scholarly journals Temporal and spatial variation in adult and juvenile mobile fauna associated with natural and artificial coastal habitats

2021 ◽  
Vol 168 (2) ◽  
Author(s):  
Alice E. Hall ◽  
Roger J. H. Herbert ◽  
Richard Stafford
Keyword(s):  
Dicentrarchus Labrax ◽  
Early Summer ◽  
Coastal Habitats ◽  
Artificial Structures ◽  
Artificial Habitats ◽  
Mobile Species ◽  
Spatial And Seasonal Variation ◽  
Black Bream ◽  
Temporal And Spatial ◽  
Natural Reefs

AbstractCoastal habitats are important for commercially exploited and protected species of fish and larger mobile invertebrates. The addition of artificial structures within the marine environment has the potential to alter the connectivity between habitats and to affect metapopulations of a region. Baited remote underwater videos (BRUV) were used to investigate the spatial and seasonal variation in abundance of adult and juvenile mobile species associated with subtidal natural and artificial habitats within Poole Bay on the south coast of England in 2019. Metrics included the relative maximum abundance (MaxN), number of species seen (S), assemblage structure and size range of fish. Higher values of MaxN and S were recorded on artificial structures in the spring and early summer; however, this pattern was reversed by mid-summer and early autumn when more fish were recorded on the natural reefs. Yet overall differences in MaxN and S between habitats were not significant. Differences in assemblage composition between habitats varied monthly, but this was mostly driven by particular sites. Although most fish observed were juveniles, there were some seasonal differences in the size of fish using natural and artificial sites, especially bib (Trisopterus luscus), black bream (Spondyliosoma cantharus), bass (Dicentrarchus labrax) and pollack (Pollachius pollachius). The artificial habitats in this region appeared to be important in certain months, so temporal studies of this type need to be incorporated within surveys, particularly those in proximity to protected areas.

Escaped introduced sea bass (Dicentrarchus labrax) infected by Sphaerospora testicularis (Myxozoa) reach maturity in coastal habitats off Canary Islands

2011 ◽  
Vol 33 (1) ◽  
pp. 26-31 ◽  
Author(s):  
Kilian Toledo-Guedes ◽  
Pablo Sanchez-Jerez ◽  
Jaume Mora-Vidal ◽  
Dominique Girard ◽  
Alberto Brito
Keyword(s):  
Canary Islands ◽  
Dicentrarchus Labrax ◽  
Sea Bass ◽  
Coastal Habitats

scholarly journals Ambient aerosol concentrations of sugars and sugar-alcohols at four different sites in Norway

2007 ◽  
Vol 7 (16) ◽  
pp. 4267-4279 ◽  
Author(s):  
K. E. Yttri ◽  
C. Dye ◽  
G. Kiss
Keyword(s):  
High Performance ◽  
High Resolution Mass Spectrometry ◽  
Early Summer ◽  
Water Soluble ◽  
Sugar Alcohols ◽  
Ambient Aerosols ◽  
Ambient Aerosol ◽  
Residential Heating ◽  
Spatial And Seasonal Variation ◽  
The Mean

Abstract. Sugars and sugar-alcohols are demonstrated to be important constituents of the ambient aerosol water-soluble organic carbon fraction, and to be tracers for primary biological aerosol particles (PBAP). In the present study, levels of four sugars (fructose, glucose, sucrose, trehalose) and three sugar-alcohols (arabitol, inositol, mannitol) in ambient aerosols have been quantified using a novel HPLC/HRMS-TOF (High Performance Liquid Chromatography in combination with High Resolution Mass Spectrometry – Time of Flight) method to assess the contribution of PBAP to PM>sub>10 and PM2.5. Samples were collected at four sites in Norway at different times of the year in order to reflect the various contributing sources and the spatial and seasonal variation of the selected compounds. Sugars and sugar-alcohols were present at all sites investigated, underlining the ubiquity of these highly polar organic compounds. The highest concentrations were reported for sucrose, reaching a maximum concentration of 320 ng m−3 in PM10 and 55 ng m−3 in PM2.5. The mean concentration of sucrose was up to 10 times higher than fructose, glucose and the dimeric sugar trehalose. The mean concentrations of the sugar-alcohols were typically lower, or equal, to that of the monomeric sugars and trehalose. Peak concentrations of arabitol and mannitol did not exceed 30 ng m−3 in PM10, and for PM2.5 all concentrations were below 6 ng m−3. Sugars and sugar-alcohols were associated primarily with coarse aerosols except during wintertime at the suburban site in Elverum, where a shift towards sub micron aerosols was observed. It is proposed that this shift was due to the intensive use of wood burning for residential heating at this site during winter, confirmed by high concurrent concentrations of levoglucosan. Elevated concentrations of sugars in PM2.5 were observed during spring and early summer at the rural background site Birkenes. It is hypothesized that this was due to ruptured pollen.

scholarly journals Relative Abundance and Diet of Spiny Softshells (Apalone spinifera) in a Lake Erie Population

2017 ◽  
Vol 130 (4) ◽  
pp. 275
Author(s):  
Shannon M Mahoney ◽  
Peter V Lindeman
Keyword(s):  
Relative Abundance ◽  
Lake Erie ◽  
Capture Rate ◽  
Late Summer ◽  
Early Summer ◽  
Fecal Samples ◽  
Turtle Species ◽  
Quagga Mussels ◽  
Mobile Species ◽  
Apalone Spinifera

Populations of the Spiny Softshell (Apalone spinifera) in the Great Lakes are of conservation concern despite being secure elsewhere in their North American range. We examined the relative abundance of Spiny Softshells among the turtle fauna at Presque Isle, a peninsula on the Pennsylvania shoreline of Lake Erie. We also compared male and female diets to determine the presence of invasive Zebra and Quagga Mussels (Dreissena spp.). The Spiny Softshell was the fifth most common of six turtle species captured (2% of captures). in the peninsula’s largest bay there was a significant increase in capture rate and proportion of Spiny Softshell captures in late summer (5% of five species of turtles) compared to early summer (3% of all turtles). Recapture was considerably lower for Spiny Softshells (5%) than for four other turtle species suggesting that either its relative abundance is higher than trapping data indicate or that they are a mobile species with less habitat fidelity than other residents. Prey from fecal samples were quantified using an index of Relative importance (iRi). Males (n = 26) ate primarily unidentified insects (iRi = 59), followed by algal stalks (iRi = 35) and caddisfly larvae (iRi = 4). Females (n = 5) ate primarily algal stalks (iRi = 54), followed by crayfish (iRi = 22) and fish (iRi = 19). only two turtles, one male and one female, passedZebra and Quagga Mussels in fecal samples, thus Spiny Softshells do not appear to make significant use of these invasive molluscs.

Epibiota on vertical and on horizontal surfaces on natural reefs and on artificial structures

2004 ◽  
Vol 84 (6) ◽  
pp. 1117-1130 ◽  
Author(s):  
N.A. Knott ◽  
A.J. Underwood ◽  
M.G. Chapman ◽  
T.M. Glasby
Keyword(s):  
Biological Diversity ◽  
Artificial Structures ◽  
Artificial Structure ◽  
Natural Reef ◽  
Autumn And Winter ◽  
Natural Reefs

Subtidal assemblages of epibiota on vertical and on horizontal surfaces of two natural reefs and two concrete breakwalls were sampled photographically during autumn and winter of 1998. Differences in the assemblages on the two types of substrata (natural reefs and concrete breakwalls) were detected between assemblages on horizontal surfaces, but not on vertical surfaces. The covers of several individual taxa (e.g. Herdmania momus, serpulid polychaetes, coralline encrusting algae) and number of sponge taxa showed clear differences between the two types of substrata. There were great differences between the assemblages on vertical and horizontal surfaces on each natural reef and artificial structure. Invertebrates consistently covered a larger area on vertical than on horizontal surfaces with sponges (as a group) and the ascidian Herdmania momus, the dominant invertebrates on these reefs, clearly showing this pattern. Nevertheless, this pattern was complex for sponges because several species covered a larger area on horizontal than on vertical surfaces and there was no difference in the number of taxa of sponges between the two orientations on natural reefs. Algae, contrary to the results of previous studies, did not show any consistent differences in their covers on vertical or on horizontal surfaces. The results of this study indicated that orientation may be of greater influence on the biological diversity of epibiota on subtidal reefs than whether reefs are natural or artificial.

scholarly journals Spatio-temporal patterns of larval fish settlement in the northwestern Mediterranean Sea

2020 ◽  
Vol 650 ◽  
pp. 153-173
Author(s):  
R Faillettaz ◽  
R Voué ◽  
R Crec’hriou ◽  
LH Garsi ◽  
G Lecaillon ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Fish Assemblages ◽  
Larval Fish ◽  
Early Summer ◽  
Larval Supply ◽  
Coastal Habitats ◽  
Spatial And Temporal Scales ◽  
Nw Mediterranean ◽  
High Quantile ◽  
Nw Mediterranean Sea

Most coastal fish species spend their early life stages in the pelagic environment, before settling in coastal habitats. The variability in the arrival of larvae to coastal habitats provides information on the species’ biology and recruitment potential. To explore the dynamics of larval fish supply to coastal habitats in the NW Mediterranean Sea, 13 sites were monitored using light-traps, from July 2012 to December 2015. Most variation in catches per unit effort (CPUE) among topographic basins and species were statistically significant for high (quantile 75%) and very high (quantile 90%) catches only. At the yearly scale, CPUE displayed strong seasonality, and 3 main species assemblages were detected in late spring-early summer, summer and late autumn-early winter. At the monthly scale, CPUE were higher around the new moon for all quantiles and temporally autocorrelated at a lag of ~28 d. Larval supply also varied spatially with site-specific associations and with riverine influence. Altogether, these results confirm that the previously described patterns of larval supply observed in tropical and subtropical environments (e.g. the high variability at all spatial and temporal scales and the strong influence of the moon) also apply to Mediterranean fish assemblages. Our quantile-based approach demonstrated that the larval supply in the NW Mediterranean Sea is a solid candidate for monitoring the state of the marine ecosystems, highlighting the need to continue such time series.

Annual change in reproductive condition and plasma concentrations of sex steroids in black bream, Acanthopagrus butcheri (Munro) (Sparidae)

1998 ◽  
Vol 49 (5) ◽  
pp. 389 ◽  
Author(s):  
J. A. Haddy ◽  
N. W. Pankhurst
Keyword(s):  
Sex Steroids ◽  
Gonadosomatic Index ◽  
Plasma Concentrations ◽  
Early Morning ◽  
Early Summer ◽  
Hepatosomatic Index ◽  
Black Bream ◽  
One Year ◽  
Gonad Condition ◽  
Acanthopagrus Butcheri

Changes in gonadosomatic index (GSI), hepatosomatic index (HSI), gonad stage and plasma concentrations of sex steroids were studied over one year in black bream (Acanthopagrus butcheri). Black bream have an annual reproductive cycle with a 3-month spawning season in spring–early summer. GSI and HSI values were highest in October and May respectively. Plasma concentrations of oestradiol-17β (E2), testosterone (T) and 17,20β-dihydroxy-4-pregnen-3-one (17,20βP) were highest in females in October. Plasma concentrations of E2 and T were highest in ovulated fish. Concentrations of 17,20βP were higher in fish undergoing final oocyte maturation (FOM) than in fish with regressed gonads. In males, plasma concentrations of T and 11-ketotestosterone (11KT) increased in September and remained elevated until January, but concentrations of 17,20βP did not change with season. However, 17,20βP concentrations in spermiated fish were higher than in non-spermiated fish. Daily changes in gonad condition indicated that females undergo daily cycles of ovarian maturation with ovulation occurring after midday. Plasma T and 17,20βP concentrations of females were elevated at midday in association with FOM, but E2 showed no diel change. In males, partially spermiated fish were dominant in the early morning and fully spermiated fish at midday. Plasma T, 11KT and 17,20βP concentrations were low at midnight and reached maximum levels at 0600 hours.

scholarly journals UV radiation measurements in Marambio, Antarctica during years 2017–2019 in a wider temporal and spatial context

2019 ◽  
Author(s):  
Margit Aun ◽  
Kaisa Lakkala ◽  
Ricardo Sanchez ◽  
Eija Asmi ◽  
Fernando Nollas ◽  
...  
Keyword(s):  
Uv Radiation ◽  
Stratospheric Ozone ◽  
Polar Vortex ◽  
Early Summer ◽  
Uv Index ◽  
Finnish Meteorological Institute ◽  
Time Period ◽  
Temporal And Spatial ◽  
Radiation Measurements

Abstract. In March 2017, ultraviolet (UV) radiation measurements with a multichannel GUV-2511 radiometer were started in Marambio, Antarctica (64.23º S; 56.62º W), by the Finnish Meteorological Institute (FMI) in collaboration with the Argentinian National Meteorological Service (SMN). These measurements were analysed and the results were compared to previous measurements at the same site with NILU-UV radiometer during 2000–2008 and to data from five stations across Antarctica. Measurements in Marambio showed lower UV radiation levels in 2017/2018 compared to those measured during 2000–2008. Also at several other stations in Antarctica the radiation levels were below average in that period. The maximum UV index (UVI) in Marambio was only 6.2, while, during the time period 2000–2008, the maximum was 12. In 2018/2019, the radiation levels were higher than in the previous year and the maximum UVI recorded in Marambio was 9.5. In Marambio, the largest variation of the UV radiation are during the spring and early summer when the stratospheric ozone concentration is at a minimum (the so-called ozone hole). Beside cloud cover, the strength of the polar vortex and the stratospheric ozone depletion are the primary factors that influence the surface UV radiation levels in Antarctica. As the recovery of the ozone layer is slow, the continuation of the measurements is crucial in order to be able to detect long-term changes in UV levels in Antarctica.

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