The impacts of a range of farm-management practices on house mouse (Mus domesticus) populations were tested in a large replicated field study in a complex irrigated farming system in southern New South Wales, Australia. An advisory panel, made up of farmers, extension officers, industry representatives and scientists developed a series of best-practice farm-management actions to minimise the impact of mice. Twelve experimental sites were split into six treated sites, where farmers were encouraged to conduct the recommended practices, and six untreated sites, where farmers conducted their normal farming practices. Mouse abundance was generally low to moderate for the 4-year project (5–60% adjusted trap success). We found significant reductions in population abundance of mice on treated sites when densities were moderate, but no differences when densities were low. Biomass of weeds and grasses around the perimeter of crops were significantly lower on treated sites because of applications of herbicide sprays and grazing by sheep. We could not detect any significant difference in mouse damage to crops between treated and untreated sites; however, levels of damage were low (<5%). Yields of winter cereals and rice crops were significantly higher on treated sites by up to 40%. An analysis of benefits and costs of conducting farming practices on treated sites compared with untreated sites showed a 2 : 1 benefit to cost ratio for winter cereals, 9 : 1 for rice and 4 : 1 for soybeans.

Although there have been a number of studies that have examined the effects of rabbits on pasture, the relationship between rabbit density and pasture degradation caused by rabbits has never been quantified. An experiment was conducted at Cowra, New South Wales, from October 1984 to October 1987, to determine the impact various densities of rabbits have on pasture composition, indices of pasture biomass and ground cover. Using plots set stocked with the equivalent of 8 sheep/ha (the district average) and 4 densities of rabbits as treatments, 0,�24, 48 and 72 rabbits/ha, the consequences of rabbit grazing were investigated.Pasture composition changed with season, year and rabbit density. Cumulative effects were also evident. Rabbits severely depleted improved pastures of legumes (subterranean clover particularly), with grass cover increasing proportionate to rabbit density. In the final year of the experiment, the rabbit-free treatment had 31% legumes and 25.2% grasses, whereas the highest rabbit density treatment had 6.2% legumes and 47.4% grasses. Indices of pasture biomass were highest in the zero rabbits/ha treatment and lowest in the 72 rabbits/ha treatment. More bare soil was exposed in the highest rabbit density treatment. Once seasonal and year effects were accounted for, the relationship between rabbit density and percentage damage was positive.

Foxes were killed in each of 4 seasons in the 5 years 1969-73 and a table gives numbers of stomachs with food for each year and season in each of 6 regions into which New South Wales was divided according to climate, vegetation and land use. Incidence of 11 food items or classes of food varied with region. An appendix lists precentage and volume of food items for the 811 foxes with food, out of the 899 that were killed. Main foods were rabbit, sheep and house mouse, by number and volume. The number of plant and insect items was high but the volume was low. Food included reptiles, amphibians, fish, grass and fruit. Foxes seemed to be opportunists and scavengers; food included feral pig and kangaroo when those were being shot locally, sheep carrion in the lambing season, mice during a plague of mice, domestic fowl, birds and animals probably killed on the road, and blackberries and apples in season. Insects included maggots, locusts and processionary caterpillars.

Much research, time and money have been invested in the control of rabbits in Australia, yet the relationship between rabbit density and livestock production losses has not been quantified. We experimentally investigated the variations in sheep production parameters caused by 4 densities of rabbits, 0, 24, 48 and 72 rabbits/ha. Medium to strong wool merino wethers were run at a constant stocking rate in replicated plots with rabbits at 4� different densities. Sheep liveweight and body condition and wool production variables were measured over 3�years. Low to medium densities of rabbits were not found to reduce liveweights of wethers, whereas wethers run with the high density of rabbits were significantly lighter. The presence of rabbits reduced the body condition of sympatric sheep with the lowest body condition recorded at the high rabbit density. Mean greasy fleece weights, wool yields and clean-fleece weights were significantly different between densities of rabbits. Wethers run with the high rabbit density grew less wool than the wethers run with the other 3 densities of rabbits. The cumulative gross return per ha from wool production was highest for the medium rabbit density and lowest at high rabbit density. At the conclusion of this short-term experiment, the presence of some rabbits enhanced returns from wool production because of lower fibre diameter and comparable clean-fleece weights of fleeces grown at low and medium rabbit densities. These production characteristics might have been caused by synergistic effects on pasture growth or a sheep stocking rate that was too conservative for the prevailing seasonal conditions. At high rabbit density, competition for pasture between rabbits and sheep overrode possible synergistic and understocking effects. The economic implications of the presence of rabbits on merino sheep production are discussed.

In Kinchega National Park, where there is no domestic stock, stomachs were examined of 99 foxes; there was food in 95 of them. Food was mainly rabbits except in autumn, when it was mainly insects and centipedes were an important item. Occurrence and relative importance of other foods are discussed.