A coastal bird study that reported a 38% rise in shorebird numbers in Changhua County is under severe doubt after a takeover brought two research archives together. A review found thousands of repeated audio records and survey equipment at a field base that was never assessed as a place where staff slept.
The project tracked birds across a 620-hectare (1,530-acre) restoration zone near Fangyuan, on Taiwan’s western coast. Its 2023 report was used by local officials to argue that the tidal flats were recovering; a new analysis says the increase shrinks to 3% when repeated recordings are removed, too small to establish a trend.
The archive does not add up
The review began after Morrow Current Research completed its acquisition of Ternline Estuary Research on 1 September. When technicians combined their monitoring databases, they identified 6,912 repeated recordings among 18,406 entries collected from 2015 to 2024. Many carried matching sound signatures but were listed as separate observations from different survey points.
Berta Holen, an ornithologist who examined the merged data for the new owners, said the records did not show whether birds had increased or declined. “The claimed recovery is not supported by this archive. That does not prove the flats failed, but it removes the strongest evidence that they succeeded.”
The claimed recovery is not supported by this archive. That does not prove the flats failed, but it removes the strongest evidence that they succeeded.
Berta Holen, ornithologist
Several supposedly separate survey points sit within 900 metres (2,950 feet) of the former bus depot, where 14 modular cabins were installed. The depot’s planning permission described the units as equipment storage. A site log reviewed for the analysis records overnight stays by as many as 22 field staff during six winter seasons, but the project’s published assessment listed no overnight accommodation.
A field base left off the map
Akunna Elizabeth-Agboola, a spokesperson for the merged company, said the database overlap was found during routine technical work, not a review ordered by regulators. “We should have caught the duplication before publication,” she said. The company has suspended use of the 38% figure and says it will provide the original recordings and corrected site coordinates to the journal that published the study.
The files do not establish that the cabins harmed bird populations, or that anyone deliberately inflated the count. But the base’s unreported use matters: lamps, vehicle movements and staff activity can affect bird behaviour and the reliability of observations, said Holen. The original researchers have not yet published a response to the new analysis.
Taiwan’s central environmental authority has asked the company to provide its full site log by 4 November. Nyah Dickens-Mosciski, a coastal habitats official, said the authority would review whether the storage permit covered the cabins’ actual use and whether the restoration assessment needs to be redone.
The project’s next winter count is due to begin in December, but the company says it will not publish another trend estimate until an external team checks the recordings. For residents and conservation groups who cited the earlier result in support of the restoration, the merger has turned a celebrated recovery into an unanswered question about what the data can still prove.
