Hi Bird-lovers,
Just a few thoughts to add to the discussion, after some useful and well
thought out contributions on the subject.
Alan, you are absolutely right, the Weekly Times article clearly
over-simplified the situation and ignored a lot of information that would
have provided some balance to the debate ( as perhaps did my original
posting written in a hurry late one night).
Keith kindly summarized some of the history of grassland management in the
Terrick Terrick National Park, which paints a very different picture to that
portrayed in the Weekly Times. As past secretary of the Friends of the
Terrick Terrick NP, alongside Keith in the committee we both know how
dedicated and well intentioned the park staff are, and this debate should in
no way be a negative reflection on them.
However as Keith knows there have been a variety of ideas as to how to
manage the grasslands, and all sides have not always agreed. Grazing was
reduced considerably in more recent years, although since the floods I
believe that all sides of the equation have realized that we have a problem
when it comes to Plains Wanderers. Again, the Weekly Times article fails to
acknowledge this fact, and the current progress being made in regards to new
ideas for managing these grasslands was not mentioned.
Perhaps to summarize the crux of the problem is that the Plains Wanderer in
more recent times has actually benefitted from broad-acre grazing of rarely
ploughed grassland for economic return. Since they like a very sparse open
structure, with grasses growing only up to 20cms in height, fairly
intensively grazed grasslands do provide a suitable habitat for them.
Grasslands managed such as this however have the potential to lose botanical
diversity if grazing is too intense, and continuous when native plants,
other than grasses, are seeding. Rare plants are important as well as rare
birds.
Grasslands are an incredibly dynamic environment, altering greatly both in
density and species composition from year to year as rainfall varies.
Plains Wanderers are no doubt adapted to these vagaries, and have the
ability to seek out more suitable areas to inhabit when conditions change.
Trying to piece together how it all functioned before white settlement is
tricky, and largely conjecture, but the forces helping Plains Wanderers
would have been drought, ( we still get these), grazing animals ( kangaroos
of which there were large numbers originally ), locust plagues ( which are
now largely sprayed out in Victoria), and fire utilized by native peoples
(possibly the most important of all particularly in better seasons ).
In just a few short centuries we have changed the effects all of these
forces to varying degrees. The biggest change has been cultivation which
changes a grassland forever. In Victoria never ploughed native grasslands
are rare as hens teeth, and even in the twenty years I have been here, they
are still disappearing. Ploughed grasslands, where the soil-surface layer
has been damaged, support many more introduced grasses and are more prone to
thickening up, particularly in winter/spring. Plains Wanderers do not like
it when the inter-tussock spaces disappear.
Even if we returned to a pre-European style of management (if that were
possible), I doubt it would be enough to keep sufficient habitat for the
Plains Wanderer in Victoria except perhaps in the driest of years. And the
fact that remaining habitats are so rare and isolated compounds the problem,
as when Plains Wanderers have to move, it must be much harder for them to
find somewhere else that is suitable to hang out.
For these reasons I believe that continued grazing is the most realistic
tool available to keep sufficient habitat to support viable populations,
with carefully managed burning a potential second string.
Growing up in Britain I am used to seeing conservation efforts that are
based on continuing a particular land management practice from centuries
past, to maintain a habitat which encourages a particular species or
biodiversity generally. There are many examples of this. Grazing of chalk
grasslands, coppicing of woodlands for Nightingales, and old fashioned hay
making operations are a few that immediately come to mind. It does not seem
to me, to be much different from the idea of grazing native grasslands in
south-eastern Australia to maintain suitable Plains Wanderer habitat.
As a guide, who has shown people Plains Wanderers in the Terrick Terrick NP,
on the Patho Plains and on the Avoca plains of Victoria for some years now I
have had the absolute privilege to see the native grasslands in drought and
in flood, with grazing and without, and with and without Plains Wanderers !
I am pretty confident now that this special bird will not be forgotten when
it comes to grassland management.
However in saying that, I would like to address a couple of ideas that I
encounter quite regularly, and which I think need to be put out there.
Firstly, and I still hear it , is the idea that when the grasslands thicken
up, there are still a few Plains Wanderers hiding out there, it's just that
they are harder to find, so they are being missed. I am absolutely sure that
this is not the case from my and others experience, and recent experiments
using Plains Wanderer dummies placed at random in a grassland also debunk
this idea .
Secondly, the line goes that given the huge rainfall and flood events that
we had in the last couple of years, no amount of grazing would have
contained what happened. So it's a natural event and would have happened in
the past, and Plains Wanderers will come back when it dries out again. To
this I would just say that even through the wet years, there was still
habitat suitable for Plains Wanderers on privately grazed grasslands, where
grazing was continuous, plus given the fact that these birds now have
dramatically fewer options of where to go in a wet year, perhaps they have
not moved on, survived somewhere else, and will return ok. Perhaps the birds
have perished due to having nowhere to go, and the population has crashed
nationally ? Reserved grasslands on the Patho plains were thickening up too
much for Wanderers after a couple of wetter summers, well before the really
big rains came in 2010, because of the much reduced grazing regime that was
introduced. When the big wet arrived, the scene was already set and in many
places the grasses were 8 ft high.
Some properties on the Avoca plains west of Kerang, which were purchased for
conservation reasons towards the end of the drought, and which had been
heavily, perhaps too heavily grazed, and which supported Inland Dotterels
(perhaps not a species that would occur as far south as north-central
Victoria without human intervention ), are now after a couple of years of
good rainfall and no grazing already growing grasses that well above the
20cm ideal maximum for grass height for Plains Wanderer. This shows how
dramatically a grassland can change, and how without some intervention, the
right habitat structure will disappear.
Finally, and I have no wish to speak for others, but recent contact with
other plains wandering birdwatchers including some very well known ones,
suggests to me that the situation as to their population numbers is similar
across the wider riverina as it is in my small part of northern Victoria,
and that is that they are extremely localized and in low numbers generally.
Interesting times !
Cheers,
Simon Starr.
Victoria.
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