o .eg an Jo of En1tomol0lD' - Norsk entomologisk forening

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Table 7. Foodplants of the dominant Macrolepidotera on northern Sotra. (P) indicate that a species is polyphagous. SPECIES Geometridae Xanthorhoe designata Entephria caesiata Cosmorhoe ocel/ata Eu/ithis testata E. popu/ata Thera cognata T. juniperata C%stygia pectinataria Hydriomena Jurcata Perizoma minorata P. didymata Eupithecia intricata E. nanata E. pusi//ata ftame wauaria Pachycnemia hippocastanaria Crocallis e/inguaria C/eora cinctaria A/cis repandata Gnophos obJuscata Foodplants Cruciferae (Cardamine pratensis) Ericaceae Ga/ium Cal/una, Vaccinium u/iginosum (P) Vaccinium myrti//us, Sa/ix (P) Juniperus Juniperus Ga/ium (P) Vaccinium myrti//us, Sa/ix Euphrasia Vaccinium myrti//us, herbs (P) Juniperus Cal/una Juniperus Ribes Cal/una hardwoods (P) hardwoods, herbs, Ericaceae (P) hardwoods, Ericaceae (P) herbs, Ericaceae (P) J Noctuidae Euxoa obe/isca Rhyacia grisescens Chersotis cuprea Noctua pronuba N. comes Paradiarsia g/areosa Lycophotia porphyrea Diarsia mendica Xestia castanea X. xanthographa Cerastis rubricosa Ceramica pisi Cerapteryx graminis Orthosia gothica Aporophy/a nigra Amphipyra tragopoginis Apamea monog/ypha A. /ateritia A. furva Photedes minima Amphipoea /ucens A. crinanensis Hydraecia micacea Ce/aena haworthii Sti/bia anoma/a herbs, grasses (P) herbs, grasses (Pl herbs, (Pl herbs, (P) herbs, (P) herbs, Cal/una, Sa/ix (P) Cal/una herbs (P) Cal/una, Vaccinium myrtil/us (P) herbs, grasses (P) herbs (P) herbs, hardwoods, grasses (P) grasses (P) herbs, hardwoods (P) herbs, grasses (P) herbs, hardwoods (P) grasses (P) grasses (P) grasses (P) grasses, sedges (Pl herbs on swampy ground (P) herbs on swampy ground (P) herbs and sedges on swampy ground (P) sedges (P) Ericaceae of the catches in this habitat compared to 31 % on the grassland. More likely the high number of Noctuidae species taken in the heath is connected with the fact that many of the West Norwegian Noctuidae are polyphagous and hence have the possibi· lity to find foodplants in the heath. The foodplants of the dominant species, mainly according to Nordstr6m et al. (I 94 0, are listed in Tab. 7. The dominant Noctuidae, Lycophotia porphyrea, feeds on Calluna, and this plant is also the foodplant for several of the dominant Geometridae species, like Pachycnemia hippocastanaria and Eupithecia nanata, (Hiibner, 1813) and also 102
Ematurga atomaria. Other species of Ericaceae, Vaccinium myrtillus, V. vitis-idaea, Erica tetrafix etc., also is important as foodplants for a high number of the Macrolepidoptera inhabiting the heath. Various grasses and sedges serve as foodplants for many of the dominant Noctuidae, like Cerapteryx graminis, Apamea monoglypha, Amphipoea lucens and Celaena haworthii, while several of the dominant Geometridae, like Thera cognata, T. juniperata, Eupithecia pusillata and E. intricata (Zetterstedt, 1839) feed on Juniperus. Juniperus grows abundantly both in the heath and on the grassland and the importance of this plant as a food plant is reflected in the high similarity between the Geometridae faunas in the two habitats, shown by Renkonen's percentage of similarity. The bimodality in the total catch, with largest catches in spring and late summer might be a result of reduced efficiency of the traps during the short and bright middsummer nights. Light traps catch insects because the high illumination ofthe traps relative to the surroundings interfers with the normal photic orientation of the insects. Anything that reduces the contrast will have the effect of reducing the catch (Verheijen 1960). In Western Norway light traps must therefore be expected to be more efficient during the long dark nights in the spring and towards the autumn than during the middsummer nights (cf. Ulfstrand 1970, Southwood 1975). High • background illumination might also have a direct effect. Moonlight depresses flight activity in insects (Williams 1936, Williams and Singh 195 I), and Persson (} 971) indicated that also the normal night light in June might lower flight activity. In any ease, in the open, flat terrain on northern Sotra the background illumination in • middsummer must be particularly noticeable. The flight periods of the dominant species show a high degree of overlap with the flight periods recorded for the species elsewhere in Southern Norway and in England (e.g. Bakke 1974, Williams 1939). Proceeding from south towards north on the northern hemisphere the flight periods of «vernal» species occur progressively later with increasing latitude, and conversely for the «autumnal» species (Wiltshire 1938, 1941 a,b). Hardwick (I 97 I) has shown that a «phenological date» can be calculated for each species, considering the lenght of the summer in a given locality (actually the number of days with a temperature above 42°F). When comparing the time and duration of the flight periods of the dominant species on northern Sotra with their flight periods in other areas both the locality's northernly possition and the effect of the atlantic climate have to be taken into account. An uneven sex-ratio is often experienced in light trap catches and most often reflects differences in trappability between the sexes due to variation in phototactism and activity pattern. For some species there also are differences in flight potential between the sexes. The sex-ratio obtained in light trap catches seems, however, to be rather stable for many Noctuidae species. Williams (I 939) recorded f. inst. 9 % females in Xestia xanthographa, 11 % in C. graminis and 25 % in A. monoglypha. The corresponding sexratioes in the light trap catches on northern Sotra were 10%, 12 % and 28 %, respectively. The tendency of the males to arrive a few days earlier than the females, i.e. protandry, has been experienced in light trap catches of different insect groups (e.g. Svensson 1972). Wiklund and Fagerstrom (I 977) suggested that protandry is the optimal reproductive strategy of males in species maintaining female monogamy, or in species in which sperm from males mating with virgin females on the average fertilizes a larger number of eggs than sperm from males mating with already mated females. In areas where the heaths are burned regularly Juniperus will disappear (Gimingham 1976), and the Macrolepidoptera community in a well tended heath will accordingly contain fewer species than recorded here for the heaths on northern Sotra. However, the altered farming habits in Western Norway have led to the spreading of woody plants in the heaths, and a number of herbs will in time undoubtedly invade the heaths. As a greater variety of plants generally leads to a greater variety of plant-eaters (Murdoch et a1. 1972), a gradual higher diversity in the Macrolepidoptera community in the heaths is to be expected as an increasing number ofspecies will find suitable foodplants. On the other hand, if the attempts to vegetate the West Norwegian lowland heaths with foreign conifers is successful, the opposite trend will undoubtedly be experienced. ACKNOWLEDGEMENTS I am greatly indebted to A. Fjeldsa for advise and help during all stages of the study. My thanks are also due to P. Andersen and W. Nielsen for assistance during the fieldwork, to M. Bravo for technical assistance and typewriting, and to T. Solh0y for valuable comments on the manuscript. Financial support was received from the Norwegian Research Council for Science and the Humanities (NAVF) and from Norwegian Statoil.
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2 o .eg an Jo OL2 of En1tomol0lD'
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Carabidae and Staphylinidae (Col.)
Page 5 and 6: Table l. Mean activity density, giv
Page 7 and 8: JEU'lY As SKI Activity Species 1975
Page 9 and 10: Table 4. The 10 most numerous staph
Page 11 and 12: 1 .. ... · • a. a. · .. • a.
Page 13 and 14: .. ...• ~ • a. a. · · ~ = •
Page 15 and 16: - (Red.) 1960. Catalogus Coleoptero
Page 17 and 18: Dyschirius septentrionum is a regul
Page 19 and 20: J sparsely vegetated fallow land wi
Page 21 and 22: Table 2. The abudance (number per 0
Page 23 and 24: Records of nine species of Ophionin
Page 25 and 26: 1972, 4Q Q, 4-15 Oct. 1972, 2Q Q, R
Page 27 and 28: Table I. Bumblebee nests from two d
Page 29 and 30: Hydroporus erythrocephalus (L.). MR
Page 31 and 32: delse i Norge, og er tidligere ikke
Page 33 and 34: -. Table I. Localities. Abbreviatio
Page 35 and 36: Hr., Jt., Pf. I June-4 July, abunda
Page 37 and 38: ler, 1775)]t. 3 and 18 Aug. 2 d, I
Page 39 and 40: Some studies on Macrolepidoptera in
Page 41 and 42: een planted, mostly as single trees
Page 43 and 44: Table 2. Relative abundance ( + , +
Page 45 and 46: SPECIES Grassland Cal/una heath 0 9
Page 47 and 48: Table. 4. Additional Macrolepidopte
Page 49 and 50: 50 50 30 10 . .~ "' Q. . , '" 30 1
Page 51 and 52: Ent.phn. ' ••.f,.ta Perl~oma ri
Page 53 and 54: C.r"5tl~ fubricosa Amplllpyrd "agop
Page 55: Table 6. Sex ratio and median day o
Page 59 and 60: Survey of the Pine Beauty Moth Pano
Page 61 and 62: Fig. 2. Trap model. (Copied from Bo
Page 63 and 64: the results indicate certain differ
Page 65 and 66: terestingly, the lepidopterous host
Page 67 and 68: Material: Raubekken 900 m I Q 17 Ju
Page 69 and 70: Chironomidae (Dipt.) from Ekse, Wes
Page 71 and 72: SYSTEMATIC LIST Podonominae Parochl
Page 73 and 74: Prodiamesinae Prodiamesa olivaeea (
Page 75 and 76: Edwards, F.W. 1922. Results of the
Page 77 and 78: In the species-list previously publ
Page 79 and 80: Kauri (966) mentions it from SFi: A
Page 81 and 82: 0kland, F. 1939. En vesteuropeisk O
Page 83 and 84: Table I. Ecologicel notes.Meterial
Page 85 and 86: 4.MEGABUNUS DIAOEMA 5. RIL.'IiHA TR
Page 87 and 88: IO.L.A&INIL6 EPHIPPIATla II.MITOPU6
Page 89 and 90: ( Short communiCatiOns) THE FUNGIVO
Page 91 and 92: GUIDE TO AUTHORS. FAUNA NORVEGICA S
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