Microprobe analyses of anadromous Arctic charr, Salvelinus alpinus, otoliths to infer life history migration events

• Published in: Polar biology 1998, Vol.19 (1), p.1-8
• Main Authors: RADTKE, R. L, DEMPSON, J. B, RUZICKA, J
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Freshwater; Fundamental and applied biological sciences. Psychology; Marine; Salvelinus alpinus; Thermoregulation. Hibernation. Estivation. Ecophysiology and environmental effects; Vertebrates: anatomy and physiology, studies on body, several organs or systems
• ISSN: 0722-4060; 1432-2056

Otoliths of Arctic charr, Salvelinus alpinus, from north Labrador were examined to gather life history information pertinent to anadromous migrations. Wavelength dispersive electron microprobe measurements confirm the presence of strontium in otolith tissue. Trace element analyses of charr otoliths imply that otolith strontium/calcium concentration ratios are related to external environmental factors with salinity having a great influence. Otoliths clearly record habitat shifts consistent with migration across major salinity boundaries. Most charr first migrate to sea following at least 2 years in freshwater. Generally, when anadromy begins, it continues annually. Robust relationships in otolith chemistry, combined with macrostructure patterns in field-captured specimens, provide time-series data describing individual migrational histories. Validation studies are still required in order to couple information contained within daily increments with chemical analyses to infer additional temporal events in diadromous migrations.