Oviposition site selection of a threatened moth Eriogaster catax (Lepidoptera: Lasiocampidae) in agricultural landscape—implications for its conservation

Abstract

Shrubby field margins and hedgerows play an important role for many species of flora and fauna in agro-ecosystems, including those which are rare or endangered. A characteristic species of these semi-natural habitats in agricultural landscape is the Eastern eggar, Eriogaster catax (Linnaeus, 1758): a moth species threatened in many European countries. In this study we investigated the oviposition preferences of E. catax at host plant level in agricultural landscape in south-western Poland, near of the northern limit of the species distribution in Europe. In total we surveyed 796 host plants. Altogether we found 439 eggs batches or caterpillar webs of E. catax on 373 occupied plants. Most of them (92.3%) were on blackthorn Prunus spinosa, which was preferred host plant next to pear Pyrus spp. However, the most important predictor of the presence of egg batches were microclimatic conditions. We recorded that females preferred host plants exposed to direct sunlight and with south and west-facing slopes for oviposition and avoided those inside of the dense shrub canopy. Eggs were laid more often on the trunk and on the upper half of the host plant, however there was a significant difference in vertical and horizontal position of egg batches in relation to the position of the plant. Inside of the shrub canopy, eggs were laid in higher parts of host plant and closer to the trunk, than at the edge and on solitary plants. Based on our observations the management strategies for the habitats of the species are proposed and discussed.

Eriogaster catax (Linnaeus, 1758) (Lepidoptera: Lasiocampidae) – first record in Muntenia (southern Romania)

“…The nest was built at the intersection of several common hawthorn (Crataegus monogyna) branches, found at the edge of the clearing, outside the area with a dense canopy. This supports other observations made on the habitat preferences at this species (Kadej et al 2018). Occurring in bushy grasslands, coppice woodlands and hedgerows, E. catax is a species generally associated to agricultural landscapes with semi-natural shrubby vegetation and hedgerows.…”

Ground beetles (Carabidae) of field margin habitats

“…Studies on vegetation and accompanying entomofauna in field margin habitats help evaluate the role of these habitats as potential refugia for useful animals in Integrated Pest Management (IPM) and as components influencing ecological balance at the level of landscape (Barczak 1993;Barczak et al 2000;Ramsden et al 2015;Tscharntke et al 2016;Kadej et al 2018). Other important aspects are the species composition and changes in plant communities, as well as the age of these field margin ecosystems (Marshall and Moonen 2002;Gaigher et al 2016), and their structural diversity/layer structure (Taboada et al 2010).…”

“…In Poland, where about 61% of total area is covered by farmland, nearly half of the more than 2.5 million farms are still smaller than 2 ha, and the rural landscape is relatively rich in non-crop areas (Wuczyński et al 2011). However, in the last few years, these agricultural structures and related habitats have been severely threatened in Poland and other countries of Central and Eastern Europe, by abandonment, afforestation or agricultural intensification (Kadej et al 2018).…”

“…Intensive farming practices have significantly reduced the fragmentation/mosaic spaces of the agricultural landscape (Rusch et al 2016;Landis 2017;Kadej et al 2018;Ortiz-Martinez and Lavandero 2018). The monitoring of ecological/agroecological infrastructure in the cultural landscape is one of the aspects that should be considered in ecological engineering (Franin et al 2016;Ortiz-Martinez and Lavandero 2018).…”

Linking mesoscale landscape heterogeneity and biodiversity: gardens and tree cover significantly modify flower-visiting beetle communities

“…This may indicate a requirement for diverse resources associated with different life stages, such as dead branches for oviposition and larval development and more open sites with abundant nectar resources. Preferences for sunny sites (Kadej et al 2018) and shady or sheltered ones (Dover et al 1997) have both been observed in insects, though the response of beetles to small-scale habitat complexity varies (Ford et al 2017).…”