- Our Town
A longer look at sponge reef off Dorman Point
In early November, local diver Adam Taylor participated in a group dive off of Dorman Point to explore a local Glass Sponge Reef Bioherm. The amount of exploration they could gather during this dive was limited by the depth of the sponge and the amount of time the divers needed to de-compress after going down 36 meters. This weekend Adam joined his friend and fellow-diver Glen Dennison on another expedition to get more detailed data on the reef. They used a video camera built by Dennison that took hours of footage at a range of depths, with the deepest point being 152 meters.
From the boat, Dennison guided the drop-camera with a high resolution map. As it travelled though the water, the longitude and latitude of the camera was recorded automatically onto the video footage. Taylor will carefully watch the video and record the co-ordinates onto a 3-D map in order to build on the understanding of the sponge coverage of the bioherm.
Dennison said that the sponge maps will help the Department of Fisheries and Oceans know what areas of need special protection from bottom trawling and prawn fishing, and also provide more data for marine scientiss.
The video footage gathered by the drop-camera also offer a closer look at the species of sponge and other sea-life that gravitate towards the reef.
“It looks as though the reef off Dorman Point is in fact a bioherm, meaning, sponge growing on top of dead-sponge, with at least four different species present,” says Taylor. “Subject to confirmation from biologists, we’ve spotted at least four sponge species - Cloud, Goblet, Sulphur and Ball. We also spotted numerous fish species including a variety of rockfish, four species of sea stars, squat lobster and some sea-slugs.”
Taylor, Dennison and the Marine Life Sanctuaries Society are hoping that with the help of some funding, they can arrange for a technical diving expedition to collect Sponge specimens, install a temperature monitoring station inside the bioherm and possibly a permanent underwater web camera.