Sleeper pests like the red-eared slider turtle (pictured) could begin to threaten the local ecosystem due to a warming climate. Photo / File
Sleeper pests like the red-eared slider turtle (pictured) could begin to threaten the local ecosystem due to a warming climate. Photo / File
"Sleeper pests" such as turtles and water dragons could spell major trouble for Bay of Plenty ecosystems as the climate warms.
According to Toi Moana Bay of Plenty Regional Council, sleeper pests are already in the environment, but because of current climate conditions, they are unlikely to breed successfully.
With climate change bringing warmer average temperatures we may begin to see more pest plants producing viable seed and pest animals successfully raising young, the council said.
Red-eared slider turtles are one of many sleeper pests that the council fears high summer temperatures may turn into a major threat to native ecosystems.
Regional Council biosecurity officer Garrick McCarthy said the team was already starting to see abandoned and escaped pets reproducing and thriving in environments they previously had been unable to live in.
"We have found viable red-eared slider turtle eggs in Tauranga's Carmichael Reserve, and a Plecostomus, an ornamental catfish from the Amazon, living in a stormwater drain in Pāpāmoa," he said.
"We also have video evidence of an eastern water dragon swimming above the McLaren Falls," he said.
"With the changing Bay of Plenty climate these species could have a far greater impact on the environment than ever before. The lack of natural disease or predators means these exotic pets can live longer and raise young in the wild.
"They're here already and so the risk of them becoming an established pest is very real."
The Invasive Species Specialist Group has listed the red-eared slider turtle as one of the world's 100 worst invasive species.
The turtles are readily available in pet shops throughout New Zealand. However, as they can live to be 50 years old, they are often dumped in the wild when their owners become bored of them.
Worryingly, community groups have also reported catching red-eared slider turtles in the Rotorua Te Arawa lakes.
Viable red-eared slider turtle eggs were found in Tauranga's Carmichael Reserve. Photo / File
Red-eared slider turtles are aggressive, often chasing down prey far larger than themselves. They feed on a wide variety of aquatic plants, insects, eels and small fish species like whitebait.
They nest in holes in the ground, which are covered while the eggs mature. The ground temperature must be sufficiently warm for the eggs to hatch and temperature also determines the sex of the turtle. Lower temperatures will produce males and higher temperatures produce females.
The fear is with rising temperatures, eggs will hatch and females will be produced. An adult female can lay up to 150 eggs in one year.
The council said they were always surveying for potential plant and animal sleeper pests, so that pre-emptive action could be taken before they caused significant harm to the environment.
However, McCarthy said prevention was the best form of biosecurity.
"People should seriously consider whether such a long-lived animal like a red-eared slider turtle is right for them as a pet.
"If it does come to a point where you no longer want your pet reptile or fish, we ask that you do the right thing and rehome them, not release them into the wild," he said.
There are many turtle, fish and reptile enthusiast groups on Facebook and these may be a good place to start when looking for a new home for your exotic pet.
McCarthy also asked that people reported any sightings of the turtles or their nests to the regional council biosecurity team.
"There is also the potential for other species of exotic bird, reptiles or fish to be a sleeper pest, so if anyone sees something unique or out of place, especially if its spreading or raising young when before it didn't, then please get in touch with us," he said.
