Comparison of sonar-, camera- and net-based methods in detecting riverine fish-movement patterns

2018 ◽  
Vol 69 (12) ◽  
pp. 1905 ◽  
Author(s):  
Leonhard Egg ◽  
Joachim Pander ◽  
Melanie Mueller ◽  
Juergen Geist
Keyword(s):  
Species Identification ◽  
Detection Rate ◽  
Small River ◽  
Monitoring Data ◽  
Fish Movement ◽  
Clear Water ◽  
Camera System ◽  
Riverine Fish ◽  
Number Of Individuals ◽  
Fish Monitoring

Monitoring of fish movement is important in understanding and optimising the functionality of fishways and in restoring riverine connectivity. This study compared fish monitoring data (ARIS sonar-based and GoPro camera-based), with catches in a multi-mesh stow net following downstream passage in a small river in Bavaria, Germany. In terms of the number of individuals, the sonar-based system (detection rate=62.6% of net-based catches) outnumbered the counts of the camera-based system (45.4%). Smaller specimens of <100 and <150mm were under-represented with the sonar and the camera-based systems respectively. Species identification based on the camera system was similar to that for net-based catch, whereas no proper species identification could be performed with sonar data. In conclusion, the sonar-based system can be recommended for the counting of fish >100mm during night and turbid conditions, unless species identification is necessary. During daylight and with clear water, cameras can be a cheaper and promising option to monitor species compositions of fish >150mm.

SELECTION AND THE MAINTENANCE OF A COLOUR PATTERN POLYMORPHISM IN THE GREEN SWORDTAIL (XIPHOPHORUS HELLERI)

Behaviour ◽  
2001 ◽  
Vol 138 (4) ◽  
pp. 467-486 ◽  
Author(s):  
Dierk Franck ◽  
Marion Dikomey ◽  
Manfred Schartl
Keyword(s):  
School Choice ◽  
Colour Pattern ◽  
Clear Water ◽  
Variable Environment ◽  
Xiphophorus Helleri ◽  
Black Spots ◽  
Malignant Skin Tumors ◽  
Malignant Skin ◽  
Pattern Polymorphism ◽  
Number Of Individuals

AbstractMany Xiphophorus populations include a number of individuals with black spots on body sides or fins. In many cases such spots are composed of extremely large melanophore cells, the so-called macromelanophores. Macromelanophore pattern polymorphism is known in 10 out of 22 Xiphophorus species. In at least 8 species alleles of the macromelanophore determining locus Mdl are intimately linked to a dominant oncogene, ONC-Xmrk, which can give rise to malignant skin tumors (melanoma). We present, for the first time, evidence that macromelanophore pattern polymorphisms may be maintained by selection in a seasonally variable environment. In school-choice experiments single Xiphophorus helleri females spent more time with groups of spotted females than with non-spotted females under turbid, but not under clear water conditions. Similarly, receptive females preferred spotted males in turbid, but not in clear water. Thus, in nature, when the water becomes turbid after heavy rainfalls, school mates and reproductive partners can evidently find each other more easily with the help of macromelanophore spotting patterns. Intrasexual selection seems to be irrelevant because spotted and non-spotted males were equally successful in competition experiments. A genetic hitchhiking scenario is discussed which could explain the fact that the potentially injurious tumor gene ONC-Xmrk has been maintained in the genus Xiphophorus over a period of millions of years by its close linkage to positively selected macromelanophore alleles.

scholarly journals Fish Monitoring through a Fish Run on the Nakdong River using an Acoustic Camera System

2010 ◽  
Vol 43 (6) ◽  
pp. 735-739 ◽  
Author(s):  
Yong-Su Yang ◽  
Jae-Hyun Bae ◽  
Kyoung-Hoon Lee ◽  
Jung-Su Park ◽  
Byung-Kyu Sohn
Keyword(s):  
Nakdong River ◽  
Camera System ◽  
The Nakdong River ◽  
Fish Monitoring

scholarly journals A novel benchmark for COVID-19 pandemic testing effectiveness enables the accurate prediction of new Intensive Care Unit admissions

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dimitris Nikoloudis ◽  
Dimitrios Kountouras ◽  
Asimina Hiona
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Detection Rate ◽  
Great Accuracy ◽  
Accurate Prediction ◽  
Monitoring Data ◽  
Government Officials ◽  
Testing Data ◽  
Data Point

AbstractThe positivity rate of testing is currently used both as a benchmark of testing adequacy and for assessing the evolution of the COVID-19 pandemic. However, since the former is a prerequisite for the latter, its interpretation is often conflicting. We propose as a benchmark for COVID-19 testing effectiveness a new metric, termed ‘Severity Detection Rate’ (SDR), that represents the daily needs for new Intensive Care Unit (ICU) admissions, per 100 cases detected (t − i) days ago, per 10,000 tests performed (t − i) days ago. Based on the announced COVID-19 monitoring data in Greece from May 2020 until August 2021, we show that beyond a certain threshold of daily tests, SDR reaches a plateau of very low variability that begins to reflect testing adequacy. Due to the stabilization of SDR, it was possible to predict with great accuracy the daily needs for new ICU admissions, 12 days ahead of each testing data point, over a period of 10 months, with Pearson r = 0.98 (p = 10–197), RMSE = 7.16. We strongly believe that this metric will help guide the timely decisions of both scientists and government officials to tackle pandemic spread and prevent ICU overload by setting effective testing requirements for accurate pandemic monitoring. We propose further study of this novel metric with data from more countries to confirm the validity of the current findings.

scholarly journals Detection Rate of Bird Species and What It Depends on: Tips for Field Surveys

2022 ◽  
Vol 9 ◽  
Author(s):  
Federico Morelli ◽  
Vojtěch Brlík ◽  
Yanina Benedetti ◽  
Raphaël Bussière ◽  
Lucie Moudrá ◽  
...  
Keyword(s):  
Body Mass ◽  
Detection Rate ◽  
Bird Species ◽  
Imperfect Detection ◽  
Detection Rates ◽  
Field Surveys ◽  
Species Detection ◽  
Total Species Richness ◽  
Number Of Individuals ◽  
Total Species

Bird counting inevitably suffers from imperfect detection, which varies across species, habitats, period of the day, and seasons. Although various modeling techniques have recently been developed to account for this phenomenon, the biological basis of natural variation in detection remains insufficiently known. This study examined the bird species’ detection rate throughout the day, considering their body mass and diet type, concerning the environment and weather characteristics. Species detection rates were significantly affected by the number of individuals of that species but were unrelated to body mass. Overall, species with the highest detection rate were Corn bunting, Blackbird, European robin, House sparrow and Common chiffchaff. Granivores-insectivores and insectivores showed significant differences in detection rates throughout the day among habitats, with higher detection rates in grasslands during the afternoon. Insectivores showed higher detection rates in farmland during midday (warmest time of the day). Granivores, omnivores and scavengers did not show changes in detection rates in different day periods. Such patterns in daily detection rates were significant even when considering abundance and total species richness in each community. Finally, cloudiness was unrelated to the overall detection rate of birds, while temperature and wind affected detection rates in some guilds. Our findings provide some advice for choosing a suitable ornithological sampling method by considering the avian communities composition in combination with the type of environment, the diet of bird species, and the period of the day.

scholarly journals FORAMINIFERA SEDIMEN DASAR LAUT DELTA MAHAKAM, KALIMANTAN TIMUR

2016 ◽  
Vol 1 (3) ◽  
Author(s):  
Mimin Karmini ◽  
Rostyati Rostyati
Keyword(s):  
Indicator Species ◽  
Planktonic Foraminifera ◽  
River Mouth ◽  
Bottom Current ◽  
Clear Water ◽  
Sea Floor ◽  
Low Salinity ◽  
Neogloboquadrina Dutertrei ◽  
The Common ◽  
Number Of Individuals

Dalam kerangka penelitian dan penyelidikan geologi dan geofisika kelautan yang dilaksanakan oleh tim Pusat Pengembangan Geologi Kelautan, sebanyak 44 percontoh sedimen telah dianalisis foraminiferanya. Pada umumnya, foraminifera plangton yang lebih banyak dijumpai adalah Globigerinoides spp., Neogloboquadrina dutertrei, dan Pulleniatina spp. Neogloboquadrina dutertrei yang dikenal sebagai spesies penciri untuk kondisi salinitas rendah. Spesies-spesies tersebut banyak dijumpai pada kedalaman lebih dari 40 m, dan mencapai maksimum pada kedalaman 1400 m (lokasi 11, lepas pantai Tanjung Bayur). Di tempat seperti ini jumlah individu dan keanekaragaman foraminifera plangton paling tinggi dan termasuk ke dalam zona lereng sesar atas, sedangkan yang terendah ada di lokasi 7 (dekat pantai muara S.Muara Bayur), pada kedalaman 11,3 m. Foraminifera bentosnya yang banyak dijumpai adalah Amphistegina lessonii, Heterolepa spp., Operculina spp., dan Pseudorotalia schroeteriana. Keberadaan Amphistegina lessonii sangat tergantung terhadap intensitas cahaya, air yang jernih, dan biasanya berasosiasi dengan terumbu. Turbulensi di daerah telitian diperkirakan relatif rendah karena banyak dijumpainya spesies tersebut. Jumlah individu tertinggi foraminifera bentos terdapat pada lokasi 35 (Muara Lerong), pada kedalaman 45 m, sedangkan yang terendah ada di lokasi 6 (dekat pantai, muara S.Muara Bayur), pada kedalaman 17,3 m. Keanekaragaman tertinggi dijumpai dilokasi8, pada kedalaman 63,5 m, sedangkan yang terendah di lokasi 6. Fluktuasi jumlah individu foraminifera plangton dan bentos di bagian utara dan tengah tidak terlepas dari kemungkinan adanya arus bawah laut yang bisa mempengaruhi sedimen dan morfologi dasar lautnya. Di bagian selatan jumlah ini cenderung meningkat pada tempat yang menjauh dari pantai. Within the framework of marine geological and geophysical surveyscarried out by the Marine Geological Institute, 44 samples had been analysed, especially for foraminifera. In general, planktonic foraminifera in the study area such as Globigerinoides spp, Neogloboquadrina dutertrei, and Pulleniatina spp are commonly found. Neogloboquadrina dutertrei is known as an indicator species for low salinity. They are found commonly at depths of more than 40 m, the most abundant of it is found at the depth around 1400 m (site 11, offshore of Bayur Peninsula). The maximum total number of individuals and the diversity of planktonic foraminifera occurr at this site as well as at the upper continental, whereas the minimum one is at site 7 (near the mouth of Muara Bayur River), at 11,3 m depth. The common benthonic foraminifera are Amphistegina lessonii, Heterolepa spp., Operculina spp., and Pseudorotalia schroeteriana. Amphistegina lessonii is a species, which is, dependent on light and clear water, and is usually associated with reef. The high number of individuals of this species suggests that the turbulent factor is considered to be relatively low. The maximum total number of individuals of benthonic foraminifera occurs at site 35 (Lerong River Mouth), at 45 m depth, whereas the minimum at site 6 (close to the mouth of Muara Bayur River), at 17,3 m depth. The maximum diversity occursatsite 8, at the depth of 63,5 m, whereas the minimum one is at site 6. The fluctuation of the total number of individuals of planktonic and benthonic foraminifera in the northern and southern parts is probably due to the morphology of the sea floor and the sediment influenced by bottom current. In the southern part the number of individuals of foraminifera tends to increase with the increasing of the distance from the shore.

scholarly journals An efficient benchmark for COVID-19 pandemic testing effectiveness

2021 ◽  
Author(s):  
Dimitris Nikoloudis ◽  
Dimitrios Kountouras ◽  
Asimina Hiona
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Positive Result ◽  
Detection Rate ◽  
Scaling Up ◽  
Great Accuracy ◽  
Monitoring Data ◽  
Viral Spread ◽  
Testing Data ◽  
Second Wave

AbstractTesting for COVID-19 is an important tool that health administrations dispose to adequately monitor and respond to the pandemic, but it is still unclear at which point the number and strategies of testing become effective for these purposes. The percentage of tests that return a positive result is a metric currently used both as a benchmark of testing adequacy and for assessing the viral spread. However, since the former is a prerequisite for the latter, the interpretation is often conflicting, especially during times of testing scaling-up, or during phases of increasing viral spread. We propose as a benchmark for COVID-19 testing effectiveness a simple metric that creates a link between the cases detected and tests performed, with specific observable outcomes that are actively being monitored in most countries, such as the number of new Intensive Care Unit (ICU) admissions and the number of deaths in the community. This new metric, named ‘Severity Detection Rate’, or SDR, represents the current number of daily needs for new ICU admissions, per 100 cases detected (t-i) days ago, per 10,000 tests performed (t-i) days ago. Based on the announced COVID-19 monitoring data in Greece from May 2020 until end of January 2021, we show that beyond a threshold of daily testing number, SDR reaches a plateau of weak variability that begins to reflect testing adequacy. Because of this stabilization, it was possible to predict with great accuracy the daily needs for new ICU admissions, 12 days ahead of each testing data point, over a period of 6 months that included the second wave of the pandemic in the country, with Pearson r = 0.99 (p = 10−180), RMSE = 4,34. We suggest the further study of the metric with data from more countries in order to confirm the proposed functionality and utility.

scholarly journals Selection and application of trophic magnification factors for priority substances to normalize freshwater fish monitoring data under the European Water Framework Directive: a case study

2020 ◽  
Vol 32 (1) ◽  
Author(s):  
Heinz Rüdel ◽  
Verena Kosfeld ◽  
Annette Fliedner ◽  
Georg Radermacher ◽  
Christian Schlechtriem ◽  
...  
Keyword(s):  
Water Framework Directive ◽  
Trophic Level ◽  
Freshwater Ecosystems ◽  
Trophic Levels ◽  
European Water Framework Directive ◽  
Monitoring Data ◽  
Priority Substances ◽  
European Water ◽  
Magnification Factors ◽  
Fish Monitoring

Abstract Background The European Water Framework Directive (WFD) requires the monitoring of biota—preferably fish—to check the compliance of tissue concentrations of priority substances (PS) against substance-specific environmental quality standards (EQSs). In monitoring programs, different fish species are covered, which often are secondary consumers with a trophic level (TL) of about 3. For harmonization, a normalization of monitoring data to a common trophic level is proposed, i.e., TL 4 (predatory fish) in freshwaters, so that data would be sufficiently protective. For normalization, the biomagnification properties of the chemicals can be considered by applying substance-specific trophic magnification factors (TMFs). Alternatively, TL-corrected biomagnification factors (BMFTLs) may be applied. Since it is impractical to derive site-specific TMFs or BMFTLs, often data from literature will be used for normalization. However, available literature values for TMFs and BMFTLs are quite varying. In the present study, the use of literature-derived TMFs and BMFTLs in data normalization is studied more closely. Results An extensive literature evaluation was conducted to identify appropriate TMFs for the WFD PS polybrominated diphenyl ethers (PBDE), hexachlorobenzene, perfluorooctane sulfonate (PFOS), dioxins and dioxin-like compounds (PCDD/F + dl-PCB), hexabromocyclododecane, and mercury. The TMFs eventually derived were applied to PS monitoring data sets of fish from different trophic levels (chub, bream, roach, and perch) from two German rivers. For comparison, PFOS and PBDE data were also normalized using literature-retrieved BMFTLs. Conclusions The evaluation illustrates that published TMFs and BMFTLs for WFD PS are quite variable and the selection of appropriate values for TL 4 normalization can be challenging. The normalized concentrations partly included large uncertainties when considering the range of selected TMFs, but indicated whether an EQS exceedance at TL 4 can be expected. Normalization of the fish monitoring data revealed that levels of substances accumulating in the food web (TMF or BMF > 1) can be underestimated when relying on fish with TL < 4 for EQS compliance assessment. The evaluation also revealed that TMF specifically derived for freshwater ecosystems in Europe would be advantageous. Field-derived BMFTLs seemed to be no appropriate alternative to TMFs, because they can vary even stronger than TMFs.

Chemical Species Identification in an SEM by Changes in Emitted X-Ray Energies

1974 ◽  
Vol 32 ◽  
pp. 570-571
Author(s):  
R. H. Duff
Keyword(s):  
Species Identification ◽  
Valence Electron ◽  
Chemical Species ◽  
X Rays ◽  
Chemical Bonds ◽  
Small Shift ◽  
X Ray ◽  
Electron Transitions ◽  
Peak Energy ◽  
Chemical Combination

A material irradiated with electrons emits x-rays having energies characteristic of the elements present. Chemical combination between elements results in a small shift of the peak energies of these characteristic x-rays because chemical bonds between different elements have different energies. The energy differences of the characteristic x-rays resulting from valence electron transitions can be used to identify the chemical species present and to obtain information about the chemical bond itself. Although these peak-energy shifts have been well known for a number of years, their use for chemical-species identification in small volumes of material was not realized until the development of the electron microprobe.

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