NZ Transport Agency Waka Kotahi (NZTA) began work last month to retrain the Kyeburn River across a wider path under the bridge to protect the abutments from erosion.
In 2019, seven moa footprints were discovered in the riverbed close to the bridge by Ranfurly man Michael Johnston.
They were the first moa prints found in the South Island, although bones and fossilised droppings had been found. The footprints were removed shortly after their discovery by staff from Tūhura Otago Museum and University of Otago and taken to the museum.
Museum natural science curator Kane Fleury said the erosion that was damaging the bridge foundations was the kind of event that would have eroded the moa footprints from the river bank.
"I would just hope that the contractors are keeping an eye out for any other footprints or trackways that might be discovered in the area."
Mr Fleury said while there were no active searches in the Kyeburn at present, he would be very interested in studying and documenting anything found as a result of the earthworks.
He said there was a high chance of material showing up after flooding or earthworks anywhere in the Maniototo. It was a huge area, so the museum relied on people alerting it to finds.
Mr Fleury said if people did find fossils, they should photograph them immediately and not try to remove them.
"Once they are exposed to the surface they are at their most fragile. The chance of them being damaged is incredibly high and it can happen quickly.
"It is at this point that taking photos and asking experts if they are interested is the most important.
"People should always be keeping an eye out for archaeological and palaeo finds and taking photos and calling their local museum if they find something they think might be interesting. The context of the find is important and removing these things can be complex so seeking advice is always important."
Mr Fleury was part of a team of research scientists from the University of Otago geology department, Tūhura Otago Museum, Victoria University of Wellington, the Australian Nuclear Science and Technology Organisation and Aukaha Consultancy that released updated information about the markings in November last year. The group established the footprints were 3.6 million years old and from the Emeidae family, a relative of the heavy-footed moa — which were bottom-heavy with unusually short and thick legs.
A 3D photogrammetry model of the fossil site revealed there was also possibly a member of the Dinornis genus, which included the largest-known species of moa — the South Island giant.
Fully grown females are thought to have been up to 250kg. Although the Kyeburn precursor was lighter, it was still impressive at an estimated weight of 158kg.
