Weedy reo.

[seaslug]

I thought this looked a bit interesting. Some reinforced concrete blocks had been dumped in the sea off the Mersey river breakwater. Must have been there for sometime as they are pretty well overgrown. Should make for some nice habitat for marine life. An artificial reef I didn't have to help build!

[Sully]

:chin:How long would it take for the flora to start establishing itself on the concrete (or is that a "how long is a piece of string" question) ....

[seaslug]

It is a bit like that, as it's so much affected by the sea conditions. In relative calm and temps between 15 & 20C as we get in summer you get excellent cover in a couple of months. Some kelp species grow several feet a day in the right conditions.

In shallow water the weed is knocked about and torn off by wave action, but in deeper water eg. 15-20 metres, the waves have less affect.

The Reef ball reef, established in 18 -20 metres, by the Scuba Club I'm involved with, had good coverage after one month and after six months, sponges and other marine animals had established a permanant home.

Weed and tiny marine animals start establishing themselves almost from the day the concrete is submerged. Their 'spores' are always present in the water column and are looking for somewhere to attach. It's amazing just how quickly previously ecologically damaged sites can rejuvinate when the cause is removed. There are a couple of excellent examples here on the NW coast of Tas.

[Sully]

Thanks for all the info Greg ..... It is a 'place' I know virtually nothing about ...... amazed that some kelp can grow a couple of feet a day.