Adrian M. Shrader
Mammal Research Institute
Forage (honey bee)DemographyForagingHabitatPredationEcologyHerdGeographyGrasslandGrazingVigilance (behavioural ecology)Ceratotherium simumHerbivoreWet seasonWhite (horse)BiologyZoologyCompetition (biology)PredatorDry season
81Publications
17H-index
926Citations
Publications 61
Newest
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#1Adrian M. Shrader (Mammal Research Institute)H-Index: 17
#2Ina Louw (University of Pretoria)H-Index: 4
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(2020). Conservation Biology in Sub-Saharan Africa. African Journal of Range & Forage Science. Ahead of Print.
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#1Anita van Deventer (Mammal Research Institute)
#2Adrian M. Shrader (Mammal Research Institute)H-Index: 17
Vigilance is just one of the many fitness-enhancing activities that animals do each day. However, as vigilance is used for both predator detection and obtaining social information, individuals must decide how to divide their time between these two vigilance types. Yet, it is unclear (1) how prey species living in the centre and edge of groups prioritize their use of these different vigilance types and (2) how this prioritization varies with increasing risk. To explore this, we focused on the deg...
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#1Melissa H. Schmitt (UKZN: University of KwaZulu-Natal)H-Index: 6
#2Adrian M. Shrader (UKZN: University of KwaZulu-Natal)H-Index: 17
Last. David Ward (UKZN: University of KwaZulu-Natal)H-Index: 43
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Megaherbivores have been of particular interest to scientists because of the physiological and ecological challenges associated with their extreme body size. Yet, one question that has seldom been explored is how browsing megaherbivores cope with plant secondary metabolites (PSMs), such as tannins, found in their food. It is possible that the sheer body size of these megaherbivores allows them to ingest tannins with no deleterious effects. However, it is plausible that megaherbivores must rely o...
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#1David Ward (KSU: Kent State University)H-Index: 43
#2Melissa H. Schmitt (UKZN: University of KwaZulu-Natal)H-Index: 6
Last. Adrian M. Shrader (UKZN: University of KwaZulu-Natal)H-Index: 17
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While feeding, mammalian browsers (primarily eat woody plants) encounter secondary metabolites such as tannins. Browsers may bind these tannins using salivary proteins, whereas mammalian grazers (primarily eat grasses that generally lack tannins) likely would not. Ruminant browsers rechew their food (ruminate) to increase the effectiveness of digestion, which may make them more effective at binding tannins than nonruminants. Few studies have included a sufficient number of species to consider po...
3 CitationsSource
#1Ivana Cinková (UKZN: University of KwaZulu-Natal)
#1Ivana Cinková (UKZN: University of KwaZulu-Natal)H-Index: 4
Last. Adrian M. Shrader (UKZN: University of KwaZulu-Natal)H-Index: 17
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Eavesdropping on vocal signals allows animals to gather information about conspecifics. For males, eavesdropping can be a low-risk method for determining the dominance status (e.g. territorial or subordinate) and motivation (e.g. mate seeking) of rivals. Adult southern white rhino males, Ceratotherium simum, are territorial and, in addition to other vocalizations, use contact and courtship calls when communicating with females. Although male territories are exclusive, the owners may tolerate up ...
2 CitationsSource
#1Keenan Stears (UKZN: University of KwaZulu-Natal)H-Index: 6
#2Adrian M. Shrader (UKZN: University of KwaZulu-Natal)H-Index: 17
Many studies on the coexistence of wildlife with livestock have focused primarily on similar-sized species. Furthermore, many of these studies have used dietary overlap as a measure of potential competition between interacting species and thus lack the important link between dietary overlap and any negative effects on a particular species-a prerequisite for competition. Consequently, the mechanisms that drive interspecific interactions between wildlife and cattle are frequently overlooked. To ad...
1 CitationsSource
For large mammals, area expansion is a key conservation measure to prevent species’ decline and extinction. Yet, its success depends on whether animals discover and later use these areas. Here, using GPS data, we investigated how herds of elephants detected and used an area made available to them after the removal of a fence. We studied the elephants’ behaviour before and after the fence removal, accounting for seasonal changes in movement patterns. In contrast to previous studies, herds visited...
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#1Melissa H. Schmitt (UKZN: University of KwaZulu-Natal)
#1Melissa H. Schmitt (UKZN: University of KwaZulu-Natal)H-Index: 6
Last. Adrian M. Shrader (UKZN: University of KwaZulu-Natal)H-Index: 17
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Abstract Tannins are a key chemical defense that plants use against mammalian herbivores. To cope with tannins, many herbivores have evolved salivary tannin-binding proteins that precipitate tannins in forage items, and thus minimize their deleterious effects. In the past, one specific type of salivary tannin-binding protein was identified (proline-rich proteins), and has been found in a range of mammalian species. However, there are other proteins in the saliva of mammalian herbivores that also...
6 CitationsSource