Distribution, movements, and mortality of anadromous arctic char, Salvelinus alpinus L., in the Cumberland Sound area of Baffin Island

Abstract

During 1972 the downstream movement of anadromous artic char, Salvelitius alpinus L., from two rivers flowing into Cumberland Sound, Baffin Island, began during the middle of May and was completed within 2 weeks. This movement took place during both the day and night. Upon reaching saltwater, many char older than 9 years (longer than 20 cm) began to migrate along the shore of the Sound at a rate of 0.6-0.9 km/day with the result that the average maximum distance travelled from the natal river was 40-50 km. Char 6-9 years old, 10-20 cm in length, remained much closer to the rivers while those younger than 5 years never entered saltwater. During the period of saltwater residence, the fish frequently moved into the intertidal zone and freshwater. Maturing fish of both sexes were occasionally found in saltwater. The upstream migration to the lakes began during the second week of August and was completed within 5-6 weeks. Females tended to ascend the rivers before males, although fish of all different size and age migrated upstream simultaneously. Migration occurred during both the day and night. The maximum distance anadromous char moved from saltwater was 40 km. The char were found only in freshwater between May and September and were normally located near the bottom of lakes at a depth of 15-40 m.During this period, large scale movements were probably very limited. Average annual mortality was estimated at 16.0 % per year with the highest rates (25-30 %) occurring at ages 10 and 15-17 years. Many fish probably died of old age but physical deterioration during and after spawning was also an important cause of death.

Geographic influences on fine-scale, hierarchical population structure in northern Canadian populations of anadromous Arctic Char (Salvelinus alpinus)

“…Importantly, this result implies that dispersal occurs more frequently along shorelines and not necessarily by the most direct route. This, again, is in line with previous tagging and telemetry work that suggest that most movement occurs near coastal habitats in Arctic char (Moore 1975;Spares et al 2012). Few studies have assessed geographic variables on Arctic population of salmonids and, to our knowledge, none have assessed this in anadromous populations of Arctic char.…”

“…In nearby Frobisher Bay acoustic tagging revealed that Arctic char spend the majority of time in the top three meters of the water column (Spares et al 2012). Thus, when sea ice is present, this could act as a barrier to dispersal and previous studies from Cumberland Sound suggest most Arctic char movement is close to the shore in ice-free areas (Moore 1975).…”

“…For example, if dispersal is restricted by sea ice for a proportion of the time subsequent to Arctic char entering Cumberland Sound, the north-south barrier is not surprising. Indeed, the ice-free season in Cumberland Sound can be relatively short, persisting for a large proportion of the time while Arctic char are in marine habitats (Moore 1975). In nearby Frobisher Bay acoustic tagging revealed that Arctic char spend the majority of time in the top three meters of the water column (Spares et al 2012).…”

Preference for nearshore and estuarine habitats in anadromous Arctic char (Salvelinus alpinus) from the Canadian high Arctic (Victoria Island, Nunavut) revealed by acoustic telemetry

“…For instance, Berg and Jonsson (1989) found that veteran migrants returned earlier than first-time migrants, but all tagged fish in the present study were probably veteran migrants. Previous studies also suggested that female Arctic char returned to fresh water before males (Moore 1975;Berg and Berg 1993), but this pattern was not observed in the present study. Females preceding males during the upstream migration is not necessarily a widespread phenomenon in other salmonids.…”

Les sites de fraye de l'omble chevalier (Salvelinus alpinus L.) dans le Léman

“…Apparemment, seuls les ombles du Lac Lone frayent sur la vase, parce qu'il n'y a probablement plus de plage de gravier favorable dans le lac (JONSSON et OSTLI, 1979). MOORE (1975) constate que les ombles de Cumberland Sound, sur l'île de Baffin, frayent également sur le sable. Il attribue ce fait à la densité trop importante des reproducteurs sur les lieux de fraye, certains ne trouvant plus de place sur les omblières véritables.…”