Thomas finally retired to the Wellington Bird Rehabilitation Trust (WRBT) sanctuary in 2013 and he eventually went blind.
The WRBT confirmed with indy100 in 2018 that Thomas passed away on Saturday 3 February. It announced the sad passing on Facebook on Tuesday:
We have loved having Thomas as a part of the WBRT family and have treated him with extra special love and care!
He lived for corn on the cob and if it wasn't there when we put him back into his house at night, he was not happy.
Birdwatcher Mik Peryer, who was familiar with Thomas, told Stuff it was a 30 year love story “that should be celebrated". He added:
Prior to Henrietta turning up they had about 18 happy gay years together.
It is understood there is now talk of plans to bury his body next to his soulmate Henry in the park where they lived for all those years.
Meanwhile, tributes have been pouring in for Thomas from around the world.
My poor, brittle, polyamorous, bisexual heart is exploding.
"Thomas The Bisexual Goose Will Be Buried Beside His… https://t.co/pGI4QPds90