scholarly journals Detecting anchored fish aggregating devices (AFADs) and estimating use patterns from vessel tracking data in small-scale fisheries

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ahmad Catur Widyatmoko ◽  
Britta Denise Hardesty ◽  
Chris Wilcox
Keyword(s):  
Fisheries Management ◽  
Small Scale ◽  
Tracking Data ◽  
Use Patterns ◽  
Fishing Vessels ◽  
Vessel Tracking ◽  
Large Numbers ◽  
Fish Catch ◽  
Tracking Devices ◽  
Fish Aggregating Devices

AbstractMonitoring the use of anchored fish aggregating devices (AFADs) is essential for effective fisheries management. However, detecting the use of these devices is a significant challenge for fisheries management in Indonesia. These devices are continually deployed at large scales, due to large numbers of users and high failure rates, increasing the difficulty of monitoring AFADs. To address this challenge, tracking devices were attached to 34 handline fishing vessels in Indonesia over a month period each. Given there are an estimated 10,000–50,000 unlicensed AFADs in operation, Indonesian fishing grounds provided an ideal case study location to evaluate whether we could apply spatial modeling approaches to detect AFAD usage and fish catch success. We performed a spatial cluster analysis on tracking data to identify fishing grounds and determine whether AFADs were in use. Interviews with fishers were undertaken to validate these findings. We detected 139 possible AFADs, of which 72 were positively classified as AFADs. Our approach enabled us to estimate AFAD use and sharing by vessels, predict catches, and infer AFAD lifetimes. Key implications from our study include the potential to estimate AFAD densities and deployment rates, and thus compliance with Indonesia regulations, based on vessel tracking data.

scholarly journals KEBIJAKAN RUMPONISASI PERIKANAN PUKAT CINCIN INDONESIA YANG BEROPERASI DI PERAIRAN LAUT LEPAS

2013 ◽  
Vol 5 (2) ◽  
pp. 97
Author(s):  
Duto Nugroho ◽  
Suherman Banon Atmaja
Keyword(s):  
Fisheries Management ◽  
Negative Impact ◽  
Social Dimension ◽  
Potential Conflict ◽  
Fishing Vessels ◽  
Long Run ◽  
Tuna Fisheries ◽  
Tropical Tuna ◽  
Fish Aggregating Devices ◽  
High Seas

<p>Penggunaan rumpon laut-dalam telah mengubah taktik dan strategi perikanan pukat cincin pelagis kecil yang beroperasi di perairan dangkal untuk bergeser pada perikanan tuna neritik tropis. Rumponisasi perikanan pukat cincin yang dirancang untuk meningkatkan produktivitas telah menjadi masalah serius pada perikanan neritik tuna. Hal ini terjadi karena tertangkapnya ikan berukuran kecil dalam jumlah yang dominan sehingga dalam jangka panjang akan berpotensi konflik dengan perikanan lainnya. Para ilmuwan yang tergabung dalam pengelolaan perikanan regional merekomendasikan bahwa pengembangan terkendali terhadap penggunaan rumpon di daerah asuhan juvenile tuna tropis. Pengendalian dalam jangka panjang dapat meminimalkan ancaman bagi kelangsungan hidup kelompok jenis tuna. Hal ini terkait dengan pentingnya memperbesar peluang masuknya sediaan kelompok jenis ini pada tingkat yang layak untuk dimanfaatkan. Di Indonesia, pilihan kebijakan perikanan tangkap baik melalui peralihan sasaran kelompok spesies maupun diversifikasi usaha penangkapan akan selalu bertumpu pada pertimbangan sosial. Bagaimanapun juga, proses mengubah pemahaman nelayan nelalui pengendalian jumlah dan teknologi kapal penangkap ikan serta penutupan sementara daerah penangkapan yang akan melalui proses panjang harus tetap dijalankan untuk mencegah runtuhnya perikanan yang saat ini sedang berjalan.</p><p>The use of Fish Aggregating Devices (FADs) has radically changing the tactic and strategy shallow waters small pelagic purse seiner into high seas tropical neritics tuna fisheries. Applying FADs on purse seine fishery which initiated to increase its productivity became a serious problem to neritics<br />tuna fishery. This indicated by the negative impact on neritics and tropical tuna populations due to large number of small size of tunas being caught and uncertain of number and of FADS position in the high seas. In the long run it will generate a potential conflict to other existing fisheries. The member scientists of regional fisheries management organization (RFMO) recommends that the development of the use of FADs, especially in the area which dominated of juvenile of tropical tuna, should be strongly regulated. FADs management through control system should be applied to minimize impact on recruitment process that associated with the importance of long term availability of its fisheries. Management option through shifting target species and diversification of the fishing activities in<br />Indonesia would always be rely on social dimension. Nevertheles, reorientation on fishers understanding on controllable number of fishing vessels and its technological creeps should strongly be implemented to avoid collapse their existing fisheries.</p>

scholarly journals Use of video monitoring to quantify spatial and temporal patterns in fishing activity across sectors at moored fish aggregating devices off Puerto Rico

2018 ◽  
Vol 82 (2) ◽  
pp. 107 ◽  
Author(s):  
Wessley Merten ◽  
Roberto Rivera ◽  
Richard Appeldoorn ◽  
Kelvin Serrano ◽  
Omar Collazo ◽  
...  
Keyword(s):  
Puerto Rico ◽  
Cost Effective ◽  
Time Of Day ◽  
Small Scale ◽  
Spatial And Temporal Patterns ◽  
Fishing Activity ◽  
Fishing Vessels ◽  
A New Technique ◽  
Associated Species ◽  
Fish Aggregating Devices

A key challenge in small-scale fisheries that use moored fish aggregating devices (mFADs) is the ability to accurately quantify multi-sector fishing activity through fishery-independent methods. Here, we present a novel fishery-independent assessment of multi-sector fishing activity associated with a newly developed open access mFAD programme off San Juan, Puerto Rico. We identified three fishing sectors (recreational, charter and commercial) and 158 individual fishing vessels that routinely operated in the vicinity of the mFADs. The results indicate that daytime fishing activity varied by time of day, day of week, location and sector. During fishing tournaments, the data revealed that fishing activity increased threefold; across monitoring periods, for-hire charter vessels were the most consistent day-to-day user segment, and recreational activity peaked on weekends. Our study represents a new technique for rapidly identifying and detecting multi-sector fishing activity near mFADs and highlights the potential to gather comparable data wherever mFADs are deployed. The results are used to discuss how this technique can be used to assess the performance of mFADs to identify sector overlap and guide management in determining deployment patterns and facilitate the design of cost-effective surveys to estimate mFAD vessel activity, and potentially catch, of mFAD-associated species.

scholarly journals Modelling the impacts of fish aggregating devices (FADs) and fish enhancing devices (FEDs) and their implications for managing small-scale fishery

2014 ◽  
Vol 71 (7) ◽  
pp. 1750-1759 ◽  
Author(s):  
Reniel B. Cabral ◽  
Porfirio M. Aliño ◽  
May T. Lim
Keyword(s):  
Phase Transition ◽  
Mean Field ◽  
Fishing Effort ◽  
Management Tool ◽  
Small Scale ◽  
Limited Area ◽  
Mean Field Model ◽  
Fish Catch ◽  
Fishery Collapse ◽  
Fish Aggregating Devices

Abstract Fish aggregating devices (FADs) are deployed to aggregate fish over a limited area to improve fish catch. Fish enhancing devices (FEDs), which are FADs deployed in no-fishing areas, are fast gaining popularity as a fisheries management tool in the western Pacific. Yet, the impacts of utilizing FADs and FEDs are not yet well understood. In this work, we used a mean-field model to assess the effects of utilizing FADs and FEDs on stock biomass and catch. Our results indicate that using FADs enhances catch per boat when total fishing pressure is low, but can exacerbate fishery collapse when fishing effort is high. On the other hand, a FED-based system can increase the resistance of the fishery to collapse. A FED-based fishery may thus serve as pelagic marine protected areas and/or refugia. In a quota-based system, where fishing time is tied to catch quota, a phase transition occurs: both catch and biomass abruptly shift to low levels without warning. Deploying FADs to act as FEDs in a high quota fishery can prevent this phase transition resulting to a stabilizing effect.

Fishers as foragers: Individual variation among small-scale fishing vessels as revealed by novel tracking technology

2021 ◽  
Vol 238 ◽  
pp. 105896
Author(s):  
Timothy H. Frawley ◽  
Hannah E. Blondin ◽  
Timothy D. White ◽  
Rachel R. Carlson ◽  
Brianna Villalon ◽  
...  
Keyword(s):  
Individual Variation ◽  
Small Scale ◽  
Fishing Vessels ◽  
Tracking Technology

scholarly journals Habitat use patterns of franciscana dolphins (Pontoporia blainvillei) off southern Brazil in relation to water depth

2009 ◽  
Vol 89 (5) ◽  
pp. 943-949 ◽  
Author(s):  
Daniel Danilewicz ◽  
Eduardo R. Secchi ◽  
Paulo H. Ott ◽  
Ignacio B. Moreno ◽  
Manuela Bassoi ◽  
...  
Keyword(s):  
Habitat Use ◽  
Rio Grande ◽  
Limiting Factors ◽  
Small Scale ◽  
Southern Brazil ◽  
Rio Grande Do Sul ◽  
Use Patterns ◽  
Management Procedures ◽  
By Catch ◽  
Pontoporia Blainvillei

The patterns of habitat use by the franciscana dolphins (Pontoporia blainvillei) along its distribution are poorly known. This study investigates the patterns of habitat use with respect to depth for 181 individuals of different age, size, gender and reproductive condition off Rio Grande do Sul, southern Brazil. The results reveal that franciscanas are very homogeneously distributed according to depth. Individuals from all lengths utilize nearly the entire range of depths of the surveyed area. Larger or older animals do not use deeper waters than younger animals, indicating that body size and age are not limiting factors for franciscanas that occupy deeper or offshore waters. Gestation seems to not cause a change in the distribution of females. Although the sex-ratio of the overall data did not vary from 1:1 in different depth intervals, a small-scale comparison between the northern and southern coast demonstrated the existence of some kind of sexual segregation. Franciscana by-catch in Rio Grande do Sul is not sustainable and it is agreed that management procedures are needed. Nevertheless, the available data on species distribution do not allow the designing of a protected area in order to minimize the by-catches of a particular sex/reproductive class.

scholarly journals Secondary use of electronic health record data for clinical workflow analysis

2017 ◽  
Vol 25 (1) ◽  
pp. 40-46 ◽  
Author(s):  
Michelle R Hribar ◽  
Sarah Read-Brown ◽  
Isaac H Goldstein ◽  
Leah G Reznick ◽  
Lorinna Lombardi ◽  
...  
Keyword(s):  
Simulation Models ◽  
Clinical Workflow ◽  
Electronic Health Record Data ◽  
Use Patterns ◽  
Secondary Use ◽  
Timing Data ◽  
Data Files ◽  
Electronic Health ◽  
Tracking Devices ◽  
The Impact

Abstract Objective Outpatient clinics lack guidance for tackling modern efficiency and productivity demands. Workflow studies require large amounts of timing data that are prohibitively expensive to collect through observation or tracking devices. Electronic health records (EHRs) contain a vast amount of timing data – timestamps collected during regular use – that can be mapped to workflow steps. This study validates using EHR timestamp data to predict outpatient ophthalmology clinic workflow timings at Oregon Health and Science University and demonstrates their usefulness in 3 different studies. Materials and Methods Four outpatient ophthalmology clinics were observed to determine their workflows and to time each workflow step. EHR timestamps were mapped to the workflow steps and validated against the observed timings. Results The EHR timestamp analysis produced times that were within 3 min of the observed times for &gt;80% of the appointments. EHR use patterns affected the accuracy of using EHR timestamps to predict workflow times. Discussion EHR timestamps provided a reasonable approximation of workflow and can be used for workflow studies. They can be used to create simulation models, analyze EHR use, and quantify the impact of trainees on workflow. Conclusion The secondary use of EHR timestamp data is a valuable resource for clinical workflow studies. Sample timestamp data files and algorithms for processing them are provided and can be used as a template for more studies in other clinical specialties and settings.

Developing a functional definition of small-scale fisheries in support of marine capture fisheries management in Indonesia

Marine Policy ◽  
2019 ◽  
Vol 100 ◽  
pp. 238-248 ◽  
Author(s):  
Abdul Halim ◽  
Budy Wiryawan ◽  
Neil R. Loneragan ◽  
Adrian Hordyk ◽  
M. Fedi A. Sondita ◽  
...  
Keyword(s):  
Fisheries Management ◽  
Small Scale ◽  
Small Scale Fisheries ◽  
Definition Of

scholarly journals Experimental evaluation of influence of FADs on community structure and fisheries in coastal Kenya

2018 ◽  
Vol 31 ◽  
pp. 6 ◽  
Author(s):  
Emmanuel K. Mbaru ◽  
Dorcas Sigana ◽  
Renison K. Ruwa ◽  
Elizabeth M. Mueni ◽  
Collins K. Ndoro ◽  
...  
Keyword(s):  
Fish Assemblages ◽  
Small Scale ◽  
Catch Per Unit Effort ◽  
Fish Stocks ◽  
Coastal Fisheries ◽  
Small Scale Fisheries ◽  
Open Sea ◽  
Catch Composition ◽  
Structural Indices ◽  
Fish Aggregating Devices

Fish aggregating devices (FADs) have been widely used by commercial fisheries to increase the catchability of pelagic stocks in the open sea. FADs have the potential to enhance nearshore small-scale fisheries where stocks are often overfished. This study examined changes in catch composition, abundance, catch and effort, and aspects of diversity in Kenya's nearshore coastal fisheries after deployment of anchored fish aggregating devices (AFADs). The study combined both fishery independent and dependent methods in assessing changes in fish assemblages post-deployment. Results showed orders of magnitude increase in length, weight, commercial value, and catch per unit effort (CPUE) of landed catch after deployment of FADs suggesting that FADs had a positive effect on the local fishery. Species richness at FAD sites increased post-deployment (n = 281) compared to pre-deployment values (n = 223). Simultaneous use of several complementary structural indices may be required in order to accurately describe and monitor fish assemblages around the FADs. The findings suggest that AFADs are capable of creating both short and long-term impacts on livelihoods, with the potential to deflect pressure on the overfished nearshore fish stocks. However, more research will be needed on redistribution of fish around FADs, design and placement configuration, and site selection amongst others.

Keynote Address

1973 ◽  
Vol 30 (12) ◽  
pp. 1931-1934
Author(s):  
F. E. Popper
Keyword(s):  
Fisheries Management ◽  
Technical Conference ◽  
Keynote Address ◽  
Rate Of Growth ◽  
Efficient Management ◽  
The World ◽  
Management And Development ◽  
The Face ◽  
Fish Catch ◽  
Increasing Demand

The contribution made by Canada in providing the means for the Technical Conference was gratefully acknowledged, and the terms of reference were summarized as approved by Council of the FAO. Briefly, these are — to discuss the scientific and technical means of solving problems and reaching objectives in fisheries management and development. Significant problems that have become evident since the UN Conference in 1955 are: an urgent need for management of most of the traditionally fished stocks; decreasing rate of growth of the world fish catch in the face of increasing demand; economic interactions from greatly intensified fisheries and fishing enterprises; importance of development in relation to management. The need to take the long view in approaching these problems was emphasized, as well as the great value to be derived from recognition of existing deficiencies in organizations or methods. Universally acceptable rules for control of fisheries, and participation by all nations in supplying fisheries data essential for efficient management, are obvious requirements of high priority.

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