Using an unbaited stationary video system to investigate the behaviour and interactions of bull sharks Carcharhinus leucas under an aquaculture farm     

N Loiseau  JJ Kiszka  T Bouveroux  MR Heithaus  M Soria  P Chabanet 《African Journal of Marine Science》2016,38(1):73-79

Bull sharks Carcharhinus leucas are common along the coast of Reunion Island (South-West Indian Ocean) and were suspected to aggregate in the vicinity of an aquaculture farm in Saint-Paul Bay on the west coast. In order to understand the behaviour and interaction of bull sharks near aquaculture cages at Saint-Paul Bay, we deployed an experimental unbaited stationary video camera. From 175 hours of recording during daylight hours from March to April 2012, eight individual female bull sharks (seven adults and one immature) were identified based on their natural markings. These sharks were resighted between 3 and 45 times. Residency analysis revealed site attachment under the aquaculture cages for at least three individuals over the course of the study. Recorded behaviours included intraspecific social interactions such as synchronised swimming. Social interactions and relatively strong paired associations for two pairs of females suggest some level of sociality among bull sharks around Reunion Island. Overall, our results demonstrate the utility of unbaited video systems to monitor the behaviour of adult coastal sharks.  相似文献   

The impact of oestrogenic and androgenic contamination on marine organisms in the United Kingdom--summary of the EDMAR programme. Endocrine Disruption in the Marine Environment     

Matthiessen P  Allen Y  Bamber S  Craft J  Hurst M  Hutchinson T  Feist S  Katsiadaki I  Kirby M  Robinson C  Scott S  Thain J  Thomas K 《Marine environmental research》2002,54(3-5):645-649

This paper summarises results of the EDMAR programme which is investigating oestrogenic and androgenic endocrine disruption in UK coastal waters. Most of the data concern fish. Four species (flounder, viviparous blenny and two sand gobies) are experiencing feminisation in industrialised estuaries. In males this includes vitellogenin (VTG) synthesis, ovotestis induction and/or feminised sexual characteristics. Although reproductive success may be impaired in some cases, implications for fish populations are still unclear. Suspected causative contaminants include natural oestrogenic substances and synthetic oestrogen mimics. The majority of the oestrogenic activity is adsorbed to sediments, and routes of exposure may include benthic food chain transfer. Some natural androgenic substances are also being discharged to estuaries, but their activity appears low.  相似文献   

Observations of the 3.3-μm UIR band in the Red Rectangle: relation to unidentified optical emission     

T. H. Kerr  M. E. Hurst  J. R. Miles  P. J. Sarre 《Monthly notices of the Royal Astronomical Society》1999,303(3):446-454

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Reply by the authors     

J.M. Hurst  N.J. Hancock  W.S. McKerrow 《Proceedings of the Geologists' Association. Geologists' Association》1979,90(4):231-232

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Feeding habits of age-0 striped bass,<Emphasis Type="Italic">Morone saxatilis</Emphasis>, in the mid-Hudson River estuary: Temporal,spatial, and ontogenetic variation     

Rebecca?C.?JordanEmail author  David?V.?Howe  Thomas?P.?Hurst  Francis?Juanes 《Estuaries and Coasts》2003,26(6):1486-1493

We quantified temporal and spatial variability in diets of 950 juvenile (age-0) striped bass in the Hudson River estuary. We used canonical correspondence analysis to assess the roles of temporal and spatial habitat variability in juvenile diet variation. We found that juvenile striped bass diets in the Hudson River were only modestly comparable to diets in other east coast estuaries. Among-year differences (51.4%) and spatial differences (41.9%) were substantially associated with juvenile striped bass diet. We found ontogeny (2.8%) and within-season variation (9.5%) to only weakly associate with diet variation. Our results indicate that an understanding of the temporal and spatial variation within the Hudson River estuary is vital in understanding variation in feeding by resident juvenile fish.  相似文献   

Acoustic noise and temperature monitoring of the Crater Lake of Mount Ruapehu Volcano     

A.W. Hurst  Jean Vandemeulebrouck 《Journal of Volcanology and Geothermal Research》1996,71(1):45-51

Acoustic signals in Ruapehu Crater Lake, which are now being telemetered via a satellite transmission system, show promise as a possible precursor of increased volcanic activity from Ruapehu. The start of a recent period of rapid heating of Crater Lake was preceded by low-frequency (2 Hz) acoustic signals. These accompanied similar frequency seismic signals, but seemed to be produced independently. Audio-frequency (350–3000 Hz) acoustic noise also showed a very clear peak shortly before the lake temperature started to rise.  相似文献   

Author's reply     

R.W. Hurst 《Geochimica et cosmochimica acta》1978,42(10):1585-1586

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Mass‐wasting of ancient aeolian dunes and sand fluidization during a period of global warming and inferred brief high precipitation: the Hopeman Sandstone (late Permian), Scotland     

Andrew Hurst  Kenneth W. Glennie 《地学学报》2008,20(4):274-279

Large‐scale deformation structures in late Permian aeolian dune sands are associated with sand fluidization and injection. Exceptional precipitation and flooding of the desert margin are believed to have caused mass‐wasting by gravitational collapse and sliding of water‐saturated dunes, which loaded down‐dip strata, thus generating overpressure and triggering sand injection. This short‐lived but heavy precipitation seems to have been associated with a climatic change from arid Rotliegend dune deposition to widespread Zechstein marine conditions within the greater North Sea area, probably just before or coinciding with deposition of the rapidly expanding marine Kupferschiefer.  相似文献   

Vertical and lateral organization of a carbonate deep-water slope marginal to a submarine fan system, Miocene, southern Turkey     

Bryan T. Cronin  Kemal GÜrbÜz  rew Hurst  & Nick Satur 《Sedimentology》2000,47(4):801-824

Organization is recognized in the forereef–deep water slope–submarine fan system of the Burdigalian-Langhian Kaplankaya Formation. A basinwards transition from a prograding shelfal reef complex, through forereef talus, deep-water slope and laterally encroaching bypass deep-water clastic system is described, although the deep-water slope makes up the bulk of the succession. Considerable thickness variations occur between the reef and deep-water clastic complexes; these are controlled by sea-floor topography, carbonate foreslope gradient and degree of mass wasting off the platform and foreslope. The vertical and lateral heterogeneity of the Kaplankaya deep-water slope system is described from a number of localities along a 40-km-long and up to 3-km-wide exposed section of the northern margin of the Miocene Adana Basin, a foreland basin setting resulting from thrust sheet loading from the north during the Tauride Orogeny. Detailed field mapping is supplemented with vertical sedimentary logs, photomosaics, palaeontological and petrological data to investigate stratal variation, diagnostic architectural elements, controls on slope progradation, differential timing of basinward encroachment of the reefal complex and lateral onlap of the deep-water clastic system onto the slope. Three-dimensional models are presented showing the vertical and lateral facies associations in different parts of the deep-water slope system, and provide a basis for architectural prediction of geometry and relative position in such environments.  相似文献   

IRAS 12311−3509: a carbon star with SiC₂ emission     

T. Lloyd Evans  M. E. Hurst  P. J. Sarre 《Monthly notices of the Royal Astronomical Society》2000,319(1):111-120

The optical spectrum of the carbon star IRAS 12311−3509 is dominated by the Merrill–Sanford emission bands of SiC₂, by absorption and emission in the Swan system of C₂, and by resonance emission lines of neutral metals. The infrared energy distribution is flat from 1 to 60 μm. These observations are interpreted as arising from a star with a cool dusty disc which is edge-on to the observer and obscures direct starlight. The infrared continuum is caused predominantly by absorption of stellar light by dust in the disc and re-emission at longer wavelengths. The optical stellar spectrum is seen by reflection off dusty material which lies out of the plane of the disc, and the molecular and atomic emission arises in the same geometry through resonance fluorescence. The object has similarities to the J-silicate stars, but may have a carbon-rich rather than oxygen-rich disc. A full spectroscopic assignment and discussion of the SiC₂ bands and their intensities are given. Modelling of the rotational contours of the     band yields a rotational temperature of 250 K, indicating very cool gas.  相似文献