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Grazing research should consider mobility and governance

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Pablo Manzano at BC3-Basque Centre for Climate Change
Pablo Manzano
Francisco Martín Azcárate at Autonomous University of Madrid
Francisco Martín Azcárate
Slimane Bencherif at Ziane Achour University of Djelfa
Slimane Bencherif
Daniel Burgas at University of Jyväskylä
Daniel Burgas
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Abstract

Maestre et al. (Reports, 24 November 2022, p. 915) analyze livestock grazing in global drylands without adequately considering critical ecological, social, and economic variables. Their analysis ignores mobile pastoralism practices and land governance arrangements, critical for sustainable grazing in dry rangelands.
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Grazing and ecosystem service delivery in global drylands | Science
https://www.science.org/doi/10.1126/science.abq4062
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269 S. Chatterjee, B. Price, Regression Analysis by Example (Wiley, ed. 2, 1991).
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MAR. 27, 2023
Grazing research should consider mobility and governance
PABLO MANZANO Basque Centre for Climate Change - BC3, Bilbao, Spain
FRANCISCO M. AZCÁRATE Autonomous University of Madrid, Spain
SLIMANE BENCHERIF University of Djelfa, Algeria
DANIEL BURGAS University of Jyväskylä, Finland
BAYARMAA BYAMBAA Technical University of Munich; Germany
MAR CABEZA University of Helsinki, Finland
LUIS CADAHÍA University of Oslo, Norway & University of Extremadura, Spain.
DAWN CHATTY University of Oxford, UK
JUSSI T. ERONEN University of Helsinki, Finland
KATHLEEN A. GALVIN Colorado State University, Fort Collins, USA.
PEDRO M. HERRERA Fundación Entretantos, Valladolid, Spain
ØYSTEIN HOLAND Norwegian University of Life Sciences, Ås, Norway
MOUSTAPHA A. ITANI University of Helsinki, Finland
MARYAM NIAMIR-FULLER Retired-Director of UNEP GEF, Purcellville, VA, USA.
FERRAN PAUNÉ University of Vic, Spain.
GREGORY K. PERRIER Northern Virginia Community College; Manassas, VA, USA
IAN SCOONES University of Sussex, Brighton, UK.
OULA SEITSONEN Lakehead University, Thunder Bay, ON, Canada & University of Oulu, Finland
NILS CHR. STENSETH University of Oslo, Norway
ELSA VARELA University of Göttingen, Germany
ANN WATERS-BAYER German Institute for Tropical and Subtropical Agriculture (DITSL), Witzenhausen, Germany
Maestre et al. (1) analyse the effect of livestock grazing on drylands at the global scale, contrasting low, medium,
and high levels of grazing pressure. Their effort in putting together an extensive collection of sampling points in
many of the world’s grazing ecosystems, and measuring multiple environmental variables is commendable, with a
very detailed capture of environmental services. However, the study suffers from an excessively simplied under-
standing of livestock-husbandry practices in the drylands, leading to inappropriate assumptions and misleading
conclusions.
We suggest that the claimed negative effects of high grazing pressure on ecosystem services in dry rangelands are
misleading because the study i) fails to include pastoralist mobility as a grazing management factor, and therefore
follows the error of many who do not differentiate between livestock systems (2); ii) does not consider how do-
mestic livestock mobility can enhance ecosystem services, including the conservation of wild herbivores; and iii)
excludes consideration of rangeland governance systems centred on livestock mobility that can improve both pro-
ductivity and ecosystem services – including biodiversity – in variable dryland ecosystems.
Mobility is a core strategy that both domestic and wild herbivores use to respond to environmental variability, but
this factor is excluded from the study by Maestre et al. (1), in which only xed plots with assumed constant graz-
ing pressure are assessed. In sedentary livestock systems, productivity (3), climate change mitigation (4), tree re-
generation (5), and genetic health of plant populations (6) underperform compared to mobile livestock systems in
the same environment. This is particularly critical in dryland systems, where reduced net primary productivity
translates into slower recovery from continuous disturbances and where mobility is a crucial element for the sus-
tainable and efcient use of natural resources (3, 4, 7). Mobility is a key factor for the ecological functionality of
wild herbivore systems (8) and for the prevention of land degradation (9). Migratory use of the drylands can ac-
commodate a large biomass of both domestic and wild herbivores (10).
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Grazing and ecosystem service delivery in global drylands | Science
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Maestre et al. (1) observe a correlation between low wild herbivore diversity and higher grazing pressure in drier
areas. This may, however, not reect causality but rather the need for wild herbivores to migrate seasonally away
from drier areas, or may reect poor governance of rangelands that impedes domestic or wild herbivore migration
in the areas that need it most. This may include undermining management of common resources and setting up
fences that prevent mobility through the landscape (11). While pastoralists can cope with such changes through
fodder provision if economic resources are available, this comes at a cost in terms of land degradation caused by
animal concentrations (12). This may be the effect measured by Maestre et al. (1) at some sites.
Pastoral systems are prime examples of socio-ecological systems (SES) where human communities are tightly cou-
pled with the local ecology, and have reciprocal feedbacks loops. They have developed in an intimate relationship
with their surroundings throughout their long history (13). While Maestre et al. (1) provide a good overview of the
grazing ecosystems, their viewpoint is mainly on the ecology and on the biotic/abiotic factors, and how these af-
fect the services provided from the ecosystem.Their viewpoint would gain much from deeper integration of the
human component, such as through the SES lens. It includes the modes of governance (both traditional and that
implemented by modern nation states), mobility, and stewardship by the drylands’ pastoral communities.
Effective governance is important for the quality of rangeland management (14). Different modes of governance
have major repercussions for ecosystem services through overuse of certain land areas, number of animals, and
the cascades that affect the biotic systems as a whole – and also interact with the abiotic environment.
Constraints on mobility in pastoral systems in dry rangelands can result in land degradation (15). Traditional pas-
toralist knowledge is holistic, but modern governance and also research have often overlooked it and its complex-
ity, triggering crises in pastoralism and land use caused by poorly thought-through policies (2, 13). But if mobile
systems are supported by appropriate policy and governance arrangements – which are measurable by specic in-
dicators (13) – then pastoralists’ productive and sustainable use of heterogeneous drylands would become evident.
The results reported in Maestre et al. (1) may therefore reect inappropriate policy and governance regimes in
dryland areas that limit mobility, rather than the inherent consequence of grazing, and may lead to inappropriate
policies for areas grazed by pastoralists’ livestock (2, 13) if such factors are not considered. We need more holistic
understanding of dryland ecosystems.
1. Maestre et al., Grazing and ecosystem service delivery in global drylands. Science 378, 915-920 (2022). doi
10.1126/science.abq4062
2. I. Johnsen, M. Niamir-Fuller, A. Bensada, A. Waters-Bayer, A Case of Benign Neglect: Knowledge Gaps about
Sustainability in Pastoralism and Rangelands (UNEP & GRID-Arendal, 2019).
3. Scoones, "New directions in pastoral development in Africa" in Living with Uncertainty: New Directions in
Pastoral Development in Africa (Intermediate Technology Publications, 1995), pp. 1–36.
4. Pardo, R. Casas, A. del Prado, P. Manzano, Carbon footprint of transhumant sheep farms: accounting for nat-
ural baseline emissions in Mediterranean systems. ResearchSquare 1838904 [Preprint] (2022).
https://doi.org/10.21203/rs.3.rs-1838904/v1.
5. P. Carmona, F. M. Azcárate, E. Oteros-Rozas, J. A. González, B. Peco, Assessing the effects of seasonal grazing
on holm oak regeneration: implications for the conservation of Mediterranean dehesas. Biol. Cons. 159, 240-
247 (2013). doi:10.1016/j.biocon.2012.11.015
6. García-Fernández et al., Herbivore corridors sustain genetic footprint in plant populations: a case for
Spanish drove roads. PeerJ 7, e7311 (2019). doi:10.7717/peerj.7311
7. Krätli, N. Schareika, Living off uncertainty: the intelligent animal production of dryland pastoralists. Eur. J.
Dev. Res. 22, 605-622 (2010). doi:10.1057/ejdr.2010.41
8. A. Kristensen, J.-C. Svenning, K. Georgiou, Y. Malhi, Can large herbivores enhance ecosystem carbon persis-
tence? Trends Ecol. Evol. 37, 117–128 (2022). doi:10.1016/j.tree.2021.09.006
9. F. Starrs, Transhumance as Antidote for Modern Sedentary Stock Raising. Rangel. Ecol. Manag. 71, 592-602
(2018). doi:10.1016/j.rama.2018.04.011
10. Nandintsetseg et al., Variability in nomadism: environmental gradients modulate the movement behaviors
of dryland ungulates. Ecosphere 10, e02924 (2019). doi: 10.1002/ECS2.2924
11. Y. Said et al., Effects of extreme land fragmentation on wildlife and livestock population abundance and dis-
tribution. J. Nat. Conserv. 34, 151-164 (2016). doi:10.1016/j.jnc.2016.10.005
12. Bencherif, P. Manzano, in Proceedings of the Joint XXIV International Grassland and XI International
Rangeland Virtual Congress Kenya 2021 (KALRO, 2022), pp. 917–920.
13. Manzano et al., Toward a holistic understanding of pastoralism. One Earth 4, 651–665 (2021).
doi:10.1016/j.oneear.2021.04.012
14. M. Herrera, J. Davies, P. Manzano Baena, Eds, The governance of rangelands: collective action for sustainable
pastoralism (Routledge, 2014).
15. FAO, Making way: developing national legal and policy frameworks for pastoral mobility (FAO, 2022).
MAR. 28, 2023
Grazing pressure, rather than management practice, is key to interpret our results: A response to
Manzano et al.
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Maestre et al. (1) observe a correlation between low wild herbivore diversity and higher grazing pressure in drier
areas. This may, however, not reflect causality but rather the need for wild herbivores to migrate seasonally away
from drier areas, or may reflect poor governance of rangelands that impedes domestic or wild herbivore migration
... For instance, while closed-canopy forests were seen for the last two centuries as the desirable natural ecosystem for most continental areas, it is now considered that alternative nonforested ecosystem states with continuous disturbances such as herbivores would have been the rule and not the exception in biomes where the productivity threshold is below what allows the establishment of rainforests (Bond, 2019;Pausas and Bond, 2020). Domestic herbivores that comply with characteristics such as mobile grazing (Manzano et al., 2023a) can therefore play an important role for ecosystem maintenance, and their disappearance lead to ecosystem deterioration. ...
... The importance of herbivory and megaherbivores is increasingly been acknowledged (Malhi et al., 2022;Pringle et al., 2023;Schmitz et al., 2023) along with the ecological relevance of the open ecosystems they have contributed to maintain, and which should not be lost for afforestations (Bond, 2016;Veldman et al., 2019;Nuñez et al., 2021;Stevens and Bond, 2024). While not that prevalent in the debate, it is known that their role can be fulfilled by grazing livestock if adequate management is provided, notably through adapted governance and through herbivore mobility (Manzano et al., 2023a), especially if considering the large wild herbivore densities that are natural in such settings (Manzano et al., 2023c;Pedersen et al., 2023). Maybe the best example is East African rangelands, where pastoralist milk economies have outcompeted crop farming thanks to a small time gap between dry seasons (Griffith et al., 2020) and have hence managed to maintain a rich wild herbivore fauna (Schieltz and Rubenstein, 2016). ...
... Regenerative land uses are known to achieve positive outcomes in terms of biodiversity and carbon stockage (Thompson et al., 2023;Maree et al., 2025 in this issue). On the other hand, grazing is known to bring higher diversity, ecosystem function and carbon storage in higher productivity pastures, but to cause problems in low-productivity ones, at least if only sedentary grazing systems are considered (Maestre et al., 2022;Manzano et al., 2023a, Ren et al., 2024. ...
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... However, with rising livestock numbers in combination with fodder provision, there is concern over pasture degradation, as high grazing intensity is known to lower plant species diversity, biomass and vegetation cover (Menezes et al., 2020;Munkhzul et al., 2021), alter soil parameters (Abdalla et al., 2018;Zhang et al., 2022), and lead to soil erosion (Dong et al., 2022). In addition, decreasing livestock herd mobility and changes in pastoral management practices further threaten rangeland health (Fernández-Giménez et al., 2018;Manzano et al., 2020Manzano et al., , 2022. ...
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Nomadic pastoralism is still practiced by around one-third of the Mongolian population. Recent socio-economic constraints have challenged pastoral livelihoods and rising livestock numbers threaten overall rangeland health and biodiversity conservation. In the Mongolian Gobi, herder households fully depend on livestock production but little is known about their livelihood trends and potential compatibility with protected area goals. We combined interview data in the Great Gobi B strictly protected area (SPA) with secondary data on regional and national herder households to determine the importance of social networks, willingness to continue a herding lifestyle, and degree of involvement in protected area (PA) management. Our descriptive data confirm that herding is no longer centred on a subsistence lifestyle but rather around cashmere production. Contrary to sustainability goals, especially in protected areas, herder households continue to increase livestock numbers in response to high expenditures in the economic reality of a market economy. We conclude that herders in the Great Gobi B SPA are reaching neither socio-economically nor ecologically sustainable livestock numbers which challenge herders’ livelihoods and PA management alike. We recommend enhancing communication between the PA management and the herding community and increasing participatory conservation activities. National strategies are needed to resolve the current dilemma of increasing livestock numbers to meet livelihood demands and the growing threat to rangeland health.
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Traditional herders' perception of job satisfaction and integration into society: Another obstacle to the survival of pastoralism?
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A CLASSIFICATION OF PASTORALISM IN SPAIN: UNDERSTANDING THE PAST TO ADDRESS PRESENT CHALLENGES
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After centuries as a flagship economic activity, pastoralism in Spain is today in danger of collapse due to the simultaneous processes of abandonment and industrialisation. With a consensus on the need to revert this decline, a characterisation of pastoralism is needed in the design of an efficient framework for action. Through a participatory process with experts, we carried out this characterisation of Spanish pastoralism, identifying the most representative systems and communities. We studied the causes and consequences of pastoral evolution over the last 250 years, explained by biophysical, technological, governance and social parameters. We achieved a harmonised classification of eleven pastoral systems, classified into four groups with mobility parameters (large migratory systems, short-distance transterminance, daily mobile grazing and semi-wilderness). Large mobility systems were subdivided into ten pastoral communities, characterised by strong sociocultural ties beneath farm management. The consideration of pastoral systems and communities in policy can orient effective rural development, while optimising the allocation of resources for environmental conservation and climate neutrality. This article was published open access under a CC BY-NC 4.0 licence: https://creativecommons.org/licenses/by-nc/4.0/ .
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Dryland sensitivity to climate change and variability using nonlinear dynamics
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Primary productivity response to climatic drivers varies temporally, indicating state-dependent interactions between climate and productivity. Previous studies primarily employed equation-based approaches to clarify this relationship, ignoring the state-dependent nature of ecological dynamics. Here, using 40 y of climate and productivity data from 48 grassland sites across Mongolia, we applied an equation-free, nonlinear time-series analysis to reveal sensitivity patterns of productivity to climate change and variability and clarify underlying mechanisms. We showed that productivity responded positively to annual precipitation in mesic regions but negatively in arid regions, with the opposite pattern observed for annual mean temperature. Furthermore, productivity responded negatively to decreasing annual aridity that integrated precipitation and temperature across Mongolia. Productivity responded negatively to interannual variability in precipitation and aridity in mesic regions but positively in arid regions. Overall, interannual temperature variability enhanced productivity. These response patterns are largely unrecognized; however, two mechanisms are inferable. First, time-delayed climate effects modify annual productivity responses to annual climate conditions. Notably, our results suggest that the sensitivity of annual productivity to increasing annual precipitation and decreasing annual aridity can even be negative when the negative time-delayed effects of annual precipitation and aridity on productivity prevail across time. Second, the proportion of plant species resistant to water and temperature stresses at a site determines the sensitivity of productivity to climate variability. Thus, we highlight the importance of nonlinear, state-dependent sensitivity of productivity to climate change and variability, accurately forecasting potential biosphere feedback to the climate system.
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Carbon footprint of transhumant sheep farms: accounting for natural baseline emissions in Mediterranean systems
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Effects of extreme land fragmentation on wildlife and livestock population abundance and distribution
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  • Oct 2016
  • J NAT CONSERV
Fragmentation, degradation and loss of natural habitats are now recognised as major threats to wildlife conservation and mobile pastoralism in East African savannas. These processes are driven primarily by land tenure and policy, increasing human population, expansion of settlements and agricultural farms, road networks, urban development and fencing. To understand and characterise the forces driving habitat fragmentation, we analyse how biophysical (soils, slope, rainfall, rivers) and human-created (roads, towns, parks, quarries) features influence where people choose to fence the land in the Athi-Kaputiei ecosystem of Kenya. We also explore the consequences of land fragmentation through fencing on the abundance and distribution of wildlife and livestock populations. We show that fences are most highly concentrated along the major roads and around the major urban centres. Movements of migratory wildebeest and zebra between the Nairobi National Park and the pastoral Kitengela Plains adjoining the park on the south are getting increasingly impeded by increasing concentration of fences. Populations of wildebeest and other herbivores have collapsed to a small fraction of their former abundance largely owing to destruction of their habitats and obstruction of their movements between the park and the pastoral lands by fences and other land use developments. Conserving the key seasonal wildlife dispersal areas in the Athi-Kaputiei Plains is critical to ensuring the future viability of several key wildlife species in Nairobi National Park. Several initiatives, including a conservation land lease program has been launched, but their spatial coverage and funding levels would need to be greatly expanded to secure sufficient open spaces for both wildlife and livestock.
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Assessing the effects of seasonal grazing on holm oak regeneration: Implications for the conservation of Mediterranean dehesas
Article
  • Mar 2013
  • BIOL CONSERV
Scattered trees in agricultural landscapes are globally declining due to the intensification of agricultural practices. Dehesas, highly species-diverse Mediterranean open woodlands, are seriously affected by this decline, because of a generalized regeneration failure of oak, which compromise their long-term stability. Traditionally, dehesas were the wintering areas for transhumant herds, but transhumance is disappearing in the Mediterranean, due to multiple causes. Reductions in grazing intensity or grazing abandonment have been proposed to improve oak regeneration in dehesas, but the effect of the recovery of noncontinuous grazing practices such as transhumance has not been tested to date. We measured different indicators of holm oak regeneration and condition in dehesas under transhumant grazing and in dehesas under permanent grazing in southern Spain. Oak juveniles were remarkably less browsed and their canopies covered a much higher area in transhumant estates. As a consequence, the median density of saplings was more than four times higher in transhumant than in permanently-grazed estates. Although transhumant grazing is necessarily associated with a reduction in the stocking rate across the year, the timing of grazing was always included as a predictor in the best models to explain the condition and density of holm oak. Our results suggest that the lack of oak regeneration in dehesas can be caused not only by the increases in stocking rates, but also by the recent abandonment of traditional grazing practices like transhumance. We propose the recovery of seasonal grazing regimes based on transhumant pastoralism as a measure to improve the conservation status of dehesas.
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