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Description
It's late autumn in the town of Southpoint and this far south the chill of winter is already been felt, the suburbs turned white by a thin layer of snow that fell during the night. The morning is quiet as at this time of year most birds do not become active and begin calling until the sun has warmed them up sufficiently. However, the quiet rolling calls of two large birds reveal that at least one avian migrant is active at this hour. Flying with lazy wingbeats over the houses below is a pair of Highland Cockatoos, having just arrived from their summer feeding grounds in the mountains of the Central Highlands. The two cockatoos begin to descend as they look for a place to land, eventually wheeling into a large introduced pine tree and quickly sticking their beaks into the cones to feed. As the native trees that once covered these lowlands are cleared they have had to make do with whatever they can find, and these pines make as good of a substitute as any. The suburbs of Southpoint are where they will spend their winter in asylum from the even colder conditions at higher altitudes, before they make the journey back up into the mountains once warmer weather returns.

Highland Cockatoo
Australocacatua montanus

Classification: Psittaciformes, Cacatuoidea, Cacatuidae, Nymphicinae

Origins and evolutionary relationships: The fossil record of cockatoos is even more limited than that of other parrots, the earliest known being from the early Miocene of Riversleigh but given this was already a member of Cacatua it is likely the family originated significantly earlier. Two of the three subfamilies of cockatoos, Cacatuinae and Nymphicinae, occur in Tasmania, and while the former is by far the most diverse elsewhere here it is the Nymphicinae that dominates, being the most successful group of parrots on the island. Commonly known as the long-tailed cockatoos, their only representative elsewhere is the little Cockatiel of inland Australia and like that species many of the nymphicines here show greater resemblance to psittacoidean "true" parrots than to other cockatoos, formerly leading to confusion as to which group they are allied with. Such confusion is no problem in regards to the genus Australocacatua however, which contains species that have convergently evolved to resemble more typical cockatoos. The Highland Cockatoo is one of the most unique.

Description: The Highland Cockatoo, also known as the Great Grey Cockatoo, is the largest of Tasmania's parrots, just outsizing the Palm Cockatoo of New Guinea and Queensland and therefore being both the largest cockatoo and one of the largest parrots found anywhere on earth. In bodyplan they show great resemblance to a typical cockatoo, aside from the giveaway long tail of course. They are mostly covered in dull brownish-grey plumage with various markings in order to give them some degree of camouflage, which is important for a large bird that spends a significant amount of time on the ground as they are more vulnerable to predation than they would be otherwise. The beak is heavily hooked and extremely powerful, with the upper mandible being jet black while the lower is pale grey. Males and females differ little in size but can be told apart by the colour of the bare skin around their eyes, grey in the females and dirty yellow in the males. The crest is enormous, sleek and backswept, erecting when the bird is excited or frightened.

Habitat and distribution: These are migratory birds, spending their summer months among the mountains that run though the centre of the island and then making their way down into the lowlands during winter. Their summer feeding grounds largely consist of cold alpine moorland and subalpine woodland, but these are intelligent and crafty birds which allows them to exploit a wide variety of habitats when they retreat to the lowlands in the cooler months, everywhere from rainforest and grassland to farmland and city suburbs. They can be found across most of the island but are significantly more common in the south of their range.

Behaviour: While most cockatoos are loud and raucous birds, the Highland Cockatoo isn't. Most of their communication consists of soft rolling contact calls somewhat similar to those of black cockatoos but much quieter and subdued, although when they feel threatened they will give off a loud harsh screech like any other cockatoo which can be deafening at close range. Like the vast majority of parrots they are very social creatures and are almost never seen alone, commonly forming flocks of four to eight birds as they move between suitable foraging sites. Such groups are not permanent, but the bond between two cockatoos most certainly is. Highland Cockatoos mate for life and throughout their vast lifespans a pair will rarely ever leave each other's side, forming one of the strongest bonds known in the animal kingdom. So powerful is this bond that when one cockatoo dies the other often dies soon after, falling into a depressed state and starving after refusing to eat. This first became apparent when, during the early days of settlement, attempts were made to capture wild individuals to see how they would fair as pets, most dying from malnourishment within a month of their capture despite the best attempts to give them a wide ranging natural diet.

As can be expected from a parrot that has the capacity to have emotional trauma so strong it decides to starve to death, Highland Cockatoos are extremely intelligent and rank among the very smartest of birds. Their intelligence likely originated to allow them to best exploit the varied environments they occur in throughout the year, adapting their behaviour and foraging methods depending on the resources available and the habitat they are in. Their survival during winter also relies on cooperation between individuals sharing their past knowledge and the location of different resources, resulting in their highly developed emotional intelligence as well as a general sense of altruism. The use of sticks as tools is well documented both in controlled settings and in the wild, however it is not an ordinary part of their behaviour as their beak is usually flexible enough to make do. Their dietary preferences throughout the year are quite varied - generally their favoured food sources are nuts, seeds and fruits, however they will take what they can get during winter including fungi, worms, snails, grubs and even carrion, their powerful beaks just as effective at breaking open bones to reach the marrow within as they are at cracking nuts.

A pair of Highland Cockatoos will breed about once every two or three years, mating just before setting off for their summer feeding grounds. The mountains are not only plentiful in food during the warmer months, important for raising such large chicks, but also have less predators than lower altitudes, making them ideal nesting sites. Unfortunately there is a lack of large trees in these cool highlands, let alone suitable nesting hollows, and so the cockatoos have resorted to utilising secluded crevices, holes, small caves and unused burrows instead. They lay only a single egg, and the chick must develop fast in order to be ready to migrate once autumn sets in. Barely able to fly, the first migration is a tough ordeal for a young cockatoo as they fly hundreds of kilometres across unfamiliar terrain, but the support of their parents is usually enough for them to make it through. The chick will also make the return journey back up into the mountains with its parents before finally gaining independence once they reach the summer feeding grounds. Although their reproduction rate is extremely low they compensate for this with their longevity, with many wild individuals recorded as living for 80 years or more.

Conservation status and additional information: Highland Cockatoos have not seen any decline since European settlement and are therefore classed as Least Concern, although climate change has been identified as a long-term problem facing the species as it will likely result in the destruction of their summer feeding grounds and devastate the population. Climate Action Tasmania features a Highland Cockatoo on its logo for this reason.

For the speculative evolution project Van Diemen's Land Redux, see more here: specevo.jcink.net/index.php?sh…

Description
It's late autumn in the town of Southpoint and this far south the chill of winter is already been felt, the suburbs turned white by a thin layer of snow that fell during the night. The morning is quiet as at this time of year most birds do not become active and begin calling until the sun has warmed them up sufficiently. However, the quiet rolling calls of two large birds reveal that at least one avian migrant is active at this hour. Flying with lazy wingbeats over the houses below is a pair of Highland Cockatoos, having just arrived from their summer feeding grounds in the mountains of the Central Highlands. The two cockatoos begin to descend as they look for a place to land, eventually wheeling into a large introduced pine tree and quickly sticking their beaks into the cones to feed. As the native trees that once covered these lowlands are cleared they have had to make do with whatever they can find, and these pines make as good of a substitute as any. The suburbs of Southpoint are where they will spend their winter in asylum from the even colder conditions at higher altitudes, before they make the journey back up into the mountains once warmer weather returns.

Highland Cockatoo
Australocacatua montanus

Classification: Psittaciformes, Cacatuoidea, Cacatuidae, Nymphicinae

Origins and evolutionary relationships: The fossil record of cockatoos is even more limited than that of other parrots, the earliest known being from the early Miocene of Riversleigh but given this was already a member of Cacatua it is likely the family originated significantly earlier. Two of the three subfamilies of cockatoos, Cacatuinae and Nymphicinae, occur in Tasmania, and while the former is by far the most diverse elsewhere here it is the Nymphicinae that dominates, being the most successful group of parrots on the island. Commonly known as the long-tailed cockatoos, their only representative elsewhere is the little Cockatiel of inland Australia and like that species many of the nymphicines here show greater resemblance to psittacoidean "true" parrots than to other cockatoos, formerly leading to confusion as to which group they are allied with. Such confusion is no problem in regards to the genus Australocacatua however, which contains species that have convergently evolved to resemble more typical cockatoos. The Highland Cockatoo is one of the most unique.

Description: The Highland Cockatoo, also known as the Great Grey Cockatoo, is the largest of Tasmania's parrots, just outsizing the Palm Cockatoo of New Guinea and Queensland and therefore being both the largest cockatoo and one of the largest parrots found anywhere on earth. In bodyplan they show great resemblance to a typical cockatoo, aside from the giveaway long tail of course. They are mostly covered in dull brownish-grey plumage with various markings in order to give them some degree of camouflage, which is important for a large bird that spends a significant amount of time on the ground as they are more vulnerable to predation than they would be otherwise. The beak is heavily hooked and extremely powerful, with the upper mandible being jet black while the lower is pale grey. Males and females differ little in size but can be told apart by the colour of the bare skin around their eyes, grey in the females and dirty yellow in the males. The crest is enormous, sleek and backswept, erecting when the bird is excited or frightened.

Habitat and distribution: These are migratory birds, spending their summer months among the mountains that run though the centre of the island and then making their way down into the lowlands during winter. Their summer feeding grounds largely consist of cold alpine moorland and subalpine woodland, but these are intelligent and crafty birds which allows them to exploit a wide variety of habitats when they retreat to the lowlands in the cooler months, everywhere from rainforest and grassland to farmland and city suburbs. They can be found across most of the island but are significantly more common in the south of their range.

Behaviour: While most cockatoos are loud and raucous birds, the Highland Cockatoo isn't. Most of their communication consists of soft rolling contact calls somewhat similar to those of black cockatoos but much quieter and subdued, although when they feel threatened they will give off a loud harsh screech like any other cockatoo which can be deafening at close range. Like the vast majority of parrots they are very social creatures and are almost never seen alone, commonly forming flocks of four to eight birds as they move between suitable foraging sites. Such groups are not permanent, but the bond between two cockatoos most certainly is. Highland Cockatoos mate for life and throughout their vast lifespans a pair will rarely ever leave each other's side, forming one of the strongest bonds known in the animal kingdom. So powerful is this bond that when one cockatoo dies the other often dies soon after, falling into a depressed state and starving after refusing to eat. This first became apparent when, during the early days of settlement, attempts were made to capture wild individuals to see how they would fair as pets, most dying from malnourishment within a month of their capture despite the best attempts to give them a wide ranging natural diet.

As can be expected from a parrot that has the capacity to have emotional trauma so strong it decides to starve to death, Highland Cockatoos are extremely intelligent and rank among the very smartest of birds. Their intelligence likely originated to allow them to best exploit the varied environments they occur in throughout the year, adapting their behaviour and foraging methods depending on the resources available and the habitat they are in. Their survival during winter also relies on cooperation between individuals sharing their past knowledge and the location of different resources, resulting in their highly developed emotional intelligence as well as a general sense of altruism. The use of sticks as tools is well documented both in controlled settings and in the wild, however it is not an ordinary part of their behaviour as their beak is usually flexible enough to make do. Their dietary preferences throughout the year are quite varied - generally their favoured food sources are nuts, seeds and fruits, however they will take what they can get during winter including fungi, worms, snails, grubs and even carrion, their powerful beaks just as effective at breaking open bones to reach the marrow within as they are at cracking nuts.

A pair of Highland Cockatoos will breed about once every two or three years, mating just before setting off for their summer feeding grounds. The mountains are not only plentiful in food during the warmer months, important for raising such large chicks, but also have less predators than lower altitudes, making them ideal nesting sites. Unfortunately there is a lack of large trees in these cool highlands, let alone suitable nesting hollows, and so the cockatoos have resorted to utilising secluded crevices, holes, small caves and unused burrows instead. They lay only a single egg, and the chick must develop fast in order to be ready to migrate once autumn sets in. Barely able to fly, the first migration is a tough ordeal for a young cockatoo as they fly hundreds of kilometres across unfamiliar terrain, but the support of their parents is usually enough for them to make it through. The chick will also make the return journey back up into the mountains with its parents before finally gaining independence once they reach the summer feeding grounds. Although their reproduction rate is extremely low they compensate for this with their longevity, with many wild individuals recorded as living for 80 years or more.

Conservation status and additional information: Highland Cockatoos have not seen any decline since European settlement and are therefore classed as Least Concern, although climate change has been identified as a long-term problem facing the species as it will likely result in the destruction of their summer feeding grounds and devastate the population. Climate Action Tasmania features a Highland Cockatoo on its logo for this reason.

For the speculative evolution project Van Diemen's Land Redux, see more here: specevo.jcink.net/index.php?sh…