Thankyou for the brief but informative insight into maintaining fire regimes.
It was definitive in respect to laymen, like myself.
Cheers,
Mark Kliene.
Michael Todd wrote:
> Hello Stuart, Craig and others,
>
> As is usually the case with these kind of things, the importance and impact
> of burning on flora and fauna depends on where and what you are talking
> about. If talking about northern Australia then the frequency and timing of
> fire is crucial in the survival of many animals including birds. Of course
> what is good for one species can be bad for another. In the case of
> finches, the habitat of the Star Finch on Cape York Peninsula has almost
> certainly been maintained by regular and widespread burning of the
> grasslands. Without the fire, the grasslands are invaded by shrubs,
> particularly Melaleuca spp. Anyone who gets the chance should take a look
> at the Nifold Plain grassland on Lakefield NP, with the Melaleuca advancing
> at the edges. You can almost watch them spreading! The grassland which
> supported Stars here was once much larger than it is now.
>
> On the other hand, the white-bellied subspecies of the Crimson Finch is
> probably negatively affected by fire. Being relatively poorly adapted for
> dispersal (short round wings) it requires undergrowth for shelter,
> particularly the dense canegrass (Chionachne cyathapoda). Large fires
> towards the end of the dry season can clear large areas of all shelter
> leaving the Crimsons exposed to predation. Ironically, fire on a smaller
> scale can help the Crimsons as it reduces the likelihood of large fires
> later in the dry season by reducing fuel loads as Stuart suggested in his
> email. The Chionachne is resistant to burning earlier in the wet season and
> so can form natural fire breaks and shelter for the Crimsons. You can add
> Purple-crowned Fairy-wren to this scenario as it occupies similar habitat
> elsewhere in northern Australia and would be even more affected by large
> fires.
>
> The Golden-shouldered Parrot is hanging on by the skin of its teeth (if it
> had them) thanks to specific burning regimes which are probably putting
> some other species at a disadvantage. But what else can you do? It is
> likely that the current climatic situation is favouring the spread of
> certain habitats (and the flora that live in them) at the expense of the
> others. It has been shown that the rainforest is spreading at the expense
> of tall eucalypt forest in north Queensland threatening the northern
> Yellow-bellied Gliders, Tropical Bettongs etc. See research by Graham
> Harrington. Grasslands are on the way out and it was probably only the
> regular burning carried out by aboriginal people that kept the grasslands
> and their Star Finches alive on Cape York. If we want to keep this habitat
> and I suggest that we do then we have to burn. Exactly how and when we go
> about it can be controversial and is a difficult situation but there can be
> no doubt that burning is crucial.
>
> Stuart says that fuel reduction burns simplify the flora of an area. I'm
> sure that this can happen in some environments. However, some areas that
> are not burned at all can become much less floristically diverse than those
> that are burnt. I hate to keep going back to the same examples but on the
> Nifold Plain, good Tussock Grassland habitat can have something like 20
> different species of seeding grasses in a relatively small area during the
> end of the wet season. On the other hand, ex-grassland that has become a
> Melaleuca woodland is far less diverse in terms of grass species. Grasses
> are unfortunately often overlooked- well, I admit, they are buggers to
> identify. There are many references to comments made by early settlers in
> Australia of the change in the undergrowth they noticed within the first 50
> years of white settlement in SE Australia. Unfortunately, there is probably
> little chance of knowing exactly how these communities functioned back in
> the late 1700's but it seems likely that they were being maintained by
> regular burning regimes. Maybe they were floristically less diverse than
> the same communities are today. They certainly must have been quite
> different to what we have today in terms of their fauna. You only have to
> look at some of the mammals that used to exist in SE Australia that are now
> long gone. The Tasmanian Bettong (Bettongia gaimardi) for example used to
> be distributed right up the east coast of Australia into SE Qld! It
> disappeared so fast after white settlement that there are only a few
> specimens in museums from the mainland. The habitats must have been very
> different then.
>
> However, we may not be able to go back to what it was like 200 years ago.
> Certainly with some animals it is too late as they have gone extinct (eg.
> Eastern Hare Wallaby). We also don't know what the flora composition of the
> communities were, particularly with the grasses, which were assaulted by
> the trampling and grazing of cattle and sheep on top of the change in
> burning regime. So, do we try to recreate what it was like 200 years ago or
> forty years ago, which is probably closer to what it might have been like
> 40,000 years ago, give or take a few species of giant kangaroos. This
> becomes a question of philosophy. There is no right or wrong - just a lot
> of uncomfortable compromises.
>
> There are probably no easy answers. Some species will be negatively
> affected whether you burn or not. Its a no-win situation. Many small birds
> may require dense undergrowth without burning, Chestnut-rumped Hylacola and
> Southern Emu-wren spring to mind from my home area of Lake Macquarie.
> However, places that have had no burning for many years lack the Spotted
> Quail-thrush and Painted Button-quail. Its also easy to only think from a
> particular perspective, ie birdwatchers only thinking about the birds. What
> about all the other animals and their requirements re fire. Common Dunnarts
> require fire to keep the understorey open and the Brown Antechinus out. If
> there is no fire then the undergrowth thickens up and the Brown Antechinus
> and the rats move in- bad news for the dunnarts. Its a complicated matter.
>
> I hope I haven't bored too many people with my rambling! I think I'll go do
> some burning for those dunnarts. Only kidding!
>
> Cheers,
>
> Mick Todd
>
> Michael Todd
> Toronto, NSW, Australia
> email-
>
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