The fate of a group of nesting shags at Timaru's port is attracting widespread attention on social media.

New Zealand media ​columnist Mike O'Donnell​ posted an image of the shags, nesting on a cantilever at the port, to social media on Sunday with the caption "is it true you are going to knock down these protected birds' homes tomorrow? What will happen to the chicks?"

In his post he said he understood PrimePort Timaru had scheduled the "shortening of this breakwater extension to make way for larger ships".

"No doubt good for the economic development of the region - but I don't understand why they can't wait a couple of weeks to let these protected birds raise the fledglings in their nine nests."

However, on Tuesday PrimePort chief executive Phil Melhopt said he was aware of O'Donnell's post and he was talking to the Department of Conservation about options as the cantilever would have to be temporarily moved in about two weeks time as part of a $2 million project to widen the port channel.

"It shouldn't affect any work we have to do," Melhopt said.

"The birds are protected so we have to go about it appropriately."

Melhopt said a dredge was coming from Auckland to widen the channel, allowing for vessels to navigate more safely and to meet best practice.

"It's a fairly sizeable piece of work."

O'Donnell in an updated post said; "No shags will be harmed in the making of the expanded port entrance - great response from Timaru District Council and PrimePort Timaru, everyone loves a Timaru shag".

The Department of Conservation could not provide comment before deadline.

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