A recent assessment of Australia's biodiversity offset program has disclosed that 30% of the evaluated restoration sites were now in worse shape than they were previously, casting doubts on the program's ability to save vulnerable species.

The federal environment agency commissioned the analysis, which revealed contradictions and shortcomings in implementing the promised habitat improvements.

The agency's report said about a quarter of the sites had "major inconsistencies" between what was pledged in the offest plan and the actual number of threatened species habitats or ecosystems at the location. Another 30% had "minor inconsistencies," the report revealed.

This has led to calls for immediate reforms, as concerns about the growing hazards to local animals have escalated.

Environment Minister Tanya Plibersek said, "I commissioned this audit because I was concerned about offsets. If people make a promise to protect nature, we expect them to keep it. If they don't, there should be consequences."

The Australian Conservation Foundation's Martine Lappan expressed her disapproval of the results, saying, "Australia's system of biodiversity offsets needs a complete overhaul as part of the reform of the national nature law. ... This report demonstrates that the conservation goals of offsets are a long way from the reality of what is happening on the ground. It shows offsets are not nature-positive and cannot be banked on," The Guardian reported.

Director of biodiversity council, James Trezise, said the offsets often "don't even protect the extent of threatened habitats that proponents claim they will. We can't offset our way out of the extinction crisis. ... Offsets need to be truly relegated to a measure of last resort."

One of the case studies that was featured was a place that was supposed to be a home for koalas and flying foxes, but it turned out to be mostly cleared ground with little ecological significance.

Pressure to reform national environmental legislation has increased on the Albanese government as a result of the findings. To overcome systemic failures in biodiversity and provide strong protection for Australia's endangered species and environments, Parliament is now debating legislation to establish the environment protection agency.

Plibersek said the proposed environment protection agency would be given the authority to conduct audits without previous notice.

"As we said in our nature-positive plan, we know the current offset arrangements are broken and making nature worse," she said.