Mystery continues to surround reports yesterday (12 Feb) of large numbers of dead and dying Canada geese and Shelducks on Te Anau's shoreline near the Upukeroa River, but nonetheless sparked an immediate response from Southland agencies.

In 2024 the Te Anau lakeshore was the scene of the mysterious deaths of 64 paradise shelducks, prompting speculation from Otago Fish & Game Chief Executive Ian Hadland that the agricultural insecticide diazinon may have been to blame.

Following multiple calls to Environment Southland (ES), the agency issued a warning yesterday that people and pets should avoid the area, as they sought more information, while also alerting the Department of Conservation (DOC) and the Ministry of Primary Industries (MPI).

A Southland Fish and Game staff member was also immediately sent to the scene but subsequently failed to find any evidence of the reported mass mortality.

DOC operations manager Te Anau John Lucas said they had also received reports of a number of dead birds near Te Anau, however initial investigations had not located any signs of mass mortality.

If people come across a large number of dead birds in the wild please contact MPI, he said.

MPI said because no dead birds had been located, they have no concerns for exotic disease and would not be investigating further unless new information came to light.

ES has today (13 Feb) rescinded its warning.

Canada geese have been an ongoing problem throughout Fiordland, with large flocks not only polluting waterways and beaches but also fouling and mowing down agricultural pasture.

Fiordland Community Board chair Diane Holmes agreed the geese were a problem and said the board had raised their concerns with DOC on several occasions.

Lucas said DOC viewed the geese as an agricultural pest but admitted they can also become a nuisance when large numbers occur where people recreate - "especially at this time of year due to fouling i.e. Te Anau's lake-shore."

"Canada geese have a minimal impact on biodiversity values, however the Department has undertaken Canada Goose control alongside PAMU and Fish and Game for the last 3-4 years at specific sites where they are considered a nuisance," he said.