Скачать или смотреть How can we know the health of the St. Lawrence River? | Ask a Scientist

Fish are excellent indicators for monitoring water health. Watch biologist Yves Paradis explain how researchers closely monitor the river’s fish to assess its health. Get ready to see how scientists dive into the water to tackle this important question!

This video was produced alongside the release of the 2024 Overview of the State of the St. Lawrence.

https://planstlaurent.qc.ca/en/

** Transcript **

Kalina: The St. Lawrence River is much more than just a body of water. It supports daily life, the economy, and local culture. It provides drinking water for millions of people, and is home to a wide variety of plants, animals and ecosystems. So, we need to take good care of it. We received a question about this from José from St-Joseph-De-Lepage, Quebec.

José: Hello, my name is Josée Martin and I've been living near the St. Lawrence River for about 12 years. I love walking along the banks of the St. Lawrence, because it's so beautiful, so calm and the view is marvelous. By the way, I was wondering how scientists keep track of the health of the St. Lawrence River?

Kalina: Yves Paradis, a biologist for the province of Quebec, answers this question by explaining how researchers closely monitor the fish in the river to assess its health. Get ready to dive deep into how scientists take the plunge to tackle this important issue!

Yves Paradis: Fish are excellent indicators for monitoring the health of the St. Lawrence River, but we’re not interested in just one species of fish; we’re interested in several species known as the fish community.

To sample them in the different sections of the St. Lawrence River, we’ll be using different monitoring networks that will be adapted to the inhabitants of the river section and also to the inhabitants of the estuary. And we’re going to monitor different types of information on these species: their abundance, species composition, size structures, age structures, and also any external anomalies we might find on the fish. This information will help us determine the state of the St. Lawrence River and understand its evolution over time.

In recent years, we have observed various changes in the fish communities of the St. Lawrence River. Some species have declined, such as the yellow perch in the Lake Saint-Pierre sector, while others have improved, for example, the lake sturgeon, which was considered overfished in the 1980s and is now much more abundant. Another interesting case is the striped bass, a species that had vanished completely from the St. Lawrence River in the 1960s, and which experienced… which has been reintroduced and is now swimming successfully in the St. Lawrence River.

So, in short, when the fish in the St. Lawrence are doing well, the whole state of the St. Lawrence is doing well also.

Kalina: Thanks to ongoing research, we’re gaining a better understanding of the St. Lawrence River’s health and can take steps to protect this vital ecosystem. Every discovery brings us closer to the goal of managing the river sustainably for the well-being of future generations. Keep sending us your questions, and maybe yours will be featured in a future episode of Ask a Scientist!