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The conc. of 1080 (sodium monofluoroacetate) in dry muscle, organs, and stomach contents of rabbits poisoned by eating baited carrots ranged from 0.004 to 0.423 mg/g. Stomach contents (mainly masticated carrot bait) and livers contained the highest concn., followed by stomach tissue, kidneys, heart, and muscle. The total 1080 content in rabbits ranged from 0.01 to 4.88 mg. The risk of secondary poisoning in animals eating rabbits poisoned by 1080 was evaluated using 2 methods. Foxes, dingos, dogs and cats probably face the greatest risk of secondary poisoning. The extent to which other carrion-eating animals, particularly birds and small dasyurids, are at risk depends on their feeding habits and wheter they are able to vomit or develop an aversion to the taste and smell of 1080. Secondary poisoning can be minimized by using the minimum effective concn. of 1080 in baits and by removing the dead animals from the treated area.

Populations of non-target birds and mammals on a semi-cleared grazing property near Braidwood,
New South Wales, did not appear to be affected by a trail-baiting campaign against rabbits, Oryctolagus
cuniculus, using pellet bait and 1080 poison. Rabbit numbers were reduced by about 90% and those
of the fox, Vulpes vulpes, another exotic pest, by about 75%. Populations of both pest species began
recovering soon after the campaign, indicating the need for continued control measures.

Both fermenting wheat and bran/pollard pellets were readily accepted as bait throughout the year by feral pigs (Sus scrofa) in Namadgi National Park, Australian Capital Territory. Birds mainly ate wheat bait, particularly during winter. Other animals occasionally fed on both types of bait, mainly during autumn and winter. Covering baits with forest-floor litter did not significantly affect their discovery and consumption by pigs or by other animals. The proximity of the pigs to the bait line and their appetite for bait appeared to be the main factors responsible for seasonal differences in bait consumption. Trail-baiting campaigns against pigs in similar hill country areas are likely to be more effective during late autumn than other seasons because more pigs are likely to be close to the trails then and more quickly find and eat greater quantities of bait.

Meat baits injected with '1080' poison (sodium monofluoroacetate) according to the method recommended by the Department of Agriculture, New South Wales, Australia, for preparing baits for poisoning compaigns against wild dogs (Canis f. familiaris) and dingoes (C. f. dingo), began to lose their toxicity from the moment of preparation onwards, particularly after different rainfall treatments and when inhabited by calliphorid larvae. The main or most likely reasons for the loss of fluoroacetate were consumption by maggots (mainly larvae of Calliphora augur and C. stygia plus some C. hilli and C. tibialis) and their subsequent disappearance from the baits, leaching by rainfall, defluorination of the fluoroacetate by micro-organisms, and leakage from the baits after injection and during their decomposition. During this study the baits remained toxic to dogs, despite different rainfall treatments, for over 32 days during winter when maggots were absent, and for 6-31 days during summer, when they were present. Under the same conditions the baits contained an LD50 for an average-sized tiger quoll (Dasyurus maculatus) for 4-15 days and 2-4 days, respectively.

Populations of birds and small mammals in a mountain forest area of New South Wales were not significantly
affected by two trail-baiting campaigns involving 1080 poison that were carried out against wild dogs,
Canis familiaris, during the winters of 1980 and 1981. Factors which probably minimized the effect on
the non-target species were the sparse distribution of baits, the placement of the baits in habitats not
favoured by small mammals, their initially rapid rate of removal by foxes, Vulpes vulpes, the dietary
preferences of the non-target animals and the low risk they would face if they did consume a bait.

Nine wild dogs, Canis f. familiaris, radio-tracked over periods of 28-61 days in Kosciusko National Park,
N.S.W., occupied home ranges of 220-5420 ha (mean 2193 ha). These home ranges were similar in size
to those observed for dingoes, C. f. dingo, in other areas of south-eastern Australia. The maximum
distance that any of the nine dogs moved between successive daily locations was 11.2 km. On the basis
of this information and that obtained by others, we suggest that the control of wild dogs on Crown
Land in south-eastern Australia should be confined to those areas adjacent to private grazing land.
Furthermore, a control zone 12-20 km wide should be adequate.
Two successive trail-baiting campaigns with 1080 poison in March and April 1982 killed only two
(22%) of the nine wild dogs carrying radio transmitters. Traps, in comparison, caught 15 out of 27 (56%)
of the dogs known to be in the area. The main factors which reduced the success of the poisoning
campaign were the rapid loss of toxicity of the baits after their distribution, the rapid rate at which
they were removed by other animals, particularly foxes Vulpes vulpes and birds, and the dogs' apparent
preference for natural prey.