A Kāwhia local reported that 134 dead birds had washed ashore on the coastline, and most of them were juveniles.

A Kāwhia local reported that 134 dead birds had washed ashore on the coastline, and most of them were juveniles.
More than 100 dead birds were found along the King Country coastline, near a biodiversity hotspot.

A Kāwhia local reported 134 dead birds had washed ashore between Kāwhai Ocean Beach and Aotea Harbour on Saturday.

Ōtorohanga District Council and the Department of Conservation were notified, and it's believed high tides sweeping over a breeding colony on nearby Gannet Island were to blame.

The dead birds were initially mistaken as albatrosses, then identified as gannets by DOC - with 117 of them juvenile gannets, known as gugas.

Seeing dead gannets along the Kāwhia coastline isn't unusual, though it may be a troubling sight for locals, Waikato senior ranger bio-diversity Nigel Binks said.

"Just off the west coast we've got an island called Gannet Island, and it's the most substantial gannet breeding colony in the country," Binks said.

With its 1.8 m wing-span, the Australasian gannet is a conspicuous, predominantly white seabird that is common in New Zealand coastal waters (File Photo).

With its 1.8 m wing-span, the Australasian gannet is a conspicuous, predominantly white seabird that is common in New Zealand coastal waters (File Photo).
"Last week, unfortunately, we had 10-metre swells.


"What we suspect is that the swells flushed the breeding colony and knocked young birds out of those nests, and that's why so many of those young birds have washed up to shore a couple of days later."

Binks said these events are known as storm casts.

Storm casts occur all around the world and can result in thousands of dead birds, particularly coastal birds like gannets, washing up ashore.

DOC members will be walking the coastline in the coming days to monitor if more wash ashore.

"The severe weather, especially with the tides that we saw at the end of last week, has definitely calmed down now.

"There's a chance more birds might wash up, but they've moved from a coastal island so a number of those birds may or may not have been predated upon [along] the way by sharks. So we can't be sure 134 was actually the total number of birds affected by the storm."

Gannet or Karewa Island is a biodiversity hotspot around 12 miles off the coast of Kāwhia.

It's not known how many different species are on the island, other than it being Waikato Region's only breeding site for the New Zealand fur seal, as well as one of New Zealand's largest breeding colony of Australasian Gannets or Tākapu.

"No one can actually get onto the island, there are very rocky cliffs on the outside of it, so our data is outdated.

"As part of our ongoing investigation DOC will be making an assessment of the breeding colony."

DOC is conducting biopsies and specimens of the dead birds. The organisation is discussing how to best dispose of the carcases with local iwi.

Source: Waikato Times