Dirk Zeller

University of Western Australia | UWA · School of Biological Sciences

The exceptional diversity of shallow‐water marine fishes contributes to the nutrition of millions of people worldwide through coastal wild‐capture fisheries, with different species having diverse nutritional profiles. Fishes in ecosystems are reservoirs of micronutrients with benefits to human health. Yet, the amount of micronutrients contained in...

Harmful, capacity-enhancing subsidies distort fishing activities and lead to overfishing and perverse outcomes for food security and conservation. We investigated the provision and spatial distribution of fisheries subsidies in the Indian Ocean. Total fisheries subsidies in the Indian Ocean, estimated at USD 3.2 billion in 2018, were mostly harmful...

The Socotra Archipelago (Yemen), a group of four islands off the north-eastern tip of Africa in the western Indian Ocean, has a population that relies heavily on small-scale fishing for livelihoods and food security. However, the reporting of fisheries catches by Yemen has consistently been incomplete, with artisanal (small-scale, commercial) catch...

Comprehensive catch data are fundamental to support the sustainable management of large pelagic fisheries. However, catch data reported by the Indian Ocean Tuna Commission (IOTC) on behalf of its member countries currently under-represent the extent of these fisheries in the Indian Ocean. We reconstructed fisheries catches of large pelagic species...

Context Contrary to other ocean basins, Indian Ocean catches have increased consistently since 1950, although reported data are known to be incomplete. Fish is a crucial food source in the Indian Ocean; however, ineffective management often empowers over-exploitation. Aims We synthesised and reviewed Indian Ocean reconstructed catch and effort data...

Fisheries stock status is generally based on time series catch and effort data sourced from independent surveys and the fishery. These methods are often expensive and can be limited temporally and spatially. Alternative methods include the use of local fisher knowledge (LFK) to identify observed changes in catch. The blue swimmer crab (Portunus arm...

Tuna Regional Fisheries Management Organizations (RFMOs) are responsible for conservation and sustainable management of transboundary tuna resources in Exclusive Economic Zones and Areas Beyond National Jurisdiction (ABNJ). The data collected and analyses performed by tuna RFMOs are one of the main sources of scientific information supporting the m...

Fishing provides the world with an important component of its food supply, but it also negatively impacts the biodiversity of marine and freshwater ecosystems, especially when industrial fishing is involved. To mitigate these impacts, civil society needs access to fisheries data (i.e., catches and catch-derived indicators of these impacts). Such da...

Most freshwater fisheries occur in developing countries, where freshwater fish underpin local food security and small-scale fisheries livelihoods. Comprehensive catch data are fundamental to support the sustainable management of freshwater fisheries. However, freshwater catch data reported by the Food and Agriculture Organization of the United Nati...

Ocean warming has been affecting marine ecosystems over the past few decades. The signature of ocean warming in global fisheries catch data has been identified through a variety of methods, one of which is the mean temperature of the catch (MTC) index. The MTC is derived from the average temperature preference of fished species weighted by their co...

The Mozambique Channel region in East Africa has diverse marine ecosystems and serves as a migratory corridor for economically important species. Local and foreign industrial fisheries operate in the Mozambique Channel, but regional small-scale fisheries are the crucially important fisheries that provide food security, livelihoods, and economic opp...

In countries like Sierra Leone, where fisheries-independent stock assessments and complex population models are financially and technically challenging, catch statistics can approximate fluctuations in fish stocks where more precise data is not available. However FAO FishStat, the most widely-used time-series data on global fisheries catch landings...

The United States of America, as most other countries, emphasizes commercial fisheries when reporting statistics to the Food and Agriculture Organization of the United Nations (FAO), and excludes data from other sectors, such as recreational fisheries. Our study is a first attempt to account comprehensively for all sources of total U.S. marine catc...

The fisheries of the Arabian Sea Large Marine Ecosystem, which includes the northern part of the western Indian Ocean, from the Horn of Africa to India’s Malabar Coast are described, along with some of the physical parameters impacting on their productivity. The bulk of fishing and thus the majority of catches in the Arabian Sea occur within the ex...

Purpose of review: This review brings together recent key research related to the role of fisheries as a source of nutrients to improve human health and discusses the implications of fisheries policy on food- and nutrient-security. Recent findings: Recent studies highlight the critical role of fisheries to support human nutrition, describing the...

This contribution presents time series of the ‘fishery biomass’ of fish populations, defined as the weight (whole-body, wet weight) of the in-water part of a fishable population, i.e., that part of a population (also called ‘stock’) that is exposed to fishing gears. Detailed data of this type are only available for a limited number of species that...

Fisheries around Africa have historically suffered from the erroneous perception that there is little to no data on or knowledge about these activities, beyond the sometimes questionable or sparse official reported capture statistics. However, concerted efforts by scientists in and associated with Africa have changed this over the last decades. Thi...

The adoption of sovereign blue bonds by the Republic of Seychelles, hereafter referred to as Seychelles, focuses on resource sustainability and illustrates options for island countries to use their ocean resources for years into the future. The fishing industry is one of the main pillars of Seychelles’ economy and is of crucial importance for domes...

Illegal, unreported, and unregulated fishing is widespread; it is therefore likely that illicit trade in marine fish catch is also common worldwide. We combine ecological-economic databases to estimate the magnitude of illicit trade in marine fish catch and its impacts on people. Globally, between 8 and 14 million metric tons of unreported catches...

Small-scale fishing has been an important element of the livelihood and food security in Pacific island countries throughout history; however, such catches have been under-reported in the official fisheries data. Here, we reconstruct the total domestic catches and fishing effort of the Republic of the Marshall Islands (RMI) by fishing sectors for 1...

Commercial fisheries catches by country are documented since 1950 by the Food and Agriculture Organization (FAO). Unfortunately, this does not hold for marine recreational catches, of which only few, if any, estimates are reported to FAO. We reconstructed preliminary estimates of likely marine recreational catches for 1950–2014, based on independen...

Despite worldwide demand for tuna products and considerable conservation interest by civil society, no single global dataset exists capturing the spatial extent of all catches from fisheries for large pelagic species across all ocean basins. Efforts to spatially quantify the historical catch of global tuna fisheries have been restricted to the few...

Using the Sea Around Us global catch and effort databases (www.seaaroundus.org), this study presents time series estimates (1950–2016) of total CO2 emissions and emissions intensity (CO2 emissions per unit of catch) from the combustion of fuel in global marine fisheries by fishing sector, as well as a regional comparison of fuel use intensity for 2...

Declining fisheries catches are a global trend, with management failing to keep pace with growth in fishing effort and technological advances. The economic value of Honduras’ catches was estimated within the industrial and artisanal sectors. Catches were found to be 2.9 times greater than the official statistics between 1950 and 2015. The merging o...

There are currently two separate approaches for estimating global CO 2 emissions from marine fishing. One approach uses catch-based fuel use intensity (FUI) estimates for well-studied areas/fisheries to estimate FUI in data poor regions. The second approach, effort-based FUI, uses reconstructed fishing effort data to estimate fuel use based on vess...

We present a view on global marine fisheries that emphasizes mitigating the conflict between sustainability and the scale of industrial exploitation driven by the demand of continuous economic growth. We then summarize the current state of global fisheries. Finally, we advocate strongly for scaling back industrial fisheries, most of which are non-s...

Tokelau is among the most vulnerable countries to climate change from both an environmental and economic perspective, whilst being highly dependent on marine resources for dietary nutrition. Industrial as well as small-scale fisheries are present in Tokelau’s waters, with Tokelau itself only participating in small-scale fisheries. Industrial fisher...

The last three bi-annual State of World Fisheries and Aquaculture (SOFIA) reports by the Food and Agriculture Organization of the United Nations (FAO) gave the impression that they downplayed the stark reality of declining trends in global marine fisheries catches. In contrast, the most recent SOFIA 2018 deserves praise for seemingly striking a dif...

A third of global fish stocks are overexploited and many are economically underperforming, resulting in potential unrealized net economic benefits of USD 51 to 83 billion annually. However, this aggregate view, while useful for global policy discussion, may obscure the view for those actors who engage at a regional level. Therefore, we develop a me...

Scenario analysis for north-central and southern anchoveta stocks of Peru. (DOCX)

Average attained landings for 2011–2015 (103 t), modeled higher landings (103 t) based on Optimal F, and their impact on revenue and profits (USD 106). (DOCX)

Supplemental methods. (DOCX)

Supplementary data. (XLSX)

Cost of fishing and ex-vessel prices by fishery (USD·tonne-1). (DOCX)

Estimated landings (103 t) by company for the US menhaden fishery. (DOCX)

Landings (103 t) by company by year for the Peruvian anchoveta fishery based on quota ownership. (DOCX)

Marine fisheries are in crisis, requiring twice the fishing effort of the 1950s to catch the same quantity of fish, and with many fleets operating beyond economic or ecological sustainability. A possible consequence of diminishing returns in this race to fish is serious labour abuses, including modern slavery, which exploit vulnerable workers to re...

The interaction between fishing gears and the marine environment define 'fisheries,' and the effect of gears on marine ecosystems and fish stocks has been the source of much debate. Here, we present the first summary of globally reconstructed fisheries catches by major gear categories for 1950-2014. We used the Sea Around Us reconstructed global ca...

The management of marine living resources that straddle country borders has historically been a challenge, particularly in cases where political tensions are high. The jointly managed fisheries resources in the Barents Sea are a notable exception, wherein the Russian Federation (formerly Soviet Union) and Norway have relatively successfully managed...

Postwar growth of industrial fisheries catch to its peak in 1996 was driven by increasing fleet capacity and geographical expansion. An investigation of the latter, using spatially allocated reconstructed catch data to quantify “mean distance to fishing grounds,” found global trends to be dominated by the expansion histories of a small number of di...

While the ecological impacts of fishing the waters beyond national jurisdiction (the “high seas”) have been widely studied, the economic rationale is more difficult to ascertain because of scarce data on the costs and revenues of the fleets that fish there. Newly compiled satellite data and machine learning now allow us to track individual fishing...

Climate change-reflected in significant environmental changes such as warming, sea level rise, shifts in salinity, oxygen and other ocean conditions-is expected to impact marine organisms and associated fisheries. This study provides an assessment of the potential impacts on, and the vulnerability of, marine biodiversity and fisheries catches in th...

Climate change–reflected in significant environmental changes such as warming, sea level rise, shifts in salinity, oxygen and other ocean conditions–is expected to impact marine organisms and associated fisheries. This study provides an assessment of the potential impacts on, and the vulnerability of, marine biodiversity and fisheries catches in th...

Vulnerability indicators: Exposure, sensitivity and adaptive capacity. (DOCX)

Top 47 species important to fisheries in the region. Species are ordered by average catch size (tonnes). (DOCX)

Average annual total catch (in tonnes), Gulf catch (in tonnes) and proportion the latter represents overall by country. (DOCX)

Vulnerability of charismatic species to climate change impacts. (DOCX)

Map of occurrence records for the 55 species that were modelled in the world’s oceans, including the Gulf. Source: Natural Earth version 4.0.0 - http://www.naturalearthdata.com/. Figure created using MATLAB. (TIF)

Characteristics of all the priority marine species in the Gulf (ordered alphabetically) as obtained from FishBase [44], SeaLifeBase [45] and IUCN red list of threatened species [106]. TL–Trophic level. CR–Critically Endangered, EN–Endangered, VU–Vulnerable, NT–Near Threatened, LC–Least Concern, Data Deficient, NE–Not Evaluated. (DOCX)

Percent change in habitat suitability forall non-fish species in the Economic Exclusive Zones (EEZs) of the Gulf in 2090. Results are presented for the RCP 8.5 scenario and as average of the three niche models (BIOCLIM, NPPEN and ENFA). The error bars represent inter-model range. (TIF)

Fishery catch reconstruction for the Gulf. (DOCX)

The bias in catch time series data that occurs when improvements in fisheries catch reporting systems (e.g., consideration of a previously unmonitored fishery, or region) lead to an increase in current catches without the corresponding past catches being corrected retroactively, here called ‘presentist bias’ is described, and two examples, pertaini...

The Somali region, at the Horn of Africa, has experienced a high degree of political and social instability at various times since 1950, through various regimes and an extended period of a lack of national government institutions during civil war. This study documents and extends prior reconstructions of domestic and foreign fisheries catch data fo...

Overexploitation of marine resources has led to declining catches in many countries worldwide, and often also leads to fishing effort being exported to waters of neighboring countries or high seas areas. Thailand is currently under pressure to curb illegal fishing and human rights violations within its distant water fleets or face a European Union...

For many small island nations, fisheries provide residents with both food security and economic stability. However, in order to create effective and sustainable fisheries policies and management that will ensure a growing population can prosper, policy makers need to know what is being fished and how much is fished. Vanuatu, the smallest country in...

The remote Pitcairn Island Group in the South Pacific was designated one of the world's largest marine reserves in 2016, encompassing some of the few remaining near-pristine areas within EEZ boundaries. Pitcairn's domestic fisheries are small-scale, and consist mainly of subsistence (non-commercial) and limited artisanal (commercial) catches. There...

In countries like Sierra Leone, where stock assessments based on fisheries-independent data and complex population models are financially and technically challenging, catch statistics may be used to infer fluctuations in fish stocks where more precise data are not available. However, FAO FishStat, the most widely-used time-series data on global fis...

The marine fisheries catches of Malta were reconstructed for the period 1950-2014, including for reported and previously unreported commercial large- and small-scale catches, unmonitored fisheries catches, i.e., subsistence and recreational fisheries, as well as major discards. The present study updates and improves a previous catch reconstruction...

As part of the global marine fisheries catch reconstruction project conducted by the Sea Around Us over the last decade, estimates were derived for discards in all major fisheries in the world. The reconstruction process derives conservative but non-zero time-series estimates for every fisheries component known to exist, and relies on a wide variet...

This study presents a reconstruction of the total catch of Bulgarian marine fisheries in the Bulgarian Exclusive Economic Zone for the time period 1950–2013, including previously unreported landings, discards, recreational and subsistence catches. The landings data officially reported by Bulgaria to the Food and Agriculture Organization of the Unit...

Comments are provided on several points in the 2016 State of the World Fisheries and Aquaculture produced by the Food and Agriculture Organization of the United Nations (FAO). It is shown that data assembled by FAO from submissions by countries suggest a “stable” trend mainly because the declining catches of a number of countries with reliable stat...