There were two different calls heard from the Bendigo birds, both of them sufficiently different to be unrecognisable until the calling birds - more than one - were tracked down.

White-eared honeyeaters sound different in the mallee and along the Victoria coast too. The calls are mostly identifiable, but they sound different from the calls of Ballarat district birds.

The same applies to the grey-shrike-thrush. This species has a range of calls throughout the year, but some of the calls in other regions are rather different from those of our local birds.

Calls of migratory and nomadic birds with wide distributions - such as rufous whistler, mistletoebird, brown-headed honeyeater, pardalotes and red wattlebirds - do not vary across their range. The silver gull is the same.

It is the birds that stay at home all year that sometimes develop local dialects. Someone with a keen ear might notice variations in the calls of magpie, magpie-lark, crimson rosella and others in different parts of Victoria or Australia.

Grampians crimson rosellas sound slightly different from ours, for example. Calls of eastern spinebills near Sydney are different from those of Ballarat birds. Grey butcherbirds vary from place to place. However, the call of the laughing kookaburra does not seem to change much across its range.

CYGNETS

The season's first cygnets have been reported surprisingly early, at Yuille's Wetlands at Sebastopol.

Yuille's Wetlands are alongside the Yarrowee River at the end of Vickers Street, Sebastopol. There is often a small range of waterbirds present there. A boardwalk makes viewing easier.

No nesting swans have been reported at Lake Wendouree so far, but sometimes the cygnets appear there before nests are known.

Another surprisingly early bird report concerns reed warblers at Lake Wendouree. At least two of these birds were heard calling in the central reeds on June 28.

There are occasional - but not annual - reports of reed warblers during winter at the lake. They are sometimes heard calling on calm sunny days, just as we have had recently. Reed warblers generally move north for winter, with the first birds returning in the last week of August.

Two weeks ago, we wrote about the first sighting of banded stilts at Lake Wendouree. The first recorded sighting of this species at the lake was actually in 2014. There was also another sighting in 2016.

How many sorts of grass-trees grow around Ballarat and where do they grow?

K.C., Alfredton.

There are two species of grass-trees (Xanthorrhoea) growing wild in the Ballarat district. One has a trunk and the other doesn't. The prominent species at Canadian is the austral grass-tree. It has a trunk. It also grows north to Nerrina and south to Lal Lal and the Brisbane Ranges, as well as north of Beaufort.

The small grass-tree is very numerous in the Creswick and Enfield - Linton forests. It never develops a trunk. There are four other species of grass-trees in other parts of Victoria. All have similar long, angled leaves that can cut if handled carelessly. Some species have leaves that are triangular in cross-section, while the leaves of others are quadrangular. They are not always easy to distinguish from each other.

Send questions to Roger Thomas at The Courier, PO Box 21, Ballarat, 3353, rthomas@vic.australis.com.au