10.5061/DRYAD.6K294
Hawley, Kate L.
Norwegian University of Life Sciences
Rosten, Carolyn M.
Norwegian Institute for Nature Research
Haugen, Thrond O.
Norwegian University of Life Sciences
Christensen, Guttorm
Fram Centre
Lucas, Martyn C.
Durham University
Data from: Freezer on, lights off! Environmental effects on activity
rhythms of fish in the Arctic
Dryad
dataset
2017
behavioural ecology
Arctic charr
biotelemetry
Salvelinus alpinus
2017-11-13T15:01:12Z
2017-11-13T15:01:12Z
en
https://doi.org/10.1098/rsbl.2017.0575
7546672 bytes
1
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Polar regions are characterized by acute seasonal changes in the
environment, with organisms inhabiting these regions lacking diel
photoperiodic information for parts of the year. We present, to our
knowledge, the first high-resolution analysis of diel and seasonal
activity of free-living fishes in polar waters (74°N), subject to extreme
variation in photoperiod, temperature and food availability. Using
biotelemetry, we tracked two sympatric ecomorphs of lake-dwelling Arctic
charr (Salvelinus alpinus n = 23) over an annual cycle. Charr activity
rhythms reflected the above-surface photoperiod (including under ice),
with diel rhythms of activity observed. During the dark winter solstice
period, charr activity became arrhythmic and much reduced, even though
estimated light levels were within those at which charr can feed. When
twilight resumed, charr activity ensued as diel vertical migration, which
continued throughout spring and with increasing day length, despite stable
water temperatures. Diel activity rhythms ceased during the polar day,
with a sharp increase in arrhythmic fish activity occurring at ice-break.
Despite contrasting resource use, circannual rhythms were mirrored in the
two ecomorphs, although individual variability in activity rhythms was
evident. Our data support conclusions of functionally adaptive periods of
arrhythmicity in polar animals, suggesting maintenance of a circannual
oscillator for scheduling seasonal behavioural and developmental
processes.
Photoperiod_DyradTracking data of 23 individual Arctic charr, from Lake
Ellasjøen, Bear Island, Norway. Data is derived by biotelemetry from Sep
2009- Aug 2010.
Bjørnøya
Norway
Lake Ellasjøen