The impact of changing joining rates on the Western Australian sheep flock
Kate Pritchett (DPIRD, Albany WA)
Author correspondence: Kate.Pritchett@dpird.wa.gov.au
Executive Summary
Given the poor seasonal conditions and low prices experienced in 2023-24, the Western Australian (WA) sheep industry is experiencing a period of very poor industry sentiment often compared to that seen in the 1990s following the collapse of the wool reserve price scheme.
These difficult times mean producers have had to make production decisions for their businesses which may have flow-on effects for the entire state flock.
One commonly discussed option by industry and consultants was to join less ewes to reduce the feed burden on-farm and help mitigate losses due to low prices.
Computer modelling was used to investigate the impact of reduced joining rates on the WA flock over 3 years.
The results ranged from a 12% flock reduction from 11.96 million sheep to 10.52 million sheep over 3 years when the joining rate declined from 91% to 85% for one year, to a 35% reduction to 7.79 million sheep if the joining rate was reduced to 70% for all 3 years modelled.
This modelling found that the longer and more severe the reduction in ewe joining rates, the more severe the impacts on the state flock. This is also likely to occur simultaneously with a period of high turn-off and high loss rates which will exacerbate the impacts on the flock and make it very difficult for the flock to recover. This will have long lasting ramifications on the sheep industry and will impact all segments of the industry as well as supporting industries and regional communities in the long term.
When making joining decisions for the year ahead, producers have considered current seasonal conditions including their feed, water and cashflow availability, as well as the implications for their own flock structure which will, in turn, impact turn-off and the ability to re-build in future.
Introduction
The year 2023 was challenging for the WA sheep industry, with these conditions continuing in 2024. With the announcement by the Australian Government to phase out live sheep exports, coinciding with poor seasonal conditions in many regions; difficulty getting sheep to processors due to lack of kill space and very poor prices; industry sentiment and confidence is very low.
Some consultants and producers considered not mating all or part of their ewe flock for 2023 – 2024 in response to the market and seasonal conditions.
This may have longer term ramifications than just for the 2024 lamb drop, as it can affect the ability of the state flock to self-replace with less lambs born. It will also impact the wider industry with less animals for processing and exporting, and less wool produced, as well as impacting secondary industries such as shearing, transport and feed providers.
This computer modelling investigates the impact of reduced ewe joining rates on the flock size over the short term, between 2023-24 and the end of 2025-26.
Scenarios
To investigate the impact of reduced rates of ewe joining, multiple scenarios were run with different joining rates and for varying lengths of time. A baseline model was created to compare the results.
In addition to changing joining rates, adjustments were made to the length of time inthe following scenarios:
- Scenario 1 – the joining rate was altered for one year (2023-24) then returned to 91%.
- Scenario 2 – the joining rate was altered for 2 years (2023-24 and 2024-25) then returned to 91% for the following year.
- Scenario 3 – the joining rate was altered for all 3 years (2023-24 to 2025-26).
- Scenario 4 – the joining rate was altered for 2 years, then returned to 91% for 2025-26, along with an increased loss rate in 2023-24 of 7% to account for the possibility of sheep being euthanised on farm.
The proportion of ewes joined was calculated by dividing the number of ewes joined by the number of ewes on hand. The joining rate was then altered in 5% increments as listed below. Each of these joining rates was examined in each scenario:
- Baseline model – joining rate 91% for all 3 years.
- Joining rate 85%
- Joining rate 80%
- Joining rate 75%
- Joining rate 70%.
Discussion
As the joining rate declined, the impact on the flock increased, becoming more pronounced the longer it occurred.
In comparison to the baseline scenario, where the joining rate was unchanged at 91%, Scenario 1 had the smallest impact on flock size going forward. When the joining rate only declined for one year before returning to normal, the flock declined 12% from 11.96 to 10.52 million over the 3 years under an 85% joining rate (Figure 1).
In comparison, when the reduced joining occurred for 2 consecutive years (Scenario 2) the flock declined 15% from 11.96 million to 10.22 million by the end of 2025-26 under 85% ewe joining.
When the joining rate was reduced for all 3 years in Scenario 3 the flock declined 17% from 11.96 million to 9.93 million over that time under 85% joining.
When the loss rate was increased from 4% to 7% in 2023-24 while the joining rate was reduced from 91% to 85% for one year in Scenario 4, the results were quite similar to Scenario 3 with the flock declining 17% to 9.87 million sheep.
Comparison of the flock size of the baseline (91%) to each of the scenarios (Sc) at an 85% ewe joining rate.
As illustrated in Figure 2, the results become more extreme when the joining rate is reduced further, to 70%.
In Scenario 1, the flock declined 19% from 11.96 million to 9.65 million sheep over the 3 years under a 70% joining rate.
Scenario 2, where the joining rate was reduced to 70% for an extra year, resulted in the flock declining 27% to 8.67 million, whilst Scenario 3, where the joining rate was reduced to 70% for all 3 years, resulted in the flock falling 35% from 11.96 million to 7.79 million.
The extra year of reduced joining also had a more detrimental effect than increasing the loss rate from 4% to 7% in the first year combined with 2years of reduced joining (Scenario 4) at a 70% joining rate. In that instance, the flock declined from 11.96 million to 8.35 million, a fall of 30% rather than 35% which was seen when the joining rate stayed low for all 3years (Figure 2). This was because in Scenario 4 the joining rate returned to 91% in 2025-26 allowing the flock to plateau, whereas in Scenario 3 it didn’t get this opportunity as the joining rate stayed at 70% for the final year modelled.
Comparison of the flock size of the baseline (91%) to each of the Scenarios at a 70% ewe joining rate.
Conclusion
This modelling investigated the impact of reduced ewe joining rates on the WA sheep flock over the short term, between 2023-24 and 2025-26.
The longer the reduced rate of ewe joining occurred and the lower the rate of joining, the more severe the impact on the state flock. This was compounded by high turn-off rates and high loss rates which made it very difficult for the flock to recover.
At best, when the joining rate declined for one year to 85% before returning to baseline, the flock declined 12% from 11.96 to 10.52 million over the 3 years modelled.
The worst-case scenario occurred when the joining rate was reduced for all 3 years to 70% rather than 91%, which resulted in a 35% flock decline from 11.96 million sheep to 7.79 million sheep by the end of 2025-26.
Despite the current pessimism in the industry, it is likely that after 1 – 2 years of reduced ewe joining rates and high levels of turn-off, producers may start looking to rebuild flocks. Seasonal and market conditions may have improved, allowing producers to feel more confidence in the industry. It is also likely that producers who intended to exit the industry would have done so by this time.
Possible avenues to grow the flock include increasing joining rates and reducing turn-off by either keeping older ewes that would normally be sold, keeping more ewe lambs/hoggets and/or keeping more wethers.
Regrowing flocks when conditions improve may be a slow process due to the loss of replacement ewes in the short term, and may also involve reduced income if producers need to reduce the number of animals turned-off. This is on top of the reduced turn-off they may experience whilst reducing joining rates due to a declining flock.
The decision whether to reduce joining rates is highly dependent on the individual enterprise. While this modelling provides indications of possible sheep numbers going forward under various scenarios at the state level, enterprises will have considered their individual circumstances including feed and water supplies at hand, cashflow constraints and long term objectives in the decision-making process.
For up-to-date information on the production, consumption and trade (domestic and international) of sheep meat and wool in Western Australia see the West Australian sheep and wool industries webpage.