Archaeological investigations of 12 potential burial-like anomalies discovered last month on Wadjemup / Rottnest at the site where the remains of one Indigenous person were uncovered have found no evidence the anomalies contained further human remains.
Whadjuk Aboriginal Corporation and the Rottnest Island Authority announced the findings on Thursday in a joint statement.
WAC and the RIA said the process was overseen by four Aboriginal monitors and Elders.
A Ground Penetrating Radar (GPR) survey and archaeological investigation followed the discovery of human remains on April 8 during recent works to expand Wadjemup's main bus stop, which were identified as being male and consistent with Aboriginal ancestry after forensic examination.
The survey identified 12 additional potential burial sites on Wadjemup / Rottnest Island. Further examinations have found the anomalies did not contain human remains.
From 1838 to 1931, colonial authorities used Wadjemup as a prison for Aboriginal men and boys. Nearly 4,000 were held in appalling conditions and hundreds were buried there.
Known culturally as Baalang, the remains found on April 8 were returned to their resting place following a cultural ceremony.
Whadjuk Aboriginal Corporation and the Rottnest Island Authority have worked together since the discovery of Baalang to ensure cultural protocols are followed, and said on Thursday "respectful decisions are made regarding the protection and ongoing management of Baalang's site and the adjacent expansion of the Island's main bus stop".
"RIA and WAC recognise the profound cultural and spiritual significance of Wadjemup to Whadjuk Noongar people and the broader Aboriginal community. We acknowledge and express our deep regret for the significant distress the recent discovery and subsequent investigations have caused Aboriginal people," the two organisations said in their joint statement.
"WAC encourages Aboriginal community members to reach out to their office or their local Aboriginal Corporation for support and information."