Trophic rewilding is the introduction of species to restore top–down trophic interactions and associated trophic cascades to promote self‐regulating biodiverse ecosystems. A core example of trophic rewilding is the restoration of large mammalian grazer communities to restore or maintain biodiverse open to half‐open landscapes. Across Europe, cattle and horse breeds are being introduced as substitutes of the extinct aurochs (Bos primigenius) and tarpan (Equus ferus). More recently, European bison (Bison bonasus) is being introduced because it is supposed to fill a niche that pure grazers such as cattle and horses leave empty, especially in terms of reducing woody encroachment. But how functionally diverse are the diets of these three species? We investigated this question in the Kraansvlak pilot; a trophic rewilding project in the Netherlands where European bison, horses, and cattle have been introduced in spatially heterogeneous landscapes of forest, shrub land, and grassland. We present 4 years of data from direct observations on the diet use of all three species. Whereas cattle and bison included a significant proportion of woody plants in their diet throughout the year, horses strictly grazed. However, cattle and bison differed clearly in terms of the woody plant part they used (bark vs. twigs), and we discuss how this may affect the way they influence vegetation structure. Finally, we discuss the implications of our study for the increasing number of trophic rewilding initiatives in Europe.
Pellet counts are widely used to monitor ungulates but rely on the assumption that pellets of different species are correctly identified in the field. Recent studies question this assumption using DNA barcoding techniques to check field identification rates. For Europe, which is undergoing a rapid shift towards more diverse ungulate assemblages, such an assessment is still missing. Using DNA barcoding on 3889 fecal samples from nine ungulate species in four European countries, we found average field misidentification rates varied from 0.6% for horse (Equus ferus) to 41.1% for roe deer (Capreolus capreolus). Most identification errors occurred between similar-sized species from the same taxonomic family. For a subset of samples from Sweden, we looked at the effect of dung morphometry, observer experience, and season on species identification success. Dung morphometry clearly distinguished moose (Alces alces) but not red (Cervus elaphus), roe, and fallow deer (Dama dama). Experienced observers performed better than novices for red and fallow deer although still making significant identification errors (26% and 17% incorrectly identified). Identification success was higher during spring and winter (x = 86%) than summer and autumn (x = 74%). We question pellet counts as an accurate monitoring tool where similar-sized species coexist and monitoring relates to the whole community. For this increasingly common situation across Europe, DNA testing or camera traps may be a better alternative. Pellet counts remain useful where only few species with clearly different dung morphology coexist (e.g., moose and roe deer) or when focused on species with distinctive dung morphology (e.g., moose).
The structure of the vanadium bromoperoxidase from the red algae Corallina pilulifera has been solved in the presence of the substrates, phenol red and phloroglucinol. The results obtained give a putative location close to the active site of the enzyme. In addition bromide has been soaked into the crystals and has been shown to bind unambiguously within the active site using single anomalous dispersion. A mutant of the enzyme where arginine 397 has been changed to tryptophan, shows a different behaviour on bromide binding regarding the displacement of a specific leucine amino acid which is seen to move towards the incoming ion in the wild-type protein to produce a hydrophobic environment within the active site.These results have increased our understanding of the mechanism of the vanadium bromoperoxidases and have demonstrated that the substrate and bromide are specifically bound to the enzyme active site.3
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.