Environmental laws that formally protect the endangered black-throated finch have also sanctioned the broadscale destruction of its natural habitat, leaving the species at risk of extinction, a new study says.

The study, led by University of Queensland research fellow April Reside, and published on Wednesday in the journal Environmental Science and Policy, charts the exile of the black-throated finch from more than 80% of its former range.

It reveals that 775 projects overlapping the finch’s habitat were referred to the federal government for assessment under the Environment Protection Biodiversity and Conservation Act since 2000. Only one was refused because of an unacceptable impact on the finch.

“All these projects proposed for the finch’s habitat were assessed independently, so the cumulative impact is not properly considered. It’s death by a thousand cuts,” Reside said.

“Often, extinctions happen because we just weren’t watching. This time, we have charted the steep decline of this Australian bird – but so far, we have permitted it to continue.”

The finch is listed as endangered under the provisions of the EPBC Act. But in almost 20 years since the act was introduced, the bird has retreated from its former range, which stretched from north Queensland to northern NSW. It remains on two primary sites.

One site is near Townsville. The second is in the Galilee Basin, where five proposed coalmines have approval to further clear and degrade areas of high-quality finch habitat.

Adani’s Carmichael coalmine still requires Queensland government approval for a conservation management plan to protect the finch – one of the significant roadblocks preventing the company from starting construction work.

Adani has claimed it is being treated unfairly in relation to the finch, that it has been subjected to reviews and required to satisfy conditions beyond those of other projects.

This week Adani’s Australian mining head, Lucas Dow, told the Courier-Mail that “mining projects create security of habitat that otherwise would not exist”. Adani plans to set aside 33,000 hectares of land as conservation offsets.

The study questions the effectiveness of offsets, which have commonly been required in the past when a development or project is predicted to have a detrimental impact on finch habitat. It says existing offsets have been found to be “of low habitat value”.

“In short, the offsets [proposed by Adani] appear unlikely to generate either the habitat improvement or the habitat protection benefits that were estimated, but even if they did, the net result of the approved losses and the offsets would be an enduring reduction in [black-throated finch] habitat.

“We urge that mechanisms to protect habitat for threatened species, as well as plans for offsets where habitat loss does go ahead, should be focused on ecological outcomes that support species recovery.”

The study says the “best-known remaining habitat” for the finch is at the Carmichael mine site, where Adani has approval to clear or degrade about 6,000ha of “critical habitat”.

“With so much of the habitat that once existed cleared or degraded, the remaining patches of habitat become increasingly important to the species’ persistence,” the study said.

At least three vertebrate species have gone extinct in the past decade.

“Australia and Queensland have laws to protect the environment, and together they are supposed to protect threatened species habitat,” says Reside.

“But they’re failing to do just that. With large-scale habitat destruction still being approved by governments, the finch may be next.”