Inlet Best Health in Years
12 Jul 2014
Pauatahanui Inlet might become a foodbasket once more, with a new survey indicating the health of the harbour is at its best level in 22 years.
Cockle numbers in the Porirua waterway have grown from 227 million to 336m since 2010, a 21 per cent increase, and a rise of 87 per cent since 1995.
The figures come from a three-yearly survey run since 1992 by volunteer group Guardians of Pauatahanui Inlet.
The eighth survey was done in December 2013. Its results, analysed by the National Institute of Water and Atmospheric Research, were encouraging, said Guardians member John Wells, a former zoology professor.
Shellfish were good indicators of pollution because they filtered so much water, but cockles in particular had very short breathing tubes, so sank and drowned when fine sediment carpeted the harbour floor, Wells said.
Shellfish were good indicators of pollution because they filtered so much water, but cockles in particular had very short breathing tubes, so sank and drowned when fine sediment carpeted the harbour floor, Wells said.
