Hilltopping Insects

[Kondla, Norbert FOR:EX]

Interesting topic. Hilltops are indeed known to be superior microsites for
butterflies in a variety of ecosystems and I have repeatedly observed this
myself; most recently in a grassland habitat where despite similarity of
nectar sources and larval food plants, Hesperia were consistently found
abundantly on hilltops but rarely seen lower on the slopes.  I am aware of
some older literature on this topic but if anyone has a digital bibliography
on this topic or can email citations from the past 10-15 years plse keep me
in mind. Thx.

-----Original Message-----
From: David Wagner [mailto:dwagner at uconnvm.uconn.edu]
Sent: Tuesday, December 21, 1999 6:55 AM
To: leps-l at lists.yale.edu
Subject: Hilltopping Insects


I am preparing a report for the Massachusetts Chapter of The Nature 
Conservancy on the significance of a summit in southwestern Massachusetts 
that is the highest point in the entire region.  I figured it made sense to 
include a paragraph about the importance of hilltops as mating stations for 
insects, especially for those that might otherwise rarely encounter one 
another.  I reproduce my account below.  There is an ample literature for 
butterflies (?but not moths), but would love to have citations for other 
orders.  Can anyone help with references for non-pompilid Hymenoptera?  Are 
there some benchmark papers on the subject?

Draft Text:  "The Importance of Hilltops

By virtue of the fact that Mount Everett is the tallest peak, as well as 
the most defined summit in the region, it may have special significance as 
a mating station for many insects. The highest point on the horizon--being 
the most reliable topographic features in virtually any habitat--is used by 
many insects as a rendezvous site for courtship and mating (Shields 1967, 
Scott 1968, 1974, Thornhill and Alcock 1983, Britton 1995).  Scott noted 
(1968) that many rare butterflies, which otherwise might have difficulty 
locating one another, use summits of hills and mountains to initiate mating 
behaviors.  Invertebrates known to hilltop include butterflies (especially 
papilionids, pierids, nymphalids, lycaenids, and hesperiids), Hymenoptera 
(e.g., pompilids), and flies (e.g., cuterebridae, gastrophilids, oestrids 
and sarcophagids)(Scott, 1968, 1974, Thornhill and Alcock 1983, Tarrier 
1996, and Povolny and Znojil 1998).

Because adults use vision to locate the highest point on the horizon, it 
makes sense that hilltopping behaviors would be poorly represented (if 
present at all) in the moths--the subjects of this study.  Future surveys 
should emphasize diurnal collections.  And because the most interesting 
organisms are apt to be rare, flight interception or malaise traps should 
be deployed at or very close to the summit."

Any help would be appreciated.


*************************
David L. Wagner
Ecology & Evolutionary Biology
v. 860-486-2139; f. 860-486-6364
dwagner at uconnvm.uconn.edu