Evidence for Non-Anadromous Behaviour of Arctic Charr (<i>Salvelinus alpinus</i>) from Lake Hazen, Ellesmere Island, Northwest Territories, Canada, Based on Scanning Proton Microprobe Analysis of Otolith Strontium Distribution
Keywords:anadromy, arctic charr, Salvelinus alpinus, Ellesmere Island National Park Reserve, life history, otolith microchemistry, scanning proton microprobe, trace elements
Scanning proton microprobe analysis was used to determine the distribution of strontium (Sr) in otoliths from arctic charr (Salvelinus alpinus) of known non-anadromous, known anadromous, and unknown life histories. Strontium concentration patterns in otoliths of known non-anadromous charr were low and relatively flat (with little variation) from the core area to the outermost edge of the otolith, while patterns for known anadromous charr were characterized by a similar low, flat region for the first several years of life, followed by marked oscillatory increases and decreases in Sr content for the duration of the fish's life. Small and large forms of Lake Hazen charr of unknown life histories exhibited Sr profiles that were similar to those of the known non-anadromous charr, which strongly suggest that Lake Hazen charr are non-anadromous. These results indicate that Lake Hazen is a "closed" system with energy cycling primarily within the system; this conclusion suggests that a conservative approach would be appropriate for the management of the Lake Hazen charr population.