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The flesh-footed shearwater (Puffinus carneipes) is a migratory seabird that ranges widely across the Pacific and Indian Oceans. The principal breeding populations are in Australia and New Zealand. The only breeding site in eastern Australia is on Lord Howe Island. Despite it being afforded a high level of legislative protection, the population on Lord Howe Island has declined substantially during the last few decades. The total extent of nesting habitat in 2002 was 24.3 ha, a reduction of 13.4 ha (35.6%) since 1978. Loss of nesting habitat was associated with increased urbanisation, the adverse impact of which extended beyond the footprint of buildings and gardens. In 2002, overall burrow density was 0.123 per m2 and the total number of burrows was estimated to be 29,853 ± 5867, a decline of about 19.0% since 1978. A substantial decline in burrow density was evident in the colony where loss of habitat to urbanisation had been greatest. In 2002, 58% of burrows were occupied by breeding birds, and the total population size was estimated to be 17,462 breeding pairs. Breeding success (the proportion of eggs that produced fledglings) was 50%, but was lowest in the most urbanised colony. To avert further declines in the population of flesh-footed shearwaters on Lord Howe Island major changes in land use practices, enforced through appropriate legislation, are needed, together with reductions in the level of seabird bycatch in fisheries operations and in the amount of plastics that litter the world’s oceans.

In August 1994 a Bryde's Whale Balaenoptera edeni entered and became entrapped in the Manning River, New South Wales. The individual was an immature male of the rare pygmy form of Bryde's Whale: it was 10.3 m long and weighed approximately 7.7 tonnes. The whale remained in the river for 100 days, during which time observations were made of its movements, diving habits, feeding behaviour and body condition. Apart from the risk of stranding, the entrapped whale also faced the potential threats of starvation, entanglement in fishing nets, collision with boat traffic, and exposure to low salinity and high acidity. In view of these threats, a rescue bid was launched to return the whale to the ocean. Five rescue attempts were made the last culminated in the whale being successfully towed to sea and released several kilometers offshore. Despite its emaciated condition the whale was rescued from the river before the onset of ill health or irreparable physiological damage. The whale swam away strongly on release, ...

Prime mallee lands that once supported high densities of malleefowl, Leipoa ocellata in New South Wales have been extensively cleared for agriculture. Malleefowl are now restricted largely to more arid habitat. Given the added competition from introduced herbivores, there is concern that these marginal habitats may not contain sufficient food resources to support viable populations of malleefowl, particularly in times of drought. An opportunistic feeding strategy and omnivorous diet enable malleefowl to exploit a diverse array of food items. Vegetative and invertebrate food resources available to malleefowl in marginal mallee lands were monitored over a period of 1 year during drought. Food resources were varied, transient and patchily distributed. Composition and abundance fluctuated considerably, but potential food was never entirely absent. Despite the prevailing drought, food was obtainable throughout the year provided malleefowl adapted to the fluctuating availability of each of the various potential food resources. Reduced food resources in marginal habitat is not implicated as a major factor in the demise of the malleefowl. Food was most abundant between August and November, inclusive, due largely to the abundance of herbs, the diverse supply of buds, flowers and fruit on perennial shrubs, and the sporadic proliferation of cockroaches. Food availability was least, and therefore most critical, during February, March and June. The most favourable time of the year, in terms of available food resources, for the release of captive-bred individuals was during spring, around September.

The aim of this study was to describe the roosts of Nyctophilus bifax in littoral rainforest in Iluka Nature Reserve on the north coast of New South Wales. Radio-telemetry was used to track 17 bats in November 1988 (lactation season) and 11 in May 1989 (mating season) to 87 roosts in 49 trees within the littoral rainforest. The bats frequently changed roosts, which were clustered within a small area. During November, lactating females moved twins between diurnal roosts and some carried twins while foraging. Twins represented a load of up to 95% of their mother's bodyweight. Bats roosted communally in foliage and tree hollows, beneath peeling bark, among epiphytes, and between strangler figs and host trees. Hollows were used more frequently when bats were lactating, while the use of foliage roosts was greater during the mating season. Roosts were concentrated in four tree species, although a wide range of other tree species was used. Roost trees used in November were taller (17 m) than those used in May (8.2 m), and reflect selection of Syzygium leuhmannii and Acmena hemilampra, both trees of the forest interior. The converse applied for selection of Cupaniopsis anacardioides, a small tree of the littoral zone, in May. These results identify the need for conserving a diversity of roosts for this species of bat.

On Australian semiarid floodplains, large herbivores such as kangaroos have a role in the cycling of energy (carbon) through the mechanism of feeding and defaecation of vegetative material. The degree to which kangaroos are vectors of energy within this system is not fully understood. This study describes the stable carbon isotope signature of floodplain plants and kangaroo scats at two close study sites. Kangaroos were found to deposit scats that mirrored the forage composition at each particular feeding site. Scats were 3.94‰ higher in δ13C values at the site where C4 grasses were available, indicating that this grass contributed ~25–30% of the diet of these kangaroos. The difference in diet due to the relative availability of C3 and C4 forage, detectable in the carbon stable isotope signature of scats, is used to demonstrate that kangaroos are recycling and redistributing energy locally, rather than transporting it more broadly across the floodplain.

Introduction This chapter investigates the mobility, home range and habitat utilisation of red and western grey kangaroos on Kinchega National Park and Tandou between 1979 and 1982. Of particular interest was how far kangaroos moved within Kinchega, how this compared with movements outside Kinchega, and to what degree, if any, these movements were constrained by the fence surrounding Kinchega. Red kangaroos inhabit the harsh dry environment of inland Australia. Australians think of them as highly nomadic creatures that regularly move hundreds of kilometres in search of greener pastures. This high mobility is consistently invoked to account for the marked changes that are sometimes observed in their dispersion. Scientific evidence conflicts with this view. There is no doubt that some kangaroos move long distances. Bailey (1971) recorded that red kangaroos moved up to 216 km away from his study area in north-western New South Wales during a severe drought. Denny (1982) recorded that a red kangaroo moved from Tibooburra in New South Wales to Lake Frome in South Australia – a distance of more than 300 km. However, many kangaroos remain in the same area for several years. Frith (1964) sighted a conspicuous group of red kangaroos eight times from November 1960 to August 1961. All sightings were within a circle of 5 km diameter. Bailey (1971) tagged 143 kangaroos. Twenty-eight were sighted within 8 km of the release site after a period of six months.