The Brief Period of Spring Migration, Short Marine Residence, and High Return Rate of a Northern Svalbard Population of Arctic Char

Abstract

Arctic char Salvelinus alpinus, in the high-Arctic archipelago of Svalbard, entered the Dieset River (79Њ10ЈN) immediately after ice breakup in late June (1991)(1992)(1993), and within 48 h almost half the migrating population had left the lakes where they spent the winter. The majority of the anadromous char descended into the sea within 3 weeks of the melt. The temporal pattern of emigration was independent of body size. The average residence time at sea of the char was 33.6 d, and the maximum was 56 d. The duration of the seawater sojourn was independent of body size. However, the combined time of downstream migration and marine residence was inversely related to body length in early migrating char. Fish that migrated to the sea early tended to stay there longer. The overall return rate ranged from 33.3% for the smallest (15.1-20 cm) to 75.0% for the largest (45.1-50 cm) char, averaging 51.5%. The average return rate for fish shorter than 25.1 cm (first-time migrants) was 42.5%. The upstream run started in mid-July, peaked in August, and was completed by the beginning of September. In contrast to the seaward migration, there was a structured size-precedence in the upstream run, with the large char entering the river first, followed by char of intermediate size and then the smallest anadromous char. The results indicate insignificant immigration to this high-Arctic watercourse. The marked local adaptation to the extreme physical conditions restricted these char to a narrow migrational window. Because this is the first comprehensive study on migratory behavior in anadromous Svalbard char, the results are a valuable contribution to fishery science and management of individual populations in the most northern Eurasian area.

Atlantic salmonSalmo salarL., brown troutSalmo truttaL. and Arctic charrSalvelinus alpinus(L.): a review of aspects of their life histories

“…Populations with larger sea charr are however, found (Rikardsen et al 1997). Populations in the European Arctic have large fish (Svenning 1993;Gulseth & Nilssen 2000;Svenning & Gullestad 2002). According to Johnson (1980), the largest anadromous charr on record (15.9 kg) was caught near Novaja Zemlya.…”

Potential impacts of global climate change on freshwater fisheries

“…These fishes include coldwater stenotherms such as salmonids and riverine sculpins (family Cottidae). Some freshwater fishes are confined to the Arctic and live at high latitudes: the Alaska blackfish (Dallia pectoralis) does occur up to 718N, and the arctic charr can be found as far north as 798N in Eurasia (Gulseth and Nilssen 2000). Otherwise, almost all obligate polar fishes are marine species like the Antarctic plunderfish (Harpagifer antarcticus) and the Arctic cod (Arctogadus glacialis).…”

“…Otherwise, almost all obligate polar fishes are marine species like the Antarctic plunderfish (Harpagifer antarcticus) and the Arctic cod (Arctogadus glacialis). Despite the physiological (Reist et al 2006) and behavioral (Gulseth and Nilssen 2000;Jørgensen and Arnesen 2002) adaptations that provide resistance to freezing, these fish are limited by lack of available habitat. Because fresh water freezes at 08C, these fishes are limited on the upper latitudinal boundaries of their ranges by winterkill and a short growing season.…”

Residency and movement patterns of Arctic charr Salvelinus alpinus relative to major estuaries

“…Anadromous Arctic charr Salvelinus alpinus (L. 1758) undertake a short, seasonally determined, summer sea residency of 1–4 months (Sprules, ; Dempson & Kristofferson, ; Bégout Anras et al , ; Gulseth et al , ; Klemetsen et al , ; Morris & Green, ). Migration to the sea occurs in early spring as soon as rivers are ice‐free (Moore, ; Gulseth & Nilssen, ; Klemetsen et al , ) and individuals remain in warm, estuarine waters up to 10 days during a marine transition phase (Bégout Anras et al , ). Marine migrations significantly increase or restore S .…”