Karoo Predator Project

Karoo Predator Project Management Survey

Industry Sector: Cattle and Small Stock

Research focus area: Predation management

Research Institute: University of Cape Town

Researcher: Beatrice Conradie

Title Initials Surname Highest Qualification
Robertson N Nattrass D Phil
Prof J Piesse PhD

Year of completion : 2018

Aims of the project

  • Conduct an extra wave of the panel survey
  • Study the productivity of the sheep performance system
  • Analyse the effectiveness of predator control
  • Work towards integrating the science and the management data

Executive Summary

The Karoo Predator Project was established in November 2011. Farm management data were collected in four waves (Nov 2012, Sept 2014, Oct 2015, Oct 2016). Analysis of this rich dataset is question-driven and is designed to learn as much as possible about the performance of the farming system. This work has been supported by two RMRDSA contracts (signed 12 November 2014 and 30 June 2016, Pretoria). This report covers all work conducted between January 2016 and July 2018. My main collaborators in this period were profs Nicoli Nattrass on human-wildlife conflict and Jenifer Piesse on farm productivity and farmer attitudes. Students and other colleagues were involved in specific papers.

Survey design and analytical approach

Wave 4 of the Karoo Management Survey was collected in November 2016 on the 2015 production season. This wave of the survey produced 55 useable responses which increased the number of observations in the panel dataset to 255. The three-wave dataset consisting of n = 200 observations was released for analysis in early 2016, and has been used since then to:

  • calculate a new estimate for predation losses for the Karoo
  • model culling effectiveness
  • estimate a stochastic frontier with inefficiency model which identifies opportunities for commercialisation
  • investigate the effect of grazing conditions on farm performance
  • model the structure of farmers’ risk perceptions
  • investigate the effect of information searching behaviour on farm performance

This list adds two outcomes to the original list of three analytical aims. Paper 3 is still under review at the South African Journal of Agricultural Extension, but was enthusiastically welcomed at the South African Society for Agricultural Extension’s June conference in East London and has since been shared with various producer and government stakeholder groups. Paper 4 is in the final review stage for special edition on the Karoo of the African Journal of Range and Forage Science.

The four-wave panel, released at the beginning of 2018, is currently being analysed by two honours students who are studying:

  • the stability of Karoo farmers’ risk perceptions, and
  • the effect of the 2016 drought on farm productivity

All papers in this series broadly share the same analytical strategy namely the quantitative analysis of questionnaire survey data. Methods depend on the question at hand and include descriptive statistics, principal component analysis, k-means clustering, OLS modelling, data envelopment analysis, and error components and technical efficiency effects stochastic frontier analysis.

A new estimate of predation losses for the Karoo

This analysis updates Van Niekerk’s estimate for the Karoo, which for the purpose of the study was defined as the Central Karoo, Cacadu, Pixley Ka Seme and Namakwa district municipalities.

According to Van Niekerk (2010) small stock farmers in the Karoo loses 13 thousand adult sheep, 393 thousand weaners and 517 thousand newborn lambs to predators every year. Since the latter figure is largely an impression, this category of potential losses was not considered in the Karoo Management Survey. Its estimates for predation losses in the Karoo is therefore much lower at 6700 adult sheep and 278 thousand weaner lambs. These figures represent a cost of approximately R278 thousand per year in current prices. When the same calculation is applied to both datasets, the predation figures for the Central Karoo converge on 5% (4.85% in 2008 and 4.7% for the period 2012-2014). This suggests that farmers were providing consistent estimates irrespective of the interview period or the timing of the survey.

A model of culling effectiveness

Models were specified to investigate the effect on livestock losses of culling predators. Farmers cull predators in response to livestock losses, and those who depend more on farming tend to cull more. Predator control however is probably counterproductive as culling is associated with greater subsequent livestock losses. This finding is robust to the inclusion of a set of socio-economic variables and farm characteristics. It is also consistent with ecological models which hypothesises that culling can create vacancies for dispersing juveniles to move into resulting in greater livestock losses later. The results of paired t-tests conducted across waves 1 and 3 of the panel revealed a great degree of churn in the use and perceived effectiveness of lethal and non-lethal methods which means that nobody has come up with a lasting solution yet. Given jackals’ ability to adapt to new control methods, a lasting solution probably does not exist even in principle. Much higher rates of poison use were reported in Wave 3, which is a concern because poison use is illegal, although it might simply reflect higher levels of disclosure rather than a change in practices. A model of the likelihood of using poison shows that poison is used by younger farmers and by people who experience large losses.  Lambing in pens close to the homestead did not matter. Another specification showed that farmers who believe that minor carnivores such as African wildcats, black eagles and crows were a problem too, were more likely to resort to poison, than farmers who were willing to accommodate this wildlife. This variable however lost statistical significance when socioeconomic controls were added to the model.

The key success factors in Karoo agriculture

To investigate the question of effective commercialisation, production data from commercial operations were used to benchmark farming in extensive grazing areas. The inputs in the technical efficiency effects model were stock sheep, labour, feed and animal remedies and fuel. The functional form was Cobb Douglas and the inefficiency model contained management experience, a dummy variable for a Grootfontein diploma and a dummy variable to indicate fulltime or parttime farming. The farm characteristics considered were  size, grazing conditions, a dummy variable to indicate flexibility and breed type.

The exercise revealed that every fifth commercial farmer in the sample is less than 50% efficient and therefore is as much in need of extension as any smallholder might be. Experience is an important determinant of performance and could be developed in the smallholder sector through appropriate vocational training. A commercial farmer needs at least eleven years of managerial experience to move from the bottom to the middle productivity cohort and a Grootfontein diploma adds eight percentage points to mean efficiency compared to any other configuration of education. Introducing a fiber component (wool, mohair) increases productivity by 13 percentage points. Sheep farming is amenable to smallholder production, because it can be done successfully on a part-time basis. The grazing index was significant but carried the incorrect sign. If all six farm and farmer characteristics identified in the model are set at the optimal levels a farm’s predicted level of productivity rises by 50%, which if incorporated in extension programs will substantially enhance the Black Farmers’ Commercialisation Programme’s chances of success.

The drought

The effect of grazing conditions on productivity was pursued further in stochastic frontier error components model. Results show that during the period 2012-2014, which was a good year followed by two normal seasons, the best farmers were able to maintain productivity at around 93%, while the bottom third producers suffered serious productivity declines. Several bottom-third producers dropped out of wool and mutton production even before the drought started, while many more are expected to have failed since due to the drought.

Risk perceptions

Waves 1 and 4 collected Likert scale data on farmers’ risk perceptions. Principal component analysis uncovered the structure of farmers’ risk perceptions. In round 1 the top threats were predators and rising input costs and the main components of farmers risk perceptions were institutional, market-related, rural safety and security and the environment. The environmental risk component combined drought and predators. OLS models explained individual risk scores with profitability, share of income from farming and key demographic variables. Profitability and income diversification lowers risk perceptions. More experience and education were generally risk mitigating too. Farm size and the amount of time spent the veld explained environmental risk perceptions.

A second round of risk  data, collected during a politically more turbulent and drier period, revealed stable risk perceptions. Four new sources of risk were added in round 2, including weather weirding (a technical term to describe perceived departures from typical conditions), politics, fracking and uranium mining and prospecting. On the longer list, farmers bundled together market risk with regulatory and political risk, which show that risk perceptions are rapidly updated as new threats emerge. Predators were dropped from environmental risk which now focusses on drought / climate change.

Productivity and information searching behaviour

Wave 1 productivity scores (Conradie and Piesse, 2015, Agrekon) were correlated to farmers information searching behaviour on the topics of rangeland management, animal husbandry and predator management. For information on rangeland management farmers still turn to the retired FSD extension agent who is a fellow farmer. For animal husbandry information they rely mainly on breeders and buyers and the representatives of input suppliers and for predator management Niel Viljoen in the preferred source. Farmers do not think that the government has any experience in this domain. A preference for private sources of information correspond to higher levels of productivity than the use of public sources.

POPULAR ARTICLE

To follow soon

Please contact the Primary Researcher if you need a copy of the comprehensive report of this project – Beatrice Conradie on beatrice.conradie@uct.ac.za

Does short duration grazing work in grasslands?

Does short duration grazing improve livestock production, veld condition and climate resilience compared to other grazing systems in a mesic grassland of South Africa?

Industry Sector: Cattle and Small Stock

Research focus area: Sustainable natural resource utilization

Research Institute: Universtity of Cape Town

Researcher: Dr Heidi Hawkins

Research Team

Title Initials Surname Highest Qualification
Prof S Vetter PhD
A/Prof MD Cramer PhD
Prof V Muchenje PhD
Dr C Mapiye PhD
Mr AS Venter MSc
Ms N Mgwali BSc Hons

Year of Completion : 2018

Aims of the project

  • Overall we wish to test the alleged mechanisms by which short duration grazing (or Holistic Planned Grazing, HPG) “works” explicitly by looking at the underlying mechanisms at the fine scale and overall effects at the camp/farm scale and how these vary and interact with rainfall, temperature, time and specific camps. We wish to apply this understanding to inform efforts being undertaken by government and NGOs to generate sustainable and more commercial red meat production from communal rangelands and land redistribution farms in one of South Africa’s biodiversity ‘hot spots’.
  • At the scale of an experimental farm and experimental plots we test claims that high animal densities in HPG reduces selectivity during defoliation of key plant species leading to conservation of species composition (biodiversity), forage quantity and quality throughout the year
  • At the scale of the farm, plots and pot experiments we determine how grazing intensity (recovery periods /defoliation frequency x defoliation intensity) affects plant recovery.
  • At the scale of the farm and plot we test claims that trampling (from intense hoof action during HPG) results in increased incorporation of nutrients (litter, dung, urine) and water, resulting in increased soil organic matter, nutrients including carbon, microbial activity, soil water infiltration, and reduced compaction and erosion.
  • At the farm scale, we test claims that the increased forage quantity and quality HPG increases animal gain ha-1, meat quality and profit of marketable animals; and at the scale of the individual animal, that HPG results in improved average daily gain per animal, including sufficient nutrition for pregnancy, lactation and re-conception.
  • At the farm and animal scale, we test whether high animal densities alter animal behavior (walking, resting, grazing) and energy expenditure.
  • Also on the individual animal scale, we test whether HPG results in a reduced parasite load (specifically ticks) because of, e.g. rapid movement of animals between camps, and whether the stress of movement compromises disease resistance.

Executive Summary

It has been claimed that Holistic Management (HM) and specifically, Holistic Planned Grazing (HPG, hereafter holistic grazing), can reduce desertification and reverse climate change by using livestock as a tool. At the same time, high animal densities and stocking rates associated with holistic grazing are claimed to result in improved plant and animal production but with little evidence or suggested mechanisms for these changes. The project addressed these gaps in knowledge via a three-year trial and corral studies, fence-line contrasts of existing and long-term practitioners of holistic grazing in the grassland biome, and remote sensing over sub-Saharan Africa.

We found nuanced differences in forage utilization, plant selectivity by animals, litter production, as well as small differences in animal behaviour and more marked differences in forage quality and animal parasites between grazing approaches (continuous, season-long, four camp and holistic planned grazing) in the trial. Some of these differences depended on season, but in all cases the scale of these differences were not enough to affect overall plant or animal production. Thus, the season-long and four-camp approaches were more profitable than the holistic approach due to capital outlay ((fences ands water points for multiple camps, or herders to create virtual camps), with the break-even point for holistic grazing being two years after that for other approaches. Provisional results from a national survey of long-term working farms supported results from the three-year trial. The use of a corrals is associated with holistic grazing in communal livestock systems, and our work showed that if the starting condition of the rangeland was poor with bare ground cover above 12% then basal cover increased under corraling, i.e. at very high animal densities of more than 400 livestock units per hectare, but otherwise increased bare ground so that corraling as a tool may be useful but should be applied with caution. In a remote sensing study, we found that woody plant encroachment has increased by 8% over the last three decades over sub-Saharan Africa and that while this is largely driven by climate, fire and herbivory are important drivers so that judicious use of fire and livestock (possibly at high densities) could help reverse this trend, with implications for the global carbon balance and productivity.

Overall, if animal gain is the priority of a land owner, the additional labour and/or infrastructure associated with holistic grazing is not justified. However, holistic grazing may be useful for rangeland restoration or specific goals.

Useful applications of holistic grazing based on our data may be:

  1. Reduction of under-utilized plant standing biomass and/or creation of a litter layer;
  2. Reduction of external and internal parasite loads (from an already low infestation to slightly lower infestation in our data so the practical usefulness would have to be tested at high infestation rates);
  3. Increased forage quality in some seasons (from normal quality to slightly increased quality in our data);
  4. Possibly, to reduce woody plant encroachment (and runaway fires), especially if browsers are included.

Popular Article

Does holistic grazing improve livestock production, veld condition and climate resilience compared to other grazing systems?

by Heidi-Jayne Hawkins

Director of Research at Conservation South Africa and Honorary Research Associate at University of Cape Town; contacts hhawkins@conservation.org and heidi-jane.hawkins@uct.ac.za

Rangelands, a source of biodiversity and agricultural products, are under threat globally. It has been claimed by the Savory Institute that Holistic Management (HM) and specifically, Holistic Planned Grazing, can reduce desertification and reverse climate change by using livestock as a tool. At the same time, high animal densities and stocking rates associated with holistic grazing are claimed to result in improved plant and animal production but with little evidence or suggested mechanisms for these changes. A recent review of the literature found that holistic grazing has no impact on plant and animal production (Hawkins 2017). In general, any management approach that is adaptive can be expected to sustainably manage rangeland resources by considering both ecological processes and livelihoods. Holistic Management or the Holistic Management Framework (Savory and Butterfield, 2016) is such a framework. While the adaptive approach of HM is not contentious, the livestock management part of this framework has been the subject of debate since the 1980s. Holistic Planned Grazing (HPG; hereafter holistic grazing) describes an intensive, rotational, time-controlled approach much like short duration-, cell-, multi-paddock- and mob-grazing. In South Africa, it is commonly called high-density, short-duration stocking.

During holistic grazing, livestock are kept at high densities using fences or herders with the intention of mimicking free-moving herds of herbivores that are migrating or bunched by predators; and grazing rather than fire is generally favoured as a way of recycling soil nutrients. Our recent article (Venter et al 2017) discusses the great numbers, densities and diversity of herbivores that occurred in the past before mass extinctions and hunting associated with humans spreading over the earth, and it is indeed reasonable to think that higher densities or animals would be ecologically appropriate and that the current use of fire to manage rangelands could in part be replaced by herbivores including livestock. However, the claims made by Savory go beyond this and need testing. Considering the renewed debate and existing threats to our rangelands including grassland and savanna, we examined the evidence for claims and tested various possible mechanisms that could underly these claims ((increased production, nutrient cycling, plant utilization and reduced plant selectivity).

The project addressed these gaps in knowledge via a three-year trial and corral studies, fence-line contrasts of existing and long-term practitioners of holistic grazing in the grassland biome, and remote sensing over sub-Saharan Africa. The research was a collaboration between Conservation South Africa and academics including five researchers and five students from the University of Cape Town, Stellenbosch University and the University of Fort Hare.

The controlled study was conducted on sections of a private farm (30.351767°S, 29.043433°E near Cedarville Flats and 30.394363°S, 29.020521°E on slopes near Goedhoop), called Merino Walk within the Matatiele Local Municipality, Eastern Cape in the grassland biome. Each flats and slopes section was divided into holistic grazing, conventional four-camp rotation, and continuous season-long grazing treatments with the same overall HM management and stocking rate but different animal densities. A national survey of working holistic farms and their neighbours allowed us to broaden the scope of the work from the scale of a local trial to the national scale. Also, the survey allowed us to assess holistic farming over longer time periods than the three years farm trial, as well gain insights into real farms. The questionnaire can be found at https://www.surveymonkey.com/r/grazing_research_survey .

We found nuanced differences in forage utilization, plant selectivity by animals, litter production, as well as small differences in animal behaviour and more marked differences in forage quality and animal parasites between grazing approaches (continuous, season-long, four camp and holistic planned grazing) in the trial. Some of these differences depended on season, but in all cases the scale of these differences were not enough to affect overall plant or animal production and in winter animal production in the rotational treatments was relatively low. Provisional results from a national survey of long-term working farms supported results from the three-year trial.

The season-long and four-camp approaches were more profitable than the holistic approach due to capital outlay (fences ands water points for multiple camps, or herders to create virtual camps), with the break-even point for holistic grazing being two years after that for other approaches.

Looking closer at animal behaviour, there was no evidence that holistic grazing increases dung trampling, the number of steps taken or selectivity at the plant or patch scales. An interesting effect of holistic grazing was a reduction in tick infestation that is thought to be associated with the rapid movements of animals between the mobile camps, so that ticks do not have time to complete their life-cycles. Out of the three grazing treatments, tick counts were higher in the continuous herd compared to the holistic grazing and four-camp herd in spring and summer. In general, internal parasites were very low with faecal egg counts being highest in the hot-rainy season. Both tick and faecal egg counts were not at levels of concern for animal health regardless of treatment effects.

The use of a corrals is associated with holistic grazing in communal livestock systems, and our work showed that if the starting condition of the rangeland was poor with bare ground cover above 12% then basal cover increased under corraling, i.e. at very high animal densities of more than 400 livestock units per hectare, but otherwise increased bare ground increased, so corraling should be applied with caution.

In the remote sensing study, we found that woody plant encroachment has increased by 8% over the last three decades over sub-Saharan Africa and that while this is largely driven by climate, fire and herbivory are important drivers so that judicious use of fire and livestock (especially browsers, possibly at high densities) could help reverse this trend.

Implications

From our results in a mesic grassland:

  • Holistic grazing may be useful as a tool for specific purposes such as increasing the litter layer and reducing tick loads but does not increase production;
  • High-density grazing practices are less profitable than conventional season-long grazing or the four-camp approach;
  • Corrals at animal densities over 400 LSU ha-1 may be a useful disturbance regime for restoration of bare ground and increasing phosphorus concentrations for cropping but only on already disturbed ground;
  • Browser/grazer mix and fire may be useful tools managed to reduce woody plant (bush) encroachment (and runaway fires).

Information sources

Hawkins H-J. 2017. African Journal of Range and Forage Science 34: 65-75.

Savory A, Butterfield J. 2016. Holistic Management. A commonsense revolution to restore our environment (3rd edn). USA: Island Press. ISBN 9781610917445 (e-book).

Venter, ZS., H-J Hawkins, MD Cramer 2017.  Ecosphere 8 (10), http://dx.doi.org/10.1002/ecs2.1946

Venter ZS, Cramer MD, Hawkins H-J 2018. Nature Communications 9, 2272 http://dx.doi.org/10.1038/s41467-018-04616-8

Please contact the Primary Researcher if you need a copy of the comprehensive report of this project – Heidi on heidi-jane.hawkins@uct.ac.za