You're correct that these Torresian Crows can, at times, exhibit aggressive behavior, and, unlike some other crows, may directly attack people. It stems from a defensive parental instinct though, and is territorial in nature. According to The Brisbane City Council's page on Swooping Animals, they, and some of Brisbane's other native birds, are most likely to swoop people during peak breeding time, which is between July and December. As you've found out by experience, each nesting cycle during that time usually lasts up to six weeks. The swooping is a normal defensive behavior, generally caused by a bird with eggs or newly hatched young in the nest. The people who are most vulnerable are those who are closest to the nest. The crows do establish territories which extend beyond the actual nest, and may include your backyard, street, local park or field areas, or buildings like an office or school, so people may not even know where the nest is. In your case though, the nest is right nearby, so you know exactly where it is, and, unfortunately, you're in the direct path of the most vulnerability!
There are things you can do, some of which you've tried, which, unfortunately, haven't been working for you.
The WildlifeQld Snake Catcher Brisbane & Bird Management is a good source of have information about birds and crows, including a page dedicated solely to the Torresian Crow (Covus orru).
As you said, they're protected in your area, for several reasons, primarily because they provide natural pest management. They eat insects and small rodents in agricultural, woodland and suburban gardens. Through defecation in these areas, they disperse seeds which helps growth and survival of native crops. They also eat animals which are already deceased in the road, providing assistance with clean-up, and also creating a continuing benefit to the ecosystem.
The following is their advice. I know you've tried some of these things, but I'm leaving them in so the answer includes the complete list.
- Don't interfere with the bird, its nest or the chicks.
- Crows are a protected species under Australian law and attempts to harm or kill these birds are illegal. These birds are merely protecting there young from a perceived intruder in much the same we would our own children.
- Don't feed crows. It is commonly believed that by feeding these birds they become friendly and won't become a nuisance. The truth is it encourages other animals into the area to take advantage of a free feed.
- Avoid the area. If there is an alternate way of getting to work, going to the shops or taking the kids to school then use it instead. It's a small price to pay when considering a potential injury.
- Where possible keep your eye on the bird. In most cases the bird will not swoop and make contact if it sees you are watching. If the bird does approach the simple waving of an arm will deter it from making physical contact.
- Carrying a hat, umbrella or alternate object which you can hold above you head can help in deterring birds from swooping. Walking in a group can also be a great tactic.
- Placing eyespots on your bike helmet, wearing sunglasses on the back of your head or keeping the bird in eye contact may in some cases help prevent swooping. Crows like magpies utilise the element of a surprise attack when you're not looking. Therefore maintaining eye contact, or the illusion that you are, may as previously mentioned aid in deterring them.
- Don't harass the birds, as this can make them more aggressive and more likely to injury someone else.
- Informing your local council and having them erect signs is a great way of informing residents of swooping birds in the area so they are aware of the temporary risk.
Source
If the birds, even when not breeding, haven't moved away on their own, you can seek removal or relocation assistance, however, and this is very important:
Never try to remove or relocate even one of these birds, either on your own, or by calling a "relocation specialist" People advertise themselves as "certified" or "licensed" in order to make money, so be careful when seeking help. Only people with certification from the Environmental Protection Agency are authorized to help, and there's a strict process they need to go through to receive the proper certification.
Advice & Relocation
If your best efforts of deterring the bird fail then further advice or relocation may be your last resort. Ecologically-minded crow advice, specialist trapping requirements, and ecologically sound translocation methods are employed by licensed professionals for effective crow relocation.
Trapping & relocation of the bird is done in accordance with requirements stipulated by the Environmental Protection Agency and permits are issued after stringent examination as to knowledge and suitability to actively manage conflict crows.
Every effort is made to ensure the birds are managed as to welfare, and to minimize any possible harm whilst being trapped, upon trapping, and through transit to a suitable release site. Source.