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Substitution of inland fisheries with aquaculture and chicken undermines human nutrition in the Peruvian Amazon

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With declining capture fisheries production, maintaining nutrient supplies largely hinges on substituting wild fish with economically comparable farmed animals. Although such transitions are increasingly commonplace across global inland and coastal communities, their nutritional consequences are unknown. Here, using human demographic and health information, and fish nutrient composition data from the Peruvian Amazon, we show that substituting wild inland fisheries with chicken and aquaculture has the potential to exacerbate iron deficiencies and limit essential fatty acid supplies in a region already experiencing high prevalence of anaemia and malnutrition. Substituting wild fish with chicken, however, can increase zinc and protein supplies. Chicken and aquaculture production also increase greenhouse gas emissions, agricultural land use and eutrophication. Thus, policies that enable access to wild fisheries and their sustainable management while improving the quality, diversity and environmental impacts of farmed species will be instrumental in ensuring healthy and sustainable food systems.
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Articles
https://doi.org/10.1038/s43016-021-00242-8
1Ecology, Evolution and Environmental Biology, Columbia University, New York, NY, USA. 2Department of Natural Resources and the Environment, Cornell
University, Ithaca, NY, USA. 3Population Medicine and Diagnostic Sciences, Cornell University, Ithaca, NY, USA. 4Independent researcher, Florahome, FL,
USA. 5Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, USA. 6Wildlife Conservation Society, Iquitos, Peru. 7US Geological Survey,
New York Cooperative Fish and Wildlife Research Unit, Department of Natural Resources and the Environment, Cornell University, Ithaca, NY, USA.
e-mail: s.heilpern@cornell.edu
Increasing food security while minimizing environmental deg-
radation is one of the greatest sustainability challenges facing
humanity1. Fisheries are at the centre of this challenge for their
role in both transforming aquatic ecosystems and in providing mil-
lions of people across the world with a major source of key macro-
and micronutrients2. Yet fish catch is stagnating and many of the
world’s fisheries are exploited beyond sustainable levels3. Strategies
to supplement the contribution of fisheries to population nutri-
tion partially hinge on finding substitutes for wild fish, particularly
with economically comparable animal foods, such as farm-raised
fish and chicken4,5. Animal production farming, however, is most
often characterized by low species diversity cultivated for their eco-
nomic rather than their nutritional potential6. Furthermore, farmed
species contribute to greenhouse gas emissions, eutrophication of
waterways and land conversion7. Although the environmental costs
of farmed foods are well established1,8, the nutritional implications
of substituting wild fisheries with farmed species, such as chicken
and aquaculture, have not been widely quantified.
Here we analyse the nutritional consequences of substituting
wild inland fish with chicken and aquaculture in Loreto, in the
Peruvian Amazon. As in many other inland and coastal regions,
Loreto’s population is heavily dependent on diverse capture fisher-
ies but is rapidly transitioning to a less diverse set of farmed animal
foods. This transition is concentrated on chicken and aquaculture
species, which are considered less financially and environmentally
costly than other farmed animals such as livestock7. Wild fish har-
vests in Loreto have remained relatively constant but are showing
signs of overexploitation9. In contrast, between 2010 and 2016,
chicken production increased from 19,628 to 32,671 t, and aqua-
culture from 642 to 1,136 t10,11. These patterns reflect global trends,
where growth in chicken and aquaculture production has outpaced
that of capture fisheries, particularly in developing countries12.
Further mirroring these global patterns, aquaculture production
in Loreto is low diversity, with four species (Prochilodus nigricans,
Brycon sp., Colossoma macropomum and Arapaima gigas) account-
ing for over 98% of regional farmed fish production. Although
expanding chicken and aquaculture production is driven by myriad
factors, including human population growth, shifting dietary pref-
erences and stagnating wild fish production, governmental policies
in particular, typically supported by multilateral institutions, such
as the World Bank, are incentivizing dietary shifts from wild fish
to chicken and aquaculture13. Although these policies are often
designed to mitigate food insecurity, whether these alternatives to
wild fish undermine or support nutrition has yet to be determined.
Using human demographic and health information, and animal
nutrient composition data from Loreto (Supplementary Data 1), we
examined the nutritional overlap between wild and common farm
species, and employed simulation models to estimate how substi-
tuting wild fish with chicken and aquaculture affects the supply
of animal-derived nutrients to Loreto’s urban population (that is,
protein, iron, zinc, calcium and omega-3 fatty acids—α-linolenic
acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic
acid (DHA)). Nutrient supplies were estimated as the number of
people, scaled to Loretos population age structure, meeting their
annual reference nutrient intakes (RNIs), or the amount required to
ensure nutritional needs are met for a given nutrient as established
by the World Health Organization14. In Loreto, 43.3% of children
under 5 yr are iron deficient and 25.3% are chronically malnour-
ished, or stunted; and 22.4% of women of reproductive age are iron
deficient15. Thus, beyond considering how adjustments to food sup-
ply might exacerbate existing nutritional gaps, we further discuss
our results in the context of other environmental and food security
Substitution of inland fisheries with aquaculture
and chicken undermines human nutrition in the
Peruvian Amazon
Sebastian A. Heilpern 1,2 ✉ , Kathryn Fiorella 3, Carlos Cañas 4, Alexander S. Flecker5, Luis Moya6,
Shahid Naeem1, Suresh A. Sethi 7, Maria Uriarte1 and Ruth DeFries1
With declining capture fisheries production, maintaining nutrient supplies largely hinges on substituting wild fish with econom-
ically comparable farmed animals. Although such transitions are increasingly commonplace across global inland and coastal
communities, their nutritional consequences are unknown. Here, using human demographic and health information, and fish
nutrient composition data from the Peruvian Amazon, we show that substituting wild inland fisheries with chicken and aqua-
culture has the potential to exacerbate iron deficiencies and limit essential fatty acid supplies in a region already experiencing
high prevalence of anaemia and malnutrition. Substituting wild fish with chicken, however, can increase zinc and protein sup-
plies. Chicken and aquaculture production also increase greenhouse gas emissions, agricultural land use and eutrophication.
Thus, policies that enable access to wild fisheries and their sustainable management while improving the quality, diversity and
environmental impacts of farmed species will be instrumental in ensuring healthy and sustainable food systems.
NATURE FOOD | VOL 2 | MARCH 2021 | 192–197 | www.nature.com/natfood
192
Content courtesy of Springer Nature, terms of use apply. Rights reserved
... It also has low labor demands, and stable prices, making it useful in the portfolio strategy of households, and a part of the more general allure of this sector for large holders as well. Demand for beef is strong in Brazil, unlike Peru where beef is not as widely consumed, and where poultry consumption is growing exponentially (Heilpern et al. 2021;Kovalskys et al. 2019). ...
... Aquaculture's rapid expansion in the Amazon holds the potential to provide an alternative to cattle production, helping diversify local incomes and rural and urban food supplies while reducing the land footprint of animal-based foods (McGrath et al. 2020). However, the degree to which aquaculture will become an environmentally sustainable, nutritious, and equitable component of Amazonian food systems depends on myriad factors, including improving production efficiency, culturing a diverse set of native species, reducing initial investment costs, and ensuring that farmed fish are accessible to people who rely heavily on fish, including rural, poor and Indigenous people (Heilpern et al. 2021). While much uncertainty remains around the tradeoffs between aquaculture, capture fisheries, cattle and other animal-sourced foods, it is clear that well-managed fisheries, both wild and farmed, could continue to be a culturally relevant and sustainable component of the Amazon's future bioeconomy (see Chapter 30). ...
Chapter
Full-text available
Finding pathways to more sustainable agriculture and resource use remains the most pressing challenge for Amazonian countries today. This chapter focuses on characterizing recent changes in the structure and types of agrarian production systems, including fisheries. The chapter identifies local responses to deal with both the challenges and opportunities to promote more sustainable production and extraction economies in the Amazon. While regional agriculture and resource economies rest on a rich diversity of producers, knowledge, and production systems, the expansion of agribusiness enterprises came to dominate the distribution of subsidies, institutional support, and logistical infrastructure. These trends are associated with forest loss and degradation, pollution of waterways, pressures on and/or displacement of Indigenous and rural communities, and increased greenhouse gas emissions, all of which undermine an array of ecosystem services. The impacts of socio-economic and hydro-climatic changes on livelihoods, environments and biodiversity are very diverse and complex in each one of the Amazonian countries and within them. In this chapter, we provide an in-depth quantitative case study focusing on the Brazilian Amazon, including attention to changes in key agrarian production systems (agricultural crops, cattle raising, agroforestry, and tree plantations). The chapter uses comparable agrarian census data from 1995, 2006, and 2017. The quantitative analysis is complemented by qualitative and empirically grounded discussions that provide insights into the changes and impacts of different activities, how they are interlinked, and how they differ across Amazonian countries. The final section provides recommendation towards promoting adaptive, profitable, and more sustainable smallholder production and management systems that reduce deforestation and support local communities and economies, in the context of increasing urbanization and climate change.
... The Amazon is one of the most productive and diverse freshwater ecosystems on the planet [1], and has among the highest rates of fish consumption in the world [6]. While vast portions of the region remain sparsely occupied, growing urban demand for fish has resulted in the overexploitation of key species [7,8]. ...
Article
Inland fisheries feed greater than 150 million people globally, yet their status is rarely assessed due to their socio-ecological complexity and pervasive lack of data. Here, we leverage an unprecedented landings time series from the Amazon, Earth's largest river basin, together with theoretical food web models to examine (i) taxonomic and trait-based signatures of exploitation in inland fish landings and (ii) implications of changing biodiversity for fisheries resilience. In both landings time series and theory, we find that multi-species exploitation of diverse inland fisheries results in a hump-shaped landings evenness curve. Along this trajectory, abundant and large species are sequentially replaced with faster growing and smaller species. Further theoretical analysis indicates that harvests can be maintained for a period of time but that continued biodiversity depletion reduces the pool of compensating species and consequently diminishes fisheries resilience. Critically, higher fisheries biodiversity can delay fishery collapse. Although existing landings data provide an incomplete snapshot of long-term dynamics, our results suggest that multi-species exploitation is affecting freshwater biodiversity and eroding fisheries resilience in the Amazon. More broadly, we conclude that trends in landings evenness could characterize multi-species fisheries development and aid in assessing their sustainability.
... Restoring fisheries and curbing overfishing Fish provide millions of people in the Amazon, from Indigenous peoples to urban populations, with their primary source of protein, omega-3s, and other essential nutrients 70,71 . Restoring fisheries involves, in part, addressing overfishing through the development and enforcement of sustainable fishing practices and regulations, including trait-based regulations, restoring and protecting critical habitats, and improved monitoring. ...
Chapter
Full-text available
Key Messages & Recommendations 1) Restoration encompasses a broad suite of objectives related to the practice of recovering biodiversity and ecosystem functions and services, such as water quality, carbon sequestration, and peoples' livelihoods. It spans aquatic and terrestrial realms, and goes beyond natural ecosystems to include the recovery of socially-just economic activities on deforested lands. 2) Within terrestrial systems, site-specific restoration options include speeding up recovery after mining, reforesting the vast swathes of defor-ested land, facilitating the recovery of degraded primary forests, and the restoration of sustainable economic activities in deforested lands via sustainable intensification, agroforestry, or improving farm-fallow systems. 3) Restoring aquatic systems requires applying techniques to remediate polluted aquatic and terrestrial habitats, including those affected by min-a (Rio Branco/Porto Velho), Rio Branco AC 69900-970, Brazil ing, petroleum, and plastic; developing and enforcing rules to reinstate natural flow regimes; removing barriers that fragment rivers and disrupt connectivity, and implementing collabora-tive partnerships to recover fisheries and flood-plain habitats. 4) The high cost and complexity of many restoration options mean they should only be used as a last resort; for vast areas of the Amazon, the primary aim should be to avoid the need for future restoration by conserving forests and waterbodies. Abstract This chapter examines site-specific opportunities and approaches to restore terrestrial and aquatic systems, focusing on the local actions and benefits. Landscape and biome-wide considerations are addressed in Chapter 29.
... Fish provide millions of people in the Amazon, from Indigenous peoples to urban populations, with their primary source of protein, omega-3s, and other essential nutrients (Heilpern et al., 2021;Isaac and De Almeida, 2011). Although there are many commercially viable species, the largest and most important fisheries are based on a subset of about 10-18 species groups found in and around the productive floodplains and estuaries . ...
Technical Report
Full-text available
This chapter examines site-specific opportunities and approaches for restoring terrestrial and aquatic systems, focusing on local actions and their immediate benefits. Landscape, catchment, and biome-wide considerations are addressed in Chapter 29. Conservation approaches are addressed in Chapter 27.
Chapter
Full-text available
This Report provides a comprehensive, objective, open, transparent, systematic, and rigorous scientific assessment of the state of the Amazon’s ecosystems, current trends, and their implications for the long-term well-being of the region, as well as opportunities and policy relevant options for conservation and sustainable development.
Chapter
Full-text available
This Report provides a comprehensive, objective, open, transparent, systematic, and rigorous scientific assessment of the state of the Amazon’s ecosystems, current trends, and their implications for the long-term well-being of the region, as well as opportunities and policy relevant options for conservation and sustainable development.
Chapter
Forests and aquatic ecosystems are the basis for ecosystem services, which play a crucial role in people’s livelihoods, human well-being, and health. Some of the most relevant and challenging current health problems in Amazonia are associated with deforestation and degradation of terrestrial and aquatic ecosystems, including the risk of contracting infectious diseases, respiratory and cardiovascular problems caused by exposure to smoke from forest fires, and mercury (Hg) contamination due to mining and other deforestation and biomass burning practices. Emergent, re-emergent, and endemic infectious diseases in the Amazon have all been associated with environmental changes driven by rapid human population growth and/or socioeconomic transition. Yet the relationship between forest conversion and fragmentation and the incidence of infectious disease is complex, scale-dependent, and heavily modulated by socioecological feedbacks. Amazonia is also a region of exceptionally high (yet poorly known) diversity of viruses and viral hosts, exacerbating the risks of potential zoonotic spillovers. Another major environmental and public health concern in the Amazon basin is mercury contamination resulting from gold mining, hydropower dams, deforestation, and petroleum extraction. Not only are Amazon basin communities exposed to high Hg concentrations at risk of toxicological contamination, but environmental effects on water resources, fisheries and wildlife are seen throughout Amazonian ecosystems. As a result, communities with high levels of fish consumption present some of the world’s highest recorded Hg levels. The impact of fires are also a big concern, since they emit large quantities of particulate matter and other pollutants that degrade air quality and affect human health, especially among vulnerable groups in the Amazon. Here we demonstrate that environmental degradation is also a socio-economic issue, affecting the health of millions of Amazonians and compromises the quality of life and human health of future generations.
Chapter
Full-text available
This chapter presents country-specific descriptions of human intervention in the Amazon. In general, a rapid expansion of agricultural and extractive activities, mostly for export but also for domestic markets, and to a lesser degree small scale agriculture, have led to extensive deforestation and environmental degradation without substantially improving the living conditions of the population. Government policies and the extent of State ascendancy in the area also seem to be a powerful determinant of the nature and scale of the process. Despite the common underlying international and domestic economic and political forces in the Amazon, each country has its own particularities. In the case of Colombia, the process was shaped by the guerilla presence and deteriorated after the Peace Treaty, which does not mention “deforestation” and perpetuates Colombia’s extractivist model. Ecuador’s case is representative of the link between fossil fuel extraction, environmental deterioration, and social exclusion. The case of Peru shows an Amazon perceived as a territory awaiting to be “conquered, occupied, and exploited”, subjected to an unwavering extractive and market-orientated drive. In Bolivia, contradictions between conservation and state-led development policies and business activities, which have transformed it into the second deforestation hotspot of Amazonia after Brazil, are presented. The Venezuelan Amazon is subject to rampant violence and illegal activity driven by the political geography of gold in mixed configurations of governance, with blurred boundaries between legality and illegality and prevailing negligence concerning conservation. The Guianas share low deforestation levels and lower environmental pressures, but the recent expansion of gold mining poses a serious threat. The Brazilian case presented in the previous Chapter is referenced here when comparing countries’ experienes. Conservation experiences are also included. In all cases, unsustainable extractivist models have outpaced conservation policies; however, these experiences can prove useful in the design of effective conservation policies, reduction of greenhouse gas emissions, and improvements in living conditions of Indigenous peoples and local communities.
Book
Full-text available
The Science Panel for the Amazon (SPA) is an unprecedented initiative convened under the auspices of the United Nations Sustainable Development Solutions Network (SDSN). The SPA is composed of over 200 preeminent scientists and researchers from the eight Amazonian countries, French Guiana, and global partners. These experts came together to debate, analyze, and assemble the accumulated knowledge of the scientific community, Indigenous peoples, and other stakeholders that live and work in the Amazon. The Panel is inspired by the Leticia Pact for the Amazon. This is a first-of-its-kind Report which provides a comprehensive, objective, open, transparent, systematic, and rigorous scientific assessment of the state of the Amazon’s ecosystems, current trends, and their implications for the long-term well-being of the region, as well as opportunities and policy relevant options for conservation and sustainable development. The three volumes of the final report can be downloaded from: https://www.theamazonwewant.org/amazon-assessment-report-2021/
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