FIELD SURVEYS FOR THE DIONECOPPER BUTTERFLY

PREPARED BYNorbert G. Kondla, RPBio

FORColumbia Basin Fish & Wildlife Compensation Program

And

September 2002

COLUMBIA BASINFISH & WILDLIFECOMPENSATION

PROGRAM

www.cbfishwildlife.org

FIELD SURVEYS FOR THE DIONE COPPERBUTTERFLY

Susan Borkin photograph

Prepared by

Norbert G. Kondla P.Biol., RPBio.

and

W. Dean Nicholson

Prepared for

Columbia Basin Trustand

Columbia Basin Fish and Wildlife Compensation Program

12 September 2002

2

INTRODUCTION

Lycaena dione Scudder, 1868 is a butterfly in the family Lycaenidae. It has beenvariously referred to by the common name of Dione Copper, Grey Copper orGreat Grey Copper in popular books. It is widespread on the Great Plains ofNorth America but becomes decidedly local in the cordilleran environments of thewest. It was unknown in BC until Lloyd Janz discovered its presence inConfederation Park (Cranbrook) near Elizabeth Lake in 1989 (Shepard 1990). Noother populations were known up to the spring of 2001 (Guppy and Shepard2001) and consequently the BC population has been viewed as being of seriousconservation concern (Guppy et al. 1994, Guppy and Kondla 2000, Kondla et al.2000, Guppy and Shepard 2001, Pyle 2002). Dean Nicholson discovered anadditional site in July of 2001 at Bar Creek north of Lumberton Road (Kondla etal. 2002).

The Committee on the Status of Endangered Wildlife in Canada subsequentlycommissioned a formal status report in the summer of 2001. The Columbia BasinFish and Wildlife Compensation Program and the Columbia Basin Trustcontributed funding to enhance the amount of time available for field surveys.This brief report deals with the resulting field surveys that we conducted.Illustrations of two of the life cycle stages of Lycaena dione are provided inAppendix 2 and some BC adults are illustrated in Appendix 3.

METHODS

We met for an on-site examination of the habitat available at the ConfederationPark site prior to the 2002 Dione Copper flight period. We noted that largeRumex spp. were abundantly present. This was in stark contrast to the assertionby Shepard in Guppy and Shepard (2001) that this population only hasPolygonum amphibium available as a larval host plant. Kondla subsequentlyreviewed published literature, personal file information and information providedby others to characterize the range of habitats used by the butterfly. The picturethat emerged was that of a butterfly that occupies a variety of wet to dry andeven weedy habitats with presence of the larger Rumex species – the onlyknown host plant for the butterfly larvae.

We reviewed maps to locate candidate roads and areas for subsequent vehicle-based investigation. Butterfly voucher specimens were collected at occupiedsites. Photographs were taken of most occupied sites and brief notes weremade on salient habitat attributes. Binoculars were used to scan wetlands andother habitat patches that were not amenable to intimate foot searches due totime and logistical constraints.

We largely selected lower elevation areas in the Rocky Mountain trench for fieldinvestigation because we knew from past field work over the years that suitable

3

habitats were not present in the higher elevation forested areas. This area wasexamined from the USA border north to Parsons, a linear distance of about 250kilometres. A valley corridor extending from the British Columbia-Alberta borderalong Highway 3 southwest to Moyie was also examined. The Kootenay Rivervalley around Creston was searched fairly intensively over more than one daydue to published occurrence of the butterfly in nearby northern Idaho. The areabetween Cranbrook and Kimberley was searched as well.

Total time spent in search of occupied butterfly sites was over 111 hours spreadbetween 2 July 2002 and 11 August 2002. Kondla spent time on field work on 8different calendar days and Nicholson conducted his searches over 13 differentcalendar days. Additional time was spent prior to the flight period in search ofcandidate places to visit during the flight period. Kondla drove more than 2000km in examining potential sites and areas. Nicholson spent more time in theimmediate Cranbrook area and travelled approximately 900 km.

RESULTS

We located 13 additional sites with L. dione present. These are distributed overa substantial geographic area (approximately 250 sq. km.) roughly centred onCranbrook. The most distant site was Bummers Flats to the northeast ofCranbrook. Three sites were found in Cranbrook; one east of Cranbrook, two inMoyie, one in Marysville, two near Wycliffe, two on Pighin road and one on JimSmith Lake road. Thus the butterfly has now been documented from 15 localsites in British Columbia.

Apparently suitable patches of Rumex without visible Lycaena dione were foundat the following locations:♦ A large stand of Rumex in a gravel pit near the junction of Mission-Wycliffe

Road and Airport Road; also another one about .5 km to the east,♦ Patch of Rumex on west side of highway about .5 km north of Confederation

Park,♦ Patch of Rumex along edge of marsh on east side of Highway 3 about 3 km

north of Jaffray,♦ Patch of Rumex off Ft. Steele-Wardner Road east on Mause Road,♦ Large patch of Rumex on edge of ephemeral wetland beside Davis Road

near Roosville by Tobacco Plains IR,♦ Abundant Rumex in kettle beside road to Suzanne Lake about 3 km east of

Jaffray road,♦ Abundant Rumex on waste area in Invermere near James Chabot Provincial

Park,♦ Abundant Rumex in depression of hayfield off Highway 95 about 3 km north

of Edgewater,♦ Abundant Rumex in and at edge of marsh by Highway 21 near Rykerts border

crossing.

4

Observed butterfly behaviour ran the normal gamut; including nectaring, basking,resting, aerial contest behaviour, patrolling, dispersing. Three males wereobserved engaging in aerial contest behaviour at the Bummers Flats site wherethey used the adjacent CPR railroad as a hilltop. Males appeared to use acombination of perching and patrolling for mate locating behaviour. Femaleswere also noted displaying aggressive behaviour to other L. dione individualswhile they were resting on plants.

One male at Bummers Flats was discovered in rapid, straight line flight along thebase of the railroad track about 500 metres from the breeding site and wasmoving away from same, suggesting it was in dispersal mode. Many kinds ofherbaceous plants were found to serve as resting/perching locations. Oneimmediate post-copulo pair was discovered on peppergrass (Lepidiumdensiflorum). When startled the male rapidly flew away and the female retreatedinto the foliage. Daily flight activity appeared to be normal, with activity beginningin the morning with radiant warming by sunshine and continuing through the dayso long as temperatures were suitable. On one occasion butterflies were foundto be actively nectaring on alfalfa at 1900 hours.

None of the sites where butterflies were seen were wetland habitat. All werefound stationary or in flight in dry to mesic habitat. The lowest elevationoccupied site was Bummers Flats at 790 metres, while the highest elevationoccupied site was Jim Smith Lake road at 1036 metres.

The sites with the greatest number of observed individuals were theConfederation Park site (at least 30 individuals) and the Jim Smith Lake road site(at least 20 individuals). These were rough counts taken over small areas inshort time frames and should not be used to draw any inferences about absolutepopulation size. On one occasion the Bummers Flats site was walked from oneend to the other and then back again. Seven individuals were seen on bothtransects. One week earlier, eleven individuals were seen at the site during abrief visit.

Distances between occupied sites varied from two city blocks to 15 kilometres.Population structure thus evidenced appears to be a classic metapopulationstructure centred on the landscape dynamics of Rumex.

Following are brief descriptions of the known occupied sites. Note that latitudeand longitude coordinates are given in degrees, minutes, seconds format. Asummary map of all documented Lycaena dione sites is presented as Figure 24in Appendix 1.

5

Bummers Flats

More than 100 Rumex plants are situated between the CPR railroad track andHighway 93, south of Wasa. This breeding site occupied an area about 10metres wide and 500 metres long. Vegetation other than the Rumex consisted ofweedy grasses and forbs. Nectar sources were in good supply, includingCirsium, Sonchus, Melilotus and mustards. No dock nor coppers were seen inthe extensive wetlands adjacent to this site. It is noteworthy that another BCbutterfly with a very restricted range was also found at this site: the SilverSpotted Skipper (Epargyreus clarus).

Figure 1. Map showing approximate location of Bummers Flats site. Thecoordinates are 50.43.03, 115.41.30.

6

Figure 2. View of habitat at Bummers Flats site. Note Rumex plants inforeground.

Cranbrook-Confederation Park

This is the first known BC site discovered by Lloyd Janz. The primary breedingarea consists of patches and scattered plants of Rumex on landfill and an old millsite. Some dock plants also grow close to the water of Elizabeth Lake, which inits present regulated state is larger than the natural water body that preceded itand is also a non-natural habitat managed primarily for waterfowl production. D.Nicholson has persistently seen L. dione flying in this dry weedy area for severalyears. Note that the area is no longer a provincial park as shown on the old mapused in Figure 3.

7

Figure 3. Map showing approximate locations of Confederation Park site (latlong49.30.05, 115.47.26) and Jim Smith Lake road site (latlong 49.29.31,115.48.46). The Jim Smith Lake road site is discussed on pages 10 and 11.

Figure 4. View of the main breeding area at Confederation Park.

Cranbrook

Three new sites were found in the City of Cranbrook. One was a small site ofRumex in an industrial site near Joseph Creek. Habitat with Rumex likelyextends further down the creek. Another was a small stand of Rumex in a vacantlot near a shopping center and Joseph Creek. The third was at the city gravel pitand Rumex was abundant there.

8

Figure 5. Map showing approximate locations of the three new sites in Cranbrook(latlongs 49.30.38, 115.46.44; 49.32.00, 115.44.30 and 49.31,115.45.13).

Figure 6. View of the Cranbrook gravel pit site.

9

Figure 7. View of the site in the industrial area at the north end of ‘the strip’ inCranbrook.

Figure 8. View of the vacant lot site near a mall in Cranbrook.

Cranbrook East

One small site was found on a disturbed slope adjacent Highway 3 about 2kilometres east of the Cranbrook/Kimberly interchange (latlong49.33.30,115.42.00).

10

Figure 9. Map showing the approximate location of the Cranbrook East site.

Figure 10. View of the roadside site east of Cranbrook along Highway 3.

Jim Smith Lake Road

A site with a dense population and abundant Rumex was discovered in a yard ina residential area along the road to Jim Smith Lake. At least 20 adults were

11

found avidly nectaring on alfalfa growing at the edge of the road surface of agravel home access road known as Laidlaw Road. See Figure 5, page 8 for amap of the location. Latlong for this site is 49.29.31, 115.48.46.

Figure 11. View of the Jim Smith Lake road site.

Figure 12. Nectar source for the Jim Smith Lake road population, alfalfa growingon Laidlaw road.

12

Marysville

The butterfly was present at a small site (less than 15 plants) next to the arena(latlong 49.38.20,115.57.00).

Figure 13. Map showing the approximate location of the occupied site inMarysville.

Figure 14. View of the Marysville site.

13

Moyie

Two small occupied sites were found within two blocks of each other in thetownsite; along a street and on private property (latlong 49.17.15, 115.49.00).

Figure 15. Map showing the approximate locations of the two sites in Moyie.

Figure 16. A typical stand of Rumex in the village of Moyie.

14

Palmer Bar Creek

A potentially expansive site where the butterfly was fairly common in 2001 butonly one individual was seen in three visits during 2002. It is interesting to notethat the water level was substantially higher in 2002 as compared to 2001. Apatch of Rumex in an old stream backwater where the butterflies were seen in2001 was flooded in 2002 and unusable as a breeding site. Rumex plants arescattered in grassy areas along the periphery of shrubby areas near the stream.

Figure 17. Map showing approximate location of Palmer Bar Creek site. Latlongis 49.25.34, 115.59.07.

Pighin Road

Two occupied sites were noted along Pighin Road. The site at the confluencewith Colt Road had a large stand of Rumex in a pasture with a prairie-likelandscape setting. Long-billed Curlews were even noted there to add to theprairie flavour of the landscape. Another site at kilometre 9 opposite an oldabandoned farmstead was also a pasture setting but had far fewer Rumex plantsthan the Colt Road site. Numerous other patches of Rumex were noted alongPighin Road and future work will certainly find some of them occupied byLycaena dione.

Figure 18. Map showing the approximate locations of the two occupied sitesfound on Pighin Road, north of Wycliffe (Latlongs 49.37.21, 115.52.24 and49.39.33, 115.54.08), at Wycliffe (latlong 49.36.16, 115.51.47) and Wycliffe-Mission Road (latlong 49.36.50).

15

Figure 19. View of part of the occupied site at Pighin road with junction of Coltroad.

16

Figure 20. Partial view of the occupied site at kilometre 9 of Pighin Road.

Wycliffe

One occupied site was found at Wycliffe (latlong 43.36.16, 115.51.47) andanother on a spur road just off the Mission-Wycliffe Road (latlong 49.36.30,115.51.00). See Figure 18, page 15 for a map. A nectaring female was found onalfalfa beside the townsite access road. Scattered plants and patches of Rumexare present in and around the townsite. Rumex was found to be very abundantlypresent throughout the ‘Wycliffe Prairie’ area, eg. along Pighin, Foster andWycliffe-Mission roads. It would take at least several days to contact landownersand check all the available sites for butterflies.

Figure 21. View of the roadside site just off the Mission-Wycliffe road.

17

DISCUSSION

Published reports of Lycaena dione using water smartweed (Polygonumamphibium) as a larval host plant are speculative and appear to be based on themistaken premise that Rumex is not available to the Confederation Parkpopulation (Guppy and Shepard 2001, Pyle 2002). Only the larger species ofRumex have been confirmed as a larval host. This field project has clearlydemonstrated that the butterfly flies in association with Rumex in dry anddisturbed/artificial habitats. Wetlands are not a factor in the distribution of thisbutterfly in BC except insofar as the shores of wetlands sometimes supportstands of Rumex.

The known biology of the butterfly also renders unlikely the successful use ofeither Polygonum or Rumex in spots subject to extended winter or springflooding. The eggs are laid on the Rumex plants and fall to the ground at thebase of the plant along with the dry plant parts in the fall. Eggs hatch in thespring and larvae then consume the new Rumex growth before they pupate andemerge in the summer as adults. Pupation is reported to occur in the litter at thebase of the Rumex plant (Pyle 2002). These are not aquatic organisms andneither the eggs nor larvae are known to be functional under extendedsubmergence. It is likely that if females chose Rumex growing in wet sites to laytheir eggs, that these plants would act as a population sink.

Trampling by livestock, if at very extreme and concentrated level, would likely beharmful to Lycaena dione populations. However, Kondla has observed apopulation on the prairie near Standard, Alberta for 30 years and the butterflieshave survived persistent heavy grazing and trampling around the Rumex plants.Normal livestock grazing in Lycaena dione habitat is certainly not a matter ofconcern

Trampling by humans at the Confederation Park site is not a problem at currentuse levels and management regime. Most people stay on the trails and simplydo not wander through the weedy areas. In particular, areas with thistles(frequently associated with Rumex) are avoided by the great majority ofrecreationists.

The main human activity that would be harmful to Lycaena dione would bemisguided weed spraying and misguided efforts to turn the necessary disturbedsites into ‘natural’ habitat. This butterfly is a ruderale and adventive species thatforms metapopulations and is well adapted to patchy and changing host plantconditions. Dispersal of individuals is most likely to be along linear corridors,both natural such as streams and also artificial corridors such as roadways andrailroad tracks. Weeds such as thistle should not be eradicated near Rumexstands because the nectar they supply to this and other butterflies is important

18

Besides responding well to direct human disturbance, Rumex distribution alsoappears to be affected by livestock activity. Rumex was frequently seen incorrals and other livestock enclosures and was also noted to be concentrated inthe shade of large trees where livestock are known to congregate for the shade.Examples of these phenomena are shown in Figures 22 and 23.

Figure 22. View of Rumex in livestock enclosure along Wycliffe-Mission Road.

Figure 23. View of Rumex concentration in shade of large tree frequented bylivestock.

Butterflies were found in sites where Rumex was present as relatively few plantsand also in large stands. Adults are strong fliers and clearly move widely through

19

their environment to locate Rumex. A viable metapopulation of this speciescould likely be maintained in the Cranbrook area of BC simply by ensuring thatvariable sized stands of Rumex continue to exist in the environment and by notkilling the flowering weeds that normally also grow in such sites. The sites withlarger stands of Rumex and persistent populations of the butterfly would be mostimportant to maintain as key habitat patches from which dispersers can populateor repopulate smaller sites (Etienne and Heesterbeek 2001).

Guppy and Shepard (2001) report yellow sweet clover (Melilotus officinalis) as anectar source for adults. In 2001 Kondla noted use of oxeye daisy(Chrysanthemum leucanthemum) and in 2002 nectaring was observed on alfalfa(Medicago sativa) and Canada thistle (Cirsium arvense). Most butterflies use avariety of nectaring sources as they are available.

The Flathead River valley was not searched due to time constraints but it ispossible that L. dione is resident there. Another Rumex-feeding species,Lycaena hyllus, has been reported from that area (Kondla et al. 2002). For timeand access reasons we also did not survey Kootenay Indian Reserve 1, whichlikely supports this butterfly. The north end of Lake Koocanusa has some Rumexpatches and these may be colonised by the butterfly during periods of lowerwater. These would then suffer extinction during years with high water levels.

The Confederation Park population is doing very well, in contrast to publishedconcerns about its welfare. The breeding area has a large interpretive signwhich provides high immediate profile to the provincial significance of thespecies. Local naturalists are also aware of the significance of the butterfly andso is the City of Cranbrook. There is sufficient local knowledge and interest tobode well for the future of this site as a breeding area for Lycaena dione.

Guppy and Kondla (2000) provided a provincial conservation status rank of S1(Critically Imperilled) on the basis of information available at the time. By usingthe same methodology and criteria plus this new information, we confirm thisprovincial conservation status rank. Although more local sites are known, theprovincial ranks are based on a conservative site definition using an approximate10 by 10 kilometre grid to define a site. Thus for ranking purposes the presentlyknown site count is 5. It is possible that further work would support a status rankof S2 (Imperilled).

Future field surveys are certain to locate additional occupied sites. It is plausiblethat more than 20 local sites of the kind described in this report will eventually befound. We expect that most additional sites would be found in the geographictriangle formed by Bummers Flats-Cranbrook-Kimberley. Total population is anunknown at this time and would require some mark/recapture studies or at leastformal transect counts to determine with any precision. Our best estimate is thatthe present population is between 1000 and 3000 adult individuals.

20

Oviposition by BC individuals has not yet been observed and it is thereforeunclear exactly which suite of Rumex species is being used by the butterfly.Rumex crispus was noted to be the most persistently present species atoccupied sites and in some of these sites was the only species so hence must bea larval host plant. It is also not known at this time what role if any ants play inthe life cycle of BC populations. Elsewhere at least a facultative version ofmyrmecophily is suggested through observations of ant attendance at feedingcaterpillars (Borkin 1993).

A final point of interest is the ventral appearance of the butterflies. Guppy andShepard (2001) describe the ventral color as being chalk white. The illustrationsprovided in said book are certainly quite white and have a bluish color to thebasal area of the wings. We do not know if this is due to the illustratedspecimens being aberrant or if the colors noted above are a result of thephotography process. We examined more than 20 specimens and found that themale ventral color is best described as light brown or beige in most casesalthough some are a light grey. Females tend to have a lighter venter, which canbe beige or a light whitish grey. Venters of several specimens are presented inAppendix 3 as figures 27 and 28 to illustrate the colors we observed. Theillustrations were generated from a scanner and are life size.

ACKNOWLEDGEMENTS

We thank the Columbia Basin Fish and Wildlife Compensation Program,Columbia Basin Trust, and Canadian Wildlife Service for funding that made thiswork possible. We also thank Crispin Guppy for providing peer review of a draftof this report and Susan Borkin for allowing use of her photographs.

LITERATURE CITED

Borkin, S. 1993. Investigating the Great Copper butterfly. Lore 43(2):16-19.Etienne, R.S. and J.A.P. Heesterbeek. 2001. Rules of thumb for conservation of

metapopulations based on a stochastic winking patch model. AmericanNaturalist 158:389-407.

Guppy, C.S. and N.G. Kondla. 2000. Status of the butterflies and skippers ofBritish Columbia for the National Accord for the Protection of Species at Risk.Prepared for Conservation Data Centre, Ministry of Environment, Lands andParks. 87 pp. + MS Excell spreadsheet.

Guppy, C.S. & J.H. Shepard. 1994. British Columbia's Butterflies and Moths in L.E.Harding and E. McCullum (editors). Biodiversity in British Columbia: OurChanging Environment. Environment Canada, Canadian Wildlife Service.

Guppy, C.S. and J.H. Shepard. 2001. Butterflies of British Columbia. Royal BCMuseum. 414 pp

21

Kondla, N.G., C.S. Guppy and J.H. Shepard. 2000. Butterflies of conservationinterest in Alberta, British Columbia, and Yukon. Pp. 95-100 in Darling, L.M.(ed.). Proceedings of a Conference on the Biology and Management ofSpecies and Habitats at Risk. Volume 1. BC Ministry of Environment, Landsand Parks and University College of the Caribou. 490 pp

Kondla, N.G., W.D. Nicholson, D. L. Threatful, C.S. Guppy, and B.C. Schmidt,.2002. Noteworthy British Columbia butterfly records. Boreus 22(1):17-24.

Pyle, R.M. 2002. Butterflies of Cascadia. Seattle, WA: Seattle Audubon Society.420 pp.

Shepard, J.H. (coordinator). 1990. Zone 2 Pacific Northwest: Idaho, Oregon,Washington, British Columbia in 1989 Seasons Summary. News of theLepidopterists’ Society 2(1990):14-15.

22

APPENDIX 1

Figure 24. Summary map of known Lycaena dione locations.

23

APPENDIX 2

Lycaena dione immature stage photographs. Susan Borkin images.

Figure 25. Mature larva (caterpillar).

Figure 26. Pupa.

24

APPENDIX 3

Figure 27. Venters of some male L. dione from the Cranbrook area.

Figure 28. Venters of some female L. dione from the Cranbrook area.