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Description
It is morning in the remote forests of southern Tasmania. As the sun rises and the cold morning mist begins to clear, the forest comes alive with all sorts of birds, reptiles, frogs and insects, all making an early start to get the most out of the new day. However, the morning light also reveals a grim sight. Several metres above the ground lies the mangled, half-eaten corpse of a rangatooth, wedged into a tree fork for all to see. Its head, tail and limbs remain intact but its torso and abdomen has been ripped open and eaten out. What sort of nocturnal killer could be responsible for this gruesome scene?

Black Nightfisher
Nyctophoneus obscurus

Classification: Coraciiformes, Alcedinidae, Nyctophoninae

Origins and evolutionary relationships: At the time Tasmania split off from Australia, there were no owls, and to this day, not a single strigiforme has set foot on the island. In their absence, another group of predatory birds have taken their place; the kingfishers. These arrived in Australia sometime in the first half of the Miocene, and managed to be blown over to Tasmania before it became too far from the mainland. Here in isolation, they began to take advantage of the large variety of small creatures that only came out at night, evolving large eyes, excellent hearing and silent flight, all to help them track down and capture prey under the cover of darkness. These became the nightfishers, Tasmania's dominant nocturnal predatory birds. Several different species of nightfisher occur across the island, but undoubtedly the most fearsome is the Black Nightfisher.

Description: The Black Nightfisher is the largest species of nightfisher. It grows noticeably larger than the introduced Laughing Kookaburra, which also makes it the largest kingfisher on earth. It is the only nightfisher with fully black plumage, which makes identification from its relatives easy. The dark plumage that completely covers its body makes any other colours stand out, as shown by the blood red beak and the huge piercing yellow eyes. Rings of feathers around the eyes acts like the facial disk of owls, funnelling sound towards the ears. However, both ears are symmetrical, unlike the asymmetrical ears of owls. The feet and legs are larger than those of other kingfishers, adapted for gripping prey. When a light is shone in their eyes they give off bright red eyeshine.

Habitat and distribution: This large species is only found in the pristine primary rainforest in the south of the island, away from people. It requires tall trees, some of which must be old enough to provide large tree hollows. They have a naturally low population density.

Behaviour: Exclusively nocturnal, they spend their days within one of several tree hollows within their territory, taking shelter from the sun and diurnal predators. Once darkness falls they emerge from their lairs, and, after stopping for a few minutes to preen their feathers and survey the area for potential threats, they set off to begin hunting.

Black Nightfishers prey on a variety of small animals, including large arthropods, lizards, snakes, frogs, sleeping birds, and small to medium-sized mammals. As such it has a wide variety of hunting styles, including flying slowly through the forest, climbing through the trees, stalking on the ground and even chasing bats through the skies, but its favourite strategy is to perch on an exposed branch a few metres above the forest floor and wait for prey to appear in typical kingfisher fashion. Once suitable prey is spotted, it will fly silently above its target, and then swoop down onto its quarry. An animal small enough to be held in the beak will be carried back to the perch to be killed and consumed, while a larger animal must be killed first using their powerful beak, before being carried back to the perch in their talons to be dismembered and consumed. Often, cracticine style, they will wedge large prey in a tree fork for easy dismemberment, and the gruesome sight of mangled hanging corpses left to rot once the bird has eaten its fill is a sure sign that a Black Nightfisher is about.

Black Nighfishers are highly territorial, and an individual or pair of birds require a territory of several square kilometres, with enough prey to sustain them and several suitable hollows for resting and nesting. If another nightfisher enters their territory, it is quickly chased off. In order to announce their territory they make raucous, cacophonous calls consisting of accented hoots, trills, cackles and constant downwards and upwards pitches, which can travel for many kilometres through the forest. The call is quite unique and haunting, and has inspired many legends of horrible nocturnal monsters that shout out in the night.

Although some nightfishers remain solitary for their entire lives, those that do find a partner they mate for life and share the same territory, although they forage alone. They breed during spring and summer, and the 2-3 young are extremely demanding and must be fed by both parents constantly throughout the night. Once they are three quarters of their full size they are chased out of their parents territory. What happens to the young after this and how they establish their own territories is unstudied for now and the subject of future research.

Conservation status and additional information: This species would be threatened by habitat destruction, but luckily its entire range is remote, fairly untouched and within the Gondwana World Heritage Area, and therefore the species is under no threat. Several aspects of their behaviour are unknown because they are hard to study in their remote habitat.

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

Description
It is morning in the remote forests of southern Tasmania. As the sun rises and the cold morning mist begins to clear, the forest comes alive with all sorts of birds, reptiles, frogs and insects, all making an early start to get the most out of the new day. However, the morning light also reveals a grim sight. Several metres above the ground lies the mangled, half-eaten corpse of a rangatooth, wedged into a tree fork for all to see. Its head, tail and limbs remain intact but its torso and abdomen has been ripped open and eaten out. What sort of nocturnal killer could be responsible for this gruesome scene?

Black Nightfisher
Nyctophoneus obscurus

Classification: Coraciiformes, Alcedinidae, Nyctophoninae

Origins and evolutionary relationships: At the time Tasmania split off from Australia, there were no owls, and to this day, not a single strigiforme has set foot on the island. In their absence, another group of predatory birds have taken their place; the kingfishers. These arrived in Australia sometime in the first half of the Miocene, and managed to be blown over to Tasmania before it became too far from the mainland. Here in isolation, they began to take advantage of the large variety of small creatures that only came out at night, evolving large eyes, excellent hearing and silent flight, all to help them track down and capture prey under the cover of darkness. These became the nightfishers, Tasmania's dominant nocturnal predatory birds. Several different species of nightfisher occur across the island, but undoubtedly the most fearsome is the Black Nightfisher.

Description: The Black Nightfisher is the largest species of nightfisher. It grows noticeably larger than the introduced Laughing Kookaburra, which also makes it the largest kingfisher on earth. It is the only nightfisher with fully black plumage, which makes identification from its relatives easy. The dark plumage that completely covers its body makes any other colours stand out, as shown by the blood red beak and the huge piercing yellow eyes. Rings of feathers around the eyes acts like the facial disk of owls, funnelling sound towards the ears. However, both ears are symmetrical, unlike the asymmetrical ears of owls. The feet and legs are larger than those of other kingfishers, adapted for gripping prey. When a light is shone in their eyes they give off bright red eyeshine.

Habitat and distribution: This large species is only found in the pristine primary rainforest in the south of the island, away from people. It requires tall trees, some of which must be old enough to provide large tree hollows. They have a naturally low population density.

Behaviour: Exclusively nocturnal, they spend their days within one of several tree hollows within their territory, taking shelter from the sun and diurnal predators. Once darkness falls they emerge from their lairs, and, after stopping for a few minutes to preen their feathers and survey the area for potential threats, they set off to begin hunting.

Black Nightfishers prey on a variety of small animals, including large arthropods, lizards, snakes, frogs, sleeping birds, and small to medium-sized mammals. As such it has a wide variety of hunting styles, including flying slowly through the forest, climbing through the trees, stalking on the ground and even chasing bats through the skies, but its favourite strategy is to perch on an exposed branch a few metres above the forest floor and wait for prey to appear in typical kingfisher fashion. Once suitable prey is spotted, it will fly silently above its target, and then swoop down onto its quarry. An animal small enough to be held in the beak will be carried back to the perch to be killed and consumed, while a larger animal must be killed first using their powerful beak, before being carried back to the perch in their talons to be dismembered and consumed. Often, cracticine style, they will wedge large prey in a tree fork for easy dismemberment, and the gruesome sight of mangled hanging corpses left to rot once the bird has eaten its fill is a sure sign that a Black Nightfisher is about.

Black Nighfishers are highly territorial, and an individual or pair of birds require a territory of several square kilometres, with enough prey to sustain them and several suitable hollows for resting and nesting. If another nightfisher enters their territory, it is quickly chased off. In order to announce their territory they make raucous, cacophonous calls consisting of accented hoots, trills, cackles and constant downwards and upwards pitches, which can travel for many kilometres through the forest. The call is quite unique and haunting, and has inspired many legends of horrible nocturnal monsters that shout out in the night.

Although some nightfishers remain solitary for their entire lives, those that do find a partner they mate for life and share the same territory, although they forage alone. They breed during spring and summer, and the 2-3 young are extremely demanding and must be fed by both parents constantly throughout the night. Once they are three quarters of their full size they are chased out of their parents territory. What happens to the young after this and how they establish their own territories is unstudied for now and the subject of future research.

Conservation status and additional information: This species would be threatened by habitat destruction, but luckily its entire range is remote, fairly untouched and within the Gondwana World Heritage Area, and therefore the species is under no threat. Several aspects of their behaviour are unknown because they are hard to study in their remote habitat.

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