Harbour biodiversity (2 of 3)

Whilst the ferry, Proclaim, hove to, Dr Poore discussed with us some of the underwater life around the very popular (in season, of course) swimming beach, Neilsen Park, which is on the southern shore of the harbour. Much of the harbour foreshore is national park.

Neilsen Park is one of a number of harbour beaches that has a shark net.


This net has encouraged a growth in the population of a tiny variety of seahorse which uses the netting as a breeding ground. So many seahorse cling to it, that it gets too heavy to do its job properly and each off-season, is 'cleaned' by National Park rangers and UNSW researchers. Sydney Harbour is home to two species, the potbelly seahorse and the more common White's seahorse.

Just in front of the sandstone rocks, is an underwater 'field' of seaweed which has been infested by the Long-Spined Sea-urchin which breeds in warmer waters. Because the Eastern Australian Current is 2 degrees warmer over the last decade, this urchin has now spread as far south as Tasmania with disastrous effects on the more jungle like seaweed in those waters.

Harbour biodiversity (1 of 3)

With 60 others, I jumped aboard the Rosman Ferry Proclaim last week for a 5 hour cruise in acknowledgement of International Biodiversity Day. The National Maritime Museum and WEA, together with the University of NSW and the new Sydney Institute of Marine Science cruised us around a range of sites in the harbour to discuss its health and its marine populations.

It was a perfect autumn day to be on the water, and the stormy backdrop added considerably to the charm of the day.


As we chugged around west of the bridge, Dr Alistair Poore, from UNSW, chatted to us about the original shoreline and the impact on marine diversity of the alterations to this shoreline necessary as the city developed. He showed us sites where there was joint venture research between our universities to ameliorate the hard lines of much of the harbour foreshore.