occurs in some habitats without the presence of bell miners, but there is a high correlation with bell miner presence and eucalyptus dieback that was noted as early as 1982. One theory is that the monopolising and/or farming of psyllids by bell miners allows psyllid numbers to build up, eventually leading to tree sickness and possibly death. In some cases where bell miners have been removed, the avian diversity has been restored and the psyllid infestation reduced to the point of trees returning to health. However, in other studies, the trees did not recover even after bell miner removal, so more research is needed to better understand the relationship between bell miners and eucalyptus dieback. Breeding Bell miners are generally sedentary, and thus have a permanent all-purpose territory, which includes breeding. The primary breeding season is April/May to August/September in the northern part of their range and June/July to November/December in the southern range, but breeding has been observed in all months of the year, as females will often nest again after a failed nest or once the young have fledged. One female was recorded nesting five times in one season, though that many nest attempts is unusual. Bell miner pairs are monogamous, but the breeding tasks are divided between the sexes. Female bell miners build the nest over 8 days, incubate the 1-3 (but typically 2) eggs for 14.5 days, and brood the young for up to 12 days, depending on the weather. The nests are small, cup-shaped, and built with dry twigs, grasses, and bark woven together with spider web. Nests are generally hidden in the foliage of dense understory plants, 3-5m above the ground. The eggs are typically 24mm x 16mm, oval shaped, and pink in color. They have darker reddish-brown spots and blotches, primarily over the larger end. Pallid cuckoos have been recorded as nest parasites for bell miners. While nests are all within the territory of the colony, they are not tightly packed as traditional colony breeders. Instead, nests are located within the breeding pairs' normal foraging range. They are generally within calling range of neighbour nests, but not too close. Female bell miners move nest locations after a nest failure, and were observed to move nests lower into the thick understory, likely reducing the risk of avian predators. However, they did not move nests far from the original location horizontally, possibly to stay within