Responses of predatory invertebrates to seeding density and plant species richness in experimental tallgrass prairie restorations

Abstract

a b s t r a c tIn recent decades, agricultural producers and non-governmental organizations have restored thousands of hectares of former cropland in the central United States with native grasses and forbs. However, the ability of these grassland restorations to attract predatory invertebrates has not been well documented, even though predators provide an important ecosystem service to agricultural producers by naturally regulating herbivores. This study assessed the effects of plant richness and seeding density on the richness and abundance of surface-dwelling (ants, ground beetles, and spiders) and aboveground (ladybird beetles) predatory invertebrates. In the spring of 2006, twenty-four 55 m × 55 m-plots were planted to six replicates in each of four treatments: high richness (97 species typically planted by The Nature Conservancy), at low and high seeding densities, and low richness (15 species representing a typical Natural Resources Conservation Service Conservation Reserve Program mix, CP25), at low and high seeding densities. Ants, ground beetles, and spiders were sampled using pitfall traps and ladybird beetles were sampled using sweep netting in [2007][2008][2009]. The abundance of ants, ground beetles, and spiders showed no response to seed mix richness or seeding density but there was a significant positive effect of richness on ladybird beetle abundance. Seeding density had a significant positive effect on ground beetle and spider species richness and Shannon-Weaver diversity. These results may be related to differences in the plant species composition and relative amount of grass basal cover among the treatments rather than richness.Published by Elsevier B.V.

Ant species assembly in constructed grasslands is structured at patch and landscape levels

“…Although ants are highly associated with dominant vegetation types (e.g. forests vs. grasslands), most studies have found little to no relationship with plant richness or cover within a given vegetation type (Hill et al, 2008;Nemec et al, 2014;Peters et al, 2016). Some studies have identified plant structure or vegetation height as a more important characteristic for predicting ants in grasslands (New, 2000;Debinski et al, 2011).…”

Spider community responses to grassland restoration: balancing trade‐offs between abundance and diversity

“…Yet, despite their importance and potential utility in monitoring and a heightened interest in restoration within the past few decades, little research has focused on the impact of grassland restoration on spider communities in North America (Sampson & Knopf ; Nemec et al ). While more work has been conducted in European systems (see Bell et al , for review), European grasslands and their management and restoration differ in significant ways from U.S. systems, especially those in the arid and semiarid West.…”

“…This study aims to describe not only the spider communities present in an arid grassland in the western United States, but also to examine habitat variables that influence spiders in these communities. Unlike other studies that have focused on invertebrate responses to grassland/shrub‐steppe restoration (e.g., Mortimer et al ; Longcore ; Déri et al ; Borchard et al ; Nemec et al ), we focused on spiders specifically to enhance our ability to pinpoint habitat variables underlying responses of different species of spiders to restoration. We assessed three treatments including native (or reference sites), degraded, and restored grassland habitat.…”

“…However, the majority of studies on grassland restoration have focused either on vegetation or vertebrate responses (e.g., Wisdom et al 2002;Knick et al 2003;Huddleston & Young 2004;Huddleston & Young 2005;Beck et al 2012), even though grassland invertebrates are highly diverse and provide important ecosystem services such as pollination, nutrient cycling, food for vertebrates, and pest control (Weisser & Siemann 2004;DeBano 2006;Kimoto et al 2012aKimoto et al , 2012bGonzalez et al 2013). Thus, it remains unclear how grassland restoration influences invertebrate diversity and function (Nemec et al 2014), particularly in North American grasslands.…”

Ground-Dwelling Arthropod Communities Related to Nesting Success of Northern Bobwhite at Two Western Oklahoma Wildlife Management Areas

“…A similar study in 2013 found that increased inflorescence and vegetative growth, often encouraged by rainfall or increased available water, encouraged predatory arthropods to stay in patches for longer periods of time (Nemec et al 2014).…”