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<dd>Williams, P., S. Colla, and Z. Xie. 2009. Bumblebee vulnerability:
Common correlates of winners and losers across three continents.
Conservation Biology <b>23</b>:931-940.<br><br>
</dl>Abstract: It is widely agreed that in many parts of the world
some bumblebee (Bombus) species have declined, and that this has often
been driven by land-use changes that cause reductions in the abundance of
food plants. There is much less agreement about how changes in food
plants affect some bumblebee species more than others. We sought to
identify which species' characteristics are generally associated with the
relative winners and losers by comparing the 3 independent bumblebee
faunas from parts of Britain, Canada, and China. Using available survey
data, we assessed species characteristics, including competition with
congeners, climatic specialization, proximity to climatic range edge,
food specialization, phenology, body size, and range size. Results of our
meta-analysis of correlations showed support for the hypotheses that
decline susceptibility is generally greater for species that have greater
climatic specialization, for species in areas where they occur closest to
the edges of their climatic ranges, and for species that have queens that
become active later in the year. The latter characteristic may render a
species at a particular disadvantage when they have long colony cycles if
there are losses of food plants in mid to late colony development.<br>
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