First Michigan Specimens of Libellula Vibrans Fabricius (Odonata: Libellulidae)

Content Provider	Semantic Scholar
Author	Craves, Julie A.
Copyright Year	2006
Abstract	Libellula vibrans Fabricius (Odonata: Libellulidae) is a large dragonfly previously known in Michigan only from sight or literature records. In 2005, two small populations were found in Wayne County, Michigan. _ Libellula vibrans Fabricius (Odonata: Libellulidae), the Great Blue Skimmer, is not mentioned in historical lists of Michigan Odonata (Byers 1927, Kormondy 1958, O'Brien 1997). Prior to 2005, there are no specimens in the University of Michigan Museum of Zoology's (UMMZ) insect collection, where voucher specimens from the Michigan Odonata Survey (MOS) are housed. A published report of L. vibrans for Michigan was by Nishida (1999) finding one individual on 22 June 1995 at a small wooded wetland in Westland, northwestern Wayne Co., Michigan. His paper also includes a photograph of a male from this location dated 10 July 1995. If he obtained a specimen, its whereabouts are unknown. A report of a sight record from Wayne County from 1999 (Hudson et al. 1999), as well as two sight reports from Washtenaw County from early July 2005 (M. F. O'Brien, pers. comm.) prompted me to search for this species, focusing on the Westland area. On 9 July 2005, Darrin O'Brien and I observed a single male in a small wooded swamp in the Holliday Nature Preserve in Westland, Wayne County, Michigan. As Westland is a highly developed suburb of Detroit, I believe this is the same spot in which Nishida (1999) made his observations; in fact, I checked this spot periodically in 2003 searching for L. vibrans. The site itself is a wooded wetland of less than one hectare. About 20% of the site is open water, and the rest liberally interspersed with buttonbush (Cephalanthus occidentalis) and many fallen trees. Water is shallow, probably not more than a half-meter deep in wet years, and is covered by duckweed (Lemna sp.) by mid-summer. Water overlays thick organic muck which also lines the shore. The wetland is situated in an ~40 ha forest fragment that is part of a larger (200-ha), somewhat linear forest preserve in northwestern Wayne County. We were able to clearly observe a male L. vibrans on our initial observation on 9 July but it flew off and could not be relocated. We returned the following day and made a systematic search of the area. After a half-hour, we located three to five male L. vibrans, characteristically hunting from perches in dappled shade and allowing close approach (Dunkle 2000, Abbott 2005). We took two voucher specimens which have been deposited in the Insect Collection at the UMMZ. Coincidentally, this was ten years to the day that Nishida photographed a male in what is presumably the same spot. On 29 August 2005, O'Brien and I were able to access another small (<2 ha) wooded pond on the north end of Willow Metropark, located in southwestern Wayne County, and ~20 km nearly due south of the Westland site. Earlier in the season this pond had been too wet for close approach. By late August, the pond itself had areas of standing water only a few centimeters deep surrounded by soft muck becoming overgrown with wetland plants such as Lobelia cardinalis and Polygonum coccinea. The area is ringed by forest and connected by an intermittent stream to the Huron River, <100 m away. We immediately saw 1 Craves: First Michigan Specimens of Libellula Vibrans Fabricius (O Published by ValpoScholar, 2006 92 THE GREAT LAKES ENTOMOLOGIST Vol. 39, Nos. 1 & 2 several male L. vibrans perched on fallen trees overhanging the pond. When one would fly close to another, they would give chase but not far or vigorously. We took one voucher for this location.
Starting Page	13
Ending Page	13
Page Count	1
File Format	PDF HTM / HTML
Volume Number	39
Alternate Webpage(s)	https://scholar.valpo.edu/cgi/viewcontent.cgi?article=2154&context=tgle
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article