Unseen invaders: How the global flower trade is spreading frogs, snakes, and insect pests

According to an article from BBC.com, frogs, lizards, snakes, spiders, and other insect pests are being transported worldwide through cut flowers and potted plants, posing a potential threat to nature, scientists warn.

These "clandestine intruders" have already included a frog that appeared among roses at a florist in Sheffield and snakes found in ornamental olive trees shipped to various countries across continental Europe.

Researchers from the University of Cambridge warn that these shipments may also contain invasive pests capable of causing serious damage to crops and rural areas.

With the rapid expansion of the global market for plants, bulbs, and cut flowers, scientists emphasize the urgent need for stricter regulations.

"Adult snakes and lizards are just the tip of the iceberg," said Professor William Sutherland from the University of Cambridge. "If they are slipping through controls, what are the chances of detecting small insects and fungi—the real troublemakers?"

The ornamental plant industry is growing rapidly and expanding into new regions, particularly in East Africa and South America.

Although there are regulations and border inspections, the high volume and speed at which cut flowers and ornamental plants are traded make it extremely difficult to intercept all the pests and diseases they may carry, explained Dr. Silviu Petrovan from the University of Cambridge.

"Even with the best intentions, unwanted stowaways are slipping through customs controls all the time," he said.

A reptile expert, Petrovan was once called to identify a live frog found at a florist in Sheffield.

At first, he thought it was a joke but was surprised to discover that it was actually a tree frog that had arrived with roses from Colombia, via Ecuador.

In the UK, frogs, lizards, and insects are among the most frequently detected stowaways.

On continental Europe, various exotic species of reptiles and amphibians have been accidentally found, especially in potted ornamental olive trees, including:

- Lizards, such as geckos, and several species of European snakes

- Frogs and toads

- A large number of insects considered agricultural pests

In a study published in the journal Bioscience, the research team analyzed records of pests found in ornamental plants during customs inspections in the Netherlands (2017–2018), as well as reports made to the UK Department for Environment, Food, and Rural Affairs (2021–2023).

The researchers are calling for stricter production standards and the collection and sharing of data on specific risks associated with the ornamental plant trade.