The Department of Conservation says it will ''carefully manage'' the cereal bait laced with 1080 poison intended for the postponed Makarora ''battle for our birds'' operation.
Anti-1080 campaigners have suggested the bait was likely to deteriorate because of the delay until spring or early summer, and could be dumped.
Wanaka conservation services manager Chris Sydney said yesterday Doc ''carefully manages the purchase and use of 1080 bait'' to make sure it was effective and to minimise waste.
The palatability and toxicity of 1080 cereal pellets started to ''measurably decline'' about three months after manufacture, he said.
They also had an expiry date of one year after the manufactured date.
''Any bait that ages significantly beyond the expected use period is tested for toxicity to ensure it remains effective to control pests.''
Mr Sydney said last year, Doc ran 26 aerial 1080 operations as part of its South Island ''battle for our birds'' programme over more than 600,000ha.
The 1080 bait was bought and co-ordinated nationally to ensure sufficient bait for each operation.
''Bait not used in one operation was then redirected to another, provided it met the required specifications ... and was still fit for purpose.''
Bait that would have been used in the Makarora operation was available for use elsewhere, provided it met these conditions.