Dead dolphins test negative for algal toxins

Tests on eight dolphins which died in Auckland over a three week period have come back negative for algal toxins.

The tests were being conducted as part of the investigation into the deaths of dogs from a toxin found in sea slugs.

The Conservation Department says earlier tests have also ruled out brodifacoum, the rat poison it has recently used on Rangitoto and Motutapu Islands.

DOC says it has now exhausted all lines of inquiry and we may never find out why the dolphins died.

- NEWSTALK ZB