Scientists urge caution before quake debris is pushed into sea
Scientists have warned that pushing quake debris into the sea could affect paua and crayfish populations on the Kaikoura coast, disrupting the area's food web that includes its main drawcards: whales and dolphins.
State Highway 1 around the Kaikoura coastline was badly hit by landslips caused by the monster 7.8 magnitude quake that hit the South Island on November 14.
University of Canterbury experts told Radio New Zealand that local reefs were already compromised and were worried about how dumping more gravel could magnify the damage.
"The real question is, how limited is that in-shore rocky reef along that area and are we willing as a nation to sacrifice those reefs for a number of years in order to clear those roads?," marine science professor David Schiel said.
His colleague, Sharyn Goldstein, added reduced productivity among paua and crayfish caused by blocked light in the area could have an effect on larger sea mammals.
"A lot of the young fish that the seabirds feed on come up that phytoplankton and that zooplankton created within the surface waters relying on that productivity and clarity in the water so it's certainly feeds all the way up to the larger iconic species," she told Radio New Zealand.
Earlier this week, one government scientist said early signs are encouraging for stranded paua moved back into the sea after the earthquake lifted the seabed out of the water.
Thousands of paua left above the waterline were relocated to the sea in the wake of November 14's 7.8-magnitude quake in an effort to save them.
A government scientist says an inspection of the paua beds along the coast was heartening and they appeared to be doing well.
"It will be a while before we know for sure if they have taken to their new environment," fisheries scientist Julie Hills said.
She said paua had the ability to evolve to fit a changed environment but warned that adaptation will take time.
"It can sometimes take many, many years. This area of Kaikoura's coast will need careful treatment and management for some time to come," Dr Hills said.
The earthquake raised the region's seabed by up to 4m in places in an area nearly 100km long, leaving a large number of paua stranded and dying above the ocean waterline.
The government has closed the shellfish fishery along the coast for three months.
Volunteers, local iwi and Ministry of Primary Industries had combined to save as much of the molluscs as possible and work was still continuing.
"This has been a true collaboration between iwi, volunteers, industry and government and I'm so proud to have been part of it," said Mike Vincent, founder of the paua rescue group.
The government has also put together a $2 million science package to better understand the quake's ongoing impact to Kaikoura's marine life.
- With NZ Newswire
