Volume 28 Number 1
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Wisconsin Entomological Society Newsletter UPDATE ON THE REGAL FRITILLARY IN WISCONSIN by Ann Swengel Fritillary (Speyerta idalia) Thomson/Barneveld (Iowa), and Hwashe listedspectacularin WisconsinRegalas (Green),Waterfowl PineProductionIsland* Area(s)*(Columbia),(St. threatened in 1989 and endangered Croix). Only the three starred areas in 1997. My husband, Scott have records known from before the Swengel, and I have surveyed Regal 1990s, and the three largest known populations here each year since populations today do not have 1990. We also conducted a com- records from before the 1990s. It's panion study in five other states all but impossible to piece together & p (Illinois, Iowa, Minnesota, Missouri, the very long-term picture of the Regal Fritillary (Speyerta idalia) and North Dakota) from 1990 Regal's distribution and trend in Prioto: Ann swengel. 6/17/97 through 1999. In the latter three Wisconsin. If even half the effort in states, many large Regal populations the 1990s to find and publish Regal populations in these places. We occurred, allowing us to learn more records had occurred in earlier started surveys at Pine Island in quickly (or at all) many interesting decades, how many more 1993 but found no Regals until relationships to habitat character- populations would have been found 1995, when we recorded populations i s t i c s a n d then? We'll never at two sites. management that know. But we can In 1997, Scott was determined to would be very III use what we know search for Regals at Buena Vista. It d i f f i c u 1t t o ; now to help improve has the factors most strongly associ- demonstrate only the future outlook ated with higher Regal numbers in w i t h t h e f ew for this species in our multi-state study (very large populations in our state. grassland size, presence of wetter Wisconsin. W e s t a r t e d and drier grassland types, and F r o m o u r surveys at Muralt unintensive management by light surveys, others' re- and Oliver in 1990, grazing and/or haying, with any ports (published in as well as at the first burning in small, scattered, and this newsletter), tract acquired at the infrequent fires). My ornithologist informal tips, and Thomson preserve husband also noticed that sites with the DNR's statewide ("site 1"), where we larger Regal populations also had status survey in discovered the first better bird-watching, and Buena 1993 and 1994, the Regal for this area. Vista has an outstanding avian Regal Fritillary was Regal Fritillary (closed position) U n f o r t u n a t e 1y , community. Still, I thought he was known to exist Photo: Ann swengel, 6/18/92 a n o th e r i n i t i al crazy to expect Regals there, because during the 1990s as research finding was Regals are prairie butterflies. I a population (multiple individuals the disappearance of the population should have trusted my own seen in the site on multiple dates) at at Spring Green. In 1992, we started analysesl Poetically, I found the first only six sites or clusters of sites: surveys at Hogback and the later Regal-a feeling I will treasure for the Buena Vista (Portage County), land acquisition at Thomson ("site rest of my life. Apparently, Regals Hogback (Crawford), Muralt/Oliver* 2"), after others discovered Regal Please see, Regals, Page 2 The Wisconsin Entomological Society Newsletter is published three times a year, at irregular intervals. It is provided to encourage and facilitate the exchange of information by the membership, and to keep the members informed of the activities of the organization. Members are strongly encouraged to contribute items for inclusion in the newsletter. Please send all news items, notes, new or interesting insect records, season summaries, and research requests to the editor: Janice Stiefel, 2125 Grove Road, Bailey's Harbor, WI 54202, e-mail: [email protected] NOTE: Please report any address changes to Les Ferge, 7119 Hubbard Ave., Middleton, WI 53562. e-mail: [email protected] Wisconsin Entomological Society Newsletter - March 2001 e 2 2001 Dues Notice! numbers) because we had other MTES Spring Meet,ing things to do (like work) and too Milwaukee Public Museum collection envelope is many sites to check, at least in Educatfort Classroom, nclosed with this news- minimally acceptable weather. So Grourtd Floor letter, for the convenience of we aimed to survey each site in the members who haven't paid their main flight period, not specifically Sat. April 22, 2002, 2:00 P.at. dues for 2001, No envelope is pro- peak, since it's hard to know exactly Please check in at the vided if you are paid up for 2001 or when peak is until after it's passed· information desk on the main beyond. Please check the address But we've mostly come fairly close concourse. Anyone who wishes to label on this newsletter for your to peak anyway. For 90% of the visit the collections or borrow current dues status. Send check to populations in the figure (i.e., each material should contact the our treasurer, Tom Rocheleau, site in each year), a survey occurred appropriate curator in advance: 3100 Buena Vista St., Madison, WI within seven days before or after the Lepidoptera-Carla Penz: email 53704. Also appearing after your date on which we observed the most [email protected], 414-278-6936; name will be your membership Regals anywhere in the state (i.e., Other Insects-Gary Noonan: category (Individual, Family, our observed peak date). In the email carabid@mpm. edu, 414- Sustaining, or Patron). Be sure to other 10%, surveys occurred within 278-2758; Non-insect Inverte- notify us of any address changes 11 days before to 15 days after the brates-Joan Jass: email when you send in your check or peak date. Since about 3 weeks (or [email protected], 414-278-2761. you may notify Les Ferge (address more) typically pass between first The meeting will include an over- given at the bottom of page 1). W Regal adult and peak week, and then view and tour of the Puelicher afterusuallythataboutto last4-5adult,(or Numbersmore) weeksare Butterfl Garden, as well as Regals, from Page I high for a fairly broad period of 1-2 f r nd noomiona oenrs to Pahse define prairie somewhat differently weeks before and after peak week. Pellitteri· email pellitte@ than humans do. Meanwhile, Jim The most obvious thing about entomology.wisc.edu, 608-262- Margenau and his students re-dis- the graph is how tangled and erratic 6510. W covered Regals in St. Croix County the lines are. Some of this is due to at large but certainly not pristine the vagaries of when we got our grasslands. The figure shows the highest count relative to weather and per year during our study period, highest survey counts of Regals at flight period timing at a given site. except for no fires in 1990, 1993, each site still supporting a Regal But a lot of this looks like the 1998, and 2000. Our highest survey population that we've monitored for abundancefluctuationsdiscussedso totals occurred in 1990 and 1993, at least four years. We used the much by the British, from their wide- with very low numbers from 1997 to same survey route each year (except spread long-term butterfly surveying. 1999, but an encouraging (if small) we expanded the route at Pine Island The bar graph imbedded amongst increase in 2000. I didn't graph when we found Regals there). All the lines for individual sites shows Oliver, where Bob Borth reported a surveys occurred with no rain, and the average number of Regals re- consistent population in this news- either a minimum temperature of corded at the four sites surveyed letter in 1992, because we found 1-4 68°F or a minimum of 20% sun- each year from 1992 to 2000. individuals on five dates in 1991, shine with a minimum temperature Unfortunately, considerable 1993, and 1994, and none since of 60°F. We surveyed sites several population decline occurred at (1995-2000). This tiny prairie near times each flight period, but couldn't Muralt, where the entire habitat has Muralt was entirely burned in 1989, do weekly surveys at each site (which been rotationally burned since the 1992, 1997, and 2000. I also left would ensure hitting near peak 1970s, with about 10-40% burned out Pine Island (site 2), where we 140 - recorded a population in 1995 and 1996 but no Regals in summer 120 1997-2000, following fires that Mean orfour sites burned this entire habitat in spring 100 - (1992-2000) 1997 and again in 1998. A popu- Hogback lation still occurs, but is small and so - -o- suena 1 precarious, at Pine Island (site 1), which has recently been entirely so Thomson 2 burned over with partial fires in -o-- Murait 1995, 1997, and 1999. Over the 40 - Thomson 1 yearS, we have communicated with the owning agencies and managers of 20 -e-- Pine 1 these sites, and remain hopeful for wider implementation of the excel- o - : a : - - : a . · l lent Regal management information Please see.Regals, Page 5 Wisconsin Entornological Society Newsletter - March 2001 Page 3 2000 PHOTO SALON WINNERS Pandorus Sphinx Moth Larva (Eumorpha pandorus) FIRST PLACE Janice Stiefel, Bailey's Harbor, WI-Photographed 8/31/00 Found on Wild Grape by Scott Randall in Glenbeulah, WI White-Marked Tussock Larvae (Orgyia leucostigma) T HIRD PLACE Janice Stiefel. Bailey's Harbor. WI Photographed: 8/9/00; 36 days old Columbia Silkmoth (Hyalophora columbia) Unidentified Cupmoth Larva SECOND PLACE FOURTH PLACE Gene Drecktrah, Oshkosh, WI Janice Stiefel, Photographed: 6/6/00 Door Co.