Geomagnetic variations and fish year-class strength (113848)

Fish often return to their birthplace to spawn, a behavior known as homing, but how they navigate across vast, featureless oceans remains unclear. One theory is that fish, like birds, use the Earth’s geomagnetic field to guide their migrations. Since this field changes over time, it may influence migration success and, in turn, fish population dynamics. This project explores whether geomagnetic variation can help explain fluctuations in fish year-class strength. Using examples from salmon, eels, and sharks, the research investigates how marine species detect and use magnetic cues - such as intensity, inclination, and declination - to navigate. While the exact sensory mechanisms remain partly unknown, experimental and modeling studies support the idea that geomagnetic navigation plays a key role in marine life.

Funding
The project is funded by Villum Foundation.

Research area: Ecosystem based Marine Management
Research area: Marine Living Resources