Abundance of life on the Owahanga River

Tracey Sorensen grew up on her family’s sheep and beef farm, Cathill, beside the Owahanga River, but she had never fully appreciated the abundance of aquatic life co-existing right beside them until a fish monitoring project run by Horizons Regional Council (HRC).

With support from the Puketoi to the Pacific Catchment Collective, the HRC fish passage team carried out a spotlighting survey on a 150-metre reach of the river at their farm on the Coast Road, Pongaroa, back in March.

The results were a revelation to Tracey, who had always had a perception of the river being muddy and dirty, due to sediment and fluctuating river levels.

The monitoring revealed there were a range of native/endemic species present, including Inanga (whitebait), Common Bully, Eel, Smelt and Koura (freshwater crayfish). The report said Inanga were considered to be the weakest swimmers of our whitebait species, not able to swim past many instream barriers, like dams, culverts and weirs. Their presence indicated a lack of barriers to fish passage downstream of the site.

“Freshwater mussels, crayfish and shrimp are species which ecologists regard as indicator species. The presence of these species at this site indicates a healthy ecosystem and good water quality,” it said.

Tracey says she has a greater respect for the river as a result, and was gobsmacked to learn of the variety of species present. The whole experience was a positive one, which has only served as a further motivator to continue caring for the land they farm.

“I have lived here my whole life and I never realised there was such an abundance of life there (in the river). Anyone who cares for the land likes to know that it’s healthy. It felt amazing to see these results.”