Spatial Patterns of Movement of Dung Beetle Species in a Tropical Forest Suggest a New Trap Spacing for Dung Beetle Biodiversity Studies

May Spatial Patterns of Movement of Dung Beetle Species in a Tropical Forest Suggest a New Trap Spacing for Dung Beetle Biodiversity Studies Pedro Giovni da Silva 0 1 Malva Isabel Medina Hernndez 0 1 0 Programa de Pos-Graduacao em Ecologia, Departamento de Ecologia e Zoologia, Universidade Federal de Santa Catarina , Florianopolis, Santa Catarina , Brazil 1 Academic Editor: Alex Cordoba-Aguilar, Universidad Nacional Autonoma de Mexico , MEXICO A primary goal of community ecologists is to understand the processes underlying the spatiotemporal patterns of species distribution. Understanding the dispersal process is of great interest in ecology because it is related to several mechanisms driving community structure. We investigated the mobility of dung beetles using mark-release-recapture technique, and tested the usefulness of the current recommendation for interaction distance between baited pitfall traps in the Brazilian Atlantic Forest. We found differences in mean movement rate between Scarabaeinae species, and between species with different sets of ecological traits. Large-diurnal-tunneler species showed greater mobility than did both large-nocturnal tunneler and roller species. Our results suggest that, based on the analyses of the whole community or the species with the highest number of recaptured individuals, the minimum distance of 50 m between pairs of baited pitfall traps proposed roughly 10 years ago is inadequate. Dung beetle species with different sets of ecological traits may differ in their dispersal ability, so we suggest a new minimum distance of 100 m between pairs of traps to minimize interference between baited pitfall traps for sampling copronecrophagous Scarabaeinae dung beetles. - Data Availability Statement: All relevant data are within the paper and its Supporting Information files. Funding: This study is part of the Project Biodiversidade de artrpodes terrestres e aquticos em diferentes gradientes ambientais da Mata Atlntica do estado de Santa Catarina, and was supported by Coordenao de Pessoal de Nvel Superior (Proc. 001/2010 MEC/CAPES/PNPD). PGS received a post-graduate fellowship from Coordenao de Pessoal de Nvel Superior. MIMH received a research grant from Conselho Nacional de Desenvolvimento Cientfico e Tecnolgico (Research Productivity/PQ/2010, Proc. 303800/2010-0, Project Understanding the patterns of the spatiotemporal distribution of species is still a challenge for community ecologists. Dispersal is the capacity that organisms have to move over space, and is one of the four basic ecological processes driving such patterns [1]. This process is of great interest in ecology and evolution, because it is related to population and community dynamics, gene flow, speciation and extinction processes [2]. Dispersal is affected by several factors such as the ability to move through the landscape, perceptual resolution (shortest distance to detect resources), quality and distribution of the resource, and internal and external stimuli [3]. Species with dissimilar morphological and functional traits may have other resource requirements, Comportamento de besouros Scarabaeinae e sua funo no ciclo de decomposio da matria orgnica). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. and thus may have different rates of dispersal. Species with individuals who have higher dispersal ability may strongly alter the structure of local communities via patch dynamics or mass effects [4]. Dispersal was the key point for the development of metacommunity theory. A metacommunity is a set of local communities linked by the dispersal of multiple species [4, 5], and is primarily concerned with the role of dispersal between local communities in generating patterns of composition, abundance and species richness at multiple spatial scales. Understanding species dispersal processes is critical in current scenarios of habitat loss, fragmentation and global climate change [6]. The study of ability for movement by different organisms such as dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae), which play key roles in the maintenance and restoration of ecosystems, is an important starting point for planning of conservation strategies. Dung beetles are a very diverse group of detritus-feeding insects that have several ecological functions [7]. The diversity of the group is reflected in differences in body size [8, 9], body shape [10], resource relocation behavior for feeding and nesting [11, 12], and diel activity period [13, 14], for example. Dung beetle species may respond in different ways to alteration, disturbance, fragmentation, and loss of habitat [15], and as such they may be used as environmental indicators [1618]. Several species from Neotropical forests exhibit varying degrees of habitat specificity, with many environmental specialists and generalists [19, 20]. Such diversity indicates that environmental changes and fragmentation may be barriers to dispersal of some dung beetle species [19, 21]. The community structure of dung beetles is strongly influenced by reproductive competition [22] over patchy and ephemeral food resources [23]. The high inter- and intraspecific competition coupled with random distribution and ephemerality of food suggest that dung beetles are probably good dispersers [24]. Studies on dispersal of Scarabaeinae dung beetles are few [2530], however some authors suggest that there may be differences in dispersal ability among species, or among individuals within a species due to different interspecific and intraspecific species traits [26, 29, 31]. For example, male Canthon cyanellus cyanellus LeConte, 1859 were found to have a faster movement rate than females, and young-mature individuals moved more often than immature or old individuals in a Mexican dung beetle assemblage [29]. A diurnal large-bodied species, Oxysternon conspicillatum (Weber, 1801), was recaptured two days after release 1 km away in an Ecuadorian rain forest [26], a longer distance than that traveled by small-bodied species of Onthophagus Latreille, 1807 and Canthon Hoffmannsegg, 1817. Therefore, an understanding of the relative abilities of species to move within and between ecosystems may aid our understanding of how Scarabaeinae communities are structured both locally and regionally. An important issue in the study of dung beetles is the lack of a standardized sampling protocol [32]. The sample design and the distance between traps indicted for sampling dung beetles vary widely, making it difficult to compare diversity patterns or community responses between studies. For instance, the movement of Canthon acutus Harold, 1868 was investigated in a mark-recapture experiment in which the authors observed that 95% of recaptured individuals were found within 26.2 m from traps [28]. These authors suggested tha (...truncated)