ANDREW CHARLTON AND SAXON DURRANT
Perth holds the title for highest reptile species variation in the world, but we might not have it for much longer says Edith Cowan University biologist Rob Davies.
Dr Davies says Perth has an abundance in both variation of reptile species and population of those species.
“Urban bushlands in Perth do support very good reptile populations,” he says.
He says we have up to 65 different species of reptiles within 100km of the city, higher than in any other city in the world.
Dr Davies focused on reptile habitation in his research, and found that many species reside in old, long unburnt areas.
“A whole bunch of reptiles like older areas, because as they get older they get more leaf litter, they get more of a dense structure,” he says.
“Some reptiles really like that and they don’t like burnt areas at all, so obviously that’s getting more rare as things go on.
“My study was focused on urban bushland and I guess all the reserves we have scattered around Perth and there has been a very dramatic increase in fires.
“Because you know so many people have been moving here, bushland gets surrounded by houses, and whether it’s kids playing or people deliberately lighting fires, the number of fires has definitely risen over the last few years.”
According to the Department of Fire and Emergency Services, there were 1312 suspicious and deliberately-lit fires in Perth in 2013-2014.
Owner of the West Australian Reptile Park in Henley Brook, Gane Doyle, knows of the incredible diversity that Perth is blessed with, having built his life around reptiles.
“[If] you go digging in your garden you might find three different types of little skinks just burying under the mulch or the leaves,” Mr Doyle says.
Mr Doyle says that fire in its very nature is damaging to reptiles, no matter even if our vegetation has become used to it.
“If it’s a fast, hot fire most of the snakes and lizards and any reptile will not be able to get away,” he says.
“They’ll be dead before they get burnt.”
A veteran with more than 40 years experience in the handling of reptiles, and owner of his own park which includes snakes and crocodiles, Mr Doyle has seen the changes due to the expanse of the Perth metropolitan area.
“I’ve already seen it over 40 years, numbers have dropped right off in certain animals,” he says.
“The animals haven’t got a chance … we’ve got to slow down.”
Mr Doyle criticised the practice of leaving sections of bushland in the middle of suburbia. He says that if there is no corridor to other bushland then you “might as well just build on it”.
Dr Davies says that the key problem for reptiles now is the frequency of burns, as they’re being left with very few unburnt areas to live in.
“In an ideal world, possibly pre-human, certainly there would be large areas that experience burning but also large areas that would go a long time unburnt,” he says.
“Recent studies show that ideally 20 to 30 per cent of the Swan Coastal Plain vegetation should be long unburnt, so 30 years or so, but really only around 2 per cent of it is, so species that live in those long unburnt areas aren’t getting what they need.”
Dr Davies says the way forward is experimenting with controlled burns.
He says these protect areas unburnt by making a mosaic of burns around them, so a large, powerful fire cannot take hold.
“The beauty of doing [these burns] well, just burning small patches is that you break up the vegetation so a large scale fire and a really hot one that could wipe out the whole remnant won’t happen,” he says.
“If you imagine, fuel loads build up for years and a whole park gets burnt, then these reptiles have no hope.
Dr Davies says both reptile and mammal populations along the Swan coast have dropped dramatically over the decades, and to preserve them we can’t just set aside remnants and reserves and say: ‘It’s fine’.