On the Search for Grazing Personalities: From Individual to Collective Behaviors

Abstract

While grazing lands can offer a diverse range of forages, individuals within herds prefer to graze some habitats and not others. They can have consistent differences in grazing patterns and occupy specific spatial domains, whilst developing tactics and strategies for foraging that are specific to their grazing personalities. In this review, we explore the development of our understanding of grazing personalities, as we move away from the search for an "optimal animal" toward designing behavior-customized herds with an arrangement of individual grazing personalities that enhance ecosystem services and productivity. We present a "grazing personality model" that accounts for the personality of individual animals and for collective behaviors of herds. We argue that grazing personalities of grazing ruminants and other large herbivores are in part genetically determined, and that they can act at the individual and collective level. The social and biophysical environments as well as the emotional state of animals regulate the expression of "grazing genes" that are observed phenotypically as distinct grazing personalities. The reproductive and sexual successes of individuals and herds filter for allele variants of grazing genes and in turn determines their relative frequency. While the selection of one grazing personality may be adequate for homogeneous pastoral systems, the design of herds with a range of grazing personalities that are matched to the habitat diversity may be a better approach to improving the distribution of grazing animals, enhancing ecosystem services, and maximizing productivity.

Grazing Allometry: Anatomy, Movement, and Foraging Behavior of Three Cattle Breeds of Different Productivity

“…Generally, cattle do not cover available space evenly, especially on heterogeneous alpine pastures ( 10 , 23 , 48 ). It seems logical that animals that walk less visit fewer parts of the pasture and leave most places undiscovered.…”

“…Original Braunvieh cattle took an intermediate position, but were much more similar to Angus × Holstein than to Highland cattle. Differences in the quality of the selected forage may be additionally explained by cattle's physical access to steep slopes ( 10 ), which typically offer forage of lower quality. While large body mass may hinder high-productive breeds' ability to visit steep areas, Highland cattle can reach them and forage the poorer forage there.…”

“…Although it is tempting to modify breeding aims toward higher output, our data suggest that if Highland cattle were bred more productively, many of these benefits would be lost, as has been the case with other breeds. On the other hand, breeders of high-productive cattle may consider differences among individuals as a potential to increase production efficiency ( 9 , 10 ).…”

“…In addition to these prioritized traits, which breeding controls, there are numerous characteristics that are not accounted for in selection and have co-evolved unnoticed. Some of these hidden traits recently have gained awareness, such as robustness ( 8 ), longevity, and feed efficiency ( 9 ), while others, such as claw size, movement, and foraging behavior, have long been ignored in herdbook breeding ( 10 ).…”

Researching Human-Cattle Interaction on Rangelands: Challenges and Potential Solutions

“…There is immense value in studying human-animal interactions in rangeland cattle because they can provide insight for animal welfare and production [ 3 , 11 ], as well as how individual differences in behavior manifest in altering landscapes and biodiversity of surrounding ecosystems [ 133 , 134 , 135 , 136 ]. However, this value is at risk of being undermined by methods that do not take into account the unique characteristics of range cattle outlined above.…”