For those who have expressed some curiosity, duck hunting is regulated in Victoria by the Wildlife Act 1975, and subordinate to that by the Game Regulations 2012. R.32 specifically deals with "toxic" (elsewhere defined as anything other than a list of things such as steel, bismuth, tungsten etc) shot. Here are the specific clauses:

32 Use of toxic shot
(1) A person must not use toxic shot to hunt, take or destroy ducks.
Penalty: 20 penalty units.
(2) Subregulation (1) does not apply to a person who is hunting, taking or destroying, or intending to hunt, take or destroy ducks, in the open season for duck, if the person is using a firearm that is a muzzle-loading, Damascus steel or twist-barrelled shotgun.

This regulation came in some years ago in a phased manner. If I recall correctly, things like sub-gauges and private land retained lead for a little while longer before being phased out. Our local Vintagers - some of them of some standing and seniority in our shooting community, and reasonably well connected - were instrumental in retaining lead's use through damascus barrels, reasoning that so few people would take advantage of such a clause as to cause negligible environmental effect, and that most other allowable options were unsuitable in damascus barrels.

Lead remains in general use for most other forms of hunting and pest control.

Happy to dig out more information if people wish... Unless their communication style reminds me of my ex-wife... then I'll be triggered and have to retreat to my safe space...(!)