Secretive Snakes – The Rare and Illusive Hoplocephalus

In Australia, most venomous front fanged (Elapid) snakes are ground dwelling. When one thinks about Australian snakes, its most often the formidable terrestrial snakes come to mind, such as the Eastern Brown Snake (Pseudonaja textilus) or the elegant and streamlined Red-bellied Black Snake (Pseudechis porphyriacus). However there is an arboreal (tree-climbing) group of elapid snakes present in the Australia bush which are less well known, and much less seen. These snakes are collectively in the Hoplocephalus genus and have been the focus of scientific intrigue, due to their individualistic ecological habits. There are three of these peculiar but fascinating serpents; Broad-headed Snake, Pale-headed Snake and Stephen’s Banded Snake. In this article we shall briefly go over each species peculiarities.

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The Broad-headed Snake (Hoplocephalus bungaroides)

The Broad-headed Snake is considered the king of Sydney sandstone rock escarpments. Found in open woodland on west facing slopes, this snake species feeds primarily on geckos and skinks which cohabitant the same craggy sand rock shelves. This snake primarily has been the focus of much research coming out of the University of Sydney, which has uncovered a very fascinating life history. It appears that during winter this snake will take shelter under rocks and in cliff crevices, and in summer it will pursue a life climbing trees. It chooses western facing rock slopes when sheltering preferentially due to its nocturnal nature. This is because western facing rock slopes will get sun light as the sun is setting which will warm up the Broad-headed Snake and give it energy before it goes forth that night hunting.

Broad-headed Snake (Hoplocephalus bungaroides) | Copyright Chad Beranek 2016

Broad-headed Snake (Hoplocephalus bungaroides) | Copyright Chad Beranek 2016

Broad-headed Snakes have anecdotally been confused for baby Diamond Python in the past. This is a deadly mistake to make. Thus far there has been a reported fatality from a Broad-headed Snake bite which was likely due to allergy to the venom. Broad-headed Snake venom can cause local pain, swelling, and severe drops in blood pressure causing dizziness and fainting.  This risks possible death. If you see a Broad-head out at night do not pick it up. They are a very agile and defensive snake species which is hard to contain.

One of the Broad-headed Snakes main food items: Lesueur's Velvet Gecko (Amalosia lesueurii) | Copyright Chad Beranek 2016

One of the Broad-headed Snakes main food items: Lesueur’s Velvet Gecko (Amalosia lesueurii) | Copyright Chad Beranek 2016

The Pale-headed Snake (Hoplocephalus bitorquatus)

The Pale-headed Snake is a tree dwelling assassin which spends much of its time living within the canopy, nestled in tree hollows and under bark exfoliation of River Red Gums and Coolabahs. Their distribution extends from NNSW right into QLD where their preferred habitat trees are most prevalent. They are rarely found far from a water course as their primary food is frogs, whom they ambush at night with silent stealthy strikes. Due to being found in areas which are most often far away from human habitance, this is the least known Hoplocephalus.

Pale-headed Snake (Hoplocephalus bitorquatus) | Copyright Stephen Mahony 2015

Pale-headed Snake (Hoplocephalus bitorquatus) | Copyright Stephen Mahony 2015

Stephen’s Banded Snake (Hoplocephalus stephensii)

Stephen’s Banded Snakes are considered more of a rainforest dweller out of the trio. This snake prefers its own company and will shelter in solitude in tree hollows high up in the moist canopy for extended periods of time. After lying in wait they descend to the forest floor and can travel over a hundred meters in search of prey and mates. They will explore alternative tree hollows in hopes of finding a nesting mammal such as a Pigmy Possum, Feather-tailed Glider or a Bush Rat. If the resident is home, the snake will strike immediately, if not, the snake will lie in wait of the resident to return home and then strike. In either scenario the unwelcome guest will devour the occupant and sleep in the occupants nest while the occupant digests.

Stephens Banded Snake (Hoplocephalus stephensii) | Copyright Chad Beranek 2016

Stephens Banded Snake (Hoplocephalus stephensii) | Copyright Chad Beranek 2016

What is common with all these snakes? They all have curious habitat requirements which makes them all vulnerable to population declines. The Broad-headed Snake is often poached and have their habitat destroyed by reptile collectors, and much of their habitat has been built on as the of their core distribution lies in the Sydney region. The Pale-headed Snake is threatened by tree removal and habitat destruction in areas dominated by farm developments. Due to the large home range and tree hollow usage of the Stephen’s Banded Snake, this snake species cannot exist in fragmented landscapes and requires expansive tracts of forests. All of these snakes are almost entirely eliminated with development as they depend on trees. Trees are vitally important for a host of animals.




For ways you can help save trees, especially in Sydney, please visit: Saving Sydneys Trees

King of the Sandstone Throne: The red crowned toadlet

This species of the week is dedicated to the threatened red crowned toadlet (Pseudophryne australis) which is both spectacularly adorable and has an incredibly interesting strategy of survival. This frog is quite small and is really strange for a frog in the way it lives. The red crowned toadlet, unlike most frogs, makes a terrestrial nest. The male will sit and guide his egg clutch and call almost all year round. Female red crowned toadlets visit the male and deposit eggs which he fertilises. The tadpoles start development inside the egg. A male will end up with eggs of many different stages of development stages. When it rains, the eggs in the nest will wash away to the closest puddle or creek where the developed tadpoles will emerge from their eggs to complete development as free swimming tadpole. Only the eggs at the right development stage will be able to survive when being washed into a puddle.  By having eggs of multiple development stages, the red crowned toadlet is able to ensure at least some of the eggs will be at the correct development stage when it rains and will hatch. This is the unique strategy of the red crowned toadlet known as ‘bet hedging’.

 

Copyright Chad Beranek (2014)

Copyright Chad Beranek (2014)

 

The red crowned toadlet is found in sandstone areas across Sydney and is quite well distributed within the Royal National Park. They prefer rocky sandstone outcrops and reside within tributaries that are prone to drying up. This is the perfect habitat for their unique life strategy. They are threatened due to being easily wiped out during development and may be susceptible to the changes to water run off due to curb and guttering, which diverts water away from the small tributaries that the red crowned toadlets live in.   With good management, this species can be preserved and hopefully they will continue to exist unimpeded in areas such as the Royal National Park as they are an interesting little frog.

 

A male Red Crowned Toadlet next to his nest of eggs | Copyright Lucy Kidson (2014)

A male Red Crowned Toadlet next to his nest of eggs | Copyright Lucy Kidson (2014)

 

One last random fact sure to interest most people is you can actually talk to them and they will call back. They are able to hear the frequency of the human voice, and if you yell for example “HEY FROG!?”, it will respond in its calls which is a series of squelches and squeaks.

 

Male Red Crowned Toadlet | Copyright Lucy Kidson (2014)

Male Red Crowned Toadlet | Copyright Lucy Kidson (2014)