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Making management decisions (e.g. livestock sales and feeding) that involve predicting future weather conditions is difficult, especially in variable climate s like the southern Australian rangelands. This project assessed tactical management options and trigger points using modelling to inform flexible stocking decisions. The study focused on a lamb production system on chenopod shrubland at Balranald, NSW Australia. A focus group of producers held in March 2019, during a lengthy drought, identified August as a key decision point for adjusting ewe numbers based on available feed. The SGS pasture model was validated for this location against historic vegetation and animal data from grazing studies, the GRASP model and producer experience of feeding periods between 2016 and 2020. Five different grazing systems were modelled. A base system of Merino ewes with lambs sold on 1 November that were containment fed with grain during periods of feed deficit was compared with two flexible options that adjusted livestock numbers in relation to available feed. The first was to reduce ewe numbers by half when green herbage mass was <0.7 t DM/ha in August (Flex ewe). The second was to retain lambs to 50 kg if green herbage mass in October was either > 1.2 t DM/ha (Flex lamb – 1.2) or >0.5 t DM/ha (Flex lamb – 0.5). The fifth system was to retain lambs to 50kg regardless of available feed (50kg lamb). The flexible ewe sale strategy reduced gross margin by 11% from $23.04 to $20.55 (per DSE; based on the long-term carrying capacity), due to lower income in the recovery years. The flexible lamb sale strategies (Flex – 1.2 – $26.76 and Flex – 0.5 – $33.30) were also lower than retaining lambs to 50 kg ($35.84). While modelling suggested lower returns from adjusting stock numbers in relation to trigger points identified by producers, other practical considerations such as experience with supplementary feeding also need to be considered.