Guardian Australia has detected and addressed a significant vote-tampering event in the Australian bird of the year poll.

On Sunday 10 November, a spike in the vote count for the cockatoo was observed by readers and flagged with us. We do check for strange voting patterns regularly, and have detailed logs to identify automated voting. We’re not going to go into too much detail on what we’re recording, as we’d like to make it slightly more difficult for poll-riggers.

After running our analysis, it is clear that automated voting was conducted for three birds – the rainbow lorikeet, the cockatoo, and then the black-throated finch, with unusual spikes in the number of votes received per minute from the same origin:

Australian bird of the year poll suspicious voting.

This is not the first bird-poll-fixing controversy. In 2017, someone tried to spam the the first Australian bird of the year vote with votes for the powerful owl. In 2018 fraudsters targeted the New Zealand poll with votes for the shag.

While we do perform some checks on the validity of votes before automatically displaying the count on our site, there is always a trade-off between making it easy for regular people to vote, and ensuring the process is relatively secure.

For example, we could add an email verification step for each vote (as the New Zealand bird of the year poll does), but we’d like to keep the process as simple as possible and do most of our validity checking once the votes have been received. And, at the end of the day, this isn’t a political election – it’s a bit of fun.

In the current case we’ve removed around 4,000 votes, and will continue to check for suspicious activity as the poll continues. You can vote for your favourite in the top 10 runoff vote until 5pm AEST Thursday.