Declines, denial and disconnect: Victorian reptiles in a time of mass extinction

On a wet and wild Saturday June 16th, a hardy group of people gathered at the Mural room, at parks office Halls Gap, for a passionate and informative talk given by Nick Clemann.

To the editor’s delight, two attendees Bill Gardner and David Steane sent reports from the talk, which I have combined. Many thanks to both of you. An example for others to follow!


Nick works on threatened species of fauna, in particular reptiles and frogs. He also does honorary work at the museum of Victoria, the zoo and university.

We are in the middle of the 6t h extinction period because of the emerging catastrophe of the Anthropocene (age of man). Prior to this the most recent mass extinction event occurred in the Cretaceous when the dinosaurs were lost due to collision with a large meteor. Factors leading to the current rapid rate of species disappearance include:

  1. Climate change
  2. Habitat destruction from introduced herbivores such as horses, deer and pigs. Horses are particularly destructive of alpine streams and wetlands, causing the direct reduction in numbers of frogs and wetland dependent reptiles,
  3. Pollution
  4. Over fishing/hunting
  5. Invasive species
  6. Overpopulation of one species…man (this is rarely mentioned in polite society!)

The current rate of extinction of other species is more than 1000 times the background rate.

Survey work done by Bandow’s expedition in 1856-7 was used to provide a base line point to document extinctions. While most people are aware of large, warm blooded cuddly animals which have disappeared e.g. various mammals, and particularly thylacines, few realise that the attrition in reptiles (29 taxa/120 recorded) and frogs (12 taxa /37) is far greater, just based on these records alone.

            Other species are at risk, for example the striped legless lizard which has lost 95% of its habitat. Conservation and species rescue however is a popularity contest for funding and few people like frogs and reptiles. Only one frog has been funded for study in Victoria, the BawBaw frog. A fungal disease of frogs (Chytridiomycosis) which has multiple strains, is causing rapid extinction across many (most) species.

Solutions?

Habitat retention….should be major goal…destruction continues even when habitat is near to zero

One problem is that developers can argue to undertake mitigation of habitat loss by the use of off sets (ie creating or preservation of new habitat elsewhere). But if there is no more habitat, this is an illogicality. Relocation is not the answer as typically it fails! Translocation has a last ditch role in conservation but cannot be used as a justification for habitat destruction.

            Translocation is not a simple process. In the case of frog disease, captive husbandry and release of tadpoles or adults is possible. There is scope to experiment in captivity eg select for disease resistance. There are many variables which influence the outcome of any attempt to reintroduce a species (eg water quality can sometimes be antifungal, typically a bit salty…has a bad impact on frogs, but an even worse effect on the disease)

Some good news

   A current project studying the venom bank of snakes has found geographic and temporal variation in venom strength; ontogenetic variation in young vs adult. The use for medicinal purposes may drive the funding for more work into awareness of snake species and lead to action preserving their numbers i.e. use /practical benefit to be seen to the public. The old story…a species only has worth if it is of benefit to mankind…but that is the reality of the funding situation.


After Nick’s talk, a dozen or so people went to Halls Gap hotel, for a well-deserved meal and drinks. Thanks Nick for a great talk.