Summer Movements of Radio-tagged Arctic Charr (<i>Salvelinus alpinus</i>) in Lake Hazen, Nunavut, Canada

Abstract

ABSTRACT. Radiotelemetry was used to determine whether Lake Hazen arctic charr (Salvelinus alpinus) were anadromous and to determine movements of the charr within the lake. In 1995 and 1996, 62 and 55 charr, respectively, were captured, radio-tagged, and released back into the lake. A fixed data acquisition system recorded limited movements of radio-tagged charr in the upper reaches of the Ruggles River, the only outlet from the lake to the sea, in 1995. When movements of radio-tagged charr within Lake Hazen were monitored opportunistically in 1995, most of the relocated charr were found in warmer, more productive waters associated with inflowing streams. No movements of radio-tagged charr in the Ruggles River were recorded in 1996 when the data acquisition system was operated in the lower reaches of the river. These observations supported the conclusions of a study of Lake Hazen charr otolith strontium distribution that Lake Hazen charr were non-anadromous. The Ruggles River may be a detriment to anadromous behaviour because of its length (ca. 29 km), velocity (up to 2.25 m·s -1 ), and the year-round presence of aufeis (layered ice buildup). In summer, instead of migrating to the sea to feed, Lake Hazen charr appear to move to feed on abundant prey found in areas where inlet streams enter the lake.Key words: anadromy, arctic charr, Ellesmere Island, life history, migrations, Quttinirpaaq National Park, radio-tagging, Salvelinus alpinus RÉSUMÉ. On a fait appel à la télémesure pour savoir si l'omble chevalier (Salvelinus alpinus) du lac de Hazen est anadrome et pour connaître ses déplacements dans le lac. On a capturé 62 ombles en 1995 et 55 en 1996 qu'on a munis de radio-émetteurs avant de les relâcher dans le lac. En 1995, un système fixe de collecte de données a enregistré les déplacements restreints des ombles munis de radio-émetteurs dans le cours supérieur de la rivière Ruggles, la seule décharge du lac dans la mer. Quand on a pu vérifier les déplacements de ces ombles dans le lac de Hazen en 1995, la plupart des poissons se trouvaient dans les eaux plus chaudes et plus productives associées à des ruisseaux d'arrivée. En 1996, après qu'un système de collecte de données a été installé dans le cours inférieur de la rivière Ruggles, on n'y a enregistré aucun déplacement des ombles munis de radio-émetteurs. Ces observations viennent étayer une étude sur la distribution du strontium otolithique chez l'omble du lac de Hazen, qui concluait que ce poisson n'était pas anadrome. Il se peut que la rivière Ruggles soit peu propice à un comportement anadrome en raison de sa longueur (env. 29 km), de sa vitesse (jusqu'à 2,25 m•s -1 ) et de la présence toute l'année d'un dôme de glace (Aufeishugel). En été, au lieu de migrer vers la mer pour se nourrir, l'omble du lac de Hazen semble se déplacer vers les zones où les ruisseaux se déversent dans le lac et qui contiennent des proies en abondance.Mots clés: anadrome, omble chevalier, île d'Ellesmere, évolution biologique, migrations, parc national Quttinirpaaq, pose de radio...

Mercury concentrations in landlocked Arctic char (Salvelinus alpinus) from the Canadian Arctic. Part II: Influence of lake biotic and abiotic characteristics on geographic trends in 27 populations

“…1, Table 1). With the exception of Ruggles River (Lake Hazen, Ellesmere Island), all outflows of the study lakes do not allow for migration, and Lake Hazen char are confirmed to be lake resident [35]. Selection of sites was constrained by accessibility and guided by past sampling campaigns, and/or current monitoring programs.…”

Using stable isotopes to confirm the trophic ecology of Arctic charr morphotypes from Lake Hazen, Nunavut, Canada

“…Detailed morphological and meristic studies by Reist et al (1995) demonstrated the forms differed substantially in body form, colour, number of pyloric caecae, caudal peduncle length, and pelvic and pectoral fin lengths, but could not establish whether differences arose for trophic or migratory reasons. More recently, analyses of the distribution of strontium in otoliths (Babaluk et al, 1997) and radio-tagging (Babaluk et al, 2001) demonstrated that both forms are non-anadromous. Results suggest that differences in growth trajectories during the adult phase arise from differences in feeding strategies and habitat use.…”

Rapid decline in river icings detected in Arctic Alaska: Implications for a changing hydrologic cycle and river ecosystems

“…In the presence of river icing, sediment typically aggrades upstream of the icing and leads to braided channels [Harden et al, 1973;Bennett et al, 1998] (e.g., Figure 2a). These sediment deposits and channel morphologies provide a multitude of unique and important ecosystem benefits, including organismal habitat and refugia for key species such as Chinook salmon [Babaluk et al, 2001;Bradford et al, 2001]. Alterations of river flows and deposits associated with icings affect economically important civil infrastructure and recreation opportunities through, for example, roadway and rafting hazards [Morse and Wolfe, 2015].…”