The HS2 high-speed rail project will destroy and divide "huge swathes" of "irreplaceable" natural habitats, The Wildlife Trusts has warned.
According to the organisation, 108 woodlands are at risk and 21 nature reserves could also be affected.
The group said its new report, which incorporates data from 14 Wildlife Trusts impacted by HS2, is the most "most comprehensive" assessment of the environmental damage the high-speed rail project could cause.
The Wildlife Trusts' report outlines the following at risk of loss or significant impact if the current proposals are carried out:
Five wildlife refuges or international importance
33 sites of Special Scientific Interest
693 Classified Local Wildlife Sites
21 Designated Local Nature Reserves
26 Large landscape-scale initiatives, including four nature improvement areas awarded £1.7 million of public money
18 Wildlife Trust Nature Reserves
108 "irreplaceable" ancient woodlands
In addition, the trust warned "rarities" like the dingy skipper butterfly could also be made extinct locally, while barn owls and endangered wildlife such as white-clawed crayfish could be impacted.
A spokesperson for HS2 Ltd said: "The number of sites presented in this report as being 'at risk of loss, or significant impact' simply isn’t accurate".
The trust has called for a "new" and "greener" approach if the HS2 project is to go ahead.
Nikki Williams, The Wildlife Trusts’ director of campaigns and policy, said: "The figures are grim and the reality is worse.
"HS2 will destroy precious carbon-capturing habitats if it’s allowed to continue in its current form. It will damage the very ecosystems that provide a natural solution to the climate emergency."
She said HS2 Ltd’s proposed mitigation for the environmental impact was "inadequate".
It has now called on the Government to “stop and rethink” the project.
In a tweet, the National Trust said it welcomed the report and added "HS2 Ltd has a vital responsibility to lead by example and get this right by delivering a net gain for nature".
HS2 Ltd said it will deliver a railway that "respects" the natural environment through the creation of a "green corridor" along the route.
According to the company’s website, nine square kilometres (3.4 square miles) of new woodlands – made up of seven million trees and shrubs – will be created.
The company claims that figure is more than double the amount affected by the project.
HS2 Ltd also promised a further four square kilometres (1.5 square miles) of wildlife habitat will be established along the route.
A spokesperson for the company added: "HS2 take the environmental cost of construction very seriously."
The group also says the rail line will help cut the number of cars and lorries on the roads and demand for domestic flights, which will help the country’s fight against climate change.