Arthropod communities in the Second College Grant, NH

Arthropods are active during the winter in temperate regions. Many
use the seasonal snowpack as a buffer against harsh ambient
conditions and remain active in a refugium known as the subnivium.
While the use of the subnivium by insects and other arthropods is
well-established, far less is known about winter community
composition, abundance, biomass, and diversity and how these
characteristics compare with the community in the summer.
Understanding subnivean communities is especially important given
observed and anticipated changes in snowpack depth and duration with
changing climate. We studied winter and summer insects and other
arthropods using pitfall trapping in northern New Hampshire, where
snowpack is still relatively intact. We found that compositions of
the subnivium and summer arthropod communities differed. The
subnivium arthropod community featured moderate levels of richness
and other measures of diversity that tended to be lower than in the
summer community. More striking, the subnivium community was much
lower in overall abundance and biomass than the summer community.
Interestingly, some groups and species of arthropods were dominant
in the subnivium but either rare or absent in summer collections.
These putative “subnivium specialists” included one spider (order:
Araneae), Cicurina brevis (Emerton,
1890), and three rove beetles (order:
Coleoptera, family: Staphylinidae)
Arpedium cribratum Fauvel, 1878,
Lesteva pallipes LeConte, 1863, and
Porrhodites inflatus (Hatch, 1957). This study
provides a detailed account of the subnivium arthropod community,
presents novel concepts, and establishes baseline information on
arthropod communities in the North American northeastern temperate
forest.