[Coral-List] Report of widespread Barrel Sponge (Xestospongia muta) pigment loss.

[Reef Rescue]

On April 27, 2012, Reef Rescue divers completed two dives on Gulf Stream Reef, Boynton Beach, FL. First dive from 26 30.300 N, 80 02.065 W to 26 30.610 N, 80 02.015 W. Observed 22 barrel sponges with pigment loss. Second dive from 26 30 .755 N, 80 01.960 to 26 31.077 N, 80 01.969 W. Observed 29 barrel sponges with pigment loss. Video from the first dive is posted at: http://www.youtube.com/watch?v=rz6Q7wt7Cx8&feature=youtu.be 
 
On April 11, 2012, Reef Rescue performed dives in the same area and observed no barrel sponges with pigment loss.
 
On April 27, Reef Rescue received reports from divers to the north at Horseshoe Reef, Lake Worth and Paul’s Reef, Palm Beach that barrel sponges were “bleaching”. As in Boynton no pigment loss was observed at those locations two weeks prior.
 
Over the last 15 – 20 years of diving in Boynton and Palm Beach County we have observed occasional instances of barrel sponge “bleaching” and disintegration. However, never have we observed an event of this magnitude. A rough estimation is that 10 -15% of the barrel sponges observed on 4/27 were impacted. 
 
Ed Tichenor
Palm Beach County Reef Rescue
www.reef-rescue.org
561 699-8559