Posted by Nick Legard
While a picture (or 3 – see below) tells a thousand words, the mapping undertaken by the Ashley Rakahuri Rivercare Group (ARRG) shows the alarming trend of weed infestation in the Ashley Rakahuri. The grey areas are gravel, purple outlines are river channels. For all their ‘bare’ appearance, these gravel areas are biologically rich and crucial in the ecological and hydro-geomorphological processes of a braided river. Scroll down to see what’s happened to the gravel and the reduction in river braids in just six years.
For all their ‘bare’ appearance, these river gravel areas are biologically rich and crucial in the ecological and hydro-geomorphological processes of braided rivers and the estuaries that lie downstream.
Taggarts, who extract gravel from the river, have played a hugely positive role by working with ARRG to help clear weeds and keep channels open in stretches of the river where they operate, but there is only so much they can do. The question is, will this be allowed to continue? Will the river becomes so choked with weeds, it’s no longer a braided river? What will that mean for the birds? And what will it mean to the Ashley estuary, one of the largest, least modified estuaries in New Zealand?