Variable rainfall in much of the
savannas makes sustainable and profitable grazing a challenge. At a
working cattle station near Charters Towers, an eight-year research
project has been looking at different stocking strategies to
deliver the best outcomes for the land, the cattle and the people.
By Fran Bancroft and Kate O'Donnell.
Results | Grazing land management |
Proactive management | Funding | References |
Above, heavily stocked grazing strategy
Healthier paddock under a lighter stocking strategy
Heavily grazed paddock on the left, spelled pasture ready for
grazing on the right
Photos: Peter O'Reagain
Much of past research in the grazing industry has focused on
animal production such as supplementary feeding, early weaning and
other measures to maximise livestock production. The Wambiana
project has shifted that focus on to the land and sustainable
management-by attempting a big picture of the whole grazing
system's response to how we manage grazing lands in a variable
Dr Peter O'Reagain and John Bushell from Queensland's Department
of Primary Industries and Fisheries (QDPI&F) have led the
Wambiana grazing trial for the past eight years. The project, is
co-funded by QDPI&F and Meat and Livestock Australia, but has
also received support from a range of other funding bodies. The
project aims to develop a set of best practices and guidelines for
graziers and over the life of the project has assessed the ability
of different grazing strategies to cope with rainfall variability
in terms animal production, economics and resource condition.
A 1041 ha section of the Wambiana property was leased for the
project and divided into paddocks to test five strategies. These
were heavy and light stocking, rotational wet season spelling,
variable stocking based on available pasture and finally, a
variable stocking strategy based both on available pasture and
Southern Oscillation Index (SOI) predictions for the coming wet
season (see box opposite). The trial is not only examining
production and economic performance, but also the effects on
pasture composition, biodiversity, woody vegetation and soil and
The test area has a highly variable rainfall-the annual average
is 653 mm, but the historical range is 109-1653 mm-and most rain
falls in January to March. During the first four years of the trial
rainfall was good, but has been below average for the last four
years giving a good indication of how variable the rainfall can be.
The results are providing new facts and figures about sustainable
The Wambiana results clearly show that sustainability and
profitability go hand-in-hand in the northern savannas. Light or
relatively conservative stocking has consistently given superior
individual animal production, a shorter time to turn-off, reduced
costs and improved marketability and economic returns. Risk is
reduced, land condition maintained or improved and runoff reduced.
Variable stocking also performs well, but there is increased risk
and an increased level of management is required. Constant heavy
stocking performed well initially with the good rainfall, but land
condition declined and stock numbers could not be maintained
through the dry years without expensive drought feeding.
"In testing heavy stocking we are not recommending it, but we
have to know the consequences of applying this strategy," explained
In low rainfall years, the poor animal production and expense of
drought feeding under heavy stocking means that any economic
benefit from running more cattle is lost. Land condition also
declines and increased run-off means that when rain does fall it
does not stay in the land but carries soil and nutrients in to
waterways. In the longer term pasture production declines causing a
drop in carrying capacity.
Peter O'Reagain sees the results as showing that, despite
scepticism from some graziers as being not economically viable,
sustainable grazing is the only way forward.
"It's pretty exciting that the trial is showing that sustainable
management is not uneconomic but in fact very profitable," said
Peter O'Reagain. "It's showing good economic returns for a variety
of reasons: better quality of animals, shorter turn-off times,
reduced costs and higher rainfall use efficiency.
"Trial data show that over the last four dry years the heavy
stocking strategy has run at a loss while light stocking and
variable strategies have run at a consistent profit. So any gains
from running those higher numbers in the good years are being
rapidly eroded away: of course whether this situation reverses when
the good years return we just don't know," he said.
The Wambiana trial results are also important in supporting new
and existing extension and development programs. One of these is
the Edge Network's Grazing Land Management (GLM) workshops
delivered by QDPI&F and Meat and Livestock Australia. The GLM
package is tailored to each major region to help land managers to
manage sustainably and profitably in their own unique set of
"There is a whole section on management and stocking strategies
in GLM, and the main data comparing different management strategies
is from Wambiana," points out Marnie McCullough, Extension Officer
at QDPI&F. Marnie and other extension officers are working
closely with graziers and researchers to ensure that the
information and results flow to all parties. "The Wambiana trial is
a wonderful resource that we're very keen to promote and encourage
people to look at and understand-it's my job to make sure people
are hearing about that." According to Marnie, the management
strategy that works best depends on the level of management that an
individual landholder wants to invest in and their circumstances.
"If someone wants minimal inputs, the set stocking approaches are
attractive," she explained.
Variable stocking is based on assessing how much feed there is
at the end of the wet and adjusting cattle numbers accordingly.
Apart from the guidelines and principles from Wambiana, graziers
have a suite of existing tools available to help make such
decisions including pasture yield standards, the Rainman package,
Breedcow and Dynama herd budgeting.
However, strategies like variable stocking are still reactive
and stocking decisions are not made until the end of the wet season
when, according to Dr Greg McKeon from Queensland's Department of
Natural Resources and Water (QDNRW), the damage may already have
"What damages perennial grasses is heavy grazing through the
growing season in relatively dry years. So even if stock numbers
are adjusted, it is still possible to cause pasture degradation by
over-stocking when good seasons are followed by very poor years" he
"Climate forecasting is one tool that managers could use to be
more proactive in managing for variable seasons."
At Wambiana the SOI was successfully used to reduce stock
numbers before the dry years arrived. Currently, the SOI only has a
three-month lead-time, so the cattle were sold in November. Even
though this was less than ideal due to poor prices, Peter O'Reagain
said the strategy on the whole worked very well.
"The SOI strategy allowed us to cut stock before we ran into
trouble with the dry years, as happened under constant heavy
stocking. Economically, the strategy performed much better than
simply running at a very heavy or very low stocking rate," said
The SOI strategy was on a par financially with variable
stocking, but because of early de-stocking, had better results in
terms of pasture condition.
"Ironically, we had a very good wet season at the start of the
trial in December 1997, despite initial SOI predictions of a very
poor year. By keeping stocking rates low in 1997-98 you could argue
there was a potential loss of income," said Peter. "But in terms of
land management I don't think so.
"The way I see it, losses from being caught out by drought are
far worse than the money you might forgo by not having extra cattle
in a very good year."
While the SOI might currently be the best forecasting tool
available for Queensland, new forecast systems are being developed
for use here and in other parts of Australia. For example, the
CSIRO Oceans to Farms project is using Sea Surface Temperature
variations to predict rainfall and is using economic modelling to
evaluate the usefulness of predictions.
Greg McKeon helped develop the GRASP modelling system that has
been in use for many years. He aims to get the model working for
the whole of northern Australia and to train people in its use.
Similar projects are under way in Australia in NSW and the Northern
Territory, and overseas in Zimbabwe where GRASP is used to run
management and climate scenarios tailored to these regions. "Part
of these studies could involve simulation of the grazing strategies
being tested at Wambiana," said Greg. "El Nino affects the climate
in many countries. So the idea of linking management to warnings of
what's to come, could work around the world."
Pastures can take a long time to respond to management and
climate and Peter O'Reagain stresses the Wambiana trial isn't the
final word on these issues. However, the data is certainly some of
the best available and shows the costs and benefits of different
strategies. The important message is not that one strategy is
necessarily best, but rather that there are a set of principles and
guidelines that can be tailored to particular regions and
properties across most of northern Australia.
"From our experiences, I would say your best management must
involve spelling and assessing available forage and adjusting stock
numbers at least once a year," said Peter. "You should use climate
forecasting as an additional tool in making management decisions."
Understanding the carrying capacities applicable to your region and
land-types is the key.
"Be very careful with your stocking rate and know what the
limits are for your area as you change stock numbers with the
Several agencies and organisations contributed funding or
resources to the Wambiana project: the Tropical Savannas CRC, the
Great Barrier Reef Marine Park Authority, the Natural Heritage
Trust, the Drought Regional Initiatives and CSIRO.
1. Kutt, A. & O’Reagain, P. ‘Conservation
without cost’, Kraatz, M., Clark, M., Jacklyn, P. (Eds)
(unpublished), in The Bush Book: A management manual for small
areas of native bushland, Tropical Savannas CRC.
O’Reagain P.J. & Bushell J.J. 2003, ‘Effect of
grazing strategy on animal production in a seasonably variable
tropical savanna’, in Proc. VIIth International Rangelands
Congress, Durban, South Africa, July 2003, pp.
O’Reagain P.J., McKeon G.M., Day K.A. & Ash A.J. 2003,
‘Managing for temporal variability in extensive rangelands
– a perspective from northern Australia’, in Proc.
VIIth International Rangelands Congress, Durban, South Africa,
July 2003, pp. 799–809.
O’Reagain P.J. & Bushell J.J 2003. ‘The effects
of fire on woodland structure and density in a north Australian
tropical savanna’, in Proc. VIIth International Rangelands
Congress, Durban, South Africa, July 2003, pp.
CSIRO Livestock Industries, Rockhampton
CSIRO Sustainable Ecosystems
CSIRO: Oceans to farms
Determine a set of skilful and industry targeted climate prediction indices based on ocean data (such as SST) and intermediate-complexity coupled ocean-atmosphere models (eg. Kleeman, Cane-Zebiak) for specific agricultural regions across Australia.
Optimise the use of statistical and intermediate coupled ocean-atmosphere forecasts in farming production/economics models for the extensive grazing, dryland grains and sugar industries.
Assess the production, economic and resource-based value of these systems compared to current best-practice in the absence of climate forecasts.
Meat and Livestock Australia
Meat & Livestock Australia Limited (MLA) is a producer-owned company that provides services to livestock producers, processors, exporters, food service operators and retailers.
Southern Oscillation Index (SOI) and seasonal forecasts
This web site provides SOI data, graphs, reports, future rainfall probability maps and Sea-surface Temperature maps.