An extensive network of ancient fish traps, dating back 4,000 years, was discovered in the wetlands of Belize's Crooked Tree Wildlife Sanctuary. The findings, published Friday in the journal Science Advances, reveal that the semi-nomadic people who constructed this system may have laid the groundwork for the rise of the Maya civilization.
Using drones and Google Earth data, archaeologists mapped a network of earthen canals. "The aerial imagery was crucial to identify this really distinctive pattern of zigzag linear canals running for several miles through wetlands," Eleanor Harrison-Buck, co-author of the study, stated, as reported by The Guardian.
The canal networks were built as early as 4,000 years ago by semi-nomadic people in the Yucatán coastal plain, surprising researchers who initially assumed these constructions were made by the ancient Maya. "The early dates of the channels surprised us at first because we all assumed these huge constructions had been made by the ancient Maya living in the nearby urban centers," Eleanor Harrison-Buck explained.
Radiocarbon dating of material buried in the bottom of one channel suggests that the network has been around for at least 4,000 years. These ancient canals, paired with holding ponds, were used to channel and catch freshwater species such as catfish, aiding in sustaining and diversifying the diets of the local population. The network was designed to channel floodwaters into ponds to trap fish, helping to build a foundation for later cultural heights and supporting a growing population.
"The network of canals was designed to channel annual flood waters into source ponds for fish trapping and would have yielded enough fish to feed as many as 15,000 people year-round, conservatively," stated Harrison-Buck, professor of anthropology and director of the Belize River East Archaeology (BREA) project.
"It seems likely that the canals allowed for annual fish harvests and social gatherings, which would have encouraged people to return to this area year after year and congregate for longer periods of time," said Marieka Brouwer Burg, professor of anthropology at the University of Vermont and BREA co-director.
The radiocarbon dates indicate that such landscape-scale wetland enhancements may have been an adaptive response to long-term climate disturbance recorded in Mesoamerica between 2200 and 1900 BCE.
"Such intensive investments in the landscape may have led ultimately to the development of the complex society characteristic of the pre-Columbian Maya civilization, which subsequently occurred in this area by around 1200 BCE," Brouwer Burg noted.
"It's really interesting to see such large-scale modifications of the landscape so early—it shows people were already building things," Claire Ebert, a University of Pittsburgh archaeologist who was not involved in the study, said, according to The Guardian.
At the height of the Maya civilization, people in this region built temples, roads, pyramids, and other monuments. The Maya civilization developed complex systems of writing, mathematics, and astronomy. The new findings suggest that the early intensification of aquatic food production offered a high-value subsistence strategy that was instrumental in the emergence of sedentism and the development of complexity among pre-Columbian civilizations like the Maya.
The research team conducted digs in Belize's Crooked Tree Wildlife Sanctuary, a sprawling marshy grassland dotted with lakes and cut by streams. With the support of the local community, the team plans to return to Crooked Tree to investigate a larger sample of these landscape-scale modifications identified across a broad area of northern Belize.
"Wetlands have always been a critical ecosystem for humans across the globe," said Samantha Krause, professor of geography and environmental studies at Texas State University, according to Science Daily. "Knowing how to manage wetland resources responsibly is essential for the continued resilience of these ecosystems both in the past and today," she added. "The Archaic hunter-gatherer-fishers knew how to protect their resources and use them in a way that could sustain these habitats, not exhaust them, which explains their long-lasting occupation in this area," Krause further stated.
The Guardian, Ars Technica, Science Daily, and 20 Minutos were among the websites that reported on the discovery.
This article was written in collaboration with generative AI company Alchemiq