High potential of sub-Mediterranean dry grasslands for sheep epizoochory

Abstract

There is a general decline of grasslands across Europe due to habitat loss and degradation. Ensuring plant dispersal thus becomes a key process for preserving grassland patches in all scales. We examined diaspore dispersal by sheep epizoochory in the pastures of the North Adriatic Karst (NW Slovenia) and determined the qualitative and quantitative features of diaspores in fur. We recorded 25,650 diaspores of 141 plant taxa (with 107 taxa and 23,350 diaspores determined to species level), using three different methods: (i) the "whole-coat method", (ii) the "part-of-thecoat method" and (iii) a "seedling emergence method". A comparison of these techniques revealed that the "wholecoat method" provided the highest number of diaspores and plant species. All diaspores were clustered into five emergent groups based on seven functional traits (diaspore weight, length, width, height, volume, specific weight and the diaspore surface structure). Our research revealed that sheep represent an important dispersal vector, since about half of the plant species recorded in the pastures were found as diaspores in fur. This study contributes to knowledge about the modes of seed dispersal in seminatural grasslands. Taking into account that livestock play a key role in vegetation dynamics, understanding their effects on seed dispersal is essential for conservation and restoration of these species-rich grassland communities.

Interactions between global change components drive plant species richness patterns within communities in mountain grasslands independently of topography

“…Sheep are a noticeable effective disperser through epi‐ and endozoochory, thanks mainly to their wool and their relatively less aggressive digestive process (Kaligarič, Brecl, & Škornik, ; Rosenthal, Schrautzer, & Eichberg, ). In addition, the plant species are carried by shepherds through a higher number of grassland patches and more varied plant communities (Sebastiá et al., 2008).…”

Biogeography of amphi-adriatic Gentianella crispata (Gentianaceae): a northern refugium and recent trans-adriatic migration

“…The low genetic differentiation of the Italian population, its average genetic diversity (see also Gargano et al 2009) and increased rarity value (Table 1) would be compatible with a more recent immigration. However, the probability for dispersal by natural means is low due to lacking morphological adaptations of the seeds, but dispersal of grassland species such as G. crispata is likely mediated via transhumance or human migration events (Poschlod and WallisDeVries 2002;Kaligarič et al 2016).…”

Zoochory on and off: A field experiment for trait‐based analysis of establishment success of grassland species

“…The above‐mentioned fact that seed dispersal usually peaks close to the mother plants, especially in the absence of dispersal vectors (Wilson, 1993; Nathan et al, 2008) explains our observation that most of the sown species and individuals were observed close to the source plots. The dispersal distance by epizoochory ranges from a few metres to several hundred kilometres (Mouissie et al, 2005; Manzano & Malo, 2006), dependent on the type of grazers, as seeds adhere to sheep's fur better and in higher numbers than to cattle, horses or donkeys (Mouissie et al, 2005; Couvreur et al, 2008; Kaligarič et al, 2016). Since our study sites were grazed by cattle, which have short and straight hair, the seed retention rates were most probably rather short (Couvreur et al, 2008).…”