Helping the Amazon's Caboclos riverine communities cope with extreme weather events

Riverine communities are known to be adaptable to hydro-climatic changes. However, they are experiencing higher and longer tides and floods. A research project is developing an early warning system and tools to help these communities in the Delta of the Amazon River adapt to extreme events.

Tides expand the Amazon's delta's lacework of rivers and streams twice a day, inundating a tiny part of the largest rainforest in the world. Known as lançantes, this daily cycle makes the forest a spectacular nursery for crustaceans, mostly shrimp, and many species of fish that are the main source of food and income for the caboclos, as the people living in the riverine communities are called.

Some 5 million people live in the Amazon floodplains, mostly in the estuary region where an estimated 200,000 to 300,000 families are settled.

Over the last 30 years, however, the caboclos have been noticing that the tides run higher than in the past and that spring floods last longer, causing more environmental damage and threatening their communities. The dry spells in late fall are also growing drier. Despite the lack of long-term hydro-climatic data for the region, it's difficult to deny that the climate is changing in the Amazon's delta.

How the cabolos adapt

The caboclos have tried to adapt to these changes by dedicating more time to collecting products from the forest. Among other items, they harvest oil for cosmetics from the pracaxi tree; seeds, leaves, fruit, and wood (pau mulato and pracuúba, for example); palm fronds for thatch; and fruits such as açaí, banana, guava, and cupuaçu. The higher and longer tides and floods have almost stopped them from cultivating crops such as cassava, corn, tomatos, beans, and squash.

“We see this as a source of flexibility, which results in an enhanced ability to adapt to change,” says Miguel Pinedo-Vasquez, a researcher from the International Research Institute for Climate and Society (IRI), part of the Earth Institute at Columbia University, New York.

He is a member of a team of scientists working on a three-year project, started in 2012, on “Sociocultural Adaptations of Caboclos in the Amazon Estuary of Brazil to Extreme Tidal Events”, funded by IDRC.

"Our study is looking not only at land use, but at the change in fish species to those that are more flood tolerant," says Nathan Vogt, a researcher at the National Institute for Space Research (INPE), based in São José dos Campos, Brazil, and part of the Proestuario project team.

According to Oriana Almeida, Professor at the Nucleus of High Studies of the Amazon at the Federal University of Pará (NAEA/UFPA) and head of the Caboclos´project, although they experience daily floods that restrict their economic activities, the caboclos have been trying to diversify their production beyond açaí, which is the main source of family income. They fish in the estuary waters using a matapi, a handcrafted trap made of local plants, and collect buriti to make craft items from its fibers.

Their incomes have increased dramatically in the last 10 years as a result of a number of government cash-transfer schemes, such as Bolsa Família (family grant), seguro-defeso (an insurance paid to artisanal fishermen during the spawning season), and pensions. “In the past, the economic activities accounted for 90% of the riverine families´ income. Nowadays, the public cash-transfers represent 45% of their income”, says Almeida.

The lack of long-term data

The results of extreme tidal events and other hydro-climatic disturbances are evident in the Amazon estuary. However, the lack of long-term data makes forecasting difficult. For the moment, data about the tides' height in the Amazon's estuary dates back to 2007 only.

“This is not sufficient data for a long-run study”, says Kátia Fernandes, from IRI at Columbia University. She explains that only longer historical data will clearly show what is happening with the Amazon estuary tides. Even the connection between extreme tidal events and climate change is not well understood.

Based on her research, she believes that extreme events are more likely to be related to an increase in the amount of rain over the Amazonas basin than to sea level rise, a widely-accepted hypothesis.

The project's researchers have recently begun to collect data. In Belém, Brazil's navy collects data using a tide gauge set up by the project. There are also three rulers installed in three communities, which daily measure sea level.

Besides higher and longer tides and floods, the region is experiencing other disturbances, such as erosion and the expansion of small streams into secondary channels. Villages are changing location more quickly than in the past as the land is eroded or constanly silted. Winds are becoming stronger, creating seasonal windstorms that impede the flowering and fruiting of trees, includingthe  açaí and other fruit trees planted and managed by caboclos.

The need for planning tools

“Since the project is about sociocultural answers to such disturbances, we are documenting the process of land use changes from agriculture to agro-forest and forest management systems. Such processes seems to be one of the most important adaptive responses to hydro-climatic extreme events,” says Pinedo-Vasquez. Nevertheless, he adds, the timing and intensity of such extreme events are unusual and limit the ability of these people to adapt.

Needed are tools to help vulnerable populations prepare and cope extreme events, such as an early warning system. The development of such tools is one of the project's goals. The research is also generating evidence to help decision-makers plan and develop adaptation strategies for the district's municipalities.

José Alberto Gonçalves Pereira is a Brazil-based writer.

This article profiles a project supported by IDRC’s Climate Change and Water program,Socio-Cultural Adaptations of Caboclos in the Amazon Estuary of Brazil to Extreme Tidal Events.

Watch an interview with researcher Oriana Almeida: