Examining the utility of alternative video monitoring metrics for indexing reef fish abundance

2014 ◽  
Vol 71 (3) ◽  
pp. 464-471 ◽  
Author(s):  
Zeb H. Schobernd ◽  
Nathan M. Bacheler ◽  
Paul B. Conn
Keyword(s):  
Empirical Study ◽  
Reef Fish ◽  
Video Monitoring ◽  
Fish Populations ◽  
Underwater Video ◽  
Fish Stocks ◽  
Single Frame ◽  
Abundance Indices ◽  
The Mean ◽  
Video Surveys

Underwater video has become an important tool for monitoring reef fish populations worldwide because it is nonextractive and not strongly selective. A variety of approaches have been developed to enumerate fish on videos, but to our knowledge these metrics have not been tested to determine if they are proportional to true abundance. We compared the most commonly used metric, MaxN (i.e., the maximum number of fish in a single frame during the viewing interval), to a newly developed metric, MeanCount (i.e., the mean number of fish observed in a series of snapshots over a viewing interval), using simulations, a laboratory experiment, and an empirical study. MaxN was nonlinearly related to true abundance using all three approaches, providing increasingly dampened estimates of abundance with increasing true abundance (i.e., hyperstability). Therefore, MaxN may result in positively biased indices of abundance for declining fish stocks or negatively biased abundance indices when fish stocks are increasing. Alternatively, MeanCount was generally linearly related to true abundance and its variability was similar to MaxN, suggesting that MeanCount can be useful for indexing abundance of fish in underwater video surveys.

Underwater Video Monitoring of Groupers and the Associated Hard-Bottom Reef Fish Assemblage of North Carolina

2012 ◽  
Vol 88 (1) ◽  
pp. 15-38 ◽  
Author(s):  
Erin J Burge ◽  
James D Atack ◽  
Craig Andrews ◽  
Benjamin M Binder ◽  
Zachery D Hart ◽  
...  
Keyword(s):  
North Carolina ◽  
Reef Fish ◽  
Fish Assemblage ◽  
Video Monitoring ◽  
Underwater Video ◽  
Reef Fish Assemblage

An empirical study for method level refactoring prediction by ensemble technique and SMOTE to improve its efficiency

2021 ◽  
Vol 12 (4) ◽  
pp. 0-0
Keyword(s):  
Empirical Study ◽  
Sampling Techniques ◽  
Ensemble Technique ◽  
Ensemble Techniques ◽  
Functional Attributes ◽  
Code Refactoring ◽  
Optimized Model ◽  
The Mean ◽  
Box Plot ◽  
Prediction Efficiency

Code refactoring is the modification of structure with out altering its functionality. The refactoring task is critical for enhancing the qualities for non-functional attributes, such as efficiency, understandability, reusability, and flexibility. Our research aims to build an optimized model for refactoring prediction at the method level with 7 ensemble techniques and verities of SMOTE techniques. This research has considered 5 open source java projects to investigate the accuracy of our anticipated model, which forecasts refactoring applicants by the use of ensemble techniques (BAG-KNN, BAG-DT, BAG-LOGR, ADABST, EXTC, RANF, GRDBST). Data imbalance issues are handled using 3 sampling techniques (SMOTE, BLSMOTE, SVSMOTE) to improve refactoring prediction efficiency and also focused all features and significant features. The mean accuracy of the classifiers like BAG- DT is 99.53% ,RANF is 99.55%, and EXTC is 99.59. The mean accuracy of the BLSMOTE is 97.21%. The performance of classifiers and sampling techniques are shown in terms of the box-plot diagram.

scholarly journals Indicators of AEI Applied to the Delaware Estuary

2002 ◽  
Vol 2 ◽  
pp. 169-189 ◽  
Author(s):  
Lawrence W. Barnthouse ◽  
Douglas G. Heimbuch ◽  
Vaughn C. Anthony ◽  
Ray W. Hilborn ◽  
Ransom A. Myers
Keyword(s):  
Meta Analysis ◽  
Juvenile Fish ◽  
Fish Populations ◽  
Weight Of Evidence ◽  
Data Sets ◽  
Delaware Estuary ◽  
Fish Stocks ◽  
Trends Analysis ◽  
Definition Of

We evaluated the impacts of entrainment and impingement at the Salem Generating Station on fish populations and communities in the Delaware Estuary. In the absence of an agreed-upon regulatory definition of “adverse environmental impact” (AEI), we developed three independent benchmarks of AEI based on observed or predicted changes that could threaten the sustainability of a population or the integrity of a community.Our benchmarks of AEI included: (1) disruption of the balanced indigenous community of fish in the vicinity of Salem (the “BIC” analysis); (2) a continued downward trend in the abundance of one or more susceptible fish species (the “Trends” analysis); and (3) occurrence of entrainment/impingement mortality sufficient, in combination with fishing mortality, to jeopardize the future sustainability of one or more populations (the “Stock Jeopardy” analysis).The BIC analysis utilized nearly 30 years of species presence/absence data collected in the immediate vicinity of Salem. The Trends analysis examined three independent data sets that document trends in the abundance of juvenile fish throughout the estuary over the past 20 years. The Stock Jeopardy analysis used two different assessment models to quantify potential long-term impacts of entrainment and impingement on susceptible fish populations. For one of these models, the compensatory capacities of the modeled species were quantified through meta-analysis of spawner-recruit data available for several hundred fish stocks.All three analyses indicated that the fish populations and communities of the Delaware Estuary are healthy and show no evidence of an adverse impact due to Salem. Although the specific models and analyses used at Salem are not applicable to every facility, we believe that a weight of evidence approach that evaluates multiple benchmarks of AEI using both retrospective and predictive methods is the best approach for assessing entrainment and impingement impacts at existing facilities.

scholarly journals Trajectories and magnitude of change in coral reef fish populations in Philippine marine reserves: a meta-analysis

Coral Reefs ◽  
2009 ◽  
Vol 28 (4) ◽  
pp. 809-822 ◽  
Author(s):  
R. J. Maliao ◽  
A. T. White ◽  
A. P. Maypa ◽  
R. G. Turingan
Keyword(s):  
Coral Reef ◽  
Reef Fish ◽  
Coral Reef Fish ◽  
Meta Analysis ◽  
Marine Reserves ◽  
Fish Populations

scholarly journals COMMUNITY STRUCTURE AND TROPHIC STATUS OF REEF FISH IN NATUNA WATERS

2020 ◽  
Vol 26 (2) ◽  
pp. 69
Author(s):  
Isa Nagib Edrus ◽  
Pratiwi Lestari
Keyword(s):  
Reef Fish ◽  
Fish Community ◽  
Field Research ◽  
Reef Fishes ◽  
Species Number ◽  
Community Structures ◽  
Underwater Visual Census ◽  
The Mean ◽  
Coral Health ◽  
Density And Biomass

A field research on reef fish-community structures in Natuna waters was carried out in November 2015. This research aimed to obtain the trophic composition of reef fishes and its correlation to diversity, density, and biomass. Underwater visual census on several transect areas was used to collect data. Results show that the identified reef fishes were about 100 species of target-reef fish belonging to 18 families and 23 species of indicator-reef fish of the Chaetodontidae family. The mean species number of target reef fish and indicator reef fish were 42 and 7 species, respectively. The  mean density of the target reef fish and indicator reef fish were 0.4 and 0.05 individual per m2, respectively. The mean of the reef fish relative stock was 0.6 ton/ha. The composition of the herbivores mostly found in the resilient coral reefs r was 46.45 % and the omnivores and planktivores as marketable targeted fishes were 18.64 % and 14.28 %, respectively. The most predominant or major families were from herbivorous, carnivorous, planktivorous, and corallivorous fishes, including Scaridae (i.e. Scarus spp), Lutjanidae (i.e. Lutjanus spp.), Caesionidae (i,e. Caesio cuning and Pterocaesio caerulaurea), and Chaetodontidae (i.e. Chaetodon baronessa and Chaetodon octofasciatus). The results suggested that the community structures were quite prospectively implemented for fisheries; however, it may not be promising for coral resilience. Furthermore, the coral health status was at moderate level in regard to the high numbers of corallivorous butterflyfishes.

Local Replenishment of Coral Reef Fish Populations in a Marine Reserve

Science ◽  
2007 ◽  
Vol 316 (5825) ◽  
pp. 742-744 ◽  
Author(s):  
G. R. Almany ◽  
M. L. Berumen ◽  
S. R. Thorrold ◽  
S. Planes ◽  
G. P. Jones
Keyword(s):  
Coral Reef ◽  
Reef Fish ◽  
Coral Reef Fish ◽  
Marine Reserve ◽  
Fish Populations

Relationships between Verbal and Non-Verbal Abilities for Migrant Children and Australian Children of Low Socio-Economic Status: Similarities and Contrasts

1975 ◽  
Vol 19 (3) ◽  
pp. 209-230 ◽  
Author(s):  
Glen T. Evans ◽  
Millicent E. Poole
Keyword(s):  
Information Processing ◽  
Empirical Study ◽  
Ethnic Groups ◽  
Economic Status ◽  
Migrant Children ◽  
Mental Ability ◽  
Low Ses ◽  
Verbal Abilities ◽  
Socio Economic Status ◽  
The Mean

Previous research indicates that mean patterns of mental ability show striking differences between different ethnic groups. In this paper, some salient features of information processing on which there are likely to be differences between children of Australian born parents of low SES and children of migrant parents are discussed. An empirical study of these differences is described. The mean performance of the migrant children studied compared with children of low SES Australian born parents was found to be related to the balance between verbal and cognitive aspects of the task. The greater the cognitive demand for a given verbal requirement the better the performance of the migrant children relative to the children in the “Australian” group. Further, the intercorrelations between performances were found to be markedly different for the two groups. The results suggest that migrant children in particular may benefit from teaching which emphasises the pragmatic use of language to indicate desired discriminations and concepts.

scholarly journals Fisher behaviour influences catch productivity and selectivity in West Hawaii's aquarium fishery

2011 ◽  
Vol 68 (5) ◽  
pp. 813-822 ◽  
Author(s):  
Todd C. Stevenson ◽  
Brian N. Tissot ◽  
Jan Dierking
Keyword(s):  
Job Satisfaction ◽  
Reef Fish ◽  
Ex Situ ◽  
Catch Per Unit Effort ◽  
Cross Sectional ◽  
Fish Stocks ◽  
Catch Rates ◽  
Fish Trade ◽  
Yellow Tang

Abstract Stevenson, T. C., Tissot, B. N., and Dierking, J. 2011. Fisher behaviour influences catch productivity and selectivity in West Hawaii's aquarium fishery. – ICES Journal of Marine Science, 68: 813–822. In 1999, marine protected areas (MPAs) were implemented along the west coast of the Big Island of Hawaii, closing ∼35% of the coastline to aquarium fishing. Catch per unit effort and total catch of the most commonly targeted fish, yellow tang (Zebrasoma flavescens), have increased since the implementation of the MPAs, yet its abundance has declined by 45% in areas open to aquarium fishing between 1999 and 2007. How effort allocation, harvesting efficiencies, and job satisfaction influence catch productivity and selectivity in West Hawaii's aquarium fishery are investigated, and how these dynamics explain the discrepancy between catch rates and relative abundance for yellow tang is discussed. Cross-sectional fisher questionnaires, semi-structured fisher interviews, and in situ and ex situ catch analyses were performed. The results indicate that fishers dive deeper when reef fish recruitment is perceived as weak, increase harvest efficiency with larger fishing teams, and intensively harvest “coral-friendly” reef fish to supply the global aquarium fish trade. Experienced fishers were less likely to exit the fishery, and job satisfaction was high despite declining fish stocks. These findings may help explain harvesting efficiencies and fleet investment, underscore the importance for evaluating fisher behaviours, and have potential management implications for other aquarium fisheries.

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