Atlantic Haddock (Melanogrammus aeglefinus) Larvae Have a Magnetic Compass that Guides Their Orientation

• Published in: iScience Vol. 19; pp. 1173 - 1178
• Main Authors: Cresci, Alessandro, Paris, Claire B., Foretich, Matthew A., Durif, Caroline M., Shema, Steven D., O’Brien, CJ E., Vikebø, Frode B., Skiftesvik, Anne Berit, Browman, Howard I.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 27-09-2019; Elsevier
• Subjects: Geomagnetism; Ichthyology; Piscine Behavior; Piscine Behavior; Geomagnetism; Ichthyology
• ISSN: 2589-0042; 2589-0042
• DOI: 10.1016/j.isci.2019.09.001

Atlantic haddock (Melanogrammus aeglefinus) is a commercially important species of gadoid fish. In the North Sea, their main spawning areas are located close to the northern continental slope. Eggs and larvae drift with the current across the North Sea. However, fish larvae of many taxa can orient at sea using multiple external cues, including the Earth's magnetic field. In this work, we investigated whether haddock larvae passively drift or orient using the Earth's magnetic field. We observed the behavior of 59 and 102 haddock larvae swimming in a behavioral chamber deployed in the Norwegian North Sea and in a magnetic laboratory, respectively. In both in situ and laboratory settings, where the magnetic field direction was modified, haddock larvae significantly oriented toward the northwest. We conclude that haddock larvae orientation at sea is guided by a magnetic compass mechanism. These results have implications for retention and dispersal of pelagic haddock larvae.
[Display omitted]
•Atlantic haddock larvae drift with the current and spread across the North Sea•In this area, larvae swimming in situ orient to the northwest•In a magnetic laboratory, larvae orient to the same direction, the magnetic northwest•Haddock larvae have a magnetic compass that they use to orient at sea
Piscine Behavior; Geomagnetism; Ichthyology