Banksia Walk, Bribie Island

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WELL hello friends. Today I'm exploring the Banksia Track on Bribie Island. Bribie Island is one of the sand islands near Brisbane. This one is north of the city. Unlike all the other sand islands this one is absolutely flat at no more than five metres above sea level. All the other islands rise up to 200 to 280 metres above sea level.

Here we are in the middle of the banksia forest. It is a very dry forest. All those trees are banksias and under them are grass trees. The grass trees are really interesting. They only grow one centimetre per year so you can easily work out how old they are. The tallest grass trees seems to be 50 to 60 centimetres tall. This means this forest is about 50 or 60 years old and I'm guessing they are the same age as the banksia trees. The grass tree straight in front of me a few metres you can see the great big flower coming out of it. Obviously that will produce seeds which will fall and lie dormant on the ground until the next big bushfire comes through and the bushfire will take them out of dormancy. That is very common for trees in Australia. A lot of the trees (including some of the gum trees and these ones), the seeds never germinate until they have been burnt in a bushfire. The bushfire will also clear away some of the bush making it easier for the new plants to germinate. Here you can work out how often big bushfires come through. One happened about sixty years ago and looking at these other grass trees which are about 20 to 25 centimetres high, so about quarter of a century ago there was another bushfire through here. There's also a few very young ones here. It's a very fascinating area of bush through here.

As you can see on the track all the surface is just sand, pure silica sand which the entire island is made of. The bigger islands (Moreton, Straddie and Fraser) have all got some volcanic peaks holding the sand together at their northern ends contributing to their big sandhills. Bribie doesn't have any rocky landform at all but this is just a large section of flat sand sitting at the entrance of Moreton Bay. If you go out about five or six kilometres in that direction you will get to the sea at the entrance of Moreton Bay with Moreton Island on the other side.

It looks like this is a big firebreak here. They have cleared big firebreaks so if a fire breaks out it will be limited. This is a nice wide clear area for where the fire can be constrained. Where possible we do controlled burnoffs. Having these firebreaks helps control that. They can set one area of bush on fire each year to minimise the risk.

OK friends I'm almost at the end of the track now and I found this little waterhole. There is not much in it at the moment because we are right near the end of our dry season (late spring). Hopefully very soon we will start getting some of the rains. There is a la nina this year which means we get a lot of rain. Hopefully the water will go up a bit more to at least a metre to a metre and a half deeper than it is now. At this time of year the water is very scarce. On a sand island like this there's almost no creeks. These little waterholes are the only source of fresh water the local native animals have here. All the animals like the wallabies, the reptiles, the lizards, goannas, dingoes. There are a couple of dingoes on this island. Then there's also all the snakes and rodents. Obviously though you won't find anything here at this time of day. But certainly as the sun goes down and also early in the morning all the animals will come here. The water is pretty horrible at the moment. Anyway give it a bit of rain and this area will revive a bit. It's certainly tough living out here if you are a wild animal on an arid island like this.

Thanks friends for joining me again today and ciao for now.