Occurrence data of small rodent species from the Yamal peninsula (1958–2022)

Range shifts and changes in dominance of species in communities are among
the major predicted impacts of climate change on ecosystems, supported by
numerous modeling studies. While climate is changing particularly rapidly
in the Arctic, little observational data is available to document
predicted changes in the composition of communities, in particular from
the large Russian tundra areas. Small rodents are a key component of
tundra ecosystems implementing important ecological functions both as
herbivores and as main prey for a whole guild of predators. Here we
document changes over 60 years in occurrence of nine species of small
rodents along a latitudinal gradient spanning from the forest-tundra
ecotone to the high Arctic tundra on the Yamal Peninsula. All data were
obtained using a single method: snap-trapping. In general, the occurrence
of lemmings, specialized arctic endemics, decreased in the southern parts
of the peninsula, whereas the occurrence of voles, representing boreal or
wide-spread species, increased and expanded northwards. The occurrence of
Siberian lemmings (Lemmus sibiricus) in particular declined over the whole
latitudinal gradient and possibly disappeared from the southernmost zones,
whereas collared lemmings (Dicrostonyx torquatus) declined significantly
only in the forest tundra. The strongest increase was observed in the
tundra zones for narrow-headed voles (Lasiopodomys gregalis), a
wide-spread species inhabiting meadows and riparian habitats, and
Middendorff’s voles (Alexandromys middendorffii), a primarily low Arctic
species inhabiting waterlogged tundra. Both species also expanded their
distribution range northwards during the last two decades. The observed
changes might be due to the effect of several drivers of environmental
change occurring in concert: climate warming both in winter and in summer,
and increased human activity notably related to intensive reindeer herding
and industrial development.