Robbin Thorp of the University of California, Davis, has been tracking the critically imperiled Franklin's bumble bee (Bombus franklini) since 1998. Surveys for Franklin's bumble bee clearly show declining population. Sightings decreased from 94 in 1998 to 20 in 1999 to 9 in 2000 to one in 2001. Sightings increased slightly to 20 in 2002, but dropped to three in 2003. Thorp saw none in 2004 and 2005; one in 2006; and none since. "I am still hopeful that Franklin's bumble bee is still out there somewhere," said Thorp, emeritus professor of entomology. "Over the last 13 years I have watched the populations of this bumble bee decline precipitously. My hope is this species can recover before it is too late."
Named in 1921 for Henry J. Franklin, who monographed the bumble bees of North and South America in 1912-13, Franklin's bumble bee frequents California poppies, lupines, vetch, wild roses, blackberries, clover, sweet peas, horsemint and mountain penny royal during its flight season, from mid-May through September. It collects pollen primarily from lupines and poppies and gathers nectar mainly from mints.
Sarina Jepson, endangered species program director at the Xerces Society said: "Bumble bees play a critical role in ecosystems as pollinators of wildflowers, as well as many crops". According to a Xerces Society press release, bumble bees are declining throughout the world. Researchers in Britain and the Netherlands have "noticed a decline in the abundance of certain plants where multiple bee species have also declined. For many crops, such as greenhouse tomatoes, blueberries and cranberries, bumble bees are better pollinators than honey bees, and some species are produced commercially for their use in pollination. "
Source:
Western Farm Press, September 15, 2011
http://westernfarmpress.com/management/franklin-s-bumble-bee-edge-extin…
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