Mound characteristics and behaviour of the orange-footed scrubfowl in the seasonal tropics of Australia

Seventeen site characteristics associated with the location of incubation m ounds of the Orange-footed Scrubfowl Megapodius reinwardt were measured for three habitat types: monsoon forest, regeneration forest and a sandy coast al vine thicket adjacent to an intertidal zone. The three habitats differed with respect to shrub cover, litter cover, canopy cover and several tree m easurements. Mound sites differed from random sites with respect to several variables, and these differences can be attributed to the litter-collectin g activities of the birds, which disrupt the vegetation on and near the mou nds. Internal mound temperatures were recorded over a 12 month period in 10 active mounds, two disused mounds and at two control sites. Active mound t emperatures in all three habitats were similar despite significant mound si te differences, particularly with respect to canopy cover and incident sola r radiation. Whereas the de-composition of litter was the primary sourer of heat for the mounds in the monsoon and regeneration forests, both solar ra diation and microbial decomposition contributed to the heal of the mounds i n the sandy coastal vine thicket. Soil temperatures in disused mounds and a t control sites decreased with the onset of monsoonal rains, hut active mou nd temperatures remained stable during this period. Behavioural observation s were recorded over a 19-week period for a pair of Orange-footed Scrubfowl at an active mound. The collection and incorporation of leaf litter into t he mound increased significantly as monsoonal rains intensified. The birds were most active during the early morning period. Hatchlings and juvenile b irds were observed in the study area throughout the eight months of field w ork and one colour banded bird was observed defending two mounds on several occasions.