Showing posts with label Great Barrier Reef. Show all posts
Showing posts with label Great Barrier Reef. Show all posts

Wednesday, June 29, 2011

Missing News: Great Barrier Reef - no net decline between 1995 and 2009

Another story missing in action. This one about a paper published back in March in the journal PLoS One. The paper titled Disturbance and the Dynamics of Coral Cover on the Great Barrier Reef (1995–2009) by Kate Osborne, Andrew M. Dolman, Scott C. Burgess  and Kerryn A. Johns includes the following findings (below), that appear to contradict recent claims reported by the ABC made by a certain coral whisperer.

"Monitoring data collected annually from fixed sites at 47 reefs across 1300 km of the GBR indicate that overall regional coral cover was stable (averaging 29% and ranging from 23% to 33% cover across years) with no net decline between 1995 and 2009."


"Crown-of-thorns starfish (Acanthaster planci) outbreaks and storm damage were responsible for more coral loss during this period than either bleaching or disease despite two mass bleaching events and an increase in the incidence of coral disease. "


"While the limited data for the GBR prior to the 1980's suggests that coral cover was higher than in our survey, we found no evidence of consistent, system-wide decline in coral cover since 1995." 


"This study indicates that at the scale of the whole GBR there was no net decline in live hard coral cover between 1995 and 2009."


"Surveys in 1998 and 2002 identified large areas of reef where coral was bleached. Our results indicate that mortality was not widespread or severe at depths of 6–9 meters. "


 "The impact of bleaching and coral disease, to date, was not severe on our sites."

Tuesday, April 13, 2010

Shen Neng 1 - How significant the damage?

COMMENT: ABC report that the Great Barrier Reef experienced "significant" damage due to the grounding of the Shen Neng 1:
PM 13 April 2010- Ship leaves 3km scar on Barrier Reef
News Online 13 April 2010 - Oil found on beach near damaged reef,  Reef damage from carrier stretches 3km

Some perspective:
Area of Great Barrier Reef: 344,400 square kilometres (source
Area affected: 3 km x 250 m = 0.75 square kilometres"This scar is more in the region of 3km long and up to 250 metres wide.'' (via The Australian)
Area "pulverised": 0.025 square kilometres "There is a footprint of at least 250 metres by 100 metres that has been completely pulverised and wiped clean of any marine life."
Proportion of reef affected: 0.00000218
Proportion of reef pulverised: 0.0000000726

...but apparently marine life abounds: 
ABC image to accompany PM report "Ship leaves 3km scar on Barrier Reef. Caption reads: "Shen Neng 1 has been refloated but has left the reef deeply scarred."