We have three species of grebes in the Ballarat district, all of which obtain most of their food by diving.
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Fish, yabbies and mudeyes are caught by all three.
The grebes involved are the great crested, the hoary headed and the Australasian.
The latter two are smaller and dumpier, being only half the size of a duck, and smaller than a coot.
Today's photo shows an Australasian grebe with a young redfin that seems too large for the bird.
The fish was probably swallowed whole after a bit of uncomfortable twisting and turning.
Most books and websites list the food of this grebe as insects, such as the nymphs of dragonflies, mayflies, damselflies and so on. Water snails also seem to be eaten, but larger items are taken if the opportunity arises.
Photographer Ed Dunens has evidence of other small fishes and yabbies being caught by Australasian grebes, indicating that their diet is more than insects.
The similar-sized hoary headed grebe is also said to catch insects and similar prey, rather than fish. It is likely the two grebes have different prey preferences.
Studies on the hoary headed grebe indicate that it feeds towards the bottom of wetlands, rising to shallower levels when dark skies prevent clear vision at deeper levels.
The little information available suggests that hoary headed grebes might eat smaller creatures than do Australasian grebes.
Both species have the interesting habit of turning their tails to the sun when they come up from a dive.
While not a prominent feature, it is clearly noticeable after a minute of observation.
The birds are said to have dark skin on their backs that absorbs solar heat, even in dull weather.
It is surprising how soon they turn their tails to the sun, even in cloudy weather - when many humans would be disorientated.
SWAMP RAT
A short video from Ballan shows a dark-coloured mouse-like mammal scampering around in long grass and twigs.
While positive identification is difficult, the animal appears to be a native swamp rat. It is clearly larger than a mouse, and its tail is shorter than that of a black (common) rat.
Unlike many native Victorian mammals, the swamp rat is active throughout the day. It eats stems of grasses and sedges, as well as some insects, particularly in winter.
I am not sufficiently familiar with the swamp rat to know whether it climbs up twigs to seek food. Most of its activity is on the ground or in burrows that it digs.
It is an animal of southern Victoria, with Ballan well within its known range.
NATURE QUERIES ANSWERED
What is this strange-looking fungus? It and others are in the North Gardens. They look amazing.
C.N., Lake Gardens.
Your photo shows the velvet-top fungus. It is parasitic on stumps, roots and trunks of pine trees.
Although it might appear to be growing on the ground, it will be attached to the tree roots.
Your specimen is fairly fresh. It turns dark brown and stiff as it ages. Sometimes a second tier or level appears.
Fresh, circular specimens can resemble large fruit pies or tarts. They are not edible.
This is an introduced fungus, from the northern hemisphere. It was once used for dyeing material.
Another name is dyer's mazegill. It is not included in many Australian fungi books, but it is listed on quite a few internet sites. Phaeolus schweinitzii is its scientific name.
- Questions and photos are welcome. Email to rthomas@vic.australis.com.au, or send to Roger Thomas at The Courier, PO Box 21, Ballarat, 3353.