medflies in Tampa

[John V. Calhoun]

Mark Walker wrote:

> All of this in addition to added pollutants and the replacement of endemic
> plants with "artificial" roadside flora.
> 
> I wonder how much of an impact this has had on butterfly populations over
> the last 3 


One species that has definately benefited from "artificial" roadside 
plantings is the wild indigo dusky wing, Erynnis baptisiae, a skipper of 
eastern North America.  Originally, this species primarily utilized 
various species of wild indigos (Baptisia--hence the common and 
scientific names), as well as Lupine (Lupinus).  It was not historically 
considered a common species. However, during the 1970's, European 
crownvetch, Coronilla varia, began to be widely planted along 
northeastern roadsides to prevent erosion.  E. baptisiae quickly adapted 
to its abundant presence and now uses this plant as a primary hostplant 
in many portions of its range.  In fact, E. baptisiae has become one of 
the most widespread and common skippers in Ohio over the last two 
decades. Arthur Shapiro published an excellent account of the spread of 
E. baptisiae in Pennsylvania as a result of crownvetch planting (1979, 
J. Lepidopterists' Society, 33:258).           

A second example is the spread of the silvery blue, Glaucophyche 
lygdamus couperi, as a result of the widespread planting of exotic 
tufted vetch, Vicia cracca, along weedy roadbanks in New York (see Dirig 
and Cryan, 1991, J. Lepid. Soc, 45:272-290.

Finally, the rapid southward spread of the meadow fritillary, Boloria 
bellona, has been attributed to adults using highway rights-of-way as 
dispersal corridors.

Although the destruction of native habitats is largely detrimental, some 
species have used it to their advantage and continue to expand their 
ranges as a result.

Best,
John