Mouse hunter extraordinaire, the Dugite, Pseudonaja affinis
The lightning fast Dugite of the southern parts of Western Australia really love rodents, although other small mammals and reptiles are not overlooked. The scent of the introduced House Mouse, Mus musculus will have the small to medium sized snakes going to great lengths to doggedly track them down and will even enter through your front door if any mice have taken refuge inside. The larger snakes (to 2 metres below) will seek out the bigger native Bush Rats, Rattus fuscipes. So why this interest in rodents? Maybe their shape has something to do with it!
Young snakes (to 11/2 metres) are long and slender and ideally suited to fitting into a mouse burrow, whereas the larger snakes thicken and will not fit, but do so comfortably down a Bush Rats burrow. The Dugites above and below are large snakes of around 2 metres in length. Both of these lived for a period of time down Bush Rat burrows, where they probably hibernated through winter.
As an example of their interest in rodents, I always have an Elliott trap set to catch any passing mouse in order to stop them breeding up in and around my home. Well I had caught a mouse in the trap the night before, which I had disposed of and then reset. About lunchtime I noticed it had been set off again and assumed I had caught another. So picking it up to see the captive, I discovered the trap was very heavy, much heavier than even a Bush Rat, so I very gingerly peered inside where my gaze was meet by a beady eyed Dugite's. It turned out to be a little over 4 foot in length, but was not really aggressive and was happy to head off into the bush.
The Dugite belongs to the genus Pseudonaja, the Brown Snakes, which generally have a bad reputation for being very aggressive. However, I have never found the Dugite to be so, from my experience they just go about their business with great determination and will completely ignore you. If confronted they will seek the fastest mode of escape, preferring to flee rather than fight. This I should add only applies to the younger snakes, once they mature, they should be treated with the greatest respect as all large adult snakes are very sure of themselves (being a top predator) and do not submit readily, but will still get out of your way if given the opportunity.
The length of these snakes varies and like the Tiger Snake, are usually smaller on offshore islands, where two subspecies are recognised. Coloration also varies from dark colored ones to the brown ones near me that usually are heavily flecked with darker scales and some (as with the top photo), with a dark brown head.
I have noticed with the Dugites and Tiger Snakes that they occupy a territory and if you are part of it, will return periodically. If there is nothing for them to eat, they will move on, but if not they will stay until they have caught it, or it does a runner. These snakes have good memories and certainly recognise permanent residents and I believe go out of their way not to interfere with you. Even if you come across them suddenly there is no attempt to strike, but only to get out of your way. I like snakes, they are very accommodating!