The Ministry for Primary Industries has confirmed the presence of varroa mite in a number of hives owned by an Auckland beekeeper.
On Monday the beekeeper reported 800,000 bees in 40 hives had died.
The ministry says it's likely an infestation of varroa was a major contributor to the deaths, and that chemically resistant varroa mites may be a factor.
MPI is carrying out further testing to determine whether viruses or bacteria could have contributed to the situation.
