Scrub cattle,feral cattle and scrub bulls are the product of domestic cattle that have bred up and or inter bred without being mustered over a period of time and have usually had none or very little contact with humans.
The majority of scrub cattle I have encountered have been a red shorthorn type with big rings around both eyes.
They usually live in isolated and rugged country where mustering is not usually an option unless dry times force them out of cover insearch of feed and water where they may be trapped in trap yards.
Northern Australia including Northern Territory and north Queensland scrubbers appear to have a lot more bos indicus (brahma) blood in them but are just as unpredictable when confronted.

Probably the best person to ask about shooting areas on the east side of Aussie would be Alan Moon who runs an outfit that is involved with that industry.
Al

Alan Moon goes by the name 4-seventy on Nitro X