Data from: Microsatellite analysis of museum specimens reveals historical differences in genetic diversity between declining and more stable Bombus species

Worldwide most pollinators, e.g. bumblebees, are undergoing global
declines. Loss of genetic diversity can play an essential role in these
observed declines. In this paper, we investigated the level of genetic
diversity of seven declining Bombus species and four more stable species
with the use of microsatellite loci. Hereto we genotyped a unique
collection of museum specimens. Specimens were collected between 1918 and
1926, in 6 provinces of the Netherlands which allowed us to make
interspecific comparisons of genetic diversity. For the stable species B.
pascuorum, we also selected populations from two additional time periods:
1949–1955 and 1975–1990. The genetic diversity and population structure in
B. pascuorum remained constant over the three time periods. However,
populations of declining bumblebee species showed a significantly lower
genetic diversity than co-occurring stable species before their major
declines. This historical difference indicates that the repeatedly
observed reduced genetic diversity in recent populations of declining
bumblebee species is not caused solely by the decline itself. The
historically low genetic diversity in the declined species may be due to
the fact that these species were already rare, making them more vulnerable
to the major drivers of bumblebee decline.