High fodder value and feeding likelihood favour endozoochorous plant dispersal

Abstract

Questions In pasture‐dominated landscapes, endozoochory by large herbivores is an important vector of plant dispersal. Conditions influencing the potential for endozoochorous dispersal of plant species by grazers are, however, still poorly known. Here, we assess the impact of feeding habits and functional traits on the likelihood of endozoochorous dispersal by cattle (ruminants) and horses (non‐ruminants). Location Pasture of 27 ha in NW Germany, year‐round grazed by free‐ranging cattle and horses. Methods Vegetation relevés were established in 45 plots, from which dung samples of cattle and horses were collected. The number and composition of seedlings emerging from dung samples were compared with the vegetation of the study site in terms of plant functional trait composition. For the first time, feeding habits were included in the analysis. GLMs were used to identify traits that increased the potential for endozoochorous dispersal. Results A total of 65 species germinated from the dung samples. These species had higher average fodder and nutrient indicator values than the species composition of the vegetation. In particular, species found in horse dung were more tolerant of grazing and had more elongated seeds. The likelihood of endozoochorous dispersal was higher for common than for rare species and was influenced by feeding habits. Conclusions The likelihood of plant species being dispersed endozoochorously can be linked to different functional traits and is dependent on the type of grazer and the population size of target species in the vegetation. Differences between cattle and horses in seed dispersal may result from species‐specific grazing habits and different digestion modes.

Effects of mowing, grazing and fertilization on soil seed banks in temperate grasslands in Central Europe

“…Missing effects of grazing on the seedling density might be due to described positive effects being counteracted by negative effects of grazing before and during seed set, as found by Sternberg et al (2003). Nevertheless, a certain proportion of seeds eaten by livestock is still able to germinate after excretion and may also become part of the seed bank (Gilhaus et al, 2017b).…”

Human-Mediated Dispersal and the Rewiring of Spatial Networks

“…On en es used for transport On en es moved by humans Organisms moved by humans Small with appendages, hairy, clinging seeds [32,84] persistent seed bank [84] Light, flat seeds [16], appendages numerous seeds, persistent seeds [84] short-lived annuals, pioneer species Small seeds, numerous seeds, high nutrient values, common species, elongated seeds [91] Hor culture: aesthe c, decora ve, ornamental, novel [89] Agriculture: increased fruit size [8], [85], parasites with capacity to switch hosts [86] ectoparasites with appendages, resistant life stages, invertebrate propagules [87] Resistant life stages, invertebrate propagules [20,54], asexual reproduc on, diapause capacity, low metabolism, small, abundant, na ve [88] On humans Game animals: medium size, sedentary, non-migratory, cura ve, aphrodisiac [90] Pet animals: colourful, small-medium-sized, exo c, rare, ease of transport [90] Transloca on: useful to humans [16] threatened species, small popula on size, charisma c Small, abundant, na ve [ Increasing exposure to human contact increases the likelihood of human-vectored dispersal Human dispersal vectors affec ng dispersal speed distances Animal and plant traits that enable human-vectored dispersal kernels (Box 1). Such dispersal might best be described by gravity models, which can capture how human movement patterns reflect not only distance, but also changed patterns caused by travel between 'attractive' nodes, such as cities [27].…”

“…(C) Examples of plant (green) and animal (blue) traits that enable dispersal by humans and associated entities, categorised either as accidental or intentional dispersal. Example references[8,16,20,23,24,32,54,55,[83][84][85][86][87][88][89][90][91].…”

Complementing endozoochorous seed dispersal patterns by donkeys and goats in a semi-natural island ecosystem

“…In addition, the type of digestive system might explain differences in the seed dispersal patterns between donkeys (hindgut fermenters) and goats (ruminants). Dispersal through endozoochory on one hand is affected by the survival of the seeds in the digestive tract [ 62 ] and on the other hand by the feeding habits [ 63 ]. The resulting dispersal spectrum from our experiment reflects the feeding habits of donkeys and goats.…”