Foreword: Strategic Grazing Management for Complex Creative Systems

Abstract

The management of grazing on our rangelands is a complex task that most landholders undertake on the basis of their experience. Science has made many contributions to the understanding of grazing, but currently offers few recommendations on managing pastures other than generalities, such as that one should not 'overgraze'. The dilemma is that the landholder must balance the competing demands of the livestock and of the health of the pasture, which essentially represent trade-offs between the present and the future. The optimum strategy for any one time is difficult to discern, partly because of these long and short-term trade-offs, but also because of interactions with economic outcomes and sociological factors, and the confusing effect of rainfall variability. When variability is high the lessons learnt from last year, or the year before that, are unlikely to be applicable to the current year. With this combination of complexity and variability, it is perhaps not surprising that research on this topic has so far led to much knowledge about grazing management, but apparently little practical scientific advice. Nevertheless, I perceive that this might be about to change. Climate variability is now being accepted as a major driving force in rangeland management and explicitly addressed. And the complexity of the landscape, the production system, the ecosystem and people's economic overlay, is at least being encompassed, if not understood, through the power of the computer. The ability of the advanced decision support systems to combine information from a whole range of sources, such as land system maps, models of biological processes and expert experience, into aids to decision making, is indeed awesome. The recognition of the importance of social values in determining the best grazing system and that landholders themselves have an important part to play in developing best systems, is also a valuable advance in methodology. It is this new world of grazing management that has, in part, been captured in this special issue on grazing management. An Editor is limited in scope by the papers that are offered and by those that can be prepared within the deadlines imposed by publication. There were many more papers than those presented here that were outlined in abstract, but did not reach the deadline. It is hoped that the Journal will be able to publish some of these in future. Each will have its value, although not with the collective force arising from the synergy of the special issue.

Existing Accessible Modeling Tools Offer Limited Support to Evaluation of Impact Investment in Rangeland Ecosystem Services

“…In justifying grazing management interventions, the impact investment literature commonly cites holistic range management and the work of Allan Savory (Pons et al, 2013;Culp et al, 2015;Lang et al, 2017), who is arguably one of the most prominent advocates for rotational grazing. However, a variety of rotational systems exist, and the suggestion that some form of rotational grazing provides better economic and environmental returns has received considerable attention from the academic community since the 1930s (Morgan, 1933;Hodgson et al, 1934;Briske et al, 2008;Barnes and Hild, 2013). Specific rotational grazing approaches vary with respect to variables like stocking rate, stocking density, rotations per year, grazing days, and length of grazing deferment, and many land managers who have embraced various forms of rotational grazing management report seeing dramatic evidence of improved productivity and profitability [case studies in Rangelands 2013 special issue, 35 5].…”

“…The lack of rigorous experimental evidence substantiating these anecdotal claims creates challenges for those looking to predict the benefits of an investment in rotational grazing, or evaluate them ex-post. The ability to do at least one of these is likely to be necessary to secure investment and, depending on contract structure, to attribute returns in an impact investing context (Barnes and Hild, 2013). Yet, the existence of such a significant body of compelling evidence and individual rancher experience exists makes it difficult to conclude that the benefits of rotational grazing management are simply an illusion (Sayre, 2001;While, 2008;Teague et al, 2011;Barnes and Hild, 2013;Norton et al, 2013).…”

Virtual herding for flexible livestock management – a review

“…Stocking strategies, in which livestock are moved among paddocks based on fixed movement schedules, are the most inflexible (Barnes and Hild 2013) and should be avoided.…”

“…The spatial and temporal variability of soils, vegetation and climate, and foraging behaviour by livestock, are key influences on the ability to manage rangeland sustainability. Until recently, most of our understanding of the plant-animal interface has come from small research plot data (Ash and Stafford Smith 1996;Barnes and Hild 2013;Teague et al 2013). However, a proper understanding of free-ranging animal behaviour requires both small plot-and landscape-based data in which the interactions among plants (Soder et al 2007) and livestock (Estevez et al 2007) influence foraging behaviour at both these scales.…”

“…However, a proper understanding of free-ranging animal behaviour requires both small plot-and landscape-based data in which the interactions among plants (Soder et al 2007) and livestock (Estevez et al 2007) influence foraging behaviour at both these scales. Foraging behaviour is affected by both the physiology of animals (Provenza et al 2007;Finger et al 2014) in addition to many factors external to the animal (Anderson 2010) and both are significant when large numbers of physiologically diverse animals forage on large heterogeneous landscapes (Barnes and Hild 2013;Norton et al 2013). Therefore, scale is a key to our understanding of the plant-animal interface as it influences the behaviour of livestock.…”