The B.C. government's resident bee expert says three Asian giant hornets found in Nanaimo this summer likely aren’t the only ones on Vancouver Island.

The dangerous invasive species was discovered on the island in August but only revealed by the Ministry of Agriculture on Wednesday.

The revelation has local beekeepers worried as the world's largest hornets are known to feed on honeybees and can destroy entire colonies in a short time.

"The Asian giant hornets are the apex hunters of the insect world," provincial apiarist Paul Van Westendorp told CTV News.

"The fact that there are three proves there must be a nest."

The Asian hornets are thought to have likely travelled to the island in a shipping container. The four-centimetre-long hornets may pose a public health risk, said Van Westendorp.

"The amount of venom a person will get may well threaten their health, may well threaten their well-being," he said.

In 2013, 41 people in China were killed and 1,600 were injured when the predatory pests plagued the province of Shaanxi.

The hornets are native to East Asia, and the climate on Vancouver Island probably feels like home, Van Westendorp said.

"It can probably adapt to our environment very readily without any problems."

The apiarist said that hornets are currently entering their dormancy period, meaning they likely won't pose any threat until spring.

However, anyone who thinks they've spotted one of the invasive thumb-sized hornets is asked to report it immediately.

"Take a good photograph, in focus please, and just email it to us," Van Westendorp said. "Ninety-nine per cent of photographs can be identified right away."

Officials ask that people contact the Invasive Species Council of B.C. at 1-888-933-3722 or file a report through the government's "Report Invasives" mobile phone app found here.