Busselton Jetty is 2km long and on the day we were there it was very windy. We opted to take the train out to the underwater observatory at the end of the jetty rather than walk 4km in a howling gale.
The train has clear plastic curtains which they can roll down to protect passengers from the worst of the wind and rain. On the way back, the wind was so strong they thought it would blow the train over if the kept the curtains down, so they rolled them up and we were fully exposed. The train doesn't move very fast ...
The underwater photos show the variety of life which has colonised the piers of the jetty. There are lots of fish, crabs and octopus down there, but they mostly moved too fast to catch with the camera.
When we got back to the beach end of the jetty, we watched a bloke hauling up crabs. He'd drop a pot with a bit of meat in it and watch the crabs walk across and climb in only seconds later. It only took half an hour to fill his quota of 20 for the day.