Agencies’ tug-of-war over dead koura

Investigators into a possible contamination of a South Waikato stream were left guessing after a bureaucratic tug-of-war over three tiny aquatic critters.

Waikato Regional Council’s search for answers into the deaths of hundreds of freshwater koura at the Oraka Stream, Putaruru, was ruined by a slack ministry response to a potential biosecurity disaster, investigations and incident response manager Patrick Lynch told the Environmental and Services Performance Committee last Wednesday.

A trout fisherman discovered the dead and dying koura on December 20, 2016. Council contacted the Ministry for Primary Industries (MPI) on the same day but Lynch said they failed to attend.

‘‘By early to mid-january, we got contacted by the MPI,’’ Lynch said.

An overseas scientist, made aware by media interest, pointed out to the ministry the deaths could be a result of crayfish plague - a disease not found in New Zealand that would have triggered a quarantine and forced the alert of trade partners, Lynch said.

‘‘There was a tug-of-war over a couple of days between me and MPI because we only had these three koura,’’ Lynch said.

Lynch said although the number of koura collected by regional council staff was small, it satisfied its level of investigation.

But the increased risk of crayfish plague forced council to hand over it’s three samples to MPI.

The MPI dissection of tiny animals, at an animal health laboratory in Wellington, found no trace of crayfish plague and left very little else to be tested - less than one gram of koura remained. The minimum sample for council’s analysis was 20 grams.

But further examination of the stream gave it the all clear.

‘‘We’re surmising that there has been a single strike incident in a tributary upstream and a colony of koura that have been impacted.’’

The Ministry did not respond to emails but in a February statement said it relies on local authorities and communities to support its investigations.