Why pick on me ?!

The colourful little bird pictured here is a male Mistletoebird. It is one of two specialist bird species, the other being the Painted Honeyeater, that feeds almost entirely on mistletoe fruit, although they can supplement their diet at times with insects and other fruit. Both species defecate the mistletoe seeds rather than regurgitate them after digesting the pulp. The sticky seeds need considerable pecking and wiping on a branch to release them from feathers around the vent. The widely-held belief that mistletoebirds deliberately turn side-on to deposit the seeds on a branch is apparently largely a myth. In his excellent book “Mistletoes of Southern Australia”, David Watson calls into question another widespread claim that the mistletoe specialists, Mistletoebird and Painted Honeyeater, account for the vast majority of newly-established mistletoe. Research shows that Mistletoebirds tend to stick to areas which already contain mistletoe, and it is the non-specialist mistletoe feeders, including a number of honeyeaters, the Olive-backed Oriole and the Silvereye, that may be the principal dispersers of mistletoe to new areas.

Historically the Mistletoebird has come in for a lot of flak, literally. David Watson quotes a 1939 letter to a beekeeping journal entitled ‘Mistletoe bird is spreading the mistletoe pest’:
“I have cut 26 mistletoe growths off only a fair sized Red Ironbark tree. I decided after some years of cutting off and pulling down to make war on the birds that were responsible, but found them a tougher problem than I expected, for I never guessed they were so numerous. I have destroyed well over twelve hundred [our emphasis] of these birds during the past six years, nearly all on my own property, and still there are a few coming in from other parts.”
This attitude was apparently shared by many landholders and even naturalists at the time, and persists to some extent even today, which is a pity as the Mistletoebird may prove not to be the main disperser, and  mistletoe itself should be recognised as an important natural component of the Australian environment. Excessive mistletoe is a result of over-clearing of understorey vegetation, creating environmental imbalances, with the loss of regulators such as possums and butterfly larvae which consume the foliage. It is surely better to rectify those imbalances rather than shoot the messenger!

At left is a nest photographed by Andrew on the Three Sisters property between Flowerdale and Strath Creek. The hanging purse-like shape with a side entrance looks to us like a typical Mistletoebird nest. Although usually made of plant down and cobwebs, this one is mostly wool, probably because there was a pile of sheep crutchings close by – a good example of opportunism. The female builds the nest and does all the incubating.

Incidentally, Mistletoebirds have been sighted in Tasmania in recent years despite there being no mistletoe in that state. Evidence of mistletoe has been found in the fossil record there, but it is unlikely that mistletoe populations will be re-established by birds from the mainland considering the rapid passage of seeds through the Mistletoebird’s gut and the long journey involved.

The audio below is of a Mistletoebird calling in synch with a Peron’s Tree Frog. Is it coincidence, or call and response?