The Chiltern-Mt Pilot National Park falls within the Victorian Riverina and Northern Inland Slopes sub-
bioregions. The park supports over 600 native species of flora and has the most intact assemblage of fauna with more birds, mammals and reptiles recorded than any other Box-ironbark forest.
Fauna The park supports a diverse range of native fauna with 276 different species of mammals, birds and reptiles being reported. It is listed as a threatened species under the
FFG Act 1988. The gliders have highly specific feeding and nesting requirements and use trees to move through the landscape. Consequently, they are highly susceptible to changes in forest conditions. Squirrel gliders have a reported home range size of approximately in northeast Victoria. This size can vary greatly and is strongly influenced by the availability of food and the quality of the forest habitat. Most of their time is spent in living eucalypt trees with a strong preference for large, mature trees in flower. They breed once per year with all males dying at the end of each breeding season. The average home range size for females is and for males it often exceeds . For these reasons, sites that offer mature, evenly spaced trees and well connected patches are considered the most suitable habitats. As a predator, the owls have comparatively low abundance and require a constant source of high-energy food which makes them particularly vulnerable to habitat fragmentation and degradation. They are considered to be nationally endangered with a population of approximately 1500 individuals remaining. Honeyeaters observed in northeast Victoria demonstrate a preference for box-ironbark forest, particularly the nectar from yellow gum (
Eucalyptus leucoxylon) and winter flowering red ironbark (
Eucalyptus tricarpa). Other significant flora species found within the park are described below.
Red ironbark Red ironbark (
Eucalyptus sideroxylon), also known as mugga ironbark, grows to a height of in open forests along the inland slopes of the Great Dividing Range in Victoria, New South Wales and southern Queensland. Flowering occurs throughout the year with seven small flower buds in umbels appearing in the axils of mature leaves. Leaf size is known to vary in response to environmental factors including water availability and soil composition. Both the swift parrot and regent honeyeater visit the park during winter to take advantage of the red ironbark's peak flowering period. The monoecious species is wind pollinated and described as having mostly erect branches, tough furrowed bark and dark green foliage. The species exhibits strong drought tolerance and an ability to survive in densely crowded strands though the rate of maturation can be slowed under these conditions. The species is described as having a hairy stem that grows to approximately in height, a single basal leaf and light green to yellow coloured flower with pale red shading. The deciduous herb originates from a population of approximately 100 individuals located inside a radius in the Mt-Pilot section of the park. The evergreen tree grows to a height of and flowers predominantly between November and December on a two to three-year cycle depending on environmental conditions. Seedling establishment is affected by common factors including temperature, light, litter accumulation, grazing, fire, frost and insect predation. == Environmental threats ==