The prime minister has been accused of inventing an allegation that wildlife rules are holding back house-building.
In his recent speech on job creation, Boris Johnson said: “Newt-counting delays are a massive drag on the prosperity of this country.”
But environmental groups say the allegation is a political trick with no basis in fact.
And BBC News has been unable to find recent evidence that wildlife surveys are unduly delaying development.
The Local Government Association said it was not aware of any evidence that newt surveys were unnecessarily holding back projects.
And a property industry source said it had many concerns over planning, but newt surveys were towards the bottom of the list.
“The PM’s speech was pure fiction,” Craig Bennett, head of the Wildlife Trusts, which runs conservation projects and education projects, told the BBC.
“It may sound funny referring to newts, but actually it was rather sinister. In the environment movement we know referring to newts is a dog whistle to people on the right of his party who want environmental protections watered down.”
Number 10 says Mr Johnson’s remarks were based on government enquiries into red tape.
Historically, would-be developers would have to wait for a survey to check whether their plans might disturb great crested newts, which are uncommon in Europe.
A 2017 review said newt survey delays could typically last nearly 15 weeks, which could make it hard to secure investment. One house builder reported the cost in 2013 at an average of £2,261.55 per newt relocated.
This took into account consultant fees, land purchase for the relocated newts and contracting costs for the physical relocation. Another large builder reported a sum of £500,000 spent on one site where just five newts were found.
But the wildlife watchdog Natural England says recently it’s been working hard to restrict delays and costs.
It’s using a method in which samples of pond water are taken and analysed to detect fragments of newt DNA.
The process is so fast that the organisation is often able to carry out research in advance so developers can get instant information.
Source: Froglife
A springer spaniel called Freya is also playing a part. She works for Wessex Water, sniffing out newts in ponds. The firm says that, thanks to Freya, it can conclude its surveys in days, not weeks.
What’s more, if great crested newts are discovered, that doesn’t sterilise development on the site.
Under recent rules, the developer can proceed so long as they provide alternative sites in a way that leaves nature better off than before. These changes may explain why newt surveys are no longer a great concern for many house builders.
Newt rules have been under attack in the past from politicians complaining that the UK has “gold-plated” EU regulations.
But the head of Natural England, Tony Juniper, told the BBC: “We have to find the best ways of pulling together our environmental ambition at the same time as the economic one. These two things have to be pursued together, not traded off against each other.”
Green groups furious with Mr Johnson are meeting Environment Secretary George Eustice next week to express their concerns about his speech.
Jeremy Biggs from the Freshwater Habitats Trust told BBC News the processing time for a newt search in the South Midlands was now down to 10 days.
But the former chair of Natural England, Andrew Sells, said there were still delays in some areas. He said: “The problem lies with local authorities. The new testing systems are there to be used, but they haven’t been rolled out in all places.”
Update: At the time of writing, no government department had offered evidence for the Prime Minister’s allegation that newts were causing serious delays. The story has since been amended following updated information from Number 10, which said his remarks were based on previous government enquiries into red tape.
Follow Roger on Twitter @rharrabin
Read MoreFeedzy
Narrow down the five most important aspects of your wedding that deserve the investment. Celebrate…
In a technology-driven age, managing IT infrastructure effectively is critical for businesses aiming to stay…
Chromatography may sound like a mouthful, but it plays an essential role in many fields…
Electric automotive actuators are tiny powerhouses working tirelessly behind the scenes to enhance your driving…
Explore how pressure transducers boost efficiency and reliability in water management systems by providing accurate…
Custom bags have become a popular choice for businesses and individuals looking to combine functionality…