> Drought years undoubtedly bring out the crakes and rails, but also I
> think
> that this factor is superimposed on a combination of absolute
> abundance, and
> innate shyness or lack of. My thoughts on a ranking of
> shyness/sparseness are:
>
John
We could probably argue about membership of your various
shyness/abundance "guilds", or vary it state by state, but I think
you're right; it's not just simply a matter of the amount of water.
Take my Bendigo Sewerage Farm example .... the numerous Australian
Spotted Crakes forage in the open, seemingly oblivious to unconcealed
observers, and only bolt for cover when a hawkish silhouette appears
overhead; the Spotless Crake, hugging the edge, sees us and quite
quickly melts into the background; the Baillon's Crake is much like the
Spotted in its behaviour, though less abundant; the Buff-banded Rail is
almost as shy as the Spotless Crake. Last summer at Jerringot in
Geelong there were up to 4 Spotless Crakes foraging out in the open on
exposed mud at any one time, but they were very flighty and bolted back
into cover if even a gull flew over, or a noisy car went past.
I was also interested in Frank O'Connor's comments on crakes vs. water
levels in SW-WA, but I would make the point "Just 'cos you can't see
them doesn't mean they're not there!!". Falling water levels may make
crakes more visible as they forage out from the cover of vegetation, in
order to obtain the invertebrates that they normally incorporate in
their diet, but does that mean they're absent or just invisible when
water levels are higher? (I guess I should look at the literature to
see what they eat!!, but they can clamber round off the ground/water in
lignum and Typha as well as trot around on mud) I've had responses to
taped calls from Spotless Crakes in wet Typha swamps in the Geelong
area, but no luck in actually seeing the birds. This situation may vary
considerably with location too.
Lawrie Conole
Geelong, Victoria, Australia
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