35S and longitudes 3E and 40W. Of the 234 individuals sampled, 118 were females (with sizes ranging from 81 to 227 cm TL, total length) and 116 males (ranging from 80 to 242 cm TL). The reproductive stages of the females were classed as immature, mature, preovulatory and pregnant, while males were divided into immature, maturing and mature. The size at maturity for females was estimated at 170.0 cm TL, while that for males was between 170.0 and 190.0 cm TL. Ovarian fecundity ranged from 1 to 10 follicles and uterine fecundity from 1 to 10 embryos. The reproductive cycle of this species is most likely biennial, with parturition occurring once every two years.

Analysis of tissue responses to fin tagging in Australian carcharhinids

Tissue responses to the application of Rototags and Jumbo Rototags in the first dorsal fin of Carcharhinus melanopterus, C. obscurus and C. plumbeus were examined. The acute response included tissue tearing and haemorrhage and was present by 5 days post-tagging. The intermediate response had begun by 20 days post-tagging and continued beyond 207 days. This response involved decreased red blood cell activity as the inflammatory response commenced. The chronic response had begun by 301 days and was complete by 553 days with a layer of fibrous connective tissue walling off the tag. External damage to the fin was caused by continued abrasion by the tag. Repair scales were observed at 242 days using scanning electron microscopy and were confirmed histologically in 61- and 553-day samples. Repair scales were not seen in areas of continuous abrasion. No infection was observed in tissues surrounding the wound. Disruption of the fin surface was observed due to abrasion by the tag, but did not appear to cause a severe tissue reaction. The tissue responses observed were consistent with a normal, but relatively slow, healing in the vicinity of the tag wound. Use of Rototags or Jumbo Rototags appears to be an efficient way of marking elasmobranchs with minimal damage to the shark. (C) 1998 The Fisheries Society of the British Isles.

Observations on the diet and feeding habits of the epaulette shark, Hemiscyllium ocellatum (Bonnaterre), on Heron Island Reef, Great Barrier Reef, Australia

The diet and feeding habits of the epaulette shark, Hemiscyllium ocellatum, were investigated through stomach content analysis. Five groups of prey items were found. The index of relative importance showed worms and crabs,to be of greatest value at 51.3% and 40.1% respectively. The three minor prey groups were shrimps (7.7%), small fishes (0.7%) and amphipods (0.3%). Epaulette sharks tend to be crepuscular, although feeding bouts may occur at any time. They appear to be opportunistic predators, using olfaction and electroreception in prey capture. This species appears to be an important benthic predator in the reef flat environment on Heron Island Reef.

Ion and urea regulation in elasmobranch fish

In recent years our understanding of the control of ion and urea metabolism in elasmobranch fish has increased with many more species being investigated. This has demonstrated that many species regarded as stenohaline marine are at least, partially euryhaline and may survive in environments less concentrated than full seawater. This presentation will review these recent findings and then compare the osmoregulatory strategies of a partially euryhaline species, Scyliorhinus canicula, with a fully euryhaline migratory species Carcharinus leucas. This will include new data for both species and will generate new models for the control of ion and urea metabolism in elasmobranchs on which to base future research.

Faunes ichthyologiques du Néogène Supérieur d’Angola, leur âge, remarques sur le Pliocène marin en Afrique Australe

This note is concerned with fish remains from Upper Neogene beds at Farol das Lagostas (and nearby quarry of SECIL) and Baía Farta, mainly recovered by the author in 1960, 1961, 1963 and 1967. For further data see ANTUNES, 1964, pp. 213-215. All the forms identified until now (many of them for the first time) are show in «tableau I». Smaller ones are poorly represented. I. benedeni is provisorily accepted as a distinct species, though it may correspond to a dental morphotype that does exist equally in the extant I. oxyrhinchus (see text): therefore I. benedeni from Farol das Lagostas may after all represent only some dental variations that really belong in the form described as I. cf. oxyrhinchus. The presence of Aprionodon and Hypoprion could not be ascertained: Procarcharodon megalodon, Carcharodon carcharias, Isurus benedeni. Galeocerdo cuvieri, and Carcharhinus sp. I and sp. II are specially discussed. The whole fauna does not correspond either to a very shallow and coastal environment, or to deep waters far away from the coast. It clearly points out to warm waters: an acceptable model would be the fauna from the tropical Atlantic between Northern Angola and Senegal-Cape Verde. The age of this fauna was long regarded as Burdigalian. The data formerly presented (ANTUNES, 1963) that allowed us to ascribe a pliocene age to the uppermost Neogene beds of Farol das Lagostas (Neogene III, ANTUNES, 1964) are reviewed and developed in this paper. This view is corroborated by planctonic foraminifera and stratigraphical data which provide further evidence to prove the presence of miocene beds much younger than Burdigalian, and that some deposits previously correlated to this stage have instead a Plio-Pleistocene age. Fish fauna from Farol das Lagostas is very characteristic, with giant P. megalodon in association with C. carcharias (which predominates, and whose stratigraphical distribution is particularly discussed), and with other very advanced forms like the extant tiger shark, G. cuvieri, enormous I. Benedeni, Hemipristis, and Carcharhinus (whose size largely exceeds the maximum observed with miocene material). With the exception of P. megalodon (extinct) all the other forms show very close affinities, or even identity with modern species. Comparisons with very similar faunas from some South African localities that may also have a Pliocene age are also presented.

Faunes ichthyologiques du Néogène Supérieur d’Angola, leur âge, remarques sur le Pliocène marin en Afrique Australe

This note is concerned with fish remains from upper Neogene beds at Farol das Lagostas (and nearby quarry of SECIL) and Baía Farta, mainly recovered by the author in 1960, 1961, 1963 and 1967. For further data see ANTUNES, 1964, pp. 213-215. All the forms identified until now (many of them for the first time) are show in «tableau I». Smaller ones are poorly represented. I. benedeni is provisorily accepted as a distinct species, though it may correspond to a dental morphotype that does exist equally in the extant I. oxyrhinchus (see text): therefore I. benedeni from Farol das Lagostas may after all represent only some dental variations that really belong in the form described as I. cf. oxyrhinchus. The presence of Aprionodon and Hypoprion could not be ascertained: Procarcharodon megalodon, Carcharodon carcharias, Isurus benedeni. Galeocerdo cuvieri, and Carcharhinus sp. I and sp. II are specially discussed. The whole fauna does not correspond either to a very shallow and coastal environment, or to deep waters far away from the coast. It clearly points out to warm waters: an acceptable model would be the fauna from the tropical Atlantic between Northern Angola and Senegal-Cape Verde. The age of this fauna was long regarded as Burdigalian. The data formerly presented (ANTUNES, 1963) that allowed us to ascribe a pliocene age to the uppermost Neogene beds of Farol das Lagostas (Neogene III, ANTUNES, 1964) are reviewed and developed in this paper. This view is corroborated by planctonic foraminifera and stratigraphical data which provide further evidence to proove the presence of miocene beds much younger than Burdigalian, and that some deposits previously correlated to this stage have instead a Plio-Pleistocene age. Fish fauna from Farol das Lagostas is very characteristic, with giant P. megalodon in association with C. carcharias (which predominates, and whose stratigraphical distribution is particularly discussed), and with other very advanced forms like the extant tiger shark, G. cuvieri, enormous I. Benedeni, Hemipristis, and Carcharhinus (whose size largely exceeds the maximum observed with miocene material). With the exception of P. megalodon (extinct) all the other forms show very close affinities, or even identity with modern species. Comparisons with very similar faunas from some South African localities that may also have a Pliocene age are also presented.

Dasyrhynchus pacificus Robinson, 1965 (Trypanorhyncha: Dasyrhynchidae) description of the adult form

One out of four specimens of sharks, Carcharhinus brachyurus (Günther, 1860), captured off the southern Brazilian Coast, harboured cestodes identified as Dasyrhynchus pacificus Robinson, 1965, of which the adult form is now described and referred as ocurring in Brazil.

Taxonomic reports of Otobothrioidea (Eucestoda, Trypanorhyncha) from elasmobranch fishes of the southern coast off Brazil

Specimens of elasmobranch fishes, captured in the states of Paraná and Santa Catarina, of the southern coast off Brazil, represented by three families, four genera, and four species, were parasitized with otobothrioid trypanorhynch cestodes: Heptranchias perlo (Bonnaterre, 1788), Squalus sp. and Carcharhinus signatus (Poey, 1868) were parasitized with Progrillotia dollfusi Carvajal & Rego,1987; Prionace glauca (Linnaeus, 1758) with Molicola horridus (Goodsir, 1841) Dollfus, 1942. Details of internal morphology and/or scolex and/or proglottids surface ultrastructure, that expanded the description of M. horridus, through observations with lightfield, and/or scanning eletronic microscopy, are provided. The known geographical distribution for the species M. horridus is enlarged. P. dollfusi is reported for the first time in elasmobranchs.

Influência do tipo e da quantidade de resíduos vegetais na emergência de plantas daninhas

Com o objetivo de avaliar os efeitos da semeadura no outono/inverno de diferentes espécies: sorgo de cobertura (Sorghum bicolor x Sorghum sudanense 'híbrido Cober Exp'), milheto forrageiro (Pennisetum americanum 'var. BN2'), capim-pé-de-galinha (Eleusine coracana) e braquiária (Brachiaria brizantha) para formação de palha (nas quantidades de 3,0 e 5,5 t ha¹), na emergência de plantas daninhas, foi conduzido experimento no ano agrícola 2003/04, na fazenda Três Marcos, em Uberlândia, MG. Foi mantida uma testemunha como tratamento adicional, sem cobertura com restos vegetais. A composição específica e as densidades populacionais das comunidades infestantes foram influenciadas pelos sistemas de produção de cobertura morta. A emergência das plantas daninhas foi menor nas coberturas de sorgo e braquiária e nos maiores níveis de palha. O número de plântulas emergidas de Bidens pilosa, Amaranthus spp., Commelina benghalensis, Leucas martinicensis e gramíneas foi inibido pelas coberturas, enquanto para Chamaesyce spp. os resíduos contribuíram para incremento na sua emergência.

Utilização de chlorimuron-ethyl e imazethapyr na cultura da soja Roundup Ready®

Objetivou-se com este trabalho avaliar a eficácia e a seletividade da associação dos herbicidas chlorimuron-ethyl e imazethapyr ao glyphosate no controle de plantas daninhas na cultura da soja Roundup Ready® (RR®). O experimento foi realizado no Centro Tecnológico da COMIGO, localizado no município de Rio Verde-GO, na safra 2005/2006. A semeadura do cultivar Monsoy 7878 foi realizada mecanicamente, sendo a semeadora regulada para liberar 18 sementes por metro. O espaçamento utilizado entre linhas foi de 0,50 m. O delineamento experimental foi o de blocos ao acaso, com quatro repetições. A aplicação isolada de glyphosate nas doses de 480, 960 e 1.440 g ha-1 não causou intoxicação e não reduziu a altura e o acúmulo de massa seca das plantas de soja RR®. A adição dos herbicidas imazethapyr e chlorimuron-ethyl ao glyphosate ocasionou intoxicação às plantas de soja RR®, todavia em níveis aceitáveis, sendo os sintomas provocados pela ação do imazethapyr mais intensos em comparação aos do chlorimuron-ethyl. A associação do herbicida imazethapyr ao glyphosate reduziu a altura e o acúmulo de fitomassa das plantas de soja RR®. A aplicação isolada de glyphosate nas doses de 480, 960 e 1.440 g ha-1 não apresentou controle satisfatório das plantas daninhas Euphorbia heterophylla, Commelina benghalensis, Chamaesyce hirta, Leucas martinicensis e Ipomoea grandifolia. Apesar de incrementar o controle da maioria das plantas daninhas, a adição dos herbicidas chlorimuron-ethyl e imazethapyr ao glyphosate não promoveu aumento de produtividade de grãos na cultura da soja RR®.