Gulf of Maine, Explained: Salmon Scales

Gulf of Maine, Explained | Oct 11, 2023

GMRI Quantitative Research Associate Miguel Barajas, a member of our Integrated Systems Ecology Lab, led by Dr. Kathy Mills, explains how he uses the scales of Atlantic salmon to answer specific questions about salmon life history in the Gulf of Maine to inform conservation efforts.

In this edition of Gulf of Maine, Explained, Gulf of Maine Research Institute (GMRI) Quantitative Research Associate Miguel Barajas discusses how he studies changes in salmon scales to understand the endangered species' life cycle. Atlantic salmon play a vital role in connecting river and ocean ecosystems, and studying them informs broader conservation efforts aimed at maintaining a healthier global ecosystem.

Salmon scales have mineralized ridges on them known as circuli, and like the rings of a tree, these rings tell a story about individual salmon growth. Wider gaps indicate periods of faster growth and narrower gaps represent slower growth. This growth data can then be connected to marine survival rates, changing environmental conditions, and migratory pathways, and Miguel's job is to try and piece that story together. He researches how long salmon spend at sea and how much they grow compared to their counterparts, and links those differences to other important variables like temperature changes and changes in food availability to identify barriers and obstacles facing the population.

Miguel emphasizes the current challenges facing Atlantic salmon populations, which are continually decreasing despite conservation efforts. That's why identifying and addressing obstacles and barriers to their survival in the ocean is crucial. His research contributes to informed management and conservation efforts aimed at protecting this keystone species.

A Closer Look at our Atlantic Salmon Research

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Gulf of Maine, Explained

In our video series, The Gulf of Maine, Explained, you’ll learn more about important-but-unfamiliar concepts related to our work. We’ll cover commercial fishing, fisheries research, sustainable seafood, education, and more. While we probably won’t answer all your questions in one short video, we hope to spark your curiosity about complicated issues that are central to our mission.

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