NOTES ON THE OWLET () OF SASKATCHEWAN

L.G. PUTNAM. 35 Kirk Crescent, Saskatoon, Saskatchewan. S7H 3B1

Among the , the Noctuidae, arose naturally from the predominantly drab night-flying Owlet several economically important species in¬ moths (Noctuidae) attract less attention cluded in the family. The important subter¬ than the glamourous day-flying butterflies. ranean cutworms are the Pale Western However, in Saskatchewan, the Noc¬ ( orthogonia Morr.), a pest of field tuidae comprise quite a long and varied crops in the open plains of the province, list of species. Their wing patterns and col¬ and the Red-backed Cutworm (Euxoa our variations, not to mention the more ochrogaster Gn.), a pest of crops in the subtle diagnostic characteristics ''Park Belt" and northerly areas, and a sometimes needed, suffice to interest and wide-spread pest of gardens. Among the challenge the specialist or hobbyist. climbing cutworms,the Bertha Armyworm (,Mamestra configurata Wlk.), a notorious The first list of noctuid species of Saskat¬ pest of the oilseed crops flax and canola, chewan known to the author was that is most notable. A pest of cereal grains, prepared (unpublished) by Dr. K.M. King, the True Armyworm (Pseudaletia unipunc- an early Officer-in-Charge of the Domi¬ ta Haw.) has been destructive locally from nion Entomological Laboratory at Saska¬ time to time. The same applies to the Flax toon. This arose out of material captured Boll worm ( ononis D. & S.), the during a lengthy period of light trapping Alfalfa Looper (Autographa californica begun in the 1920s. H. McDonald, Speyer) and the Clover Cutworm formerly of the same laboratory, con¬ (,Scotogramma trifolii Rott.). Several tinued light trapping in his own research species taken in Saskatchewan have rank¬ interests, thereby adding to the species ed as pests elsewhere but have been of records. With an intended focus on pests minor and infrequent consequence here. of brassicaceous oilseed crops (mostly (See Putnam and Burgess for photos of canola, or rapeseed as it was then known), some economic noctuids.3) the author operated a trapping station for a decade near the village of Aylsham, in The purpose of operating a light¬ the northeastern part of the Agricultural trapping station at Aylsham was less a part of the province, in the heart of a long- species survey than an abundance survey established rapeseed growing area. Five of economic species. Of the 210 noctuid species records new to Saskatchewan species identified from that point in the were added from this source, although decade, only 53 were taken in each of the these had been noted elsewhere in 10 years. The rest were identified as Western Canada. This brought the Saskat¬ follows (number of years taken, followed chewan list to about 342 species. That list by number of species in that category, in was by no means complete (R. Hooper, parenthesis): 9 yr. (25 spp.); 8 (10); 7 (11); pers. comm.). 6 (13); 5 (19); 4 (7); 3 (16); 2 (30); and 1 (26). Of those species captured in only The concern on the part of the workers four or fewer years of the 10, the average at the Dominion Entomological number per year per species was three or Laboratory, and later of those at the En¬ less; those caught every year averaged 92 tomology Section of the Agriculture per species per year. Presumably this dif¬ Research Station at Saskatoon with the ference reflects relative abundance,

164 Blue Jay although King pointed out that com¬ across the province in that year, did cap¬ parisons of abundance between species tures at Aylsham reach a total of 91. The on the basis of light trap captures may be general outbreak continued at about the invalid.2 same level in 1972, when 1,074 were captured using a more effective trap. The total annual captures of those Equivalent captures using the old-style trap species that were identified every year, or may reasonably be estimated at 250 to most years, varied widely within the 300. decade, consistent with population fluc¬ tuations typical of . None varied at King concluded that year-to-year dif¬ such extremes as the moths of the Red- ferences in captures of a given species backed Cutworm. This species was taken were indicative of actual population in larger total numbers than any other at changes,2 but, as we have seen in the Aylsham. The extremes were 3, in 1965, cases of the Red-backed Cutworm and the to 5834, in 1969. The latter figure con¬ Bertha Armyworm the meaning of such tributed by far the most to the 10-year total changes has to be interpreted on the basis of 7564. The trend was irregularly of the observer's experience with each downward from 1961 to '65, and upward species. from '65 to '69, crashing abruptly in 1970. Apparently, a decade is too brief a period All those species taken in excess of an to examine population trends exhaustive¬ arbitrary average of 50 per year were ly. Through the observations of isolated in a separate list, comprising 25 McDonald, it is known that the Red- species taken every year, plus one taken backed Cutworm is sensitive to soil sur¬ in 9 years. In addition to the Red-backed face conditions for oviposition, and that Cutworms the moths of several cutworms hatchling survival may be drastically af¬ common enough to have qualified for fected by soil moisture conditions. The common names somewhere, were includ¬ abundance of Red-backed Cutworms as ed in the list: The Dingy, Striped, Clover, noted at Aylsham, is in accord with its Bristly, Glassy, Early and Spotted Cut¬ status as a pest in the "Park Belt" and nor¬ worms. The Wheathead Armyworm, therly areas of Saskatchewan. On the other recorded as an outbreak species at least hand, the major subterranean cutworm of once in Saskatchewan, made the list. the open plains, the Pale Western was About eight other common-named cut¬ taken in seven years at about 4 moths per worm species were identified at year, confirming the long-alleged regional lower numbers. distinction. It is commonly accepted, as claimed by An apparently high abundance of Red- Guppy, that the True Armyworm cannot backed Cutworms during their flight winter in our latitudes, and therefore period may reflect a high larval popula¬ reaches Saskatchewan by immigration.1 It tion earlier in the spring of the same year, can produce two generations per season but it is not necessarily the result of an ex¬ here, and the second would normally tensive damaging outbreak. In the Bertha generate any larval outbreak occurring in Armyworm, abundance vs. scarcity has to cereals. If moths of this species immigrate, be judged in a frame of reference different a question arises as to how many other from that of the Red-backed Cutworm. In species detected at Aylsham might have the 10-year period, total annual captures been immigrants, at least into the district of Bertha Armyworm varied form 3 to 31. if not into the province. The data shed no Only after the decade proper, in 1971 in light on whether the species taken ir¬ the flight period preceding the "great" regularly and in small numbers were outbreak of 1971 in the rapeseed crops scarce permanent residents, or not suscep-

September 1986. 44(3) 165 tible to trapping, or casual invaders. Traps acquired first under the direction of Dr. using the more effective ultra violet H. McDonald, played an essential role in fluorescent lamps instead of the 100-watt the identification of material captured at incandescents used during the designated Aylsham. It is a pleasure to acknowledge decade might have shed some light on the his contribution. Resort was regularly had issue, but would have made it necessary to the reference collection of Noctuidae to examine about three times as many available at the Agriculture Canada specimens, not to mention a greatly in¬ Research Station at Saskatoon, where both creased bulk of "junk" insects. the author and Devlin were employed when the work described was under way. The order in which the species succeed each other in their first appearances at the 1 GUPPY, j.C. 1961. Life history and trap, from the beginning to the end of the behaviour of the army worm Pseudaletia season, is a separate subject. It will mere¬ unipuncta (Haw.) (Lepidoptera: Noctuidae) ly be noted here that among the first are in Eastern Ontario. The Canadian En¬ Lithophane thaxteri Grt. and Litholomia tomologist 93:1 141-1 153. napaea Morr. They are also among the last to appear in the fall, and therefore may 2 KING, K.M. 1940. The light trap as an in¬ be considered to winter in the moth dicator of population trends in Noc¬ stage.* Most other species in Saskat¬ tuidae. Ph. D. Thesis, University of Min¬ nesota (Unpublished). chewan have a diapause in the egg, lar¬ val or pupal stage, and hibernate in one 3 PUTNAM, L.G., and L. BURGESS. 1979. of those. pests of rape and mustard. In: Insect pests and diseases of rape and mustard. Mr. C.G. Devlin, Technician, using the Rapeseed Association of Canada Publ. No. skills in the of the Noctuidae 48.

* These species are in the subfamily Cucullinae. A number of other species in the same subfami¬ ly overwinter as adults in Saskatchewan, especially those in the following genera: Lithophane, Eupsilia, Xylena and Homoglaea. These can be collected as adults in both October and April. The provincial total for noctuid species now stands at 523. — R. Hooper

VARIEGATED FRITILLARY whole of the United States and most of Canada to reach The Pas in late June or BREEDING AT THE PAS, early July. These are rare visits. Several MANITOBA years go by without one being seen. These migrants are small, worn examples which WALTER KRIVDA, Box 864, The Pas, can be seen on the wing for a few weeks. Manitoba. R9A 1K8 They feed at dandelion blossoms.

There are only two species known in the Now and then a few specimens can be Euptoieta — E. hegesia and E. netted in The Pas area of a locally produc¬ claudia. The first is a jungle butterfly rang¬ ed generation — originating from the eggs ing into the United States. The second, the laid by the southern visitors. These are Variegated Fritillary, also originates in the large dark specimens often remarkably new world tropics but migrates across the mottled on the underside. Such specimens

166 Blue Jay