scholarly journals Less effort but equal result: Introducing the daily run-size estimation method for quantifying fish passage in fishways

PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0252183
Author(s):  
Mariana O. Côrtes ◽  
Alexandre Peressin ◽  
Alexandre L. Godinho
Keyword(s):  
Temporal Pattern ◽  
Estimation Method ◽  
Fish Passage ◽  
Sampling Time ◽  
Systematic Sampling ◽  
Size Estimation ◽  
Video Images ◽  
Fish Ladder ◽  
Pass Through ◽  
One Year

Determining the number of fish that use a fishway is essential to fisheries management but counting all fish can be impracticable due to labor and cost. We present the daily run-size estimation (DARSE) method, which uses systematic sampling to estimate the number of fish per species that pass through a fishway daily (daily run size, D). The DARSE method makes it possible to determine the minimum fraction of each hour (or hourly samples) of the day necessary to estimate D with known accuracy. We apply DARSE to each of the seven most abundant fish species (other species grouped under ‘Others’) recorded in video images taken during 46 days of one year at the Igarapava Fish Ladder, Brazil. Accuracy in estimating D was influenced by the fraction of the hour sampled and the temporal pattern of fish passage through the fishway. For species with a more uniform temporal pattern of passage, the DARSE method reduced the time spent on sampling by up to 96%, depending on the accuracy used to estimate D. Some of these species required counts of fish that pass in a fraction of an hour for all hours of the day while counts for other species can be done every 2 hours or, more rarely, every 3 hours. For species with a more aggregated temporal pattern of passage, it was possible to estimate D by sampling a fraction of an hour but with reduced accuracy in the estimation of D and little reduction in sampling time.

Query Size Estimation for Joins Using Systematic Sampling

2004 ◽  
Vol 15 (3) ◽  
pp. 237-275 ◽  
Author(s):  
A.H.H. Ngu ◽  
B. Harangsri ◽  
J. Shepherd
Keyword(s):  
Systematic Sampling ◽  
Size Estimation ◽  
Query Size Estimation

scholarly journals Knowledge of breast self-examination in women in Sierra Leone

Curationis ◽  
2007 ◽  
Vol 30 (4) ◽  
Author(s):  
J.H.E.E. Shepherd ◽  
P.A. Mclnerney
Keyword(s):  
Sierra Leone ◽  
Reliability And Validity ◽  
Systematic Sampling ◽  
Screening Methods ◽  
Breast Self Examination ◽  
Data Collection Process ◽  
Specific Objective ◽  
One Year ◽  
Self Examination

This research is a follow up of a Breast Week which was organized in Freetown, Sierra Leone. The specific objective of this study was to assess the effectiveness of the knowledge and teachings given to the women who participated in this project. A quantitative approach with an exploratory descriptive design was adopted and an observational checklist guided the data collection process. A sample size of 120 women (10%) who participated in the Breast Week was obtained through systematic sampling. During the Breast Week women were taught how to examine their breasts using breast self-examination (BSE) to detect abnormalities of the breasts. This study was undertaken one year later by the researcher to ascertain whether the information on breast self-examination provided during the Breast Week was being utilised and whether what was taught was being put into use. Data were analyzed using SPSS version 11.5. Reliability and validity were ensured through the use of a structured observational checklist and a pilot study was undertaken. The observations were all observed and recorded by the same researcher. The majority of the 120 women (91.7%) stated that they had never practiced BSE before the Breast Week. After receiving health education on BSE, 95% were able to demonstrate an effective method of undertaking BSE. It is thus recommended that every opportunity should be utilized in health care settings to teach BSE and to reinforce the practice, especially in poverty stricken countries where other forms of screening methods are unavailable.

scholarly journals Evaluation of fish passage through the Igarapé Dam fish ladder (rio Paraopeba, Brazil), using marking and recapture

2007 ◽  
Vol 5 (2) ◽  
pp. 233-236 ◽  
Author(s):  
Carlos Bernardo Mascarenhas Alves
Keyword(s):  
Power Plant ◽  
Retention Time ◽  
Fish Community ◽  
Thermal Power ◽  
Fish Passage ◽  
Home Ranges ◽  
Community Studies ◽  
Tag Retention ◽  
Fish Ladder ◽  
Pimelodus Maculatus

Rio Paraopeba, a tributary of rio São Francisco, has a six-meter high dam, built in 1978 to divert water to the Igarapé Thermal Power Plant. In 1994, a fish ladder was built at this dam. The results of a marking and recapture program carried out along rio Paraopeba between 1997 and 2001 are described, using information from fish community studies conducted at ten sampling stations between 1994 and 1997. These investigations showed the presence of at least 91 species in the river. During four rainy seasons between 1997 and 2000, fish were caught downstream of the dam, marked with external plastic tags, and immediately released at the same site. The objective was to evaluate fish passage through the ladder, based on recapture information from artisanal and sport fishermen. A total of 3,642 specimens were marked, adding up to a biomass of approximately 1.33 tons. Twenty-six species were used, representing 28.5% of the total recorded richness (91 species). Maximum recorded tag retention time was 10 months. Total recapture rate was 4.37% in four years, reaching 5.75% in the last period (2000-2001). Of all recaptured specimens, 14.0% were caught upstream of the dam, evidencing passage through the ladder. The specimens recaptured upstream of the dam belonged to three species: piau-verdadeiro (Leporinus obtusidens), mandi-amarelo (Pimelodus maculatus) and curimatá-pioa (Prochilodus costatus). These species showed linear home ranges of 15.4, 81.5 and 232.0 km, respectively. Most recaptures occurred immediately downstream of the dam, one of the most intensely fished stretches of rio Paraopeba.

scholarly journals Comparing on site human and video counts at Igarapava fish ladder, south eastern Brazil

2006 ◽  
Vol 4 (2) ◽  
pp. 291-294 ◽  
Author(s):  
Mark D. Bowen ◽  
Simone Marques ◽  
Luiz G. M. Silva ◽  
Volney Vono ◽  
Hugo P. Godinho
Keyword(s):  
Fish Species ◽  
Accurate Method ◽  
Fish Passage ◽  
Southeastern Brazil ◽  
Human Observer ◽  
Full Spectrum ◽  
Prochilodus Lineatus ◽  
Number Of Species ◽  
Fish Ladder ◽  
Number Of Individuals

On site human observations and video images were collected and compared at the window of the Igarapava Dam fish ladder (IDFL), rio Grande , Southeastern Brazil, between March 1st and June 30th, 2004. We conducted four experiments with two humans (Observer 1 and Observer 2) observing fish passage in the IDFL window while a Sony 3CCD video camera (Observer 3) recorded fish passage at the same time. Experiments, each one hour in length, were distributed throughout the diel cycle using full spectrum lights. We identified fish species, the number of individuals for each species, and the real time that they passed. Counts from each human observer were compared to the video counts. The fish species most commonly observed in the window were - curimba (Prochilodus lineatus), mandi-amarelo (Pimelodus maculatus), piau-três-pintas (Leporinus friderici) and ferreirinha (Leporinus octofasciatus). The number of species and individuals were indistinguishable for the three observers. But, the number of species and individuals were significantly different among experiments. Thus, the three observers register the same number of species and count the same number of individuals even when these two response variables differ significantly among experiments. Based on these results, we concluded that the video count was an accurate method to assess fish passage at the IDFL.

scholarly journals Ovarian Histomorphology and Gonadial Cycle of Freshwater Garfish Xenentodon cancila (Hemilton-Buchanan) (Beloniformes:Belonidae)

BIBECHANA ◽  
1970 ◽  
Vol 8 ◽  
pp. 96-104
Author(s):  
Bharat Raj Subba ◽  
Satya Narayan Meheta
Keyword(s):  
Reproductive Cycle ◽  
Oocyte Development ◽  
Fish Pass ◽  
Early Maturing ◽  
Xenentodon Cancila ◽  
Pass Through ◽  
One Year

The histomorphology and gonadial cycle of a freshwater garfish Xenentoton cancila revealed that the ovaries of the fish pass through resting, early maturing advanced maturing, pre-spawning, spawning and spent phases within one year. The oogenetic activity starts in November and continues upto June(GSI=10.19)-July(GSI=11.38), when ovaries are full of yolky eggs. Only young oogonia and oocytes l appeared in September to October. The oocytes of l,ll,lll,lV and V stages were present during November to February. The oocytes Vl and Vll were seen dominated by ripe oocytes during June to late July when spawning takes place. Asychronism mode of oocyte development was recorded in X.cancila. Keywords: Xenentodon cancila; oocyte development; reproductive cycle; spawningDOI: http://dx.doi.org/10.3126/bibechana.v8i0.5694  BIBECHANA 8 (2012) 96-104

scholarly journals Spatio-Temporal Crime Analysis Using KDE and ARIMA Models in the Indian Context

2020 ◽  
Vol 12 (4) ◽  
pp. 1-19
Author(s):  
Prathap Rudra Boppuru ◽  
Ramesha K.
Keyword(s):  
Data Mining ◽  
Predictive Analytics ◽  
Time Series Prediction ◽  
Arima Model ◽  
Estimation Method ◽  
Time Of Day ◽  
Crime Patterns ◽  
Model Time Series ◽  
Spatio Temporal ◽  
One Year

In developing countries like India, crime plays a detrimental role in economic growth and prosperity. With the increase in delinquencies, law enforcement needs to deploy limited resources optimally to protect citizens. Data mining and predictive analytics provide the best options for the same. This paper examines the news feed data collected from various sources regarding crime in India and Bangalore city. The crimes are then classified on the geographic density and the crime patterns such as time of day to identify and visualize the distribution of national and regional crime such as theft, murder, alcoholism, assault, etc. In total, 68 types of crime-related dictionary keywords are classified into six classes based on the news feed data collected for one year. Kernel density estimation method is used to identify the hotspots of crime. With the help of the ARIMA model, time series prediction is performed on the data. The diversity of crime patterns is visualized in a customizable way with the help of a data mining platform.

scholarly journals Mapping of sites in forest stands

2014 ◽  
Vol 86 (4) ◽  
pp. 2025-2038
Author(s):  
SYLVIO PÉLLICO NETTO ◽  
FLAVIO R. STEFANELLO ◽  
ALLAN L. PELISSARI ◽  
HASSAN C. DAVID
Keyword(s):  
Sampling Method ◽  
Total Population ◽  
Pinus Elliottii ◽  
Minimum Variance ◽  
Fixed Number ◽  
Systematic Sampling ◽  
Volumetric Expansion ◽  
Maltese Cross ◽  
One Year

Generally, the forest companies use the total one year planting area as a minimum stratum of the total population and, consequently, the forest inventory processing has been conducted by applying the stratified random sampling to it. This study was carried out in the National Forest of Tres Barras, Brazil, and it aimed to classify and map the sites of Pinus elliottii stands. A systematic sampling was structured into clusters and applied independently by compartments. The clusters, in maltese cross, were composed of four sampling subunits, using Prodan sampling method with a fixed number of six trees. By analysis of the methodology it was possible to confirm the hypothesis: a) the selective thinning cause expressive increase of volumetric variability within compartments; b) the variation of sites within the compartments causes volumetric expansion of variance and this grows proportionally to the quality of the sites; c) the stratification in sites results in minimum variance within them; d) the stratification in sites resulted in until to 91% reduction of variances within them.

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