Pairing Etuaptmumk with Acoustic Telemetry to Uncover the Seasonal Distribution of Ji'kaw in Pitu’pa’q

In the waters of eastern Canada, a fish known as the striped bass, or Ji'kaw in the Mi'kmaw language, plays a vital role in both the ecosystem and the culture of coastal communities. These fish are not just a food source; they are a thread connecting the ocean to the rivers and the people who have lived along these shores for thousands of years. However, the life of a striped bass is complex. They are anadromous, meaning they are born in fresh water, grow in the ocean, and return to fresh water to spawn. In the Bras d'Or Lake, a large, intricate estuary on Cape Breton Island, scientists and local Indigenous knowledge holders have long wondered how these fish move. Do they stay put in the winter? Do they travel to the open ocean to breed? Or do they wander between the lake's many hidden bays? Answering these questions requires more than just counting fish; it requires understanding the rhythm of their lives across the changing seasons.

To solve this puzzle, a team of researchers from the Unama'ki Institute of Natural Resources, Dalhousie University, and the Ocean Tracking Network joined forces with Mi'kmaw communities. They used a method called acoustic telemetry, which involves attaching a small, harmless sound-emitting tag to a fish. These tags send out a unique signal that can be picked up by underwater receivers placed around the lake, much like a cell phone tower picking up a signal from a phone. By listening to these signals, the team could track exactly where each fish went, day and night, for nearly a year. This project was guided by a philosophy called Etuaptmumk, or "Two-Eyed Seeing," which weaves together Indigenous ways of knowing with Western science. The goal was not just to collect data, but to create knowledge that would help the local communities manage and protect their fishery.

The researchers tagged 45 striped bass between May and October 2024. They chose to use a technique called electro-immobilization to hold the fish still during surgery, rather than chemical anesthesia. This decision was made because chemical anesthetics can linger in the fish's flesh, which would be disrespectful if the fish were later caught and eaten as part of the traditional food system. The team also took time for ceremony and ecological observation before and after the tagging, honoring the relationship between the people and the water. Over the next year, the underwater receivers recorded more than 193,000 detections of the tagged fish, painting a detailed picture of their movements.

The data revealed that the striped bass do not stay in one place; their lives are divided into four distinct seasons of movement. In the spring, as the water warms, the fish emerge from their winter hiding spots and begin to travel across the lake. This period, which aligns with the Mi'kmaw moon for "Birds Laying Eggs Time," is a time of high activity. Many fish move in a directed way toward the Great Bras d'Or Channel, a narrow waterway that connects the lake to the Atlantic Ocean. The researchers found that 24 of the tagged fish, or about 58 percent, actually left the lake during this time. Once they exited, some of these fish were detected in the Miramichi River, a famous spawning ground hundreds of kilometers away. This confirmed that a significant portion of the striped bass in the lake are part of a larger population that travels to the ocean to reproduce.

During the summer, the fish's behavior changes. They spread out more diffusely across the lake's basins, a phase the researchers called "exploring." This period coincides with the time when trees are fully leafed out. The fish seemed to concentrate in the East Bay area, near the community of Eskasoni. This suggests they are likely feeding and building up energy reserves for the coming winter. The data showed that the fish were less likely to move between the different basins of the lake during these months, preferring to stay in specific feeding grounds.

As autumn arrived and the water began to cool, the fish entered a "returning" phase. They started moving again, this time gathering in the northern parts of the lake, particularly in Nyanza Bay. This movement aligns with the Mi'kmaw moon for "Mate Calling Time," a season when animals gather. The fish seemed to be heading toward specific areas to prepare for the winter. Finally, in the winter, the fish settled into a quiet "overwintering" period. They stopped moving between the basins and stayed in deep, sheltered areas, likely to conserve energy in the cold water.

One of the most important findings was the high level of connection between the different parts of the lake. The fish moved freely between the various bays and channels, proving that the entire lake is a single, connected system. This is crucial for management because it means that what happens in one part of the lake affects the fish in all other parts. The study also showed that the fish leave the lake through only one specific exit, the Great Bras d'Or Channel, even though there are other ways out. This concentration of movement creates a specific bottleneck where the fish are most vulnerable to fishing pressure or other threats.

The research also challenged a common local belief. Many people thought that the smaller, younger striped bass, often called "schoolies," stayed in the lake until they grew much larger. However, the tracking data showed that more than half of these smaller fish actually left the lake to go to the ocean. This means that the lake is not just a nursery for young fish; it is a critical feeding ground and overwintering site for fish of all sizes, including those that will eventually travel far away to spawn.

By combining the precision of acoustic tracking with the deep, historical knowledge of the Mi'kmaw people, this study has provided a clear map of the striped bass's life in the Bras d'Or Lake. The results show that these fish are highly mobile, moving between the lake and the ocean, and that their movements are deeply tied to the seasons. This knowledge is now being used to help Mi'kmaw communities and government agencies develop better ways to manage the fishery. Instead of applying blanket rules to the whole lake, managers can now consider the specific needs of the fish in different areas at different times of the year. This approach, rooted in both science and tradition, ensures that the striped bass population remains healthy and that the cultural and food rights of the Mi'kmaw people are protected for generations to come.