No net insect abundance and diversity declines across US Long Term Ecological Research sites

Recent reports of dramatic declines in insect abundance suggest grave
consequences for global ecosystems and human society. Most evidence comes
from Europe, however, leaving uncertainty about insect population trends
worldwide. We used > 5,300 time series for insects and other
arthropods, collected over 4-36 years at monitoring sites representing 68
different natural and managed areas, to search for evidence of declines
across the United States. Some taxa and sites showed decreases in
abundance and diversity while others increased or were unchanged, yielding
net abundance and biodiversity trends generally indistinguishable from
zero. This lack of overall increase or decline was consistent across
arthropod feeding groups, and was similar for heavily disturbed versus
relatively natural sites. The apparent robustness of U.S. arthropod
populations is reassuring. Yet, this result does not diminish the need for
continued monitoring and could mask subtler changes in species composition
that nonetheless endanger insect-provided ecosystem services.