EUROPEAN JOURNAL OF ENTOMOLOGY

Eur. J. Entomol. 110 (1): 81-86, 2013 | DOI: 10.14411/eje.2013.010

Influence of linear versus network corridors on the movement and dispersal of the bush-cricket Metrioptera roeseli (Orthoptera: Tettigoniidae) in an experimental landscape

Anders ERIKSSON, Matthew LOW, Åsa BERGGREN^*

Department of Ecology, PO Box 7044, Swedish University of Agricultural Sciences, SE-75007 Uppsala, Sweden; e-mails: asa.berggren@slu.se; anders.eriksson@speedmail.se; matt.low@slu.se

^* Corresponding author.

Linear landscape elements are generally considered beneficial for promoting the movements of species between isolated habitats. However, relatively little consideration has been given to the effect of interconnections (nodes) between these elements: e.g. a simple linear element offers limited options for movement, whereas a network of such structures provides an exponential increase in potential pathways. In this pilot study we compared two experimental landscapes (single versus a lattice of four interconnected linear elements) in terms of their effect on the movement of males of Roesel's bush-cricket (Metrioptera roeseli) (Orthoptera: Tettigoniidae). Emigration of released bush-crickets from experimental landscapes was greater if there was a single rather than a lattice of linear elements (corridors). In the landscape with a lattice of corridors, 50% of the bush-crickets changed their direction of movement at nodes at least once. There was also evidence that nodes were attractive to bush-crickets; a higher proportion of individuals were found in and around nodes than in adjoining corridors, with the strength of this effect (i.e. aggregation at nodes) increasing with time. Thus nodes may not only affect the direction of movement but may also act as a local attractant. These effects may have an important role in the movement of species and their success in colonizing fragmented landscapes. These results indicate that in future landscape planning more consideration should be given to the connectivity between linear landscape elements as it is likely to be important in determining the movement and distribution of species.

Keywords: Tettigoniidae, Metrioptera roeselii, movement, corridor, nodes, intersections, cross-roads, linear elements

Received: August 2, 2011; Revised: July 2, 2012; Accepted: July 2, 2012; Published: January 2, 2013  Show citation