Sam, T'ai et al.,
Note the following passage pertaining to Osmia cornifrons from Giles and
Ascher, 2006:218, J. Hym. Res. 15(2), where this species is considered as
potentially invasive for the first time:
"After wide distribution and release, this species has recently
established large populations in natural and urban (e.g., Manhattan and
Brooklyn, NYC) habitats in the eastern United States to the point where it
could be considered invasive..."
Regarding Anthophora plumipes, it should be noted that this well-known
polylectic species is native to at least 25 countries ranging from Spain
to Japan and Greece. Some areas where A. plumipes occurs have notoriously
cold winters, including Korea (don't forget the "Frozen Chosen" Marines at
the Chosin Reservoir), Finland, and Siberia, so there is reason to
question Batra's 2003 (citation below) assertion that "any escaping bees
would not survive in the cold climate" of Maine and also her conclusion
that the bee would be of particular use in the southeastern United States.
It is interesting to note that similarly dubious claims have been made
about the climatic limitations and preferences of Bombus impatiens, which
supposedly requires cold winters but is in fact well known to occur in
subtropical Miami in south Florida.
The very wide range of A. plumipes in the Palearctic can be seen on this
global map plotting literature records by country together with Sam
Droege's specimen records from the USA:
I strongly recommend that anyone interested in Osmia cornifrons and
Anthophora plumipes read or reread "Bee Introductions to Pollinate our
Crops" (pp. 85-98 of "For nonnative crops, whence pollinators of the
future?" edited by Karen Strickler and James H. Cane) by Suzanne W. T.
Batra, the principal proponent of spreading exotic Palearctic bee species
to the North America. Therein, she asserts that "Widespread alarm about
the introduction and spread of exotic organisms, including bees, is a
fairly recent phenomenon gaining strength in the 1990s. It seems to be a
religious view (sensu Radhakrishnan, 1951)..." In common with certain
members of the Bush administration, she considers immigrants such as
Palearctic bees as a legitimate means of increasing biodiversity in the
United States. In this chapter, she repeatedly dismisses concerns
expressed by other biologists about release of exotic bees by the USDA as,
e.g., merely "Emotion (moral outrage)" and as "overreaction to slight
risk...an example of misplaced conservatism common to regulatory
agencies." In her view the burden of proof was entirely on those opposing
the introductions. The divergence between her views on exotic species and
those held by most biologists interested in maintaining native diversity
could not be more stark.
When considering the spread of Osmia cornifrons and Anthophora plumipes it
is very important to remember that these did not accidently arrive in the
USA like Megachile rotundata but instead were deliberately released with
governmental approval, largely as the result of the strongly held views of
a single person. In my opinion, insufficient attention was given to
scientific considerations at the time, but it seems likely that these
species are now a permanent part of our fauna, in which case we will have
plenty of opportunity for future assessment of their merits.
> Sam et al.:
> I concur with the skyrocketing nature of Osmia cornifrons/taurus. I pulled
> 7 O. taurus off the porch screen here at my field station in the northern
> Shenandoah Valley in one day this year. I didn't see this species at all
> here 5 years ago when I arrived. I'm attaching a photo of a nest site I
> discovered this spring that indicates it isn't all that picky about
> cavities. The bee is returning to its nest site in a pile of greenhouse
> roof material. The chambers are rectangular and open ended and there were
> probably about 30-50 females nesting there.
> I haven't seen Anthophora plumipes yet.
> At 09:46 AM 5/17/2007 -0400, you wrote:
>>I am having some trepidations about 3 species of recently introduced bees
>>whose populations appear to be skyrocketing.
>>The epicenters for these 3 species appear to be the D.C area with O.
>>cornifrons, O. taurus having spread widely throughout VA, WV at least and
>>A. plumipes still appearing largely circumscribed to the D.C. area.
>>All 3 are now abundant enough that I get numerous emails and calls about
>>their presence and I find them abundant, at times, in our trapping.
>>Here are some conservation issues.
>>The Osmia species both seem to have very similar habits to the native O.
>>lignaria, size is similar and come from the same subgenus. There are now
>>so common as I can't believe there isn't some competition going on, for
>>hole sites, pollen, etc. Additionally, a recently discovered parasite of
>>these species has been found in the region and may also adversely affect
>>native Osmians. Orchardists now spread O. cornifrons and perhaps the
>>alike O. taurus around, but wild populations appear to far outnumber
>>managed trap nests.
>>This group is very easy to study as all 3 readily take to trap
>>nests. Thus it would be easy to look at survivorship, fecundity,
>>parasitism rates over large regions, where they are established, becoming
>>established, and where they have yet to arrive.
>>A. plumipes is a different bird and may or may not compete with native
>>species, but it is becoming very common in the D.C. are and it would be
>>very interesting to run parallel studies of the movement, fecundity, etc.
>>of this spring species compared to that of the Osmians.
>>I won't have time to pursue this, but wanted to get the idea out in the
>>ether. Given that 7 or so species of exotic bees have been discovered
>>this decade already, compared to an average of 1 per decade previously, I
>>am afraid introduced species are going to become more of an issue in the
>>Sam Droege Sam_Droege@...
>>w 301-497-5840 h 301-390-7759 fax 301-497-5624
>>USGS Patuxent Wildlife Research Center
>>BARC-EAST, BLDG 308, RM 124 10300 Balt. Ave., Beltsville, MD 20705
>>I met a traveller from an antique land
>>Who said: Two vast and trunkless legs of stone
>>Stand in the desert ... Near them, on the sand,a
>>Half sunk, a shattered visage lies, whose frown,
>>And wrinkled lip, and sneer of cold command,
>>Tell that its sculptor well those passions read
>>Which yet survive, stamped on these lifeless things,
>>The hand that mocked them, and the heart that fed:
>>And on the pedestal these words appear:
>>"My name is Ozymandias, king of kings:
>>Look on my works ye mighty and despair!"
>>Nothing beside remains. Round the decay
>>Of that colossal wreck, boundless and bare
>>The lone and level sands stretch far away.
>> -- Percy Bysshe Shelley
> T'ai Roulston
> Research Asst. Prof., Dept. Env. Sciences
> University of Virginia
> Associate Director
> Blandy Experimental Farm www.virginia.edu/blandy
> 400 Blandy Farm Lane
> Boyce, Va. 22620 USA
> Ph# (540) 837-1758 ext 276 Fax (540) 837-1523
John S. Ascher, Ph.D.
Bee Database Project Manager
Division of Invertebrate Zoology
American Museum of Natural History
Central Park West @ 79th St.
New York, NY 10024-5192
work phone: 212-496-3447
mobile phone: 917-407-0378