Leslie Gilder told chrislynchmedia.com she was shocked to discover the plaques, including one bought by the citizens of Christchurch in December 1963 for Ashgrove Reserve in Somerfield, had gone missing.
Gilder told chrislynchmedia.com an Addington Cemetery plaque commemorating the lives lost to deadly diseases like typhoid in the 1880s was also missing.
Gilder reported a drinking fountain at Dickens Street Reserve in Addington had disappeared and another plaque in Ruskin Reserve had gone missing, she told chrislynchmedia.com.
Gilder said the plaques were likely stolen but she believes scrap metal dealers in the city would recognise them.
Gilder is part of a global treasure-hunting group called "Geocachers" where people use GPS or smartphones to find hidden containers.
Gilder told chrislynchmedia.com the plaques hold key information vital to the game.
"I’m also a huge fan of plaques, and I absolutely love history,” Gilder told chrislynchmedia.com.
"Losing these plaques robs us of pieces of our shared heritage and makes it harder for others to connect with the past.”
Said Christchurch City Council head of parks Rupert Bool: "The ... council shares the community’s concerns about the disappearance of historic plaques, which commemorate significant events and individuals that have shaped our city.
"We take these incidents seriously, recording all reported thefts and allocating an annual budget for plaque renewal or replacement to preserve our shared heritage," Bool told chrislynchmedia.com.
"To address the rise in thefts targeting plaques for scrap value, the council is exploring alternative materials that deter theft while maintaining historical integrity."
