Fuller said the cancellation was due to "personal attacks" received through school email addresses and the school Facebook page, which were "extremely upsetting" for the people involved.
The abuse, which Fuller said was not appropriate to describe, was so bad the school had to temporarily remove its Facebook page.
"We had a month to go before the event and felt the negative social media comments could harm our little school more than the benefits of the fundraiser. A huge number of our community members are extremely upset about this event being cancelled.
"The people commenting on the petition were mainly from overseas and did not seem to realise that in New Zealand possums are a serious pest animal and are a threat to our forests and native wildlife and that we are allowed to shoot them to help control their ever-increasing numbers."
The petition, which gained more than 13,000 signatures, was started by organisation Lady Freethinker, a nonprofit group based in Los Angeles that researches animal cruelty around the world and campaigns against it.
Children have been taught to hate these possums simply on the basis they've been labelled as pests.
"I started the petition because it's inherently wrong for a school to teach young children that killing sentient beings, who suffer and feel pain just like we do, is a fun and rewarding activity. This is a dangerous lesson that can lead to a lifetime of callousness and cruelty. Killing is just not something kids should be taught to celebrate," said founder Nina Jackel.
She said the organisation did not direct any abuse at the school.
"We encourage compassion, not abuse."
Kiwi activist Lynley Tulloch said she was planning on getting in touch with other schools to talk about "the negative side effects of possum hunts and how they might affect children developing relationships with animals".
She said many people were unaware schools carried out possum hunts.
"There seems to be quite a divide, I think, between rural New Zealand and people internationally."
It's an opportunity to teach kids where their food comes from and how it's produced.
Tulloch believed "killing animals in conjunction with children's education" was wrong, and children should be taught about "compassionate" conservation.
"Children have been taught to hate these possums simply on the basis they've been labelled as pests."
Hunter Jamie McFarland disagreed that such events had a negative effect on kids.
He said hunting provided an educational opportunity for children to learn how to handle a firearm and how to "process" an animal.
"It's a cycle of life. It's an opportunity to teach kids where their food comes from and how it's produced. Not everybody gets an opportunity to see that process up front."
After a photo of him and his son with a goat they had killed was posted online, Facebook users labelled McFarland a child abuser and his son a future serial killer.
"None of these people have ever met my son."
He said learning to hunt was an important part of his childhood and gave him skills he has carried through to his adult life, and he hoped his son would pass those skills on to future generations.
He previously lived in a dairy farming area, and said if possums spread TB through the cattle it would be "devastating" to the community.
He said the school in his area would make about $7000 from possum hunt events, a figure which made a big difference in a community where the average income was about $35,000.
He said the possum fur industry was also big in the area and was another way of providing income.
