The Dwindling Herring: Fishing, Warming Seas, and Predators at Fault

Atlantic herring has been a big deal in Canada's seafood industry since the 1960s, with the Scotian Shelf-Bay of Fundy herring fisheries being a major player. However, this stock has been struggling since the mid-1960s, despite efforts to boost it since 2003. Researchers wanted to understand why management actions aren't working, so they analyzed data about the herring population, the environment, and human activities. They discovered that the amount of fish caught, where they're caught, and when new fish join the population matter a lot. Warmer seas and predators attacking herring eggs also play a role. This information is crucial for managing the herring stock and considering how climate change might affect it. For decades, Atlantic herring has been the top catch in Canada's seafood industry. The Scotian Shelf-Bay of Fundy herring fisheries are a significant part of this, accounting for up to 75% of the total herring catch some years. Sadly, their numbers have been declining since the mid-1960s. Management actions to improve the situation started in 2003, but the fish population remains low. Understanding what's causing this decline is key to effective management. Researchers looked at 52 data series about the herring population, the environment, and human activities over time. They used a method called structural equation models to figure out what factors most influence the herring population. They found that the rate at which fish are caught and where they're caught, along with the timing of new fish joining the population, are crucial. Surprisingly, warmer seas and predators attacking herring eggs also have a big impact. These findings are important for managing the herring population. They show that considering how climate change affects the early stages of herring life and looking at the ecosystem as a whole are essential for effective management.