Density-Dependent and -Independent Behaviors of the Adult Karner Blue (Lycaeides Melissa Samuelis) (Lepidoptera: Lycaenidae)

At 146 pine-oak barrens in central and northwestern Wisconsin USA during 1988-96, 3973 Karner blues (Lycaeides melissa samuelis Nabokov) were found in 95.4 hr of transect surveys during spring and 6896 individuals in 134.8 hr during summer. Of these, 9346 (86%) individuals were first observed copulating, feeding, flushing, flying, or involved in a non-copulatory intraspecific interaction. All these behaviors except copulation showed density-independent influences; all these behaviors also had density-dependent influences. The most frequently significant density-independent variables affecting occurrence of these behaviors were temperature, brood (spring vs. summer), and crepuscularity (time since noon). Male (rather than female or overall) Karner blue density more often significantly related to Karner blue behavior. Males showed density dependence in feeding (positive), flushing (negative), and flying (positive threshold) while females did not. Both sexes showed strong positive density dependence in non-copulatory intraspecific interactions and copulation. Flying and intraspecific interactions showed similar influences in relation to several variables, while flying and flushing had markedly opposite patterns. Males and females were also opposite in their relative tendency to be observed flushing or flying, with females more likely to be flushing, males flying. Males also showed a greater tendency to engage in non-copulatory intraspecific interactions

Variation in Timing and Abundance of Elfins (Callophrys) (Lepidoptera: Lycaenidae) in Wisconsin During 1987-1999

In Wisconsin during 1987-1999, we recorded elfin (Callophrys) individuals on 154 of 254 observation dates between 2 April and 11 July. The frosted elfin (C. irus) occurred only in central Wisconsin; brown (C. augustinus), hoary (C. polios), and Henry\u27s (c. henrici) elfins in central and northern Wisconsin; and eastern pine elfin (C. niphon) from southern to northern Wisconsin. Most individuals were eastern pine elfins, which occurred at the most sites, while Henry\u27s elfin had the fewest individuals and sites. All five elfins occurred in the most frequently visited subregion (central Wisconsin), where they all had similar median and mean observation dates for all study years pooled. For most elfins, the number of individuals observed per year covaried significantly with the span of days between first and last observation dates that year. Within species, mean and median observation dates in the earliest year(s) always occurred before the first observation date in the latest year(s). We compared the phenology of the frosted elfin flight period to the timing of olympia marble (Euchloe olympia) adults and spring Karner blue (Lycaeides melissa samuelis) larvae and adults. The least variable relationship was the date of first mature Karner larva (typically before first frosted elfin adult, and bracketing that date by only 8 days). Only the frosted elfin showed a significant influence of weather (temperature only) on observed density, while most elfins significantly increased the nearer to noontime. We recorded elfins in broad ranges of weather conditions and daily timing. Elfin abundance fluctuated markedly among years based on the mean of peak survey totals at the same monitoring sites in central Wisconsin each year from 1992 or 1993 to 1999. One outlier site each for frosted and eastern pine elfins had much higher peak survey totals than the other sites. Abundance fluctuations in the outlier and other sites did not correlate significantly for either species. For most elfins, the percent sites where the species was recorded as present each year covaried significantly with that year\u27s annual mean of peak survey totals. This indicates that the ability to document presence of an elfin relates to the species\u27 abundance that year. Since elfin abundance and flight timing and length varied considerably among years, the appropriate time for elfin detection must be determined individually for each year and assessments of an elfin\u27s status and abundance cannot be reliably based on surveys at only a few sites or in a few years

Factors Affecting Abundance of Adult Karner Blues (\u3ci\u3eLycaeides Melissa Samuelis\u3c/i\u3e) (Lepidoptera: Lycaenidae) in Wisconsin Surveys 1987-95

At 141 pine-oak barrens in central and northwestern Wisconsin, 3,702 Karner blues (Lycaeides melissa samuelis Nabokov) were found in 81.1 hr of transect surveys during spring and 6,094 individuals in 116.6 hr during sum­mer. Adults offive other closely related lycaenids occurred with Karner blues. The percentage of Karner blue males (of sexed individuals) correlated nega- tively with advancing date within brood, exceeded 50% on peak date within brood, but showed wide variability on a given date. Karner blues occasionally occurred up to 800 m from the nearest larval host, or in tiny, isolated host stands. However, all individuals were within 3-5 km of other larger Karner blue populations. Karner blue abundance significantly increased with decreasing latitude, increasing temperature, nearness to midpoint within brood, decreasing site canopy, increasing larval host abundance, and in summer compared to spring. Long-term monitoring sites showed dramatic but relatively similar fluctuations among broods (median of 2.8-fold change among ten brood pairs) that apparently varied by individual brood rather than season or year. Extensive dense host patches and dense Karner blues were in sites rep- resenting a diversity of management histories

Variation in Detecting \u3ci\u3eSchinia Indiana\u3c/i\u3e and \u3ci\u3eSchinia Lucens\u3c/i\u3e (Lepidoptera: Noctuidae) in Wisconsin

Schinia indiana (Smith) and Schinia lucens (Morrison) (Lepidoptera: Noctuidae) are diurnal moths and are well camouflaged when perched on flowers of their larval food plants: Phlox pilosa L. (Polemoniaceae) and Amorpha(Fabaceae), respectively. We recorded 264 S. indiana in diurnal surveys of 28 units of 15 sites in Jackson County, WI, and 25 units of 5 sites in Burnett County, WI, from 23 May (2006) to 15 June (1994). The longest flight periods in single years were 21 days in 1994 and 17 days in 2006. Abundance of individuals was significantly greater when phlox flowering was prepeak and peak, compared to earlier and later in phlox flowering phenology. We recorded 46 S. lucens in diurnal surveys of nine sites in six counties in southern Wisconsin and two sites in two counties in northwestern Wisconsin, from 30 June (1998) to 29 July (2002). The longest flight periods in single years statewide were 23 days (2002) and 15 days (2000). One S. indiana flushed at 16oC, but all other flushes occurred when it was \u3e 20oC, and after 7:41 hr CST. Nonetheless, we detected many S. indiana after these flushing thresholds had been reached. S. indiana was significantly more likely to move and to flush when it was warmer, sunnier, or later in the day. By contrast, S. lucens was not significantly more likely to be active when it was warmer, sunnier or later in the day. Both species showed considerable fluctuation in abundance among years. For detecting S. indiana, sunny conditions at any time of day when it is \u3c 16oC appear ideal, followed by sunny and \u3c 20oC. When S. indiana individuals are active, it is still possible to find them if great caution is taken in approaching phlox flowers, especially by using binoculars to search phlox flowers. Effective diurnal surveys for S. lucens may occur in a broad range of weather and time of day

Timing of Karner Blue (Lepidoptera: Lycaenidae) Larvae in Spring and Adults in Spring and Summer in Wisconsin During 1991-1998

During 1991-1998, formal surveys and incidental observations of the Karner blue (Lycaeides melissa samuelis) (Lepidoptera: Lycaenidae) occurred on 2-8 dates each year for spring larvae and on 5-10 dates in each adult generation at 148 pine-oak barrens in ten counties of central and northwestern Wisconsin. A total of 493 spring larvae were recorded, as well as 16,039 adults (6755 in spring and 9284 in summer) in 375.5 hours of formal adult survey effort. Adult Karner blue timing varied among years by about 2-5 weeks in spring and 2.5-6 weeks in summer. The mean span between spring and summer adult generations was about 46 to 50 days for all sites pooled. In some years, Karner blue phenology appeared to speed up or slow down relative to this average span between generations. At six sites surveyed for spring and summer adults in the same 5 years, the mean date of maximum adults differed among sites by about 9.5 days in spring and 6 days in sum­mer. These sites varied in the consistency of their relative phenology (early, average, or late) between spring and summer. Consistent sites changed relatively little in shading from spring to summer because canopy was sparse or primarily evergreen. Variable sites changed in degree of insolation between spring and summer, because of the leafing out of deciduous canopy or the higher angle of the summer sun rising above the surrounding forest more. Four kinds of variability should be considered in assessments of Karner blue phenology: (1) intergenerational fluctuations in abundance, (2) phenological differences among years and (3) among sites, and (4) interannual variation in span between spring and summer generations

Observations of Prairie Skippers \u3ci\u3e(Oarisma Poweshiek, Hesperia Dacotae, H. Ottoe, H. Leonardus Pawnee\u3c/i\u3e, and \u3ci\u3eAtrytone Arogos Iowa\u3c/i\u3e) [(Lepidoptera: Hesperiidae] in Iowa, Minnesota, and North Dakota During 1988-1997

In transect butterfly surveys at 40 prairies in Iowa, Minnesota, and North Dakota in summer each year during 1988-1997, we recorded 2403 adults of Poweshiek skipperling (Oarisma poweshiek) at 20 sites, 547 Dakota skippers (Hesperia dacotae) at 12 sites, 27 Ottoe skippers (H. ottoe) at one site, 290 Pawnee skippers (H. leonardus pawnee) at eight sites, and 81 Arogos skippers (Atrytone arogos) at nine sites. In correlations of relative density (individuals/km) of the analyzable species (all but Ottoe skipper), geographical factors (latitude and longitude) produced the most significant correlations, followed by timing (with higher numbers nearer noontime), and lastly weather (positive correlation with temperature, negative correlation with wind speed). The relative densities of these analyzable species showed more significant differences in relation to habitat factors than to variables describing diurnal activity patterns or weather conditions. Relatively higher skipper densities occurred in drier, undergraded prairie vegetation in sites with diverse rather than uniform topography. Patterns of relative density also varied among species with respect to management by idling, grazing, haying, or burning. Nectar visits by species, and by sex if possible, are reported. More instances of courtship rejection than mating were observed. On later dates in the flight period, female Dakota skippers proportionately increased and the sex ratio became more variable. With increasing relative density, the sex ratio of Dakota and Pawnee skippers became less variable and tended to- ward values in the range of about an even ratio

Habitat Associations of Sympatric Violet-Feeding Fritillaries (Euptoieta, Speyeria, Boloria) (Lepidoptera: Nymphalidae) in Tallgrass Prairie

At 106 tallgrass prairies in the midwestern USA, 18,055 individuals of six fritillary species (Lepidoptera: Nymphalidae) were counted in 552.9 hr and 987.1 kill of transect survey effort from 14 June to 13 September during 1988-96. The relative abundance of Euptoieta claudia, Speyena cybele, S. aphrodite, S. idalia, Boloria selene, and B. bellona was analyzed for significant patterns relative to five habitat factors. Topographic diversity (i.e., whether the site was uniform or contained both uplands and lowlands) produced the most significant effects. Prairie patch size and vegetation type (wet, mesic, dry) also produced numerous significant patterns. When management type was significant, burning alone or in combination with another management was associated with lower densities, non-management with intermediate or higher densities, haying and grazing with higher densities. Vegetative quality (i.e., degree of floristic degradation) produced the fewest significant patterns. Three of four testable fritillary species significantly and positively correlated in abundance with one or more species of Viola (Violaceae) (violets). Most correlations were with particular violet species, not combined violet abundance, suggesting that the fritillaries segmented violet resources (their larval food) by species and/or habitat. The two most abundant violet species, V. pedata and V. pedatifida, and violets in general, oc­curred in more sites than any of the fritillary species did. The species most restricted to tallgrass prairie, S. idalia, was relatively denser in dry prairie vegetation in larger prairie patches with topographic diversity and management by haying or grazing

Observations of \u3ci\u3eIncisalia Irus\u3c/i\u3e (Lepidoptera: Lycaenidael in Central Wisconsin 1988-95

In surveys conducted during 1988-95, 164 individuals of the frosted elfin (Incisalia irus) were found, 139 of them during formal transects that totaled 92.9 hr and 179.4 km of survey effort during the frosted elfin flight period. Individuals were observed between 10 May and 14 June, with maximum . t spans in a single year of 27-31 days. Peak flight occurred just before or e beginning of peak flowering of the larval host, wild lupine (Lupinus perennis), and the first spring adults of Karner blue (Lycaeides melissa samuelis), also monophagous as larvae on wild lupine. Fourteen individuals exhibited oviposition behavior on young stalks of green lupine flower buds. 94% of individuals occurred in savannas, nearly evenly split between open (10-24% canopy) and closed (25-49% canopy) ones. Relative lupine abundance at both the microsite and landscape scales appeared more important as a habitat factor than actual size of the particular lupine patch occupied. Both long-term lack of site management and too frequent/intense management (forestry, rotational fire) appeared unfavorable. Recreational trailsides, areas burned by wildfire \u3e4 years ago, and rights-of-way mowed annually or less often were favorable habitat. All frosted elfin sites also supported Karner blues, but within these sites, correlation of frosted elfin abundance with that of Karner blues was rather weak, indicating a fair degree of niche segregation between these two species

Observations of Spring Larvae of \u3ci\u3eLycaeides Melissa Samuelis (Lepidoptera: Lycaenidae) in Central Wisconsin

At 36 sampling sites in central Wisconsin 1991-94, 358 spring larvae of the Karner blue (Lycaeides melissa samuelis) ranged from 1.9-17.0 mm in length, with only two \u3e15.0 mm. The number of attending ants (mean 2.0, range 0-25) covaried strongly with larval size, with ants attending all larval instars. Height of wild lupine (Lupinus perennis), this butterfly\u27s only larval food plant, correlated significantly with larval length, and larvae did not appear to hatch too soon in cool springs to have adequate forage. Larval presence and size correlated significantly with five of seven types of feeding signs on the lupines. Larval perching sites, feeding locations, and disturbance behaviors varied somewhat by instar. In 1991-93, no larvae were found in seven samplings of recently burned areas, although larvae were found in unburned sites nearby. In 1994, two larvae were found in a very patchily and incompletely burned area. Many larvae were found in areas mowed since or during the previous adult flight. Larval counts correlated positively with adult counts later in the same year. Adult surveys appeared more efficient than larval surveys, which are more effective when based on a knowledge of larval phenology, feeding signs, perching sites, feeding locations, and disturbance tolerances

Spatial Synchrony in Wisconsin Karner Blue (Lepidoptera: Lycaenidae) Populations

We analyzed geographic patterns of Karner blue (Lycaeides melissa samuelis Nabokov, Lepidoptera: Lycaenidae) population fluctuations in summer broods in central and northwestern Wisconsin and spring+summer broods in central Wisconsin. We removed possible effects of population trends by analyzing residuals from a regression of each site’s population index vs. year. We then calculated correlation coefficients (r) of these residuals for all site-pairs separately for 1992- 2005 (26 sites, N = 325 site-pairs), 1995-2005 (21 sites, N = 210), and 1998-2005 (14 sites, N = 91). We analyzed patterns in these r values relative to distance between sites using correlations vs. distance and using pairwise comparisons of different distance categories (0-3 km up to 223-264 km apart). Karner blues showed significant (P \u3c 0.05) population synchrony over all distances. Spatial autocorrelation was strongest among sites \u3c3 km apart, then gradually leveled off at greater distances. Statistical power increased when we added three years but the number of sites did not decrease greatly (1995-2005 vs. 1998-2005 analyses) and when using an annual index combining spring+summer indices instead of just summer. The spatial autocorrelation extending over the entire study region suggests that environmental factors like weather provide some synchronization of Karner blue populations. Their much higher local synchrony is consistent with the species’ short dispersal distance. Their local and regional spatial autocorrelation increases the likelihood of correlated local extinctions during low fluctuation broods, especially when these coincide with unfavorable weather or adverse habitat events