In Maianbar there is an over-abundance of parrots, Sulphur crested Cockatoos, Rainbow Lorikeets, King Parrots and the odd Little Corella and Crimson Rosella. These are the species that have learned to exploit the kinder nature of nature-loving people, they beg and steal and sing for food handouts. The birds are adaptable and will take seed or bread or fruit or any unattended pet food. Cockatoos will try almost anything, even flying off with a greasy bone. The nectar feeding lorikeets will take seed perhaps doing damage to the fine bristles on the tongue that would normally brush the nectar from flowers. The King parrots take the last place in line as they have none of the unruly aggression of the others, but since they have the most beautiful plumage and melodious song the people will see that they are fed.
Where food is plentiful there is overcrowding and competition for nesting hollows. An unhealthy diet and cramped living leads to disease and many of the cockatoos show the symptoms of beak and feather disease, where the feathers fall away and the beak elongates into an awkward hook. Young birds are particularly susceptible to the disease and are often evicted from the nest with the onset of disease. The cockatoos are relatively recent arrivals to the coast, they have come from the inland in a migration following the resources we have made available. Birds that are common in cities and suburbs and in the rural landscape are often there because of the food and shelter we provide. Like people, the birds that thrive in our suburbs are also colonists. Operating in large social groups these birds are able to set up a co-operative arrangement where competition from other species is squashed.
Early in the Maianbar morning before the dawn, about the time of the first Kookaburra call there is a high pitched soft piping chorus of birds calling. These are the Noisy Miners, a native bird that has spread with the suburban garden and the popularity of the sticky nursery trade grevillea flowers. During the day the Noisy Miners give voice to a wide range of calls, keeping a buzzing social scene that is more about alarm than attraction. Other small birds are commonly chased out of the gardens, and the miners are given to violent territorial squabbles between themselves.
Each of these birds adapted to suburban life has a similar cousin who remains in the wild. The brash white Sulphur crested Cockatoo has a shy black twin, the Yellow tailed black Cockatoo, a bird that is less ebuliant and almost secretive. The Rainbow Lorikeet has perhaps taken the place of the Eastern Rosella a bird that was once common while suburban developments still had outskirts of scrub and meadows of seed bearing grasses. The Noisy Miner has interestingly pushed ahead of the introduced Indian Mynah that was once dominant in the Sydney suburbs. The Bell Miner is also on the upsurge and is thought to be responsible for the spread of Eucalypt die-back, through its displacement of pest controlling bird species.
One other pair of songbirds that should be more common inside the suburban setting of Maianbar is the Superb Fairy-wren and the Variegated Fairy-wren. These birds do well when a little of the low shrub lawyer is left intact and cats are not free-ranging. In these birds the family group work together as a small tribe eating insects. In both species all the birds are drab except for the adult males which stand out with an electric blue cap, nape and cheeks. In the Variegated Fairy-wren the blue of the mature male is augmented with little chestnut shoulders. The calls of both species are also very similar in structure but they are noticeably different.
And now for the racism. Birds of the the same species, that is birds that are able to produce fertile offspring, are often separated geographically, by a barrier or an area of unsuitable terrain, and since the separated groups are not interbreeding they develop slight genetic or cultural differences. These diverging groups are described as different races of the same species. Over time the drift in the differences between separated populations may ultimately lead to the development of separate species. One of the key drivers of this separation is the development of bird calls, a cultural shift that leads to speciation through sexual selection. There is a natural diversity in the song patterns that may be inherited, but song is also coloured by mimicry. Other birds may lend elements to the repertoire. The attraction of a newly developed call replaces the attraction of the old call. And so it is that the choice of a suitable candidate for reproduction is linked to the development of noisy racist tweets.
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