A number of expert witnesses for Rena's owners say they believe there would be no significant lasting ecological effects from leaving the wreck remains on Astrolabe Reef.
During the third day of the resource consent hearing at ASB Arena, Dr Phil Ross, a University of Waikato marine ecologist, told the hearing's commissioners, that he was "not overly concerned" about the remaining wreck debris having severe ecological impact if consent was granted.
"From what I have seen so much of the mobile debris has been removed and is continuing to be removed," he said.
Steve White, a consulting marine coastal consultant, said the reef was not in a pristine state prior to the grounding, and there had been considerable salvage efforts to reduce the potential ecological impacts.
"It's important to recognise that, while there may be effects due to the wreckage and debris at the wreck site, these effects are quite localised in extent ... The wreck has been, and continues to be, colonised and populated by ecological complex communities of organisms."
Independent fisheries expert witness Richard Boyd said, in his opinion, there was nothing that suggested the Rena grounding, its immediate after-effects or the presence of the wreck had in any way resulted in loss of any seafood species.
Mr Boyd said ecological surveys and diver observations indicated there had been an increase in fish at the reef over the past four years.
Rob Greenaway, a consultant recreation and tourism researcher and planner, said he had consulted a number of groups in the industry, including 73 tourism charter operators
"I have reached a strong and consistent conclusion that retaining the wreck remnants on the reef, and limiting as far as possible the period of restricted access to the reef for the public, and for commercial tourism operators is the preferred approach for recreation and tourism," he said.
* Prior to Rena's grounding at least 21 charter operators used Astrolabe Reef
* 10 commercial operators spent 50 per cent or more of their time in or around the reef.
Source: Independent recreation and tourism consultant Robert Greenaway