Mistletoe and birds

This follows on from two previous posts on Mistletoes (here and there).  My principal reason for following up was receiving some comments suggesting that mistletoes were absent from the higher country because Mistletoebirds (Dicaem hirundinaceum) do not occur in the higher wet forests. (Steve Wilson's definitive book "Birds of the ACT: Two Centuries of Change" notes that a few Mistletoebirds were banded in the mountains but ".. it is rare in the ranges.".)

It seemed strange that Watson and Herring show mistletoes to be a keystone resource if the plants are so dependent on a single species of bird.  

According to them - both from their bibliography and the references in the text -the key resource on mistletoe- bird interaction is still "Reid N  "Pollination and seed dispersal of mistletoes (Loranthaceae) by birds in southern Australia." published in  "The Dynamic Partnership: Birds and Plants in Australia" Ford and Paton (eds) 1986.  It seemed like an interesting volume, despite its vintage, so a copy was acquired (thank you Lost and Found Books).  As well as the article by Reid, "Forde N "Relationships between Birds and Fruits in temperate Australia." " was relevant to my enquiries.

The following table contains all species identified by Reid as feeding on nectar or seeds from Mistletoe species.  In addition the species shown in green were reported by Forde, but not by Reid.  The species marked in red are those which are considered by Reid (in another paper) to be the only species "undeniably involved in mistletoe dispersal".

ACT status	nectar feeders	seed feeders
COMMON	Striated Thornbill	Gang-gang Cockatoo
	Brown Thornbill	Galah
	Eastern Spinebill	Crimson Rosella
	Yellow-faced Honeyeater	Eastern Rosella
	White-eared Honeyeater	Fuscous Honeyeater
	Noisy Miner	White-plumed Honeyeater
	Brown-headed Honeyeater	Red Wattlebird
	Noisy Friarbird	White-naped Honeyeater
		Black-faced Cuckoo-shrike
		Olive-backed Oriole
		Pied Currawong
		Grey Currawong
		Australian Raven
		Little Raven
		Silvereye
		Common Starling
		Common Blackbird
		Mistletoebird
LESS COMMON	Yellow-tufted Honeyeater	Emu
	Scarlet Honeyeater	Cockatiel
	Crescent Honeyeater	Little Lorikeet
	New Holland Honeyeater
	Masked Woodswallow
	White-browed Woodswallow
RARE	Chestnut-rumped Thornbill	White-fronted Honeyeater
	Lewin's Honeyeater	Spiny-cheeked Honeyeater
	Tawny-crowned Honeyeater	Little Wattlebird
		Regent Honeyeater
		Painted Honeyeater
NOT RECORDED IN ACT	Purple-crowned Lorikeet	Brown Cuckoo-Dove
	Inland Thornbill	Rose-crowned Fruit-Dove
	Purple-gaped Honeyeater	Red-winged Parrot
	Yellow-plumed Honeyeater	Blue Bonnet
	Grey-fronted Honeyeater	Mulga Parrot
	Brown Honeyeater	Australian (Mallee) Ringneck
	White-cheeked Honeyeater	Pied Honeyeater
	White-throated Honeyeater	Singing Honeyeater
	Yellow-bellied Sunbird	Yellow-throated Miner
		Grey Honeyeater
		Striped Honeyeater
		Little Crow
		Torresian Crow
		Metallic Starling

The two columns show that some species are known to take nectar from the flowers (playing an important role in fertilisation of the species) while others are known to be frugivorous.  Several authors note that some of the seed eaters - especially the parrots and their close relatives - are seed predators in that they damage the seeds beyond the ability to germinate.

I have also categorised (heuristically I am afraid) the bird species according to their occurrence around Canberra.  Of the birds common around Canberra, the Mistletoebird is the only 'proven disperser' of mistletoes but there are a good number of non-predator seed feeders in the area.  Many of these, including Red Wattlebird. White-naped Honeyeater, and Pied Currawong are common in the Ranges and could be expected over a number of years to have introduced mistletoe seeds to the area.

That we have not recorded Amyema sp. in the Ranges cannot be due solely to the absence of Mistletoebirds.  I suggest next time a WW goes into the Brindabella Ranges keeping an eye upwards would be a good idea !