ORIGINAL PAPER The effect of reduced-impact logging on fruit-feeding butterflies in Central Amazon, Brazil Danilo B. Ribeiro • Andre ´ V. L. Freitas Received: 28 March 2011 / Accepted: 18 January 2012 / Published online: 31 January 2012 Ó Springer Science+Business Media B.V. 2012 Abstract The Amazon region represents more than a half of all tropical forests in the world, and has been threatened by many anthropogenic activities, including several kinds of timber harvesting. The reduced-impact logging (RIL) is considered a less destructive method of timber harvesting, but there is a general lack of information about the effects on Amazonian invertebrates, including butterflies. We investigated the effect of RIL on fruit-feeding butterflies by comparing canopy and understory between an area under RIL and a control area without RIL. The canopy fauna is different and significantly richer than the understory fauna, showing that sampling only the lower strata underestimates the diversity of fruit-feeding butterflies. The effects of RIL were mainly detected in the understory butterfly assem- blage, as significant differences were observed in species composition within this stratum. Effects of the RIL regime, which include tree cutting, skid trails and roads openings, are stronger in the understory than in the canopy, explaining the reported differences. Despite the detectable effects of RIL on the composition of fruit-feeding butterfly assemblages, the overall diversity was not affected. A similar pattern has been detected in many other groups, indicating that a noticeable part of the diversity of many taxa could be preserved in areas under RIL management. Therefore, in view of the problems of creating protected areas in the Amazon, RIL is a good alternative to preserve fruit-feeding butterflies and surely many other taxa, and it might be a desirable economic alternative for the region. Keywords Canopy Á Ecological indicators Á Forest degradation Á Nymphalidae Á Tropical Á Understory Introduction The Amazon region represents 60% of all tropical forest areas in the world (Lovejoy 1999). A total of 6,451 km 2 was cleared, and additional 13,301 km 2 suffered logging activities of different intensities from August 2009 to August 2010 (INPE 2010; Sist 2000). The major causes of forest degradation in the Amazon are the understory fires and timber extraction (INPE 2010). Timber extraction can be done, without clear cutting, in two basically different ways: (1) conventional logging, where most individuals of the species of high economic value are removed, without previous planning, and (2) reduced-impact logging (RIL) were only few individuals are removed per hectare using techniques to reduce the impact of timber extraction in the remaining vegetation (Sist 2000; Laurance et al. 2005). Most of the logging activities in the tropics are con- ducted by untrained and unsupervised crews without pre- vious planning, and this implies in several impacts in the remaining vegetation and high levels of injuries to the workers (Putz 2008). Traditional selective logging affects several different groups of organisms (Johns 1985; Azev- edo-Ramos et al. 2006; DeVries et al. 1997; Devy and Davidar 2001; Dumbrell and Hill 2005) and heavily changes the structure of the remaining forest (Gerwing 2002). This also causes changes in the physical environ- ment, including soil compaction, and light incidence in the D. B. Ribeiro Programa de Po ´s-Graduac ¸a ˜o em Ecologia, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, Brazil D. B. Ribeiro (&) Á A. V. L. Freitas Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas, P. O. Box 6109, Campinas, Sa ˜o Paulo 13083-970, Brazil e-mail: biodbr@yahoo.com.br; baku@unicamp.br 123 J Insect Conserv (2012) 16:733–744 DOI 10.1007/s10841-012-9458-3