Orange-bellied Parrots: weed dependent

[Ian May <>]

Hello Jon

Orange-bellied Parrots use a range of plants for food and habitat, determined by season and location.  In the OBP recovery plan 1984, (page 30) it states that studies at Point Wilson in Victoria by Lane and Loyn 1980, Chandler and Loyn 1981 etc. "found no evidence of birds leaving the area altogether as one source of food is depleted, more a local movement to different food supplies".   In a1981 NPWS study of Orange-bellied Parrots in South Australia by yours truly, it was found that the seeds of four food plants are important in their wintering range and Sea Rocket Cakile maritima, a common ephemeral plant that grows above high water on beaches is probably the most important as it provides an abundant source of food until winter storms bury and disperse the available seed.  Other food plants in SA are Acaena novae-zelandiae, Suaeda australis, and Sarcocornia quinqueflora.

Because of its absence in early botanical collections, some botanists doubt that Sea Rocket is native to Australia.   In that context, it could be classified as a weed however others say that because of its method of floating seed dispersal and its role as a primary coloniser on fore dunes and beaches, that it probably occurred here naturally and was overlooked.   I reckon a preferable definition of a weed is an "an undesirable plant" and therefore from a birding perspective, there are not many weeds.

Regards
 

Ian May

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