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.

IMG_0275

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

Why are old trees so important?

Many animals use trees for habitat in Australia, with animals from all major fauna groups solely depending on them for shelter, refuge and food. Possums eat Eucalyptus leaves while birds, flying foxes and small tree-dwelling mammals feed off flower nectar of many different tree species. Trees provide shelter via hollows, which are an essential habitat feature for birds, arboreal mammals, frogs and some tree dwelling snake species. Some hollows even naturally store water which has been shown to be important drinking sources for Feather-tailed Gliders and tree frogs. Some tree species found locally around Sydney, such as the Smooth-barked Apple (Angophora costata) and the Blackbutt (Eucalyptus pilularis) are able to produce large hollows which are essential nest habitat for the Powerful Owls (Ninox strenua).

 

Australian Owlet Nightjar (Aegotheles cristatus): A bird which is entirely dependent on tree hollows for shelter | Copyright Chad Beranek 2016

Australian Owlet Nightjar (Aegotheles cristatus): A bird which is entirely dependent on tree hollows for shelter | Copyright Chad Beranek 2016

 

So where does tree age come into the picture? Tree age is important as for hollows to form a tree must be very mature. The age at which hollows to naturally form varies among tree species. For example, Blackbutt hollows start forming around 100 years old. At 140 years of age, the average Blackbutt will have numerous smaller sized hollows which are usable for small mammals and birds. For larger hollows to develop to accommodate larger animals, a Blackbutt will need to reach an age of around 210 years of age.

 

Sugar Glider (Petaurus breviceps): Require old growth trees for shelter | Copyright Chad Beranek 2015

Sugar Glider (Petaurus breviceps): Require old growth trees for shelter | Copyright Chad Beranek 2015

 

The process that occurs for hollows to form is one of natures many fascinating processes. Firstly a tree must receive some kind of damage, which occurs naturally from twigs or branches breaking off. This unprotected scar then becomes infected by fungus which proceeds to rot the wood. This fungal infection enables easy access for termites which then make a nest in the rotting wood and feast on the fungus and the lignin in the wood. Once termites have established a nest, loose bits of the wood and termite nest will dislodge and thus form a hollow. Once again it must be remembered that this process cannot happen over night and requires decades to create viable habitat hollows.

 

 

Now given all these facts, it really puts perspective on current law practices which involve trees. Given how vitally important old growth hollow bearing trees are to a huge amount of different species, including many threatened species, why does the law make it so easy for trees to be cut down? While some trees may be a hazard for property, many of these laws are being abused just so a property owner can get better water views in attempt to get better property value.

 

A stand of Blackbutt (Eucalyptus pilularis) coexisting fine in suburbia | Copyright Chad Beranek 2015

A stand of Blackbutt (Eucalyptus pilularis) coexisting fine in suburbia | Copyright Chad Beranek 2015

 

In conclusion, we must pay respect to trees and pay even more respect to elderly trees! Instead of cutting older trees down to mitigate potential property damage, first seek other potential options, such as pruning more hazardous branches, leaving the tree to stand. Also be on the lookout for illegal tree lopping which is becoming a bigger occurrence these days with our out of control property market.

At the moment, there are hundreds of trees threatened to be cut down in Centennial Park. Heritage listed figs which line the streets are at risk of the new light rail that is proprosed. To find out how you can make a difference please visit Saving Sydneys Trees, and attend the protest on the 1st of May!