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
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