Martin  A. Hall

Martin  A. Hall
Inter-American Tropical Tuna Commission | IATTC

Ph. D.

About

106
Publications
38,930
Reads
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3,526
Citations
Additional affiliations
January 1984 - February 2021
Inter-American Tropical Tuna Commission
Position
  • Senior Researcher

Publications

Publications (106)
Article
Full-text available
Manta and devil rays (Mobulids) face several immediate threats, including incidental capture in industrial tropical tuna fisheries. As a result, efforts have emerged to avoid or mitigate Mobulid bycatch in these fisheries. However, many mitigation efforts fail to incorporate fisher expertise from the outset, potentially leading to interventions tha...
Article
While there have been recent improvements in reducing bycatch in many fisheries, bycatch remains a threat for numerous species around the globe. Static spatial and temporal closures are used in many places as a tool to reduce bycatch. However, their effectiveness in achieving this goal is uncertain, particularly for highly mobile species. We evalua...
Technical Report
Full-text available
In July 2020, the Conservation Planning Specialist Group (CPSG) of the International Union for Conservation of Nature (IUCN) Species Survival Commission (SSC) was enlisted by the international non-profit sea turtle conservation organization, Upwell, to design and facilitate a two-step decision making process to inform conservation efforts for the C...
Article
Full-text available
The distribution of the spinetail devil ray Mobula mobular in the eastern tropical Atlantic remains poorly known compared to the Pacific and Indian Oceans. We used fisherydependent data and generalized additive models to examine the environmental characteristics associated with the presence of M. mobular in the eastern Atlantic Ocean. Results revea...
Article
Full-text available
Abstract To protect the most vulnerable marine species it is essential to have an understanding of their spatiotemporal distributions. In recent decades, Bayesian statistics have been successfully used to quantify uncertainty surrounding identified areas of interest for bycatch species. However, conventional simulation-based approaches are often co...
Technical Report
Full-text available
The purse-seine FAD fishery is currently the most important way to capture tropical tunas in the EPO. FADs are a very efficient way of fishing; yet, as most fishing methods, they may also have negative effects on species and ecosystems, such as entanglement of sensitive species, contribution to marine debris and pollution or stranding events in vul...
Presentation
Full-text available
Duración del evento: Desde el 11 hasta el 13 de marzo de 2020. Dirección del evento: Facultad de Medicina Veterinaria y Zootecnia - Universidad Autónoma de Sinaloa, Boulevard San Ángel s/n, Culiacán, Sin, México. Esta investigación parte de la descripción de las distribuciones espaciales de las especies de peces picos asociadas a la captura inciden...
Article
Full-text available
In the eastern Pacific Ocean, the tropical tuna purse-seine fishery incidentally captures high numbers of five mobulid bycatch species; all of which are classified as mortalities by the Inter-American Tropical Tuna Commission due to uncertainties in post-release mortality rates. To date, the factors (operational or environmental) leading to the cap...
Presentation
Full-text available
Novena Reunión de Estudiantes de Posgrado de Ciencias Agropecuarias (REPCA 9) Duración del evento: Desde el 27 hasta el 29 de mayo de 2019 Dirección del evento: Facultad de Medicina Veterinaria y Zootecnia - Universidad Autónoma de Sinaloa, Boulevard San Ángel s/n, Culiacán, Sin, México. Esta investigación parte de la descripción de las distribucio...
Conference Paper
Full-text available
The present document aims at summarizing ongoing research on the reduction of impacts of FAD structure on the ecosystem, with special emphasis on the use of biodegradable FADs. This document represents task 2.3 of the FAD WG to inform Annex II of Resolution C-18-05.
Article
This research focuses on the description of the spatial and temporal distributions of mobulid ray species (Mobula birostris, Mobula mobular, Mobula thurstoni, Mobula tarapacana and Mobula munkiana) using data from the observer program (1993–2014) of the Inter-American Tropical Tuna Commission (IATTC). The tuna purse seine operations in the region e...
Article
Full-text available
This research focuses on the description of the spatial and temporal distributions of mobulid ray species (Mobula birostris, Mobula mobular, Mobula thurstoni, Mobula tarapacana and Mobula munkiana) using data from the observer program (1993–2014) of the Inter-American Tropical Tuna Commission (IATTC). The tuna purse seine operations in the region e...
Technical Report
Full-text available
El presente documento resume los resultados de un taller realizado por ISSF para la reducción del impacto de la estructura de los Dispositivos Concentradores de Peces (DCP) en el ecosistema. En este taller se reunieron pescadores y científicos de los 3 océanos para valorar cuál era la situación de partida y tratar de definir cuáles podrían ser las...
Article
Full-text available
Manta and devil rays are filter-feeding elasmobranchs that are found circumglobally in tropical and subtropical waters. Although relatively understudied for most of the Twentieth century, public awareness and scientific research on these species has increased dramatically in recent years. Much of this attention has been in response to targeted fish...
Conference Paper
Full-text available
The use of fish-aggregating devices (FADs) in tropical waters has increased significantly worldwide since the 1990s. Because their extensive use may have implications for the ecosystem, including target and non-target species and habitats, all the tuna regional fisheries management organizations have implemented conservation measures intended to mo...
Article
Full-text available
In terrestrial and coastal systems, the mitigation hierarchy is widely and increasingly used to guide actions to ensure that no net loss of biodiversity ensues from development. We develop a conceptual model which applies this approach to the mitigation of marine megafauna by-catch in fisheries, going from defining an overarching goal with an assoc...
Article
Full-text available
Monitoring and managing fisheries bycatch is increasingly recognized as a critical component of robust fisheries management frameworks. This review, addressing this subject, begins by defining bycatch and analyzing the reasons it happens, from accidental to intentional discarding. It identifies the most common species composing bycatch of the main...
Technical Report
Full-text available
Impact of bycatch caused by cryptic fishing, including ghost fishing by gear lost at sea, is poorly understood. Since the 1980s, purse seine fishers have deployed floating objects at sea, with ten to a hundred meters deep large mesh net panels hanging beneath a floating structure, to aggregate tuna schools. Known as drifting fish aggregating device...
Article
Full-text available
This study examined diversity and habitat characteristics for bycatch assemblages in two different types of fishing (drifting fish aggregating devices sets and sets made on school of tunas) in the eastern Pacific Ocean (20°S–30°N and 70°–150°W) between 2005 and 2011 using biodiversity metrics and Generalized Additive Models. Bycatch information was...
Technical Report
Full-text available
Se describe la pesca de espinel en el Perú. Se presentan datos sobre la comercialización, exportación y volúmenes de descarga de perico o dorado (Coryphaena hippurus), así como la venta de las especies objetivo: perico y tiburón. Se recopiló información de 159 viajes con la participación de 53 embarcaciones diferentes. Asimismo, se resumen los prin...
Technical Report
Full-text available
A workshop on the use of biodegradable FADs, or FADs made with natural materials, was organized by ISSF the 3 rd and 4 th of November of 2016 in the Aquarium of San Sebastian (Spain). This workshop was organized in order to propose solutions to reduce the amount of plastic and other non-natural materials used in FADs to avoid pollution of the ocean...
Article
Full-text available
1. Manta and devil rays of the subfamily Mobulinae (mobulids) are rarely studied, large, pelagic elasmobranchs, with all eight of well-evaluated species listed on the IUCN Red List as threatened or near threatened. 2. Mobulids have life history characteristics (matrotrophic reproduction, extremely low fecundity, and delayed age of first reproductio...
Article
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By-catch species from tropical tuna purse seine fishery have been affected by fishery pressures since the last century; however, the habitat distribution and the climate change impacts on these species are poorly known. With the objective of predicting the potential suitable habitat for a shark (Carcharhinus falciformis) and a teleost (Canthidermis...
Article
Full-text available
In the Eastern Tropical Pacific (ETP), a region of high fishing activity, olive ridley (Lepidochelis olivacea) and other sea turtles are accidentally caught in fishing nets with tuna and other animals. To date, the interaction between fishing activity, ocean conditions and sea turtle incidental catch in the ETP has been described and quantified, bu...
Technical Report
Full-text available
The concept of the Ecosystem Approach has entered the fishery harvesting discussions both from fishery perspectives (Reykjavik Declaration; FAO 2003 Annex to the Code of Conduct and from the principles of the Ecosystem Approach adopted by the CBD in 1995. Both perspectives establish the need to maintain ecosystem structure and functioning, whether...
Conference Paper
Full-text available
I attempt to provide a perspective on some developments around the bycatch problem. The definition of bycatch continues to be an unsettled matter, but for most people it has a clear negative connotation, and I try to reflect that. The options to reduce bycatch are better understood using the components of bycatch estimates: effort and bycatch per u...
Article
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The primary purpose of this document is to 1) provide background on existing data and sources that may be used to develop stock status (or stability) indicators (SSIs) for species taken in the fisheries for tuna and billfishes in the eastern Pacific Ocean (EPO), 2) describe candidate SSIs, and 3) provide a preliminary evaluation of the suitability...
Article
Full-text available
Cryptic, not readily detectable, components of fishing mortality are not routinely accounted for in fisheries management because of a lack of adequate data, and for some components, a lack of accurate estimation methods. Cryptic fishing mortalities can cause adverse ecological effects, are a source of wastage, reduce the sustainability of fishery r...
Book
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This report provides a review of our knowledge of the bycatches, defined as discarded dead, from the tropical tuna purse seine fisheries of the world. The major fishing grounds involved (eastern and western Pacific, eastern Atlantic, and western Indian Oceans) share the gear, the ways of fishing, and the structure of the pelagic communities. Becaus...
Article
Full-text available
Sustainability of living resource exploitation relies on an ecosystem management approach. Within tropical tuna purse seine fisheries using fish aggregating devices (FADs), such an approach incorporates the reduction of bycatch, in particular vulnerable species such as elasmobranchs. The levels of total bycatch (in mass) from fishing operations usi...
Article
Full-text available
The intent of convening the international symposium on circle hooks in research, management, and conservation was to yield a contemporary, science-based assessment of the management and conservation utility of circle hooks in commercial, recreational, and artisanal fisheries around the globe. The symposium objective was to provide a forum for indiv...
Article
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Concern about the impact of fishing on ecosystems and fisheries production is increasing (1, 2). Strategies to reduce these impacts while addressing the growing need for food security (3) include increasing selectivity (1, 2): capturing species, sexes, and sizes in proportions that differ from their occurrence in the ecosystem. Increasing evidence...
Conference Paper
Full-text available
Foreword Since ancient times, fishers have known about the natural tendency of pelagic fish such as tunas, mahi mahi, sharks and marlins to gather around floating objects. Beginning in the early 1980s, fish aggregating devices (FADs) have gradually become essential and preferred tools for tuna fishing around the world. This tech-nique is used at tw...
Article
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The conventional selectivity paradigm is briefly reviewed and its performance examined from an ecosystem perspective. It is stressed that the overall (cumulative) selectivity of the harvest process in an ecosystem is the result of nested selection by fishers and fisheries of: (i) habitats; (ii) species assemblages; (iii) populations and (iv) indivi...
Chapter
Full-text available
The Bycatch Issue Bycatch in the Purse-Seine Fisheries of the Eastern Pacific Ocean Bycatch Examples from the Experience of the Inter-American Tropical Tuna Commission Economic Incentives for Bycatch Reduction Conservation and Management Approaches Concluding Remarks Endnotes References
Article
Full-text available
There is growing evidence that small-scale, coastal, passive net fisheries may be the largest single threat to some sea turtle populations. We review assessments of turtle interactions in these fisheries, and experiments on gear-technology approaches (modifying gear designs, materials and fishing methods) to mitigate turtle by-catch, available from...
Article
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IOTC-2010-WPEB-20 presents the results of a simulation approach conducted to evaluate the biases and uncertainties associated with the use of a ratio estimator method to estimate bycatch in tropical tuna purse seine (PS) fisheries. Simulations were based on a set of observer data collected in the Eastern Pacific Ocean by IATTC in 2000 and focused o...