Tech4Nature Brazil: Turning the Tide for Marajó Mangroves

Located at the mouth of the Amazon River in northern Brazil, Marajó Island is the world’s largest river island. Covering about 40,000 square kilometers, this rich landscape is a dynamic mosaic of biodiversity, where the land, rivers, and sea constantly reshape each other.

The island is also home to the Soure Marine Extractive Reserve (RESEX Soure), the first protected area in Brazil on the IUCN Green List. Established in 2001 after strong advocacy from local fishing and crab-harvesting communities, RESEX Soure safeguards 300 km² of mangrove forests, estuarine waters, and tidal flats.

A mangrove crab / Image credit: ICMBio

The reserve is co-managed by local fishing communities and Brazil’s biodiversity and protected areas agency (ICMBio). Its purpose is to protect the mangrove ecosystem while ensuring that traditional livelihoods, especially artisanal fishing and crab harvesting, remain sustainable.

Today, though, the balance of the ecosystem is under threat.

Climate change is altering coastal dynamics and threatening mangrove ecosystems, while overfishing and illegal fishing — often carried out by outsiders using unsustainable methods — put additional pressure on crab populations and the livelihoods of over 1,600 families.

Technology meets tradition

The inclusion of the Soure RESEX as a flagship Huawei-IUCN Tech4Nature project reflects not only its ecological importance, but also the strength of its community-based governance. By combining digital tools with traditional knowledge and launched in 2024, the project aims to enhance protection of this unique ecosystem by measuring how climate change is impacting the mangrove ecosystem.

Tech4Nature comes in with a very important impact, helping us achieve what both the conservation unit management and the community wanted: to really understand what was happening.Lucas Gadelha,
Environmental Analyst – ICMBio

Tech4Nature Brazil partner Federal University of Pará (UFPA) developed an innovative, low-cost environmental sensor system tailored to the extreme conditions of mangrove ecosystems. Commercial equipment available in the global market is prohibitively expensive and ill-suited for large-scale deployment in areas as vast as the Soure RESEX, which spans nearly 300 km².

Monitoring climate change in mangroves presents unique difficulties:

• Logistical barriers: Dense mangrove roots and intertidal mudflats are extremely unstable and accessible only during short low-tide windows.
• Environmental stress: The humid, salty air is highly corrosive to electronic devices and rapidly degrades conventional equipment.
• Large-scale coverage: The vast size of the RESEX Soure makes it economically unfeasible to rely on costly imported monitoring devices for long-term use when factoring in maintenance and replacement.

Smart about monitoring

The UFPA-designed devices integrate environmental sensors capable of measuring key variables, including water salinity, temperature, and level; air temperature and atmospheric pressure; wind intensity and direction; and rainfall.

The sensors, which are designed to withstand the humid, corrosive, and muddy conditions, automatically collect data and transmit it through cellular network chips, creating a near real-time stream of environmental information.

Compared with similar commercial solutions, the prototype tested pre-deployment proved to be up to 70% more cost-effective, while retaining high precision and accuracy.

Image credit: LAPMAR/UFPA / Solar-powered sensor array

Our goal was to lower the acquisition and maintenance costs of this equipment so we could support communities, extractive reserves (RESEX), and local authorities in monitoring and managing the conservation units.Daniel da Silva,
Oceanographer & Researcher – UFPA (Federal University of Pará)

Data is continuous rather than seasonal, enabling scientists and policymakers to track long-term environmental changes in the mangrove ecosystem, anticipate the impacts of climate change, and guide public policy.

Sustainable crab harvesting

Alongside analyzing how climate change affects the mangrove ecosystem over the long-term, monitoring mangrove crab populations delivers insights into the factors, including climate conditions and fishing practices, that affect their population numbers over time. Mangrove crabs are a keystone resource that are ecologically pivotal to the well-being of mangrove ecosystems.

Overharvesting undersized, juvenile crabs that have not yet reproduced can cause populations to decline, affect ecosystem balance by reducing nutrient cycling and sediment turnover, and – over the long-term – affect local livelihoods by reducing available stocks.

Working closely with the local fishing community and measuring the size of harvested crabs are key methods for establishing the sustainability of current fishing practices.

The mangrove, to me, is practically everything. It’s where I make a living for my family. For as long as I can remember, I've seen our community sustain itself through crab fishing.Antônio Dias,
Fisherman & Crab Gatherer

More than 3,200 interviews with local fishers over 2025 and 2026, the first census of its type carried out in Soure, has provided important insights into the sustainability of fishing practices. Moreover, ecological monitoring conducted in accordance with national protocols across nine sampling areas in the mangrove ecosystem lays the foundations for more robust annual monitoring.

A partnership approach

As well as International Union for Conservation of Nature (IUCN) and Huawei, and with the support of federal and state governments, the Tech4Nature partnership brings together Chico Mendes Institute for Biodiversity Conservation (ICMBio), RARE Brazil, the Federal University of Para (UFPA), and local associations ASSUREMAS and ACCS.

Image credit: RARE / The team in the field

Image credit: ICMBio / The team in the field

Image credit: RARE Brazil/ Feedback workshop with communities

Tech4Nature is a pioneering global initiative that combines IUCN's scientific knowledge and frameworks with the expertise and technology of companies like Huawei.Beatriz Aydos,
Program Officer – IUCN

Technology isn't just about chips, antennas, or providing fast internet; our big turning point, especially with the global TECH4ALL initiative, was putting digital innovation to work for people and the planet.Evandro Zampieri,
Public Relations Director – Huawei Brasil

The Tech4Nature Brazil project strives to deliver tangible local impact by strengthening community voice, securing livelihoods, and safeguarding resources, thus ensuring the mangrove ecosystem continues to sustain future generations.