In coastal heath, 12 km north of Sydney, Banksia ericifolia set fruit after cross-pollination but not after controlled self-pollination. Animals removed nectar and pollen from inflorescences during the day but not overnight. Introduced honeybees (Apis mellifera) and native birds (Meliphagidae, Zosteropidae) visited flowers frequently during the day, carried pollen on their body surfaces and were likely to transfer pollen between plants. Native bees, nocturnal moths and ants also visited flowers but were too infrequent, did not move between plants or foraged inappropriately to be important pollinators. No mammals were seen visiting flowers and the small mammals we caught carried no pollen. Exclusion experiments confirmed that pollination occurred during the day and not at night, but the experiments were insufficient to determine the relative importance of honeybees versus birds as pollinators. Only about 3% of the flowers of Banksia ericifolia developed follicles under natural conditions. Follicle production in this species was limited by resources and not by pollinators, since multiple cross- pollinations of flowers did not increase follicle production above the natural rate.

Acacia pycnantha secreted extrafloral nectar during winter. This coincided with flowering and not with herbivore damage to phyllodes. Phyllodes with axillary racemes or phyllodes towards the tips of branches were more likely to have nectar secretions than phyllodes without axillary racemes or away from the tips of branches. Although most phyllodes were damaged by herbivores to some extent, this damage had occurred prior to the secretion of extrafloral nectar in winter. Further damage to phyllodes was negligible during winter. A variety of birds, including silvereyes and several species of honeyeaters and thornbills, consumed extrafloral nectar and in the process brushed against inflorescences. The activity of these birds in Acacia pycnantha, relative to their use of other plants, increased during the period of nectar secretion. When birds were excluded from flowering branches by mesh, pod production was significantly reduced. Natural rates of pod production were low and variable. These observations and results strengthen the role of birds as pollinators of Acacia pycnantha and we argue that these extrafloral secretions aid pollination and not reduction in herbivore damage in Acacia pycnantha.

New Holland honeyeaters obtain negligible nutriment from pollen. Three lines of evidence show that the contents of pollen grains are not extracted during passage through the birds. Firstly, the proportion of empty pollen grains in faecal samples did not differ from that in samples of pollen dusted off the facial feathers of wild birds. Secondly, the proportion of empty pollen grains in samples taken at successive points along the alimentary canal from oesophagus to cloaca did not change in the 10 birds examined. Finally the condition of pollen fed to caged birds did not change with passage through the birds. Quantities of pollen ingested by honeyeaters are small, around 300,000 pollen grains or 15 mg of pollen per day. Even if fully digested this uould provide only a small proportion of the birds' protein requirements and a negligible amount of energy. Pollen is probably collected accidentally while the birds collect nectar from flowers.

Dietary preferences of the greater stick-nest rat (Leporillus conditor) and the European rabbit (Oryctolagus cuniculus) were compared using cafeteria trials and direct observations. Despite overlap, these species exhibited differences in dietary preference. L. conditor showed a strong preference for chenopod shrub species and other plant species with a high water content including Gunniopsis quadrifida and Calandrinia remota. L. conditor also preferred female bladder saltbush (Atriplex vesicaria) foliage to male. O. cuniculus ate a greater selection of plant species in most trials with their most preferred species including mulga (Acacia aneura), Salsola kali and Calandrinia remota. Both O. cuniculus and L. conditor preferred seedlings of perennial species to adult cuttings. L. conditor has recently been re-introduced to a 14 km� O. cuniculus, cat (Felis catus) and red fox (Vulpes vulpes) proof exclosure in the arid zone of South Australia. The re-introduction of this herbivore and the removal of exotic herbivores may change the vegetation structure and composition within the exclosure by restricting growth of some succulent chenopod species but allowing the regeneration of tall shrub species such as Acacia aneura which are usually limited by O. cuniculus grazing.

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