title: Distribution of Lepidopteran Larvae on Norway Spruce: Effects of Slope and Crown Aspect.
abstract: Lepidoptera associated with Norway spruce, Picea abies (L.) Karsten, play important roles in ecosystem processes, acting as plant pests, prey for predators, and hosts for parasites and parasitoids. Their distribution patterns in spruce crowns and forests are only poorly understood. We examined how slope and crown aspect affect the occurrence and abundance of moth larvae on solitary spruce trees in a montane region in Central Europe. Moth larvae were collected from southern and northern crowns of trees growing on south- and north-facing slopes (four treatments) using emergence boxes at the end of winter and by the beating method during the growing season. Species responses to slope and crown aspect were not uniform. Treatment effects on moth larvae were stronger in the winter than during the growing season. In winter, the abundance of bud-boring larvae was significantly higher in northern than in southern crowns regardless of the slope aspect, while both slope and aspect had marginally significant effects on abundance of miners. During the growing season, the occurrence of free-living larvae was similar among treatments. Emergence boxes and beating spruce branches are complementary techniques providing valuable insights into the assemblage structure of moth larvae on Norway spruce. Due to the uneven distribution of larvae detected in this study, we recommend adoption of a protocol that explicitly includes sampling of trees from contrasting slopes and branches from contrasting crown aspect in all seasons.
authors.affiliation: Institute of Forest Ecology, Slovak Academy of Sciences, Štúrova 2, 960 53 Zvolen, Slovak Republic (kulfan@savzv.sk; zach@savzv.sk; parak@savzv.sk), kulfan@savzv.sk.
authors.forename: Ján
authors.initials: J
authors.lastname: Kulfan
authors.affiliation: State Nature Conservancy SR, Administration CHKO Polana, J. M. Hurbana 20, 960 01 Zvolen, Slovak Republic (katarinka83@gmail.com).
authors.forename: Katarína
authors.initials: K
authors.lastname: Dvořáčková
authors.affiliation: Institute of Forest Ecology, Slovak Academy of Sciences, Štúrova 2, 960 53 Zvolen, Slovak Republic (kulfan@savzv.sk; zach@savzv.sk; parak@savzv.sk).
authors.forename: Peter
authors.initials: P
authors.lastname: Zach
authors.affiliation: Institute of Forest Ecology, Slovak Academy of Sciences, Štúrova 2, 960 53 Zvolen, Slovak Republic (kulfan@savzv.sk; zach@savzv.sk; parak@savzv.sk).
authors.forename: Michal
authors.initials: M
authors.lastname: Parák
authors.affiliation: Department of Biology and General Ecology, Faculty of Ecology and Environmental Sciences, Technical University in Zvolen, Masaryka 24, 960 01 Zvolen, Slovak Republic (svitok@tuzvo.sk), and Eawag Swiss Federal Institute of Aquatic Science and Technology, Department of Aquatic Ecology, Centre of Ecology, Evolution and Biogeochemistry, Seestrasse 79, CH-6047 Kastanienbaum, Switzerland.
authors.forename: Marek
authors.initials: M
authors.lastname: Svitok
mesh_terms: D063147:Animal Distribution; D000818:Animals; D017753:Ecosystem; D007814:Larva / Q000254:growth & development / Q000502:physiology; D009036:Moths / Q000254:growth & development / Q000502:physiology*; D028222:Picea / Q000254:growth & development; D018154:Slovakia; D014197:Trees / Q000254:growth & development
keywords: beating method; emergence box; forest herbivore; microhabitat; sampling