TAIPEI (Taiwan News) — A Eurasian otter living on the outlying island of Kinmen’s Tai Lake has been confirmed to be at least 11 years old, significantly exceeding the previously believed wild lifespan of less than five years, according to Taipei Zoo research assistant Jang-Liaw Nien-hung (張廖年鴻).

Speaking at a conference on Wednesday, Jang-Liaw described the finding as potentially groundbreaking, per CNA. The otter, a female first recorded by researchers in 2014, has been consistently observed since then, raising new questions about the longevity of Eurasian otters in the wild. He stressed that this older otter’s survival challenges long-standing assumptions.

Jang-Liaw analyzed data collected since 2013, noting that otters aged two years or younger consistently outnumber older individuals. Due to their solitary and territorial nature, he believes these young otters were likely born in Kinmen.

Jang-Liaw added that recent surveys show Kinmen is home to around 60 Eurasian otters, a population density significantly higher than similar species abroad. He also noted the otter population’s unique traits could limit the applicability of international otter research.

Despite the positive findings, Jang-Liaw warned on Tuesday, of troubling trends, per CNA. While otter populations in eastern Kinmen appear stable, populations in the western regions, including Lieyu Township, are in decline or have disappeared entirely.

Jang-Liaw said one contributing factor is overgrowing floating aquatic plants. He explained the plants could block river channels and degrade water quality, leading to habitat loss or drying waterways.

Jang-Liaw also highlighted the alarming trend of otter populations declining without identifiable cause in key habitats of western Kinmen. They are Ci Lake, Lake Shuangli, and the Huwei River estuary, all of which remain relatively intact.

Jang-Liaw warned that this ongoing decrease presents a serious concern for conservation efforts.