Hindmarsh Island seems to be covered in Myoporum insulare. While the fruit is edible it does have a strong gin like flavour which puts me right off. Juniper happens to be a key flavour of gin which I think is one of those spirits you either love or hate. There is a small boutique distillery on Kangaroo Island making gin with the the Native Juniper. On all accounts if you are a gin fan they are producing gin that is up there with the worlds best.
Juniper berries are also a traditional ingredient added to sauerkraut. As cabbage season is months away these berries could be preserved for using later on possibly by drying. They could also be used in meat and game recipes as you would use European Juniper berries.