HOW TO MAKE YOUR PROPERTY SNAKE UN-FRIENDLY|
Increasingly property owners around Australia are realizing the value of our bio-diversity. They are aware of problems with salinity, the demise of some of our frogs, and the need for suitable habitats for all our wildlife.
Around the cities most people attempt to make improvements for local birds, mammals and frogs. Unfortunately, some of the most common reptiles inhabit virtually all capital cities of Australia.
SNAKES IN SUBURBIA
Australia has about 863 species of reptiles including 188 species of snakes (Cogger 2000). Only 14% of these snakes are regarded as potentially dangerous to humans (White et al 1998). Some species of venomous snakes have adapted positively to changes in the natural environment and are now common in many of the suburban areas of south eastern Australia. The Eastern Brown Snake (Pseudonaja textilis) has been most successful in this regard. Overgrown gardens, unkempt public reserves, junky industrial areas or just properties which need a "post-winter" clean up (with their attendant rodents) are all home to Brown Snakes.
WHAT YOU SHOULD BE AWARE OF
Snakes are normally secretive and timid animals. Brown Snakes are able to hide in the most unlikely places including under wood, tin, old lino, concrete slabs, plastic, and roof tiles on the ground; within piles of bricks, pipes, fire wood and stones; inside sheds, shops and houses; in the cavities of walls; in aviaries; and even in swimming pools (personal observation).
Many gardeners, who go to the trouble of making their property more livable for themselves, and our native wildlife, don't realize how readily they have also made their gardens acceptable to snakes. The following specific comments may help you understand the potential problems.
ROCKERIES, RETAINING WALLS, DRY STONE WALLS
Unless the components of your rock feature are imbedded into the soil and all gaps between the rocks or blocks packed tightly with soil, there will be numerous cracks, crevices and holes for snakes to hide in or to follow their prey(lizards, frogs or mice). You do not always have to remove the rocks, as quarry rubble or dolomite can be spread amongst and through the rocks or blocks. Then water and tamp it down hard so the areas between can no longer be used by snakes and to a lesser extent mice. Brown Snakes do not generally dig their own holes, unless the soil is very sandy. They much prefer to utilise existing tunnels made by other animals, or crevices made through the action of water or cracking clays etc. "Pockets" can be provided so that you can still plant trailing plants or rockery species without having a bare, stone feature (as long as you are aware of the following points also).
PLANTING AROUND THE GARDEN
Many of the calls which snake catchers throughout Australia receive, involve snakes that are seen in or close to thick vegetation somewhere in the garden. The problem here is more likely dense groundcovers or plants growing close to the ground which provide excellent protection for snakes. Recent studies (Whitaker and Shine, 1999) have shown that Brown Snakes when hiding in thick cover do not move when approached by a human. That can be to your advantage as the snake is unlikely to respond to your presence, and will move away when the "threat" (you)to it has passed. However, young inquisitive children and pets that actually probe innocently into the plants may evoke a different response. Whitaker and Shine found that less than 3% of Brown Snakes (from 455 encounters) approached ("attacked") the researchers during their study.
The solution to an overgrown garden is not necessarily ripping the lot out. Shrubs can have their lower branches pruned to allow you to readily see beneath them and provide less suitable cover for snakes. But a thick blanket of ivy around an older garden may be difficult to justify removing. A compromise may be to thin the groundcover so that you can at least see if a snake is moving through it. By reducing the level of cover you are also denying protection for roaming snakes.
COMPOST HEAPS, BINS
When we adopt a recycling attitude that includes disposal on site of our kitchen and garden wastes, we are providing two essentials for Brown Snakes in particular: shelter and food for the snake's prey, as well as protection for the snake from its enemies. In addition, there is the chance that the warmth and humidity of a compost heap may be suitable for a female Brown Snake to lay her eggs (between 12 and 40 depending on the size of the snake). The placing of the compost can create problems too, as there may be little traffic in that part of the garden, which is ideal for a wandering snake. An enclosed, tumbling compost bin is the best answer to this problem. Turning over the compost regularly is another. To prevent rodents and snakes moving up into a bottomless compost bin, place it on a square of 10mm steel mesh (but you will have to renew it periodically as it rusts). The mesh allows movement of air, water and soil organisms but not undesirables.
MOVEMENT INTO SHEDS, GARAGES, OTHER BUILDINGS
Interpretation of snake callout data in Adelaide in the mid 1990s indicated that about 11% of snakes seen were inside buildings, including houses, sheds, factories, schools, shops or offices. Generally the altercations with humans did not result in damage to either side, but the situation is obviously potentially dangerous. The simple answer is to stop access by adult snakes under closed exterior doors (including screen doors). This can be done inexpensively by fitting a rubber weather seal to the bottom of the door(s) of all buildings that may be affected. Be aware that a sizeable (up to 1.2m) Brown Snake is able to squeeze under a gap or into a hole not much bigger than your thumb.
If you have exterior wall vents at ground level on your buildings, you can also prevent entry by small snakes (and bees, wasps, mice etc) by fixing a piece of metal flywire over each vent. Keep any planting around the house rather spartan, or at least not adjacent to the walls. Black (Pseudechis spp) and Tiger Snakes (Notechis spp) can climb quite well - and so can Brown Snakes when they have to - especially with the help of thick vegetation over trellises near buildings.
Snakes will not normally live under houses, if there is a substantial gap between the floorboards and the soil. Unless, of course, you have stored your junk, building rubble, heaps of wood, unwanted furniture, toys or tools underneath. The answer here is obvious, but necessary.
Forget the "infallible" solutions for keeping snakes away from your house environs or to trap them. Most do not work. A wine flagon on its side containing a drop of red; a bowl of milk laced with ratsack; a layer of diesel spread as a barrier on the ground; or collecting/encouraging Blue Tongued and Shingleback Lizards on your property to discourage snakes are all fallacies.
Trapping snakes does sometimes work, but there are ethical considerations about even a venomous snake caught out in the hot sun. And there are the public health issues if a child or pet comes into contact with such a trapped snake.
Snakes are given some form of legal protection throughout Australia. If you are unsure of the status of snakes where you live, contact your state or territory fauna agency (check your local telephone directory or the internet) for advice.
Snakes shed their skin approximately every eight weeks, depending on how much food they have.
Some snakes can travel faster in a short distance than a human can.
A snake has a forked tongue where legless lizards have a single broad, fleshy tongue.
Snakes are not cold and slimy, they are smooth and silky to feel and they receive their heat from the elements.
If you are thinking of going swimming in the outback, remember ALL snakes can swim exceptionally well.
LIZARDS DON'T KEEP SNAKES AWAY, they are a food source to snakes.
ECOLOGY OF LARGE VENOMOUS SNAKES OF THE ADELAIDE REGION
Pygmy Copperhead, Austrelaps labialis
A highly venomous snake, but it has an unaggressive nature and rarely bites humans.
Habitat: Dry sclerophyll forest and woodland, in the vicinity of dense shrubby understory (often heath with tussock grasses), associated with seepage areas, watercourses and gullies.
Micro-habitat: Shelters in deep matted vegetation, especially tussock grasses, under flat stones and in, or under, fallen timber.
Food: Skinks and frogs are the main items of diet.
Black Tiger Snake, Notechis ater
Habitat: Gullies and valleys in the ranges, with more or less permanently watered creeks for most of the year. Vegetation of riverside open forest and woodland with shrubby or dense tussocky understory.
Micro-habitat: Shelters under large rocks and fallen rotten timber; in dense tussocky vegetation, especially near water; and in disused animal burrows.
Food: Frogs, lizards, small mammals, nestling birds, and tadpoles.
(Note: There is no published information on the population of Black Tiger Snakes in the Onkaparinga River valley.)
Eastern Tiger Snake, Notechis scutatus
Habitat: Cool to warm temperate permanent swamps, watercourses and seepages on valleys of the Murray River and its tributaries. Vegetation of dry and wet sclerophyll forest, woodland, shrubland including heath and tussock grassland.
Micro-habitat: Shelters in or under fallen rotting timber; under rocks; in dense, deep, matted vegetation; and in disused animal burrows.
Food: Frogs, lizards, nestling birds, and small mammals. Also fish and tadpoles.
Red-bellied Black Snake, Pseudechis porphyriacus
This stunning snake rarely causes serious harm and does not deserve the attacks humans make upon it. The venom is far less toxic than any of the common dangerous Australian snakes. Give these snakes space and the respect they need.
Habitat: Temperate slopes, ranges and lowlands in the vicinity of permanent watercourses, swamps and lakes. Vegetation of all forest types (closed, wet, dry) sclerophyll woodland and shrubland, including heath.
Micro-habitat: Shelters in dense vegetation, in hollow logs, in disused animal burrows, and under large flat rocks.
Food: Mostly frogs, but also lizards, occasionally mammals, snakes and fish.
Eastern Brown Snake, Pseudonaja textilis
Habitat: Eastern non-arid areas: all habitats except rainforest and alpine areas. Particularly common in partly cleared and cleared agricultural lands.
Micro-habitat: Shelters under, and in, fallen logs; in rock crevices; in disused animal burrows; in deep soil cracks; under large rocks; and under building rubbish around farms barns, settlements, towns and outlying suburbs. Unlike the Tiger Snake it prefers dry country to swampy areas.
Food: Small mammals, skinks, dragon lizards geckos rats, mice and other snakes. When available will eat frogs and birds.
Reference: Ehmann, H.F.W., 1992. Encyclopedia of Australian Animals. Reptiles. Angus & Robertson.
Check also: Wilson, S.K. & Knowles, D.G., 1988. Australia's Reptiles. A Photographic Reference to the Terrestrial Reptiles of Australia. Collins Publishers Australia.
Hoser, R.T. 1989. Australian Reptiles & Frogs. Pierson & Co.
INTERACTIONS BETWEEN HUMANS AND EASTERN BROWN SNAKES (Pseudonaja textilis: Elapidae)
The most frequent cause of serious snake bite in Australia after the Mainland Tiger Snake is the Common Brown Snake. Common Brown Snakes differ from other dangerous snakes as they are only active during the day except when the weather is extremely hot.
"An agitated Common Brown Snake is extremely dangerous with a ferocious temper and a propensity to aggressively defend itself" (Williams, 1999)
The Eastern Brown Snake is a very common venomous snake of eastern and southern Australia. It is variable in colour, being almost any shade of brown (Cogger, 2000). An Adelaide specimen has been found that is coloured blue-grey (personal observation). The Brown Snake has a slender streamlined body and the head is not distinct.
A Common Perception
Analysis of scientific and popular literature between 1964 and 2000 describes the temperament of Eastern Brown Snakes as: "pugnacious" (Gow, 1982), "very aggressive" (Kinghorn, 1964), "strikes savagely" (Queensland Museum, 1995), "vicious manner"(Waite, 1993), "easily aroused" (Worrell, 1970).
Two papers by Whitaker & Shine (1999) examined "Responses of free-ranging brown snakes to encounters with humans", and "When, where and why do people encounter Australian Brown Snakes?"
Over three years the researchers tracked and studied 40 telemetered snakes, and had opportunistic encounters with non-telemetered animals, 455 times in the study area of New South Wales.
1/ Free-ranging Brown Snakes do not usually attack people - snakes moved towards the researchers in less than 3% of the snakes studied;
2/ Provided actual contact was not made with the snake, it could be approached slowly and quite closely without attacking;
3/ Higher temperatures and the smaller size of snakes were two factors when they would flee an approaching human;
4/ Snakes were more likely to remain still at lower temperatures and when there was cloud cover;
5/ Brown Snakes rely heavily on crypsis when hiding in thick vegetation to escape detection;
6/ They responded "offensively" when there was less than 20% vegetation cover.
How to avoid Brown Snakes
The researchers found Brown Snakes to be reasonably predictable.
To lessen the risk of a confrontation:
A/ Move carefully, be observant and wear dark clothing;
B/ Keep away from natural areas on cool days in the spring - you are less likely to contact a courting snake;
C/ On cool, cloudy days that are windy, be especially vigilant as snakes may not perceive your presence;
D/ In areas where Brown Snakes might seek refuge, avoid them between late morning and mid-afternoon, particularly spring-time;
E/ The greatest danger with Brown Snakes is spring-time, if they are exposed, and suddenly approached and touched;
F If under cover and not interfered with, they tend to ignore a person even if trodden upon!
More appropriate terminology
Shine & Whitaker's studies point to Brown Snakes actually being wary, secretive and nervous reptiles that will defend themselves under certain conditions.
They state: "Overall, our findings belie this animal's reputation for 'aggression'. Instead, eastern brown snakes are very wary of people and avoid them whenever they can." (Whitaker & Shine, 1999)
Cogger, H.G. (2000). The Reptiles & Amphibians of Australia. Reed New Holland.
Gow, G.F. (1982). Australia's Dangerous Snakes. Angus & Robertson.
Kinghorn, J.R. (1964). The Snakes of Australia. Angus & Robertson.
Queensland Museum, (1995). Wildlife of Greater Brisbane. Queensland Museum & Brisbane City Council.
Waite, E.R. (1993). The Reptiles and Amphibians of South Australia. Society for the Study of Amphibians and Reptiles.
Williams, D. (1999). Common Brown Snake Pseudonaja textilis. Black Knight Reptiles. [Online] Available: http://www.kingsnake.com/aho/pseudonaja1.html [October 10, 2000]
Whitaker, P.B. & Shine, R. (1999). When, where and why do people encounter Australian brown snakes (Pseudonaja textilis: Elapidae)? Wildlife Research 26: 675 - 688.
Whitaker, P.B. & Shine, R. (1999). Responses of free-ranging brown snakes (Pseudonaja textilis: Elapidae) to encounters with humans. Wildlife Research 26: 689 - 704.
Worrell, E. (1970). Reptiles of Australia. Angus & Robertson.
There is an abundance of information about snakes available, but how much of it is accurate or reliable? Whether you access information from the internet, magazines or other printed references, determine that it comes from a reputable source. If the publisher is a government body (eg state museum, national parks or environment department) or a medical or tertiary institution, or is affiliated with such an organisation, then you should be able to accept it as worthy of your attention. Be wary especially of websites from overseas which may not relate to Australian conditions or our snake fauna.
Cogger, H.G. (2000). Reptiles & Amphibians of Australia. Reed New Holland.
Whitaker, P.B. & Shine, R. (1999). When, where and why do people encounter Australian brownsnakes (Pseudonaja textilis:Elapidae)? Wildlife Research 26: 675-688.
Whitaker, P.B. & Shine, R. (1999). Responses of free-ranging brownsnakes to encounters with humans. Wildlife Research 26: 689-704.
White, J., Edmonds, C. & Zborowski, P (1998). Australia's Most Dangerous spiders, snakes and marine creatures. Australian Geographic.
LIVING WITH WILDLIFE
Living with Wildlife has been conducting professional training courses for state and territory fauna agencies, industry, local government and others since 1993, with over 1000 people trained throughout Australasia to deal with venomous snakes. Courses to keep previous participants up to date and with a high level of skill are also available.
For advice in any situation Australia-wide when snakes are perceived to be a problem, professional help is available for local government, industry, government departments and private property owners.
Living with Wildlife can be contacted by mail to: P.O. Box 707, BLACKWOOD, South Australia 5051; e-mail: firstname.lastname@example.org ;or by telephone: (08) 81780344 or mobile 0408838034.
Copyright Living with Wildlife 2001.
Content may be reproduced with appropriate acknowledgment.
SNAKES IN YOUR GARDEN
Most capital cities of Australia have organised groups or businesses that will respond to property owners' concerns about the presence of a snake. In some states or regional centres, staff of the government fauna agency may attend or offer advice.
The cost of a callout by a private operator can vary considerably from one place to another, and even within the same city. Some herpetologists from a reptile society may be willing to attend for a nominal charge. Ask your state museum or fauna agency for details.
This Living with Wildlife Fact Sheet is designed to give you some guidance about the procedure you may expect when a snake is in your backyard or elsewhere on the property.
When to call for help
Logically, you will need to call for assistance if a venomous snake is in close proximity to people. That will mean inside an occupied dwelling, a schoolyard, or a factory or shop which is in use. Another occasion when you may consider calling for help includes if a snake in the yard potentially endangers a pet. A snake trapped in bird netting or wire netting also requires attendance.
In Australia, somewhere between 1000 and 3000 people are bitten each year by snakes (White, 1995). Be aware that a high proportion of these bites occurs when a person attempts to kill the snake, or interfere with it. Call a snake catcher/controller instead!
What to do if you see a snake
Under no circumstances interfere with it in any way. Do not poke it with a stick or broom, do not approach it if in the open, do not throw anything at it, and do not spray water at the snake. There are two reasons for you to NOT to do anything: one is the possibility of a now hurt or annoyed snake attempting to defend itself against the aggressor (you). Secondly, your actions are likely to make it much harder for a snake catcher/controller to find, catch and remove the snake.
It is advisable, if you can, and feel comfortable to do so, to watch the snake from a distance that will not cause a reaction - how far away will depend on what it was doing when you saw it, and where it was at that time. If you saw the snake (eg sunning itself early morning), on a path at the edge of a garden bed, you may be able to backtrack but still see it before it is aware of your presence.
After phoning for help, return outside and keep an eye on the snake. Before you do, make sure you are wearing long pants and covered footwear (boots are best), in case you unwittingly get too close to the snake. If you have a portable or mobile phone, take it with you in case the snake moves. You can carefully follow where it goes and immediately update the catcher/controller if necessary. When your saviour arrives, by not interfering with the reptile, but knowing to where it has moved, you increase the chances of it being found and removed.
What is the potential to be bitten?
Scientific studies conducted in recent years in New South Wales have shown that Eastern Brown snakes are NOT aggressive, despite popular opinion (Whitaker and Shine 1999). Extensive experience by Living with Wildlife obtained during numerous Venomous Snake Training Courses from 1993 to 2002, throughout Australia, has also shown that other species of snakes react similarly.
Check the Fact Sheet "Interactions between humans and Eastern Brown snakes" for further information about the research noted above.
For Snake Bites
Do not wash the bite site. A swab from the bite site can sometimes help identify the snake.
Use a broad crepe bandage to cover the bite, going at least one bandage width below the bite and up the limb either up to the armpit or down to the groin. Make sure the bandage is as tight as you would do for a sprain. In most cases the bite is on the lower limb so more bandages may be needed. Any sheets, towels or clothing may be torn up to make strips. Immobilize the limb using a stick or a rolled up newspaper and tie it too the limb using a sling. It is important to keep the victim at rest. Bring transport to them rather than have them walking, especially if the bite is on the leg. Take to the nearest hospital or call an ambulance. If alone the victim should apply pressure to the bite site, try to remain calm and seek help (after applying first aid. Use your mobile phone.
DO NOT USE A TOURNIQUET
Compared with overseas venomous snakes, most of Australia's elapids (front-fanged venomous, land snakes) have relatively short fangs at the front of the upper jaws (White, 1987). The average fang size of a Brown Snake is 2.8mm, while that of a Copperhead is 3.3mm, Tiger Snake 3.5mm, Red-bellied Black Snake 4.0mm, Death Adder 6.2mm and Mulga Snake 6.5mm. One of us (from Living with Wildlife) knows from experience that the fangs of a 2 metre Mulga Snake cannot penetrate leather boots.
What that means to you is if you are wearing long pants like jeans, and leather boots, the likelihood of an effective bite from an average-sized snake is remote.
Questions you may be asked
A snake catcher/controller may ask you some of the following questions when he or she first speaks with you about your problem:
1/ Who actually saw the snake?
2/ For follow up details to locate the snake when on site
3/ Is someone watching it at present?
4/ Gives an indication of the value of responding to your call.
5/ How long ago was the snake seen? If "yesterday", or even "this morning", or unless you know precisely where the snake is hiding, there is little chance of catching it. Be sure to call as soon as possible after seeing it.
6/ Where was it seen? This information helps the snake catcher/controller determine if they can help you. If you say "under five tons of mallee roots", you may not get an enthusiastic response. Check the Living with Wildlife Fact Sheet "How to make your property snake UN-friendly".
7/ What size was the snake? These questions help the snake catcher/controller understand what they may be dealing with. Saying that it was, for example, "six feet long" is often inaccurate as few people can estimate the length of a wriggling snake even in the open. Giving a size such as "as thick as one finger", or "as thick as my wrist" is a better guide.
8/ Also, what colour was it, and did it have any markings? Australian snakes like Browns and Tigers have a great variety of body colours and/or markings. Tiger Snakes may be brown without bands on the body (Ehmann, 1992). Brown Snakes can be almost any shade of brown, as well as greenish, chocolate and even blue-grey (a specimen found in Adelaide)
9/ Snake inside a building? You will be asked if you can contain the snake to a particular room by shutting all doors, and placing anything under the doors (eg towels, rolled up newspaper) to stop it escaping before the catcher/controller arrives.
Ehmann, H. 1992. Encyclopedia of Australian Animals. Reptiles. Angus & Robertson
Whitaker, P.B. & Shine, R. 1999. Responses of free-ranging brownsnakes (Pseudonaja textilis: Elapidae) to encounters with humans. Wildlife Research 26: pp 689 - 704
White, J. 1987. Elapid Snakes: Venom Production and Bite Mechanism. In: Toxic Plants & Animals. A Guide for Australia, ed. J. Covacevich, P. Davie & J. Pearn. Queensland Museum
White, J. 1995. Clinical Toxicology of Snakebite in Australia and New Guinea. In: Handbook of Clinical Toxicology of Animal Venoms and Poisons, ed. J. Meier & J. White. CRC Press