Valle Paleazza

Beyond Venice: Life in the Lagoon

When most travelers picture Venice, they imagine winding canals, stone bridges, and bustling piazzas. But Venice is just one part of a larger ecosystem and a UNESCO World Heritage Site. The historic city sits at the heart of the Venice Lagoon, which spans 212 square miles (550 square kilometers), making it the largest wetland in the Mediterranean Sea. Often called the “floating city,” Venice was built atop 118 of the lagoon’s marshy islands. Its iconic canals, now traveled by gondolas, began as natural tidal channels that were later expanded and engineered over time.

Beyond the city, the lagoon is a patchwork of islands, salt marshes, seagrasses, tidal flats, and fishing valleys. While Venice itself attracts millions of visitors each year, the lagoon and its historic villages offer a slower, rural escape for those looking to avoid the crowds. Travelers can cycle along quiet paths through fishing valleys and salt marshes, explore the lagoon by boat, or go birdwatching in its wetlands, where flamingos, herons, and egrets can be spotted. 

A Fragile Ecosystem Under Pressure

Despite its proximity to one of Europe’s most visited cities, the lagoon remains a haven for wildlife. It is home to nearly 100 fish species and provides nesting grounds for more than half of Italy’s bird species. Visitors can join fishermen on their boats to learn about age-old practices and savor classic seafood dishes, such as sardele in saor and bigoli in salsa, made with fish from the lagoon. 

Over the past century, humans have reshaped the lagoon by diverting rivers, building jetties and artificial embankments, and dredging deep canals to accommodate large ships. Pollution, motorboat traffic, and marine litter have placed additional pressure on the lagoon’s fragile ecosystems. These changes have had profound effects, altering sediment flow, accelerating erosion, and contributing to the widespread loss of salt marshes and aquatic plant beds. As a result, the lagoon’s salt marshes have shrunk to less than a quarter of the size they were in 1810.

Blue Carbon and Climate Resilience

This loss doesn’t just affect biodiversity; it also weakens one of the lagoon’s natural defenses against climate change. Salt marshes, seagrass, and other aquatic vegetation act as blue carbon ecosystems, some of the planet’s most effective carbon sinks. These coastal habitats can sequester carbon up to ten times faster than land-based forests, making them valuable allies in the fight against climate change. Their decline not only reduces the lagoon’s ability to store carbon but also removes natural barriers that help protect against climate-related threats like storm surges and rising sea levels.

This disappearance of these natural buffers, combined with a buildup of sediment from past human activities, has worsened flood risks across the lagoon. The area is naturally prone to high tides, known as acqua alta. Venice is especially vulnerable to this phenomenon due to its location near the lagoon inlet, and many visitors have experienced it firsthand, wading through flooded piazzas or walking on raised platforms as water seeps into shops and cafes. While these high-water events aren’t new, they’re happening more often as the land slowly sinks and sea levels rise due to climate change.

Worsening flood risks and other ecological changes are already taking a toll on local wildlife. Many coastal birds, like terns and plovers, that nest on salt marsh islets are now threatened. The population of common terns has plummeted by about 87% in the Venice Lagoon over just two decades. One of the main causes is the increased flooding of their nesting sites during the breeding season, as the number of flood days nearly doubled, making it harder for chicks to survive.

Fishing Valleys: Nature and Tradition Intertwined

While many human interventions have disrupted the lagoon’s natural balance, the traditional fishing valleys, known locally as valli da pesca, offer a different story. Originally created for fish farming as early as the 11th century, many of these semi-enclosed wetlands have evolved into important habitats. Formed by enclosing shallow areas with earthen embankments and using gates to control the tides, these man-made landscapes mimic natural wetlands through a mosaic of ponds, canals, and reed beds. Algae, aquatic plants, and small invertebrates—like crabs, shrimp, and mollusks—form the base of complex food webs that support birds, fish, and other wildlife. 

Beyond their ecological role, the fishing valleys provide food and income for local communities through small-scale fish production and aquaculture. For many families, working in the valleys is a way of life passed down through generations, rooted in traditional fishing techniques, specialized crafts related to the structures’ maintenance, and deep knowledge of the lagoon’s ecosystems.

But this long-standing connection between people and nature is under threat. Many fishing valleys are unmanaged or abandoned, leading to problems such as polluted water, low oxygen levels, and a loss of habitat and landscape diversity. As a result, they capture significantly less CO2 from the atmosphere and might even release more carbon than they absorb, turning them from a natural solution into part of the climate problem.