Bell Miner

Bell Miners are strongly associated with psyllid (tiny insects that feed on leaves) infestations in gum trees Eucalyptus (causing the disease called 'dieback') and may even actively farm psyllids as a food source.

Identification

The Bell Miner is the smallest of the miners and is a medium-large and solidly built honeyeater. It is mostly olive-green, with a short, down-curved, bright yellow bill, a red-orange bare eye patch and orange-yellow feet and legs. It has a squared off tail. Males are slightly larger, but otherwise the sexes are similar. Young birds are duller and browner, with a paler eye patch. More often heard than seen, the Bell Miner lives in large colonies and aggressively defend their territories against all intruders.

Habitat

The Bell Miner is found manly in open eucalypt forests and woodlands with a dense shrubby understorey. Found mainly in the temperate zone in broad gullies of foothills or on coastal plains, often at edges of rainforest areas. They are also found in suburban areas, including remnant bushland, parks and gardens, especially around creeks or other water sources (e.g. swimming pools, bird baths), where eucalypts and dense shrubs have been retained.

Distribution

Endemic to eastern and south-eastern mainland Australia, the Bell Miner ranges from Gympie, Queensland, to Melbourne, Victoria, but is restricted to coastal and mountain regions.

Seasonality

Sedentary, with colonies usually remaining in same location for many years. Whole colonies will move as result of catastrophe e.g. bushfire or loss of water sources.

Feeding and diet

Bell Miners feed as part of a colony, remaining in the canopy at or above eight metres from the ground. They mainly eat insects, especially psyllids and their lerps (sugary secretions used as protective shelters by the tiny psyllid insects) from the foliage of eucalypts. They also eat nectar and manna. It has been shown that Bell Miners maintain psyllid populations at high levels by protecting them from other birds and by maintaining sufficiently large territories so that they don't over-feed on the psyllids themselves.

Communication

Sweet, musical, bell-like 'tink'. All birds in a colony call all day, with calls starting just before sunrise and finishing just after sunset. Also has a 'hiccupping' note and other harsher calls.

Breeding behaviours

Bell Miners have a complex social structure, based on breeding pairs which each have their own feeding range that overlaps with those of non-breeding members (e.g. their offspring), making up a colony of 8 - 200 birds. The breeding pairs generally mate for life and are 'obligate co-operative breeders', which means that they are always helped by between 1 and 20 'auxiliaries' in their parental duties. These helpers are usually young or unpaired birds, but may also include other breeding adults who are also raising their own young. They are usually closely related to the breeding pair, most often to the male. Interestingly, males of breeding age are the most 'helpful' auxiliaries, often helping more than one breeding pair. The helpers defend the nest, feed the young, clean the nest and sometimes feed the female when she is incubating the eggs. Both parents also engage in all nest and feeding duties, but the female builds the thin, cup-shaped nest and incubates the eggs alone. Predators of eggs and young include: Grey Currawongs, Laughing Kookaburras, Common Blackbirds, Brown Goshawks, ravens, Eastern Brown Snake and Copperhead. Can also be parasitised by cuckoos, including the Pallid Cuckoo and the Fantailed Cuckoo.

• Breeding season: All year round; mostly June to November.
• Clutch size: 1 to 3, usually 2
• Incubation: 15 days
• Time in nest: 15 days

Conservation status

The Bell Miner is adversely affected by the loss of dense shrubby vegetation along creeks and in gullies, especially as a result of fire and clearing for houses, roads and agriculture, as well as 'flood control' alterations to creeks. Occasionally killed by cats.

References

• Higgins, P.J., Peter, J.M. and Steele, W.K. (eds) 2001. Handbook of Australian, New Zealand and Antarctic Birds, Volume 5 (Tyrant-flycatchers to Chats). Oxford University Press, Melbourne.
• Longmore, N.W. 1991. The Honeyeaters and their Allies of Australia. Angus and Robertson and The National Photographic Index of Australian Wildlife, Sydney.
• Simpson, K and Day, N. 1999. Field guide to the birds of Australia, 6th Edition. Penguin Books, Australia.
• Frith, C.B. 1985. Garden Birds: attracting birds to Australian and New Zealand Gardens. Quarto Publishing, Doubleday Australasia, Sydney.